Recommendations To Enhance Spatial Disorientation Training

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Recommendations To Enhance Spatial Disorientation Training

Transcript Of Recommendations To Enhance Spatial Disorientation Training


DCIEM No. 98-R-32


B. Cheung

Defence and Civil Institute of Environmental Medicine 1133 Sheppard Avenue West, P.O. Box 2000 Toronto, Ontario Canada M3M 3B9

© HER MAJESTY THE QUEEN IN RIGHT OF CANADA (1998) as represented by the Minister of National Defence
© SA MAJESTE LA REINE EN DROIT DU CANADA (1998) Defense Nationale Canada


Approved for public release} Distribution Unlimited __


Executive Summary
Spatial disorientation (SD) in flight wastes millions of dollars worth of defence capability and continues to kill aircrew. A number of CF (Canadian Forces) surveys have identified SD as the most detrimental of all listed aircraft and human factor issues in terms of its effects on flight safety and operational effectiveness. Two retrospective studies by Hartzell and Cheung et al. confirmed that SD was a significant contributing factor in 12 (between 1968-78) and 14 (between 1982-92) accidents respectively. Following a series of SD implicated mishaps in the CF-18 between 1986-90; the Commander of AIRCOM directed the initiation of ground-based disorientation training and the acquisition of an effective ground-based SD trainer. However, without a recent mishap, on-going fiscal restraint and other factors, the support and resources for acquiring an effective ground-based trainer are not available. In order to solve the SD problem, we believe that research on underlying mechanisms is productive and that hardware improvements will eventually provide substantial additional protection. Research and technological improvements that deal with SD will require a great deal of effort and money to implement and is a distant goal. For the near term, the only practical approach is to enhance SD awareness training for pilots and should be addressed without delay. This report reviews current SD training practices in the CF, and makes recommendations to enhance spatial disorientation training on the ground and in-flight. It is hoped that this report will generate continued discussions among pilots, aeromedical instructors, flight surgeons and research scientists in maintaining progress towards mounting an attack on SD.
Key words: spatial disorientation, demonstration, training enhancement.

In the Canadian Forces (CF), several surveys have revealed a significant frequency of SD occurrences. Two retrospective studies on aircraft accidents indicated that there were 12 (between 1968-78) and 14 (between 1982-92) accidents in which disorientation was listed as a major contributing factor. To solve the SD problem, we believe that: (1) research on underlying mechanism is productive; (2) hardware improvements will eventually provide substantial additional protection and (3) improved ground-based SD demonstration and training will be useful in the short run. Research and technological initiatives that deal with SD countermeasures will require a great deal of effort and resources to implement. However, SD training enhancements where appropriate, can be readily achieved and should be addressed immediately. This report provides a brief review of SD problems in the CF, current training procedures, and provides recommendations to enhance interim and long-term SD training strategies.

Table of Contents


Executive Summary






Current SD Training in the CF


Summary of Findings


Recommendations to Enhance SD Training for the CF











During peace time, two of the most life threatening aeromedical problems that the air force might encounter is spatial disorientation (SD) and G induced loss of consciousness (G-LOC). For the past 3 decades, Canadian Forces (CF) flight statistics have revealed the significance of spatial disorientation as a contributing factor in aircraft accidents. From 1968-78, there were 12 accidents in which disorientation was listed as a cause factor, which resulted in the total loