DASR SPA - Specific Purpose Approval

GM SPA.10 - Command Clearance (AUS)

Purpose.  (Context) On occasion, to maintain key capabilities at high levels of operational readiness and to undertake non-discretionary activities in support of Australia’s national interest, commanders may be required to operate aircraft outside of approved configuration, role, environment, limitations or conditions. (Hazard) Operating aircraft outside of approved configuration, role, environment, limitations or conditions may affect Aviation Safety. (Defence) This regulation requires the MAO to establish a process to manage risks to Aviation Safety for aircraft operated under a Command Clearance.

GM SPA.10.A – Command Clearance (AUS)

A Command Clearance is an authorisation that allows a Commander to operate an aircraft when such authorisation is not available under other DASR.

GM SPA.10.B – Command Clearance (AUS)

Due the breadth of circumstances that may be approved by a Command Clearance, the documentation of the decision-making process may range from a stand-alone Command Clearance approval that elaborates on the factors considered, through to being documented in the AMD risk assessment process as used for a Deferred Defect.

Where immediate operational or emergency needs preclude completion of a formal, documented process prior to the activity, the primary focus remains the management of risk, which should be eliminated, or otherwise minimised SFARP. A record of the risk management determination, and supporting recommendations and/or decisions should be collated as a formal record at the conclusion of the event.

Regardless of documentation method, the Command Clearance approval shall document the risk assessment.

In any Command Clearance decision and associated risk assessment process, the option not to conduct the activity remains valid.

GM SPA.20.A – Low Flying (AUS)

Purpose. The purpose of this regulation is to assure the safe management of low flying activities.

This regulation does not apply to non-Defence registered aircraft being operated by Defence aircrew; such operations are to be in accordance with the relevant civil air rules and regulations.

This regulation does not apply to non-Defence registered aircraft covered by Implementation Procedure for Australian Civil Registered Aircraft Operated as State Aircraft and Aircrew Licensing, see DASA Key Documents webpage for details.

GM SPA.30 – Purpose statement and context (AUS)

Purpose. (Context) Air Displays enable Defence to demonstrate the capabilities, values and professionalism of Defence Aviation. (Hazard) Ineffective management of Defence Aircraft operations during Air Displays can compromise Aviation Safety. (Defence) This regulation requires MAOs and UAS Operators to establish effective management controls for Air Displays to ensure Aviation Safety.

Applicability. DASR SPA.30(a) and DASR SPA.30(b) apply to MAOs and UAS Operators conducting Air Displays. Additionally, DASR SPA.30(c) applies to MAOs and UAS Operators conducting Display Flying. This regulation applies whether as part of a Defence, international or civil event, and regardless of event location. Further, unless stated otherwise, Air Displays includes rehearsals for an Air Display.

MAOs and UAS Operators may consider implementing some of the controls from DASR SPA.30(c) for Flypasts to eliminate, and if not reasonably practicable to eliminate, to minimise risks SFARP, even though that Part does not apply to MAOs and UAS Operators conducting Flypasts. For example, Flypasts may be flown by any Type-qualified Crew. However, MAOs and UAS Operators should consider whether additional selection criteria should be defined for Crew conducting Flypasts. Similarly, MAOs and UAS Operators may consider appointing an FDD for complex Flypasts (eg where disparate Aircraft are conducting a formation Flypast).

Specific terminology and definitions:

Air Display Committee (ADC). A group of suitably experienced persons appointed to assist the ADEO and FDD with the safety management of an Air Display. An ADC Chair may be appointed for complex Air Displays.

Air Display Event Organiser (ADEO). The person responsible for all matters pertaining to the wider planning and execution of an Air Display; and for the safety of the general public, both at the event and those affected by the wider impacts of the Air Display. The ADEO is a separate role to that of the FDD. However, the ADEO and FDD may be the same person.

Crowd Line. The line delineating the closest edge of any area, including car parks, accessible to Spectators with respect to the Display Area or Display Line.

Display Area. The Airspace in which Aircraft conducting Display Flying may manoeuvre.

Display Box. The ground area footprint in the Display Area, thoroughly investigated pre-flight to identify and locate all hazardous obstructions. The Display Box should be, SFARP, clear of Spectators and Secondary Spectators, and hazardous obstructions.

Display Crew. A generic term describing Flight Crew who are qualified and authorised to perform Display Flying.

Display Flying Supervisor (DFS). A suitably qualified and experienced person selected by the MAO or UAS Operator to supervise Display Crew during Display Flying training and rehearsals. The DFS is a separate role to that of the FLTAUTHO. However, the DFS and FLTAUTHO may be the same person.

Display Line. A line defining the track along which Aircraft conducting Display Flying should operate relative to.

Display Sequence. Defined as:

Alternative Display Sequence. A display sequence flown in circumstances when the weather (commonly referred to as a ‘low show’), personnel or Aircraft serviceability (in the case of Display Teams) precludes flying the intended Display Sequence.

Special Venue Display Sequence. A display sequence flown in circumstances where the venue is not suitable for flying a Standard Display Sequence. For example, an Air Display along a river can limit the Display Area laterally, requiring predominantly vertical manoeuvres along the Display Line.

Standard Display Sequence. All the individual manoeuvres, in chronological order, that are intended to be demonstrated during Display Flying.

Display Team. A formation of Aircraft conducting Display Flying as one single ‘act’.

Flying Display Director (FDD). The person responsible for ensuring Defence Aircraft are operating in a safe and appropriately planned Air Display environment (commonly referred to as the ‘Ringmaster’). An FDD should not be confused with the ADEO. However, the FDD and ADEO may in some cases be the same person.

Secondary Spectator. A person viewing an Air Display from a location which has not been specifically designated for Spectators. This definition includes other persons affected by the Air Display even though those persons may not be viewing the Air Display.

Spectator. A person attending an Air Display specifically to witness the event.

The Professional ADF Aviators' Reference Manual (PAARM) provides additional Air Display supporting material.

GM SPA.30(a) – Air Display Safety Risk Management (AUS)

Safety Risk Management (SRM). The safety of Crew, officials, Spectators and Secondary Spectators is paramount throughout any Air Display. The application of SRM, including Air Display - generic Mission Risk Profiles (MRP), will aid the Accountable Manager (AM) in identifying relevant Hazards and risk controls to eliminate, and if not reasonably practicable to eliminate, to minimise risks SFARP. Additionally, documented Risk Management Plans (RMPs) specific to each Air Display, will provide opportunities to implement necessary contextual controls. Air Display approvals are based on these SRM artefacts.

However, SRM should also be scaled to the size and complexity of the Air Display. For example, a Flypast by a single Aircraft over a graduation parade will not require the same SRM as a complex display with multiple participants.

In particular, MAOs and UAS Operators should consider the following Air Display - related Hazards:

Environmental Hazards. Air Display performance and risks to Spectators can be affected by environmental conditions. Close scrutiny of the expected weather at the Display Area and along the Flypast route will assist with identifying and controlling conditions that can directly affect the safety of the Air Display. Understanding the expected weather will also assist with determining which Display Sequence (eg Standard Display Sequence or Alternative Display Sequence) should be flown.

Display Area and Flypast route Hazards. Risks associated with the Display Area and Flypast route are related to the geographic construct of the Display Area and Flypast route, as well as the congestion in both the air and ground space of the Display Area and Flypast route, and the adjacent areas. Crew analysis of the Display Area and Flypast route will assist in determining which Display Sequence (eg Standard Display Sequence or Special Venue Display Sequence) should be flown. Display Area and Flypast route-related pre-flight planning should consider the:

geography, terrain, obstacles (including moveable obstacles such as vessels) and infrastructure

elevation and density altitude

airspace, including:

proximity to controlled airspace, Aerodromes and areas with specific limitations (eg Flight plan requirements or special procedures)

other airspace users (eg scheduled air transport operations)

constraints with Display Sequences (eg parachute displays may restrict flying, ground movement and engine starts)

availability of clear areas in the event of a forced landing or ejection

available support services (eg the provision of ATS)

likelihood of overflight of Spectators and Secondary Spectators, and whether these people are aware of risks

size, audience and priorities of the Air Display and how Display Flying and Flypasts are integrated with the event

presence of livestock and wildlife.

Aircraft-related Hazards. MAOs and UAS Operators should consider the following Aircraft-related Hazards:

configuration, energy, aerodynamic performance and noise

potential emergencies, including

emergencies resulting from mishandled manoeuvres

rotary-wing Aircraft: 
A.         loss-of-power while operating in the avoid area of the height-velocity diagram
B.         loss of tail-rotor effectiveness
C.         vortex ring state

potential debris scatter patterns following collision, CFIT or for Aircraft where compliant airworthiness codes or specifications may not exist (eg WHRA), catastrophic failure

rotor downwash and propeller and jet blast

wake turbulence.

Display Sequence Hazards. The risk posed by the Display Sequence is related to its complexity, the height at which it is flown, and the proximity of the Display Sequence to Spectators and Secondary Spectators. In turn, the complexity of the Display Sequence is proportional to the energy level, and the number and difficulty of, manoeuvres in the sequence. The energy of the Display Sequence is proportional to both Aircraft mass and the square of the true airspeed (eg a heavy Aircraft flying at higher speeds will inherently be performing higher energy sequences). Display Sequence energy considerations are important for determining potential Aircraft debris scatter patterns.

Display Sequence risk considerations should consider the ability of the Aircraft to land outside of areas where Spectators and Secondary Spectators are gathered, in the event of an engine failure or other airborne emergency during a Display Sequence that necessitates a forced landing or ejection.

Fatigue. Display Flying can result in additional physical fatigue and neck muscle strain or injury. Physical fatigue and muscle strain is largely dependent on head movement, and G-forces encountered during Flight. The establishment of Display Flying - specific fatigue control measures (eg training, physical fitness and conditioning programs and duty limitations) will reduce fatigue and injury SFARP.

UAS-related threats. Safety data analysis shows that illegal recreational UAS usage increases in the vicinity of Air Displays, particularly those associated with high-profile public events (eg Australia Day and Anzac Day). Illegal UAS operations at or near an Air Display can present a Hazard to participating Aircraft. Therefore, MAOs and UAS Operators should conduct SRM of the risks posed by illegal UAS operations in the vicinity of Air Displays.

Civilian locations. The ADEO, FDD and Crew should not assume that the same level of controls (eg site preparation and FOD awareness) are in place at civilian locations as there are in military controlled environments. MAOs and UAS Operators should conduct their SRM accordingly.           

GM SPA.30(b)1 – Approval requirements (AUS)

Air Displays require four distinct approvals, as follows:

the 'Authority to Conduct' IAW single-Service policy

the single-Service task Order

the approval of the Flight profile, airspace coordination measures, risk assessment and the required public affairs support to generate community awareness of the profile IAW single-Service policy

FLTAUTH.

MAOs and UAS Operators may consider including Crew training, rehearsal or Competency requirements as a condition of Flypast approval, particularly if the Flypast forms part of a complex Air Display. The Competency requirements may be the same as, or a subset of, the training provided to Display Crew.

Multiple Flypasts in a single sortie. The MAO or UAS Operator may approve multiple Flypasts in a single sortie. The intention is that DASR SPA.30 should not prevent the efficient use of Defence Aircraft for Public Relations (PR) purposes. For example, if an Aircraft transits from Williamtown to the Gold Coast to conduct a PR activity, the MAO has the freedom to approve more than one Flypast for that Aircraft in that Flight.

The MAO or UAS Operator should consider whether the activity constitutes Display Flying if manoeuvres or formation changes to reposition for subsequent Flypasts are conducted in proximity to, and in full view of Spectators. The intent is to prevent a liberal interpretation of the definition of Flypast from alleviating the requirement for appropriate Display Flying risk controls, which are lessons learnt from the 2005 Roulettes accident and the 2019 C-130J near - controlled Flight into terrain (CFIT) incident.

However, Display Flying risk controls are scalable. If for example, additional passes are flown, linked by simple non-dynamic manoeuvring (and where appropriate formation changes) then the required Crew selection, rehearsal, etc is limited. Conversely, for a display of comparable complexity to a Roulette display, then the rehearsal should be comprehensive, the Crew selection demanding, etc.

GM SPA.30(b)2 – Flypast conduct and manoeuvre limitations OIP (AUS)

Aircraft configuration. Configuring the Aircraft in a way that maximises Aircraft performance (eg removing external stores or operating with low fuel loads) can in the event of an emergency, aid in recovery or reduce the likelihood of CFIT. However, where relevant, MAOs and UAS Operators should consider carrying additional fuel where that additional fuel will afford greater protection against structural damage. Similarly, where relevant, MAOs and UAS Operators should consider using configurations that will afford optimal protection against structural damage, for example for C-130J:

effects of secondary fuel management on service life and inspection requirements have not been established; therefore, secondary fuel management should be used advisedly, especially when operating near the gross weight limit for the applicable manoeuvre or airspeed. (AAP 7211.031-1 –  Hercules C-130J-30 Flight Manual refers)

Where practical, MAOs and UAS Operators should remove hazardous materials (HAZMAT) from Aircraft. If this is not practicable, MAOs and UAS Operators should advise first responders of HAZMAT and its location on the Aircraft. Additionally, MAOs and UAS Operators should include HAZMAT considerations in the emergency response plan (ERP).

Speed limitations. MAOs and UAS Operators should consider publishing minimum operating speeds that:

provide sufficient margin above the stall (eg 1.3 times the stall speed for the Aircraft configuration)

enable multi-engine fixed-wing Aircraft to climb away, without change of configuration, if any one engine fails.

GM SPA.30(b)4 – Release of objects and use of ground special effects (AUS)

This regulation requires MAOs and UAS Operators (as the accountable entity) to ensure adequate controls for ground special effects are implemented for Air Displays. However, MAOs and UAS Operators may assign (delegate) responsibility for controlling and coordinating ground special effects to an FDD or external organisation.

Parachuting and airdrop. ADFP 3.9.1 – Airborne Operations Procedures provides guidance on parachuting and airdrop planning, procedures and drop zone requirements, and should be read in conjunction with this regulation.

Dispensing of flares. Falling flares and debris can present additional risks to vessels and marine fauna when dispensed over water. Additionally, Secondary Spectators may mistake the flare release for a distress signal. Therefore, MAOs and UAS Operators should consider the following if dispensing flares over water:

raising a NOTAM

advising the Australian Maritime Safety Authority (AMSA).

Ground special effects. MAOs and UAS Operators should consider the following if using ground special effects during an Air Display:

documenting the location of special effects in Air Display instructions, and including those locations in the pre-Air Display briefing

ensuring the ADEO and the FDD are fully aware of the safety radii and how ground special effects can impact the Air Display

offsetting ground special effects from the Display Line or Flypast route so that Aircraft are not overflying the effects, reducing the likelihood of debris striking the Aircraft

reduction to Aircraft visibility from smoke emitted by ground special effects.

GM SPA.30(c)1i – Crew, FDD and DFS selection

Display Crew and FDD selection. Air Display flying is dynamic; and physically, mentally and emotionally demanding. Manoeuvring in the low-level environment demands skill and focus, plus considerable practice and the right attitude. Display Crew or FDD miscalculation or ill-discipline can have serious consequences for the Display Crew and people on the ground. Therefore, Display Crew and FDD should be aware of, and understand, the responsibilities of their role. Equally, MAOs and UAS Operators should be satisfied that candidates are appropriately skilled and experienced. Appropriate determinants of skill and experience may include:

for Aircraft Captains (AC) and FDD—Category B (Highly Proficient)

for other Crew in multi-crew Aircraft—Category C (Proficient)

hours requirements.

Additionally, MAOs and UAS Operators should consider whether Display Crews and FDDs exhibit the following personal traits:

an ability to manage the pressure inherent in public Air Displays

a high-level of in-Flight situational awareness

humility.

Qualifications and Airmanship. The best hands and feet Pilot in a FEG with the most hours may not be a suitable Display Flying candidate if that individual lacks the judgement to apply the safety philosophies of Display Flying effectively; or lacks the necessary representational qualities. Specifically, Display Crew must understand that the Display Sequence must not be designed or flown to the limits of the aircraft or regulations, such that a disturbance results in an exceedance or violation. Display Crew must understand that they should not compete with the 'ice cream cornetto' for the attention of Spectators—and that to a Spectator a 5G turn on the buffet looks similar to a 4G turn off the buffet; but the 4G turn gives the Display Crew room for corrections so that a small disturbance does not result in a Crowd Line violation or an accelerated stall. Further, without selecting Display Crew from the pool of Aircrew Instructors, the ability to safely train the next Display Crew is curtailed.

DFS selection. DFS should be executive Crew in the MAO’s or UAS Operator’s organisation. However, given the heavy demands on time, particularly during initial Display Crew training, it may be beneficial to appoint non-executive Crew as DFS. Preferably, the DFS should:

be both current on the Aircraft Type and have previous Display Flying experience—ideally on the Aircraft Type

be a FLTAUTHO

exhibit the following personal traits:

personable and with good communication skills, enabling them to provide discreet and firm discussions with Display Crew when necessary

possess strong foundational SRM skills, so as to be perceptive to the inherent risks of Display Flying

demonstrate excellent leadership to engender a safe, yet disciplined Air Display culture.

GM SPA.30(c)1ii – Competency and Currency (AUS)

Competency

Display Crew Competency. MAOs and UAS Operators need not develop a discrete Display Flying LMP. Where Display Crew are trained and assessed as competent to fly the Display Sequences as part of basic or other qualifications, the applicable LMP for this training will suffice.

The ‘knowledge’ component of Display Crew training provides personnel with a common frame of reference and language, and may include topics such as:

Air Display approval requirements

roles and responsibilities of Display Crew, FLTAUTHO, DFS, FDD and ADEO

OIP supporting the planning and execution of Display Flying

Non-Technical Skills (NTS) relating to Display Flying

determining Crowd Lines and lateral safety distances

each manoeuvre in the Standard Display Sequence and Alternative Display Sequence (and Special Venue Display Sequence if applicable), including:

safety gates (eg heights, speeds and Aircraft position relative to the Display Line) and recovery options

adjustments for wind and density altitude

Flight conduct and manoeuvre limitations

decision making in the event of an emergency.

FLTAUTHO Competency. A FLTAUTHO holding a Display Flying Competency may support improved Hazard identification through a better appreciation of considerations relevant to Air Displays, including:

criteria to cease an Air Display manoeuvre; and to not commence or cease an Air Display entirely

Segregation arrangements

environmental aspects (eg elevation and the use of QFE for Display Flying, contrast conditions, weather, visibility)

location and Display Flying specific emergency procedures

Display Sequence complexity, and associated risks and controls

limitations of the FLTAUTH and approval (IAW single-Service policy)

Crew composition, qualifications and Currency.

FLTAUTH technical mastery for FLTAUTHO without Display Flying experience may be achieved through a controlled and progressive process of training and accumulated experience, including:

demonstrated Competency across a spectrum of operations for the Aircraft Type

understanding the elements of the ‘knowledge’ component of Crew Display Flying training

appreciation of the foregoing FLTAUTHO considerations relevant to Air Displays.

FDD Competency. AFHQ AST is the centre of excellence for FDD qualification, training, Currency and supervision. MAOs and UAS Operators should consider liaising with HAS AFHQ if using a non-AST FDD to deliver the Flying Display Supervisor Qualification Course 'in-house'.

MAOs and UAS Operators may consider establishing FDD categories; and restricting the types of Air Displays (eg military-only Air Displays) an FDD may be appointed to—depending on category. If so, it would be appropriate to establish requirements for progression through the categories. UK MAA Regulatory Article (RA) 2335 – Flying Displays, Display Flying, Role Demonstrations and Flypasts provides additional guidance regarding FDD category systems.

Currency

Display Crew Currency. Where Currency has lapsed, MAOs and UAS Operators should consider tailored Display Crew re-currency training—that is a subset of the training provided for initial Display Crew qualification. For example, a recently lapsed Currency may be regained through skills-based re-currency training only. Whereas, a Currency that has long lapsed, may require both knowledge and skills-based training and reassessment.

An exemplar method for Display Crew to regain Currency is that if the Display Crew has not performed a Display Sequence in the preceding:

31 to 60 days, the Display Crew conduct a Display Sequence at the:

relevant approved minima plus 500 feet, and then

relevant approved minima.

60 days, the Display Crew conduct a Display Sequence at the: 

relevant approved minima plus 1000 feet, and then

relevant approved minima plus 500 feet, and then

relevant approved minima.

Display Crew Currency requirements may differ across Crew positions.

FDD Currency. AFHQ AST is the centre of excellence for FDD qualification, training, Currency and supervision. MAOs and UAS Operators should consider liaising with HAS AFHQ when determining FDD Currency requirements and re-currency training requirements.

The two year FDD Currency allows the MAO or UAS Operator to set appropriate compliance periods and aligns with international best practice. However, the MAO or UAS Operator may impose more stringent Currency requirements. FDD participation at an Air Display may not, in itself, be sufficient to retain Currency. MAOs and UAS Operators should consider the minimum functions and roles to be performed at the Air Display to meet FDD Currency. For example, an FDD that only has a supporting role as part of an ADC may not be considered to have met Currency requirements. Similarly, acting as an FDD at an Air Display that only involves Flypasts may be insufficient to meet FDD Currency.

Where Currency has lapsed, MAOs and UAS Operators should consider tailored FDD Currency training that includes a review of planning, organisation and management considerations for Air Displays, as well as supervision and assessment by another current FDD at an Air Display.
 

GM SPA.30(c)2 – Supervision (AUS)

Flight Authorisation. FLTAUTHO should conduct Air Display FLTAUTH in person—to optimise Flying Supervision. DASR ORO.30 includes specific requirements and considerations for FLTAUTH, or changes to FLTAUTH, which are given verbally or via electronic means.

FLTAUTH includes oversight of the full spectrum of the Air Display. However, emphasising the following Air Display elements will enhance the effectiveness of the FLTAUTH process:

adherence to minima and safety gates (eg heights, speeds and Aircraft position relative to the Display Line)

contingency and emergency procedures

Display Crew decision making, including:

the use of SRM to support decisions

key decision points for transitioning from the Standard Display Sequence to the Alternative Display Sequence or Special Venue Display Sequences, or for cancelling the Air Display

the Display Crew’s primacy in making any cancellation decisions (vice ADEO, FDD and DFS), that is: 

if the Display Crew identify any trigger to cancel the display (eg poor weather or breakdown in deconfliction) and cancels participation in the Air Display, then no other appointment should attempt to override the Display Crew’s cancellation decision

any responsible appointment (eg FLTAUTHO or FDD) may make a cancellation decision, and the FLTAUTHO or FDD should convey any cancellation messages via two-way communication, such as telephone (before dispatch) or radio when the Flight is in progress (ie cancellation should not be communicated via an informal messaging application) 

NOTE: A 2019 near-CFIT incident during an Air Display in Sydney Harbour highlighted some of the Hazards associated with using an informal messaging application:

The message thread was used by a number of participants who provided weather updates, opinions on the ability of the crew to conduct the display, and advice on how to achieve the display. Notably, the authorising officer was one of those participants. In addition, there were increasing communications about the need to make a decision on whether the Aircraft would be able to conduct the display, given the weather…

…The informal nature of the communications introduced misunderstandings ([eg] the differing understanding of the AC and the authorising officer with respect to the special VFR approval), and ambiguity. It is possible that the directive tone of some of the authorising officer’s messages influenced the crew to subconsciously defer the decision about the display to the authorising officer.

Display Crew workload management in the lead up to and during the Air Display.

FDD and ADC appointment. AFHQ AST is the ADF lead for the provision of FDD. However, MAOs and UAS Operators (as the accountable entity) should ensure the assigned FDD is suitably skilled and experienced to ensure the MAOs' or UAS Operators' Aircraft are operating in a safe and appropriately planned Air Display environment. Note, in meeting the obligation to 'ensure' a suitable FDD is appointed, the MAO or UAS operator does not necessarily have to appoint the FDD. At Defence Air shows, the AFHQ AST will typically appoint the FDD. In this case, the MAO or UAS operator can meet their 'ensure' obligation by confirming that AFHQ AST (or another appropriate organisation) have appointed an FDD (eg through the MAO or UAS Operator’s normal planning and FLTAUTH processes). However, if the MAO or UAS Operator is hosting a Display Flying event (independently of the AFHQ AST) that requires an FDD, then the 'ensure' obligation includes the appointment of that FDD.

The role of the FDD is vital to a complex Air Display—they are responsible for ensuring Defence Aircraft are operating in a safe and appropriately planned Air Display environment, including:

reviewing risk management artefacts to ensure:

validity of nominal conditions, assumptions and limitations

implementation of SRM controls

ensuring that an appropriate ERP is in place

submitting designated airspace change proposals (eg to activate a Temporary Restricted Area (TRA)) and NOTAMS

providing for pre – (and where relevant and feasible post –) Air Display briefings’

scrutinising Display Sequences for compliance with ADEO requirements

coordinating and controlling—and ensuring the safety control discipline of (eg Display Line maintenance)—all Display Sequences

controlling the Defence components of the Air Display programme, including:

cancelling or modifying (in case of adverse weather, or other conditions that directly affect) the Air Display

coordinating pyrotechnics and other ground special effects

enabling CAA inspectors (where applicable) to ensure civil compliance by civil participants

coordinating the completion and submission of post-activity reports.

In the civil context, the CAA appointed FDD holds legal and regulatory accountabilities. At civil events, MAOs and UAS Operators should consider whether a Defence FDD is required to confirm the civilian FDD has undertaken the above planning requirements.

The establishment of an ADC and appointment of an ADC Chair for complex Air Displays will enhance overall coordination and safety of the Air Display, and will enable administrative duties to be distributed among committee members, allowing the Chair to primarily focus on Air Display control. The construct of the ADC will be dependent on the complexity of the Air Display. Ideally, the ADC should comprise suitably experienced FDDs from the various commands displaying at the event, and may be supplemented by ATS and civil representatives. The ADC Chair should delegate FDD tasks, based on expertise and experience of its members.

DFS appointment. The DFS acts as both a mentor to Display Crew, and safety observer for Display Flying training and rehearsals. Display Crew preparation, training and rehearsal requires near continuous supervision. Therefore, in nominating a DFS, MAO-AMs and UAS Operators should be cognisant of, and facilitate the close supervisory requirements of a DFS, particularly during early phases, when continuity, trust and communication are vitally important to the success of the training and rehearsals.

GM SPA.30(c)3i – Display Flying handling notes (AUS)

Planning and execution of manoeuvres and sequences. MAOs and UAS Operators’ handling notes form a consolidated reference for Display Crew. However, handling notes are not intended to replace information in OIP. Rather, handling notes should include information on Air Display ‘domestics’ (eg start, taxi, take-off and recovery procedures) and ‘how to’ plan and fly specific manoeuvres and Display Sequences.

Altimeter setting. Safety data analysis highlights the disastrous consequences that can occur if Display Flying on QNH instead of QFE. Setting QFE for Display Flying enables Display Crews to use the altimeter as the primary height reference throughout the Display Sequence—decreasing Crew workload and increasing height awareness. Display Crew should be aware that setting QFE can introduce new forms of error and hence should be carefully considered. Handling notes should provide sufficient guidance to Display Crew on the Hazards of incorrect altimeter settings, which sub-scale setting to use, when to make sub-scale setting changes, and system checks required following sub-scale setting changes.

GM SPA.30(c)3ii – Approved manoeuvres and Display Sequences (AUS)

The Professional ADF Aviators' Reference Manual (PAARM) provides additional guidance to support the development of safe Display Sequences. However, MAOs and UAS Operators should consider the following when developing and approving Display Sequences:

how weather and the Display Area affect the Display Sequence

the Aircraft and Display Crew capabilities

manoeuvre energy states (eg losing or gaining energy) and the interrelationship with:

turn performance, cornering velocities and energy preservation

height and speeds requirements

safety gates (eg heights, speeds and Aircraft position relative to the Display Line)

linking manoeuvres

the Display Crew’s ability to exit a sequence, or recover the Aircraft in the event of an emergency.

avoiding sustained G or G-reversal

the safe integration of any object release as part of the display (including consideration of relevant failures).

Additionally, while operating Aircraft to the allowable limits of the Flight and performance envelope may provide visually exciting Display Flying, it can also introduce unnecessary risk. For example, reducing bank or G in a turn looks just as tight from the ground as flying a maximum bank or G turn, and the general public are unlikely to detect the difference. However, reducing the G provides a safety margin if the turn needs to be tightened and from the physiological effects of acceleration.

Air Display risk and Display Crew workload increases if Display Sequences are modified while mid-display. Display Crew should not make significant modifications to the Display Sequence airborne (eg changing entry gates for manoeuvres, or adding or substituting manoeuvres). However, Display Crews should make standard adjustments for wind. For example, adjusting the timing of pitch up for vertical manoeuvres; switching Cuban eights and lazy eights for reversal manoeuvres with wind along the Display Line; small angle of bank during looping manoeuvres to compensate for wind across the Display Line. 

Standard Display Sequence. The term 'Standard Display Sequence' does not imply that all Display Crew in any particular MAO must only fly the same sequence. In developing well rounded Display Crew, it is a useful exercise (as part of their Display Crew training) to design and develop a bespoke Display Sequence, consistent with the MAO's or UAS Operator’s OIP and this regulation.

GM SPA.30(c)3iii – Conduct and manoeuvre limitations (AUS)

Briefings and debriefings. At complex Air Displays, officials (eg ADEO or FDD) should circulate in advance, written Air Display instructions containing all operational information relevant to the Air Display. Officials should supplement the written Air Display instructions with a verbal briefing on the day of the Air Display. Officials should (where feasible) conduct a debrief with participants at the conclusion of the Air Display. The purpose of the debrief is to determine any safety, organisational or administrative lessons that may impact Aviation Safety at future Air Displays.

Safety calls. Table 1 includes suggested safety calls that Display Crew, FDD and DFS may use during Display Flying to assist in assessing height and distance, warn of a safety incident (eg minima being breached), or to cease a Display Sequence. Standardising the use of these calls will assist with interoperability during civil and international Air Displays.

Table GM SPA.30(a)3ii-1 – Safety calls

Warning call	Pilot response
‘(Callsign) too low’	‘Roger (callsign)’
‘(Callsign) too close’	‘Roger (callsign)’
Terminate call	Pilot response
‘(Callsign) terminate	‘Terminate (callsign)’
Knock it off call	Pilot response
‘(Callsign) knock it off’	‘Knock it off (callsign)’

The context of safety calls is as follows:

‘Too low’ call. The FDD or DFS should make a ‘too low’ call if they assess that the Display Crew has descended below the minima.

‘Too close’ call. The FDD or DFS should make a ‘too close’ call if they assess that the Display Crew has breached the minimum lateral separation distance.

‘Terminate’ call. The FDD, DFS or Display Crew should make a ‘terminate’ call when there is a requirement to suspend a Display Sequence for a reason other than Display Crew competence (eg intruder Aircraft or birds). At the discretion of both the FDD and the Display Crew, the Display Sequence may be resumed if safe to do so.

‘Knock it off’ or ‘stop’ call. The FDD, DFS or Display Crew should make a ‘knock it off’ call if safety is compromised. Additionally, the FDD or DFS should make a ‘knock it off’ call if a third ‘too low’ or ‘too close’ call is required. Once a ‘knock it off’ call has been made, a Display Sequence should not be resumed.

If a ‘knock it off’ call is directed, the FDD or DFS should confirm the Display Crew understands the reason the call has been made, and consider whether:

an Aviation Safety Report (ASR) should be submitted

the event should be documented in the post-activity report.

Speed limitations. MAOs and UAS Operators should consider publishing minimum operating speeds that:

provide sufficient margin above the stall (eg 1.3 times the stall speed for the Aircraft configuration)

enable multi-engine fixed-wing Aircraft to climb away, without change of configuration, if the critical engine fails.

Display Lines. Displaying Aircraft perform relative to Display Lines which provide Display Crew with a visual reference of the safe lateral separation distance from Spectators. Display Crew and officials should consider using obvious ground features (eg runways) to define Display Lines. Where the Display Line cannot be defined by an obvious ground feature, Display Crew or officials should define Display Lines with visual markers or lighting. Once defined, Display Lines should be annotated on a suitable scale map or image which is included in the written Air Display instructions, and briefed to Display Crews on the day of the Air Display. Display Crews or officials should also note other distracting line features (eg parallel taxiways) which might hamper identification of the intended Display Line.

Avoiding Spectator and Secondary Spectator areas. MAOs and UAS Operators should consider the likelihood of Secondary Spectators gathering outside the designated Spectator Areas, and any effect the Air Display may have on members of the public in the vicinity of the Display Area. MAOs and UAS Operators should consider:

areas likely to be occupied by Secondary Spectators 

the proximity of major roads, railway lines and local infrastructure and how busy they are likely to be during the event.

MAOs and UAS Operators should consider implementing controls to prevent Secondary Spectators gathering in high-risk areas, or if it is not reasonably practical to do so, inform Secondary Spectators of the risk to them.

For Air Displays at locations where Spectator Areas (and concentrations of Secondary Spectators) are on, or expected to be on, both sides of the Display Line, the minimum lateral separation distance between the Display Line and the Crowd Line, should apply on both sides of the Display Line.

Officials. People acting in an official capacity at an Air Display may be required to position between the displaying Aircraft and the Crowd Line. In this case, Display Crew should consider adjusting the Crowd Line to accommodate these exposed officials. Where it is not reasonably practicable to adjust the Crowd Line, officials should be provided a safety briefing to enable appropriate precautions. If on arrival to the Display Area the Display Crew observe officials acting contrary to the safety brief, the Display Crew should cancel or discontinue the Air Display.

Rotor downwash. DSTG modelling 55 demonstrates that downwash from a hovering helicopter varies with Aircraft weight, main rotor diameter, disc loading, wind speed, and funnelling and channelling features. Rotor outwash is proportional to downwash, independent of hover altitude and decays with radial distance from the Aircraft. However, the rate of outwash velocity decay varies with wind speed. The DSTG rotor downwash modelling provides additional guidance to define lateral separation distances.

Airspace Segregation. Ideally, Segregation should exclude all non-participating Aircraft from the Display Area. For example, MAOs and UAS Operators should consider establishing an airspace reservation or temporary restricted area (TRA). However, if this is not reasonably practicable, MAOs and UAS Operators should consider:

employing ATS, Airspace Management or Air Traffic Flow Management to ensure there is deconfliction between displaying Aircraft and all other Aircraft in the Display Area

raising a NOTAM and informing all regular airspace users of the Air Display.

Rehearsals. Rehearsal of the standard manoeuvres and approved Display Sequences reduces Display Crew workload, and increases crew cohesion during Display Flying, collectively improving the ability to mitigate other human performance limitations.

All Display Crew should be involved in all Air Display planning and rehearsals. The Display Crew and DFS may consider developing an Air Display rehearsal programme that defines specific requirements and conditions for each rehearsal event based on the Display Crew experience, the type of Air Display, the Display Sequence and the Display Area. The Display Crew and DFS may consider conducting the final rehearsal at the event location without Spectators, to confirm SRM artefacts are appropriate.

GM SPA.30(c)3iv – Emergency response plans (AUS)

An ERP is an important requirement for Air Displays, providing documented procedures to be followed in the event of an incident or accident. ERP scope is discussed in DASR SMS. However, the ERP for Air Displays should also include:

the requirements for:

on-site emergency services; and where there is a need to augment on-site emergency services

off-site emergency services

the types of occurrences that may require the cancellation of the event

the roles, responsibilities and procedures for:

providing emergency services with the details and locations of incidents or accidents

controlling accident sites, including those involving multiple accident sites

controlling HAZMAT incidents and communicating HAZMAT controls

managing communications—following incidents and accidents—between officials and with Spectators.

MAOs and UAS Operators need not develop a discrete Air Display ERP where other ERP (eg base or unit ERP) document procedures to be followed in the event of an incident or accident at an Air Display.

GM SPA.40.A – Defence Long Range Operations (AUS)

Purpose. The purpose of this regulation is to ensure that additional safety controls to treat the risks of flight operations with an extended flight time to an adequate diversion aerodrome.

Applicability

DLRO applies to fixed wing multi-engine turbine aircraft, operated by Defence, that may carry Defence personnel on long range flights. The approved aircraft Statement of Operating Intent and Usage (SOIU) forms the basis for applicability and the MAO is responsible for determining which aircraft should be managed under DLRO.

Introduction

The DLRO system supports standing risk assessments and approvals for aircraft, based on the Configuration, Role and Environment (CRE), to develop technical and/or operational mitigation strategies. These standing assessments and approvals are valid until a change occurs to the approved CRE or as directed by the MAO.

The premise behind DLRO management strategy is that Defence aviation risks associated with the conduct of long range flights are identified and treated. Defence should consider the various civil practices as potential DLRO risk mitigating strategies where reasonably practicable; however, DLRO management strategy should be flexible and tailored to the Defence context. The end state is the identification, documentation and treatment of risk, with any residual risk being reduced so far as reasonably practicable and retained by the appropriate risk management authority.

Defence is not bound by civil regulation, nor would it be advantageous for Defence to mandate a strict compliance with civil regulation pertaining to long range operations, also known as Extended Diversion Time Operations (EDTO). Implementation of civil regulation may result in unnecessary costs to Defence, potential operational constraints and a potentially false sense of improved safety; however, there are risks associated with long range flights conducted by Defence which can be controlled through appropriate risk management.

DLRO is an extension of the extant Flying Management System (FMS) and therefore a number of the recommended mitigation strategies are expected to be in place. As such, DLRO should be treated as ‘business as usual’ in the context of Defence operations and any approvals should be simple, at the lowest level practicable and integrated into extant risk management systems.

Risk Management

The aim of DLRO is to eliminate or otherwise minimise risks so far as is reasonably practicable (SFARP) to aircraft occupants in the event of an in-flight emergency, and to ensure the delivery of capability and achievement of the mission. This is done through the identification of the DLRO area of operations and the management of DLRO significant events. Analysis is focused towards the risk domains and processes provided within the Defence Aviation Safety Manual (DASM). In identifying any risks associated with the conduct of long range flights, it is important to establish the applicability to aircraft types and the risk context.

Establish the context. For DLRO, this is achieved through review of the following:

The approved aircraft SOIU. This includes an assessment of the approved roles / flight profiles and environment which involve exposure to long range flights and flights which involve significant flight time from adequate aerodromes. Such roles include tactical and strategic transport, VIP transport, Search and Rescue (SAR), Intelligence Surveillance Reconnaissance Command and Control (ISR/C2) and Air to Air Refuelling (AAR). The assessment of the SOIU includes an understanding of the operating environment, either benign or challenging, any hazards associated with the carriage of cargo/dangerous goods and the exposure of risk to aircraft occupants. Consideration should also be given to whether aircraft occupants are aware of any risks, for example civil passengers versus military passengers/crew.

The capabilities, design features and certification basis of the applicable aircraft which includes DLRO significant systems. This includes compliance to contemporary design requirements, including the Authority (DASA) prescribed design requirements, CAA certification of the same or similar type for EDTO, impacts of military modifications to civil derivative aircraft, critical system performance, the capacity of the aircraft to conduct long range operations and Original Equipment Manufacturer (OEM) Instructions for Continuing Airworthiness (ICA).

The conduct of operations and the supporting FMS which includes all relevant OIP.

Risk Identification. Once the context is clearly established, any hazards and associated risks should be identified. Identification of the hazards should consider impacts to the mission, equipment, personnel and the environment. Once the hazards are identified, the risks are determined considering the six risk dimensions – personnel safety, mission, capability, reputation, financial and environment.

Analyse risks. The risks are analysed in terms of likelihood and an assessment of the most credible consequence for each risk dimension. Any existing controls are considered; including analysis of extant OIP and mitigating strategies that should be conducted for aircraft in service.

Identify Reasonable Measures. Controls and mitigating strategies are identified to eliminate or otherwise minimise risk SFARP. This step can establish whether a system of mitigating strategies is required under DLRO, or whether specific risks need to be addressed only.

When selecting controls or mitigating strategies to treat risk, an assessment must be made as to whether the strategy is reasonably practicable and the cost of implementation does not outweigh the benefit or unnecessarily constrain capability or the conduct of the mission. Risk mitigation strategies are designed to preclude an in-flight emergency and should it occur, to protect occupants and capability as follows:

Preclude. Measures to preclude an in-flight emergency are largely technically based. Strategies may include:

Aircraft which are designed, configured and certified in accordance with CAA EDTO requirements and are supported by an associated Type Certificate (TC).

Specific maintenance procedures and training.

Specific aircraft parts control procedures.

Specific condition monitoring programs and on-board health and usage monitoring systems.

Critical system reliability requirements.

The capture and analysis of critical system data across fleets.

The use of a long range operation Minimum Equipment List (MEL).

The implementation of approved aircraft operating limitations.

Protect. Measures to protect in the event of an in-flight emergency are largely operationally based. Strategies include:

Specific flight planning and time-limited system planning.

Access to specific aircraft performance data for all viable aircraft configurations and contingencies.

The conduct of specific aircrew and operational staff training and currency.

The implementation of procedures in OIP.

Use of constant communication, flight-following and ‘real time’ operational planning facilities.

Assessment of alternate aerodrome facilities to cater for diversions.

The implementation of effective Non-Technical Skills (NTS) such as decision making, situation awareness, communication, stress and fatigue management.

Review. The documentation of a risk assessment process forms the basis for a DLRO approval for the respective aircraft type. The MAO is responsible for conducting DLRO risk assessments.

The MAO determines the applicability of DLRO, how risks are managed, the control strategies to be used and the documentation and issue of approvals. The basis for an approval and the associated documentation should include:

A standing risk assessment that contains MAO-endorsed operational and technical assessments, supported if required by Authority (DASA) advice. The standing risk assessment is valid until a change occurs to the approved aircraft CRE.

DLRO threshold times and maximum diversion times are predetermined and should be reflected in OIP. An appropriate threshold time ensures maximum flexibility and capability whilst duly considering safety. A threshold time is based on worst case contingencies, which have been analysed, reviewed and treated under a risk assessment.

The maximum diversion time should factor a suitable allowance for holding, approach and landing. The maximum divesion time should be assessed and nominated by the respective MAO and it must be greater than the nominated threshold time.

The MAO may approve DLRO threshold times based on considerations that include:

Risk assessment based on a judgement of aircraft design, configuration and performance.

Technical advice regarding technical and design considerations, including advice from the relevant initial airworthiness (military design) organisation. Where relevant, reference should be made to the Defence Aviation Safety Design Requirements Manual (DASDRM) .

Nominated threshold time for an aircraft type, based on a system safety analysis that considers the most limiting aircraft system (including the most time limited system) and related system effects.

The nature of operations.

The personnel exposed to the risks.
 

Threshold times and maximum diversion time determinations may be managed as follows:

Within (less than) the approved DLRO threshold time use extant procedures as documented in OIP.

At or above (greater than) the approved DLRO threshold time as detailed in this regulation.

Aircraft specific limitations and type certified data.

Once the risks and associated treatments have been determined, Mission Risk Profiles (MRP) which document aircraft and operational specific risks and mitigation strategies.

OIP that support the predetermined threshold times and risk management strategies. This includes provision of DLRO specific operational manuals, Standing Instructions (SI), ICA, maintenance/logistic manuals and adequate aerodrome information. Information contained in OIP should address any DLRO specific operating limitations, component life limits, MEL, specific maintenance / inspection requirements and any specific aircraft CRE considerations. Where able, consideration should be given to adopting only one management framework that is interchangeable. References to compliance with CAA EDTO approvals should not be documented in OIP, nor should CAA requirements be referred to as ‘related OIP’.

Where MAO decisions may be influenced by technical considerations, including airworthiness design requirements, the interface should be described in the DLRO management system.

Where previously assessed / approved DLRO limits are expected to be exceeded, such as an immediate operational requirement, a specific or ‘one off’ risk assessment / approval should be conducted. This one off assessment should consider all aspects and should be documented in the same manner as a standing risk assessment / approval, noting that such approvals may involve an operational imperative and may be subject to time constraints for development and approval. It is expected that a ‘one off’ assessment / approval is time limited and subject to review as required.

Additional Reference Material

Additional historical background to DLRO is provided in DASA Advisory Circular 004/16 (Objective Id: AB28337244).

GM SPA.50 – Defence navigation approvals (AUS)

GM2 SPA.50(a) – Defence navigation approvals and specifications in context (AUS)

GM1 SPA.50(a) – Defence navigation approvals (AUS)

The DASR requirement for MAOs to obtain approval for all RNP specifications differs from CASA. Under the CASA system an Operator is required to seek approval for a limited number of specifications (RNP AR APCH, and RNP 0.3). Operations under the remaining specifications require the Operator to utilise TSO equipment. However, DASA approvals may not require TSO equipment provided capability, functionality and performance equivalence can be demonstrated. In addition, CASA requires that the Aircraft Flight Manual states that the aircraft is capable of the particular navigation specification—where DASA does not. CASA surveillance includes an annual audit of the Operator’s PBN training program. Whereas, DASA does not require an annual audit of the MAO’s PBN training program.

GM SPA.50(b) – DASA Form 1307- Application for Navigation Specification Approval (AUS)

MAOs should submit a completed DASR Form 1307 for Defence navigation approval requests. DASA assesses the evidence MAOs submit for each specification approval sought against the eligibility requirements. The eligibility requirements include technical and operational components. 

MAOs, that cannot meet Aircraft eligibility requirements outright, may demonstrate alternate compliance via DASR Form 1307. 

GM2 SPA.50(b)1 – Alternate means of demonstrating compliance

Defence aircraft, in particular aircraft which are not civil derivative, will not often be able to achieve strict compliance with the civil PBN and RVSM requirements. In this case, an alternative means of establishing compliance with the civil standards, in which equivalent performance outcomes are demonstrated, may be acceptable to the Authority. These alternate means will achieve an equivalent level of safety and will be implemented through agreed tailoring to the TCB documented by MCRI. See AMC1 to DASR 21.A.17A.

GM1 SPA.50(b)1 – Demonstration of compliance for Aircraft Eligibility (AUS)

If approval is being sought as part of initial Aircraft acquisition, aircraft eligibility will be documented in the aircraft TCB and TCDS when the MTC is issued.  Where a Defence aircraft has not previously been certified for PBN or RVSM, a major change to Type Design will be required, to update the aircraft’s Type Certification Basis (TCB). Supplementation may be required to include equipage requirements, and will be implemented through agreed tailoring. See AMC1 to DASR 21.A.17A.

GM2 SPA.50(b)2 – Navigation database integrity and discrepancies (AUS)

Additional navigation database integrity and discrepancy guidance is available from CASA Civil Aviation Order 20.91 (Instructions and directions for Performance Based Navigation) Instrument 14, of 2 Nov 2018.

GM1 SPA.50(b)2 – Flight Authorisation (FLTAUTH) (AUS)

A Flight Authorisation Officer (FLTAUTHO) who has experience in the navigation Operation being authorised, may support improved hazard identification through a better appreciation of factors affecting such operations, including degraded or failed navigation equipment or aircraft instruments. FLTAUTHOs should self-assess their competency to conduct the FLTAUTH for the Defence navigation Operations being authorised, inclusive of potential abnormal or alternate procedures required. 

GM SPA.50(c) – Defence navigation Operations training and Currency requirements (AUS)

PBN, RVSM and NAT HLA Operations training development supporting material is accessible from the Aviation Operations Supporting Material webpage of the DASA internal website.

GM SPA.55 – Night Vision Imaging System (NVIS) (AUS)

Purpose. (Context) The safe and effective delivery of military aviation capabilities is enhanced by exploiting evolving Night Vision Imaging System (NVIS) technologies. However, these technologies have limitations, particularly in military aviation applications, when used as the primary means of vision for Safety Critical tasks. (Hazard) Aviation Safety can be compromised by an inadequately defined NVIS, or ineffective management of NVIS equipment and operations. (Defence) This regulation requires the MAO or Sponsor to utilise a defined NVIS that ensures Aviation Safety when Night Vision Devices (NVDs) are used as the primary means of vision for Safety Critical tasks.

Applicability. This regulation applies to MAOs or Sponsors operating Aircraft crewed by NVIS-qualified Aircrew (including Mission Crew) utilising NVDs as the primary means of vision while performing Safety Critical tasks—where Safety Critical tasks in the NVIS context include:

Aircraft control (ie managing the Aircraft Flight path) during: taxi, take-off, cruise, in-Flight manoeuvring, approach, and landing

terrain and obstacle avoidance, Aircraft separation, visual navigation, and other tasks where direction, spacing, distance or rate of closure information is obtained from the NVD.

Note: DASR SPA.55 does not apply when any NVIS component is utilised for a non-Safety Critical task (eg as a sensor for targeting or search) where the primary defences against Controlled Flight Into Terrain (CFIT) and collision with other Aircraft are achieved via other means. For example, for operations at or above Area Safe Height (ASH), Lowest Safe Altitude (LSALT) or Minimum Sector Altitude (MSA) the regulatory hazard controls contained with SPA.55 defending against CFIT are not applicable. Similarly, when using height blocks or radar trail to ensure de-confliction between Aircraft, the regulatory hazard controls contained with SPA.55 defending against collision with other Aircraft do not apply.

DASR SPA.55 NVIS-terminology and definitions:

Night aided. Flight at night using NVD.

Night unaided. Flight at night without the use of NVD.

‘NVIS equipment’ includes items such as: NVD, NVD Head Up Display (HUD), optical cueing device, Helmet Mounted Sight and Display (HMSD), and any other aviation night vision enhancing technology or equipment that delivers an image directly, or indirectly (ie from single, multiple or blended sources) to Aircrew.

‘Visual acuity’ is the ability of the eye to distinguish shapes and the details of objects at a given distance (note, use of the term ‘visual acuity’ is synonymous with ‘visual definition’).

GM SPA.55(a)2 – Night Vision Imaging System (NVIS) equipment design (AUS)

The Defence Aviation Safety Design Requirements Manual (DASDRM) prescribes NVIS equipment design and integration requirements, minimum operational performance standards, and key considerations for the introduction of NVIS equipment, or modification of existing configurations. Design requirements for NVIS equipment categorised as Aeronautical Life Support Equipment (ALSE) can be found in the DASDRM Aeronautical Life Support Equipment chapter. Aircraft and aerodrome lighting design requirements are found in the DASDRM Lighting Systems chapter and Aerodrome Design Requirements chapter respectively.

Aircrew NVIS equipment (eg NVG) is categorised as ALSE under the Night Vision Systems domain IAW the DASDRM Aeronautical Life Support Equipment chapter. NVIS ALSE certification and management is regulated through DASR ORO.40. The process for NVIS ALSE certification and approval, will depend on whether the NVIS ALSE is included in the Aircraft’s Type design, as detailed in DASR GM ORO.40.B(1) – Certified ALSE (AUS), or not. NVIS integration requirements (equipment integration with Aircraft and Aircrew) may be included in the DASR 21 Aircraft Type design and certification process, whereas NVIS equipment design (eg NVG) is not normally part of the Aircraft Type design.

GM SPA.55(a)3 – Night Vision Imaging System (NVIS) equipment management (AUS)

NVIS equipment approval and maintenance. The MAO or Sponsor should consider approval of NVIS equipment (eg NVD, helmet, helmet mount and HMSD) for use by Aircrew after a test and evaluation process, including technical assessments IAW standards prescribed by Aeronautical Life Support Logistics Management Unit (ALSLMU). Qualified ALSE personnel should maintain NVIS equipment (designated as ALSE) IAW MAO or Sponsor approved OIP.

NVD pre-Flight checks. Pre-Flight checking of NVD serviceability and calibration (typically by Aircrew) normally involves a serviceability check conducted in a specially fitted darkened room, and a field check (outdoors or in the Aircraft). In the absence of an approved pre-Flight checking facility, NVD pre-Flight checks should be conducted IAW OEM manual(s) and as approved by the MAO or Sponsor. 

Minimum Equipment List (MEL). The MAO or Sponsor may choose to add unserviceability deferral or relief options (if applicable) for NVIS equipment and NVIS-specific Aircraft components into the DASA approved aircraft MEL. 

Eye protection. Where the helmet visor cannot be worn with NVDs, the MAO or Sponsor should consider (IAW RAAF IAM Document-Aviation Medicine for ADF Aircrew, 3rd edition, 2012 AL6) providing Aircrew with alternative NVIS compatible protective eyewear (eg plano safety lenses) to provide eye protection (where feasible). Safety lenses are less likely to shatter during an impact event than non-safety spectacle lenses. The DASDRM ALSE chapter defines the required standards to be met for protective eyewear.

Vision correction. The DHM Vol 2 Part 9 Chapter 10 details the policy and guidelines for selection and use of Aircrew optical aids. RAAF IAM report Guidelines for the Selection and Use of Spectacles and Contact Lenses by Aircrew of 25 July 2016 provides AVMOs and Aircrew with additional guidance on implementation of DHM policy, including optical aids’ integration considerations with ALSE such as NVDs.

NVIS equipment integration with other Personal Protective Equipment (PPE). Defence WHS policy prescribes MAO or Sponsor obligations for the provision of PPE in the workplace. The DASDRM defines the requirements for certification of PPE such as safety goggles, Helicopter Aircrew Respiratory System (HARS), immersion suits, Chemical, Biological, Radiological and Nuclear (CBRN) suits or other protective equipment. If an NVD is to be used in conjunction with PPE, ALSLMU (or other appropriate organisation) should be consulted to inform MAOs and Sponsors about NVD compatibility.

GM SPA.55(a)4 – Night Vision Imaging System (NVIS) integration with the Flying Management System (FMS) (AUS)

When planning NVIS operations with friendly third parties, MAOs and Sponsors should make every practicable effort to coordinate and standardise procedures in an effort to minimise the risk of the third party (inadvertently) introducing a hazard to Aircrew using NVDs, especially during Aircrew performance of a Safety Critical task while using NVDs. The intent of third party coordination procedures is to prevent recurrence of past aviation safety incidents. Third party (eg ship, tanker Aircraft, Aerodrome) use of NVIS-incompatible lighting during critical Flight phases (eg landing approach or Air to Air Refuelling (AAR)) have resulted in the degradation of Aircrew vision, and compromised Aviation Safety. 

When it is not feasible to coordinate with third parties, or attain their cooperation, MAOs or Sponsors should identify and treat NVIS-related hazards from third party interactions in order to eliminate or otherwise minimise risk SFARP.

GM SPA.55(a)4(i) – Night Vision Imaging System (NVIS) Aircrew composition, qualification, Currency and training (AUS)

Crew composition. The MAO or Sponsor should consider the increased safety risk mitigation provided by multi-crew operations (in comparison to single pilot operations) when establishing the minimum Crew for NVIS operation below ASH, LSALT or MSA , or for other high workload tasks. However, the MAO or Sponsor may still approve single-pilot NVIS operations below ASH, LSALT or MSA. Where multi-pilot NVIS operations are mandated, single-pilot Flight below ASH, LSALT or MSA may be continued in an emergency situation, or during a return to base or diversion, following a non-normal situation, where remaining below ASH, LSALT or MSA is considered the safest option.

Qualification, Currency and training. The MAO or Sponsor should consider including physiology and Non-Technical Skills (NTS) associated with NVIS operations in initial and refresher training courses. The MAO or Sponsor should consider the following roles and tasks when setting NVIS qualification, Currency and training requirements:

instruction

formation

low-level or terrain Flight

air drop

air land

air intercepts 

air to air refuelling

weapon employment

helicopter operations such as:

hoisting

confined area approaches

special operations approaches

embarked operations.

Critical Flight phases. The MAO should determine critical Flight phases for their CRE. Critical Flight phases are those in which NVD vision degradation or loss, without prompt and effective treatment, could lead to an adverse safety outcome. Critical Flight phases are higher-risk phases of Flight including taxiing, departure, recovery, low flying, formation manoeuvring, Air to Air Refuelling, tactical manoeuvring, intercepts, combat manoeuvring, and weapons or payload delivery.

Learning Management Plan (LMP). A stand-alone NVIS LMP is not required where NVIS training is incorporated into existing approved LMPs (eg Flying Instructor course, conversion course, or refresher course).

Difference (or gap) training. Differences training may be tailored to the situation, dependent on the scale or impact of system change. However, training should normally consist of both theory (eg self-study, briefs, presentations, or CBT) and practical elements. Significant modifications and equipment changes may require Flight Simulator Training Device (FSTD) or Flight training with an Aircrew Instructor for qualification award.

Prerequisites for NVIS Flight. NVIS operations require Flight Crew to have a solid foundation in Instrument Flying (IF), night unaided flying, and day Flight. IF and night unaided Flight currency is particularly important in case of reversion to unaided Flight or inadvertent entry into IMC. Many tasks performed with NVD (eg low level Flight or formation) may require Aircrew prerequisite qualifications and equivalent task day or night unaided Currency. 

GM SPA.55(a)4(ii) – Night Vision Imaging System (NVIS) Flight Authorisation (AUS)

Flight Authorisation Officer (FLTAUTHO) NVIS qualification may support improved hazard identification through a better appreciation of factors affecting NVIS operations, including: Crew composition, qualifications, Currency, environmental aspects (illumination, contrast conditions, weather and visibility), task complexity, NVIS and supporting systems’ (eg NVD, FLIR, IR searchlight, HMSD, Aircraft lighting) limitations, and associated risks and controls.

Formation flying authorisation. FLTAUTHOs should consider existing Core Risk Profiles (CRP), Mission Risk Profiles (MRP), and Risk Management Plans (RMP) controls, formation complexity, weather, visibility, illumination, Crew composition, NVIS equipment, formation experience and Currency, and contingency plans for loss of visual reference and collision avoidance. Additional procedural controls may be necessary for low illumination conditions.

GM SPA.55(a)4(iii)a – Night Vision Imaging System (NVIS) risk management (AUS)

The MAO or Sponsor should consider (and mitigate where necessary) NVD characteristics and limitations, which may impact NVIS operations, including:

Reduced Field Of View (FOV). NVDs that utilise Image Intensifying Tubes (IITs) can have a significantly reduced FOV (approximately 40° cone) compared to normal unaided FOV (approximately 200° horizontal and 140° vertical). In order to compensate for the significantly reduced NVD FOV, pilots flying aided must increase head movement and scan rates. The Field Of Regard (FOR) may also be reduced compared with unaided flight due to narrow FOV combined with physical limitations of head movement, and may be restricted by cockpit obstructions such as canopy bows, frames, etc.

Visual acuity and contrast. Although visual acuity with NVDs is greater than that obtained unaided at night, NVDs do not turn ‘night into day’. Visual acuity obtained with NVD is approximately 50% less than that which can be obtained with the naked eye in equivalent daytime conditions. This reduced NVD visual acuity can be further degraded by atmospheric and environmental factors (eg illumination, weather, obscurants, and low contrast terrain). Low illumination increases NVD background noise and results in reduced visual acuity as image contrast is reduced. High illumination or exposure to incompatible or bright light sources (visual or IR) can cause image ‘blooming’ or result in activation of automatic gain reduction features, resulting in reduced visual acuity.

Resolution. Resolution is an objective measure of the ability to distinguish a separation between two objects. Resolution decreases with low illumination due to increases in NVD image background noise. This a design limitation of NVDs based primarily on the number of channels in the microchannel plate, optics and inherent video noise. 

Fatigue. In addition to physiological fatigue resulting from night operations, the use of NVIS equipment can result in additional physical fatigue, neck muscle strain or injury, asthenopia (eye fatigue), and headaches. Physical fatigue and muscle strain is largely dependent on NVD weight, position on helmet, head movement, and g-forces encountered during flight. The establishment of NVIS-specific fatigue control measures will support the reduction of fatigue or injury SFARP, and can include training, physical fitness and conditioning programs, adaption, and rest and recovery aided by duty cycle management. Flight time limits for NVIS operations may also vary for Aircraft Type and equipment combinations, and for different roles and tasks. 

Spatial disorientation. The significant reduction (or absence) of peripheral vision when using NVDs (eg NVGs) requires Flight Crew to rely primarily on central (focal) vision for the maintenance of spatial orientation. Flight Crew must consciously process and assimilate information received from the NVD image (including, where applicable, the horizon, Stabilised Horizon Bar or ground reference), flight instruments (ie the instrument panel or HUD) or other Aircrew (eg verbal communication or gestures) in order to maintain, spatial orientation and situation awareness. Flight Crew reliance on focal vision during aided Flight significantly increases their cognitive workload. Flight Crew cognitive processing must be prioritised, between maintaining spatial orientation, and performing other Flight and mission tasks including navigation, communication, maintaining formation, targeting, weapons or payload delivery and threat avoidance.  There is a significant increase in the risk of spatial disorientation-related accidents during night aided Flight, compared with unaided Flight. It is crucial to train Flight Crew in the early recognition, intervention and recovery from spatial disorientation events to mitigate the increased risk of spatial disorientation associated with NVD operations.  Early transition from visual (aided) Flight to instrument Flight (eg following NVD image degradation) is a critical defence in avoiding spatial disorientation. Effective Flight Crew training and competency in instrument flying is crucial to a successful recovery from spatial disorientation.

Reduced depth perception and distance estimation accuracy. Binocular NVD systems are well-known for reduced depth perception and reduced accuracy in distance estimations, particularly for objects at close range. This is primarily due to eye physiology (eg stereopsis) and NVD optical performance, but can also be impacted by a degraded NVD image due to environmental factors (such as illumination and obscurants). Hyper-stereopsis can also result when using indirect (Type II) view NVD imaging systems (eg Top Owl) where the IITs are not aligned directly with the pilot’s eyes. This can create a situation where objects appear closer when viewed through the NVD, or with a slight image shift compared to unaided vision, or to an image provided by other sensors.

Night vision recovery. Following the removal of NVDs, and during transition to unaided flight, human eyes can take several minutes to adapt to ‘natural’ dark conditions. Safe transition from aided to unaided flight is best achieved by allowing sufficient time at a safe Flight altitude, under low workload, for the eyes to adapt.

Hazard identification.  Although NVDs enhance the safety of night operations through increased night vision and situational awareness, NVIS operations also present unique challenges, limitations and hazards compared to day or night unaided operations. The creation of MRPs for specific NVIS roles and tasks will aid identification of NVIS hazards and risks controls required to eliminate, or where not possible, otherwise minimise risk SFARP. The conduct of additional risk assessments before each Flight will aid identification of contextual hazards and will provide an opportunity to implement additional controls. These additional risk assessments would be based on, for example, MRP controls; Crew composition, experience and Currency; knowledge of NVD characteristics and limitations; and environmental and weather conditions for the specific role and task.

Risk assessments. The MAO or Sponsor should consider conducting risk assessments for all NVIS operations. Additional preventative controls may be required for high risk NVIS activities such as those conducted in reduced visibility, low illumination, or in close proximity to terrain and other Aircraft. The MAO’s or Sponsor’s risk assessments should consider:

existing MRPs (including consideration of tactics, techniques and procedures; and other risk controls, employed in similar operations by other Defence and global operators)

illumination variations expected during the task

weather (such as cloud, visibility, obscurants)

terrain features and contrast

Crew composition, NVIS qualifications, experience and Currency

Aircrew fatigue levels as the task progresses

NVD performance

role and task to be conducted, and associated NVIS hazards

Mission complexity

Role Equipment

extant Aircraft unserviceability effects on NVIS operations

Aerodrome and Aircraft lighting requirements

Light discipline and procedures for operations with third parties

emergency procedures.

Environmental threats. NVD performance can be affected by the availability of light or environmental visibility. Any atmospheric condition which absorbs, scatters, or refracts illumination, either before or after it strikes terrain, may reduce the usable energy available to NVGs. Although latest generation NVDs can provide improved performance in low illumination conditions, they still require some available light, favourable atmospheric and environmental conditions, terrain contrast and reflectivity. The MAO or Sponsor should consider the following environmental aspects when planning NVIS operations: 
 

Weather. Light rain, mist and thin fog may be difficult to detect with NVD. These weather phenomena (despite not being visible to pilot on NVD) can reduce depth perception and contrast, affect distance estimation, mask terrain, and mask signs of impending IMC—creating a potential hazard to NVIS operations. Precipitation (eg snow, rain), hail and obscurants (eg fog, dust, and smoke) can also degrade NVD performance and create a hazard to NVIS operations. The MAO or Sponsor should consider the following controls relating to weather when planning NVIS operations:

Preventative controls as follows:

NVD knowledge and pre-Flight planning. NVD performance predictions can be improved during the mission planning stage, through knowledge of:

NVD-specific characteristics and limitations

the prevailing environmental conditions in anticipated operating areas (eg terrain features and contrast)

accurate weather forecasts that include illumination levels and weather (eg cloud amount and level, precipitation, obscurants), and briefings which include consideration of the impacts of forecast conditions on NVD performance

defined weather, visibility and illumination minimums.

In-Flight weather detection and avoidance procedures. As some obscurants and weather cannot be easily detected with NVDs, Aircrew should remain alert to changes or degradation in NVD performance. Weather, visibility or illumination deterioration may be indicated by the presence of halos, scintillation, loss of scene definition, or image degradation. It may be necessary to periodically look under NVDs, or assign a Crew member to periodically scan for weather unaided. Use of weather radar or FLIR will assist in detection and avoidance of rain and thunderstorms.

Cockpit environmental control. Appropriate use of cockpit environmental control systems can assist to minimise NVD fogging. Fogging can occur with exposure to high humidity in a cold soaked cockpit (eg exposure to outside air via the opening of Aircraft doors or windows in-Flight or on the ground). 

Recovery controls as follows:

IFR Aircraft and Aircrew qualified and current in IF

carriage of a cleaning cloth for NVD fogging situations

emergency recovery procedures for inadvertent IMC entry

designated ASH, LSALT, MSA or visual manoeuvring altitudes and procedures

unusual attitude recovery procedures (eg spatial disorientation).

Terrain and obstacles. Visual acuity of terrain and obstacles is dependent on a number of factors, including NVD performance, illumination, in-Flight  meteorological visibility, and contrast and reflectivity of terrain or water. The contrast of terrain being overflown will vary depending on topography and illumination, including cultural lighting and the angle of the moon. Mountainous terrain may be more perceptible than flat terrain with low reflection or low contrast. When flying over low contrast or low reflectivity featureless terrain, or over water, it may be difficult to judge height without reference to a RADALT. Without the use of an IR searchlight or supplemental IR or EO vision system (eg FLIR) it may also be difficult to detect objects and terrain in shadows or in low illumination conditions when flying over low contrast areas. The MAO or Sponsor should consider the following controls relating to terrain and obstacle when planning NVIS operations:

pre-Flight planning to include pre-Flight study of:

terrain features, predicted terrain contrast and shadows, obstacle locations and lighting

route surveys and topographical maps prior to aided low level or terrain Flight 

use of minimum visual manoeuvring altitudes in low illumination conditions

utilising topographical map (electronic or physical) in-Flight 

use of the Automatic Flight Control System (AFCS) (eg autopilot or Flight Directors with RADALT or altitude hold) for over water Flights

use of terrain awareness and avoidance equipment, including: 

RADALT for all operations below ASH, LSALT or MSA, especially for night low level aided Flight over low contrast terrain or over water 

Terrain Awareness and Warning System (TAWS), Enhanced Ground Proximity Warning Systems (EGPWS), Ground Proximity Warning Systems (GPWS), and Ground Collision Avoidance system (GCAS) to provide advance alert and warning of terrain or obstacles

ground mapping and millimetre-wave radar that provide a radar presentation of terrain and reflective obstacles

IR searchlights and landing lights to illuminate terrain ahead of the Aircraft

IR and EO vision systems (eg FLIR)

Synthetic Vision Systems (SVS) or equivalent, to provide a digital terrain graphic on MFD or NVDs

defined scanning techniques, co-ordinated between Crew, scanning for terrain and obstacles while at low level; and including ‘look under’, or intervals of non-flying pilot unaided scan for obstacles (such as LED-lit masts that may be undetected on NVDs)

Crew coordination and communication skills, and defined Aircrew roles and responsibilities during NVIS Safety Critical operations

the application of defined Aircraft performance parameters (eg speed and configuration) to provide emergency terrain or obstacle avoidance manoeuvre capabilities.

terrain threat recognition and recovery training, including:

RADALT minimum height excursion recovery procedures 

TAWS, EGPWS, GPWS, GCAS, caution and warning activation recovery procedures

visual terrain and obstacle threat recovery procedures

IF training, including procedures to recover to ASH, LSALT or MSA when entering IMC from below ASH, LSALT or MSA. 

GM SPA.55(a)4(iii)c – Environmental minimums (AUS)

Minimum weather and visibility. The MAO or Sponsor should consider establishing weather and visibility minimums based on the fundamental requirement for NVIS operations to remain in VMC. Defining weather minimums for the conduct and continuance of NVIS Flights for training and operations will assist to reduce the risk of CFIT, collision, and inadvertent entry into IMC. Night aided Flight should normally be conducted in VMC, clear of cloud, and clear of obscurants (eg fog, smoke, haze, dust) likely to reduce visibility below VMC, or to reduce NVD visual acuity below that required for the safe conduct of the task. 

The MAO or Sponsor should consider defining the environmental conditions for which additional qualifications, Currency, controls, and authorisations are required, and any other limitations for operations in those specified conditions. Aircrew should remain vigilant for signs of deteriorating visibility during Flight and ensure visual conditions remain suitable for NVIS operations, and within authorised limits.

The MAO or Sponsor should therefore consider defining:  

the maximum cloud cover and minimum cloud base for low level or terrain Flight 

limitations and procedures for operating in reduced visibility caused by precipitation (rain, drizzle, snow, hail) or obscurants (mist, fog, dust, sand, smoke, ash, haze)

thunderstorm avoidance criteria.

Considering visual acuity when setting environmental minimums. When establishing environmental minimums, the MAO or Sponsor should consider the effect weather, visibility, illumination and contrast may have on NVD performance, and the resultant visual acuity. Defined minimums increases safety by establishing the parameters of an operating environment to enable the appropriate visual acuity. This enables Aircrew to identify terrain and obstacles with ample time for detection, reaction and avoidance. Defining a minimum visual acuity based on low level operating speed ranges will reduce the threat of CFIT or collision. In most circumstances, visual acuity out to a distance equivalent to a minimum of 30 seconds flight time is sufficient. DASA recommends the following minimum visual acuity:

Helicopter. Minimum of 30 secs flight time based on ground speed, but not less than 800m (0.5nm*) (*rounded up to nearest 0.5nm)

Aeroplane. Minimum of 30 secs flight time based on ground speed, but not less than 5000m (3nm*) (*rounded up to nearest 0.5nm).

Monitoring and maintenance of visual acuity. Aircrew should continuously assess the actual visual acuity experienced airborne to ensure conditions remain safe for NVIS operations. MAO or Sponsor-defined environmental minimums may not guarantee the required visual acuity to safely conduct roles and tasks. Actual visual acuity may be significantly less than anticipated, based on forecast weather, visibility, illumination and contrast conditions. Visual acuity may also be degraded by obscurants such as dust, haze, fog, smoke or sea spray; or NVD performance degradation (eg activation of automatic gain reduction when subjected to bright light sources). Reducing flying speeds with decreasing visual acuity may reduce the risks of CFIT. However, it may not be tactically sound, or may compromise Aircraft manoeuvrability and safety by reducing aerodynamic performance. 

Illumination minimums. Defined minimum illumination levels should support the visual acuity necessary for safe operations of NVIS roles and tasks. Roles and tasks which require a higher degree of Crew skill, or involve elevated risk, may require higher illumination minimums. 

Illumination levels should be determined for the Flight en-route, in the area of operations, and during the period of operation. Illumination level should be categorised (see Table 1 in AMC SPA.55(a)4(iii)c to ensure Aircrew qualifications, Competency and Currency (when combined with anticipated NVD performance) will meet the requirements for the intended operation to be conducted.

Actual conditions in Flight. Actual illumination or light level may be determined by an approved light meter where available. However, Aircrew judgement will be necessary in-Flight, as it is generally impractical to measure illumination levels once airborne. While airborne, Aircrew should ensure illumination levels provide the visual acuity required for safe operation.

Aircraft role or task minimums. The MAO or Sponsor should consider defining minimum weather and illumination required for the following Aircraft roles and tasks (where applicable):

Training. The minimum illumination or night levels required for initial qualification (ab initio), recurrent and refresher training.

Low level or terrain Flight. The minimum weather, visibility and illumination conditions for low level or terrain Flight, including the following considerations: 

Visual acuity. The weather, visibility and illumination combinations to provide the minimum NVD visual acuity to enable terrain or obstacle identification and avoidance. 

Operation in <2 millilux (mlx) illumination. Additional controls (eg use of a visual safe altitude, IR Search light, formation limitations, training Flight limitations) to be considered and applied. 

Formation. The minimum weather, visibility and illumination conditions for formation Flight, including the following considerations:

Visual acuity. The weather, visibility and illumination combinations (including the use of formation lights) to provide the minimum NVD visual acuity to enable Aircraft identification, position keeping and collision avoidance.

Operations in <2mlx illumination. Additional controls (eg formation limitations, reduced formation complexity, procedural controls) to be considered and applied. 

Specialised helicopter operations. IR searchlight and landing light availability and performance should be considered when establishing illumination minimums for low level Flight and approaches. The MAO or Sponsor should consider defining minimum weather, visibility and illumination required for specialised helicopter operations, roles and tasks, such as those with increased risk and requiring additional Aircrew training and skills, including:

low level or terrain Flight

formation

confined area approaches

special operations approaches

embarked operations

hoisting.

GM SPA.55(a)4(iv)a – Night Vision Imaging System (NVIS) low illumination (AUS)

NVGs require natural light (moonlight, starlight, sky glow) or artificial light (searchlights, cultural lights) to produce an image. Weather and illumination will normally be evaluated during Flight planning, immediately pre-Flight, and continuously in-Flight. NVIS operations should not commence, or continue, when actual environmental conditions may compromise Aviation Safety. NVIS ab initio, initial qualification, and refresher training should ideally be conducted in good weather and illumination conditions, thereby allowing trainees to build confidence and competence before being exposed to low illumination or poor weather conditions. Weather limits defined for training should be more conservative than those for operational activities (which are crewed by qualified and current Aircrew, none of whom are under training).

Low illumination level. When defining low illumination levels (below which additional qualification, training or hazard controls are necessary) the MAO or Sponsor should consider the following factors:

NVD performance in low illumination

type of operations conducted using NVDs, and associated risk 

Aircrew experience levels

other aircraft systems and controls in place to support NVIS safety in low illumination conditions. 

GM SPA.55(a)4(iv)b – Normal and emergency procedures (AUS)

The MAO or Sponsor is responsible for the provision of OIP detailing training, policy and procedures for the management of normal and emergency conditions while flying aided. MAO or Sponsor training and procedures should include:

guidance as to whether to remain on NVDs or transition to unaided Flight following defined faults, failures or emergencies

immediate actions (drills) to be conducted following NVD failure (or vision impairment or loss) during critical Flight phases such as take-off, approach, landing and low level Flight.

GM SPA.55(a)4(iv)c – Role and task instructions and limitations (AUS)

When defining instructions and limitations for NVIS Aircraft Type roles and tasks, the MAO or Sponsor should consider the following:

Operations below ASH, LSALT or MSA and low flying. NVIS Low flying operations should be conducted IAW DASR SPA.20, specifically:

Visibility. Minimum visibility should be expressed in metres—not less than VMC. 

Weather. Weather minimums should support the requirement to remain VMC, clear of cloud and in continuous visual contact with the ground or water.

Visual acuity. Minimum visual acuity should enable terrain and obstacle detection and avoidance, providing enough time for Aircrew detection, recognition and avoidance.

Illumination. Minimum illumination (expressed in mlx) should support the requirement for a minimum visual acuity, and include consideration of NVD performance, IR searchlight or landing light performance (where applicable), Aircraft role and Aircrew experience.

Safety altitudes. Definitions, methods for calculation, and use of visual and non-visual safety altitudes during NVIS operations. 

Minimum level. Minimum height permitted above terrain, water or obstacles when using NVDs as the primary means of vision for Safety Critical tasks. 

Degraded Visual Environment (DVE). (Synonymous with Restricted (or Reduced) Visual Operations (RVO)). A DVE is considered conditions that impair the visual orientation of Aircrew during take-off, Flight and landing. DVE includes circumstances wherein weather, obscurants or obstacles impede the ability of Aircrew to see properly or accurately know where they are in relation to surrounding terrain. Conditions include brown-out, white-out, night glare, fog and mist (and any combinations of these). DVE can lead to reduced situation awareness, increased Aircrew workload, and the partial or total loss of aircraft control. Notably, DVE can also occur in circumstances of high illumination but very low contrast–where the NVD spectral response is uniform across the image, and hence not providing any definition to the observer. Examples include operating over vast flat areas (eg over water, featureless terrain or paddocks with uniform texture). In these circumstances, Aircrew can have difficulty discerning height above terrain, and perceiving gradual climb and descent rates, with the potential to compromise obstacle and terrain clearance.

Speed restrictions. Speed flown should allow sufficient reaction time for weather, obstacle, terrain and collision avoidance: while maintaining adequate Aircraft aerodynamic performance.

Navigation tolerance. Navigation criteria, position keeping, required accuracy and tolerances (ie maximum distance allowable off track) for continued NVIS operations below ASH, LSALT or MSA.

Equipment. Minimum Aircraft equipment for Flight below ASH, LSALT or MSA, including low level or terrain Flight, or Flight at defined operational or tactical safety altitudes.

Formation. NVIS low level formation OIP including: 

formation type, composition, positions and limitations

minimum Aircrew complement

minimum visibility and illumination, and procedures in the event of loss of formation visual contact

minimum height above terrain.

Formation. Formation procedures and limitations, including:

Aircraft lights. Use of external lighting such as IR lights, navigation, formation, anti-collision and strobe lights. 

Minimum illumination levels. Minimum illumination levels required for NVIS formation should allow for safe formation join (or rejoin) and position keeping. Formation in low illumination conditions requires consideration of additional risk controls due to the increased potential for collision. 

Formation positions. Day formation positions and procedures should be adapted to account for NVIS limitations such as reduced peripheral vision (narrow FOV), reduced field of regard (FOR), reduced depth perception and difficulty in accurately assessing closure rates. 

Air to Air Refuelling (AAR). Training, policy and procedures for the conduct of AAR with NVDs, including AAR normal and emergency procedures while using NVDs. 

Weapons employment. Procedures and limitations for use of weapons or expendables that may degrade NVD performance (such as IR flares, missiles or high explosive munitions).

Air intercepts (AI) and Air Combat Manoeuvring (ACM). Procedures and limitations for air interception or air combat manoeuvres during NVIS Flight.

Aerodrome, Ship deck, Heliport or other landing zones. Procedures and limitations for each landing site, including:

aerodrome and ATC coordination and lighting requirements

deck landings and integration with ship procedures and NVIS lighting

contingencies and procedures for DVE

confined area landing procedures.

Embarked operations. Integration, policy and procedures for NVIS embarked operations.

Hot refuelling and Forward Arming and Refuelling Point (FARP). Safety protocols, lighting, normal and emergency procedures, and Aircrew and ground Crew and ATC and Rescue and Fire Fighting (RFF) communication and coordination.

Transition procedures. Requirements for the conduct of transition to or from aided Flight at a safe altitude, including minimum altitudes, and goggle-up (donning) or de-goggle (doffing) procedures for normal and emergency conditions.

Lighting. NVIS lighting requirements and configurations for Aircraft interior and exterior, including formation exterior lighting configurations, and controls for contingencies such as light interference from internal (cockpit) or external sources.

Communication. NVIS procedures for Crew communication and coordination, including common terms for use in emergency situations, to avoid miscommunication or delays.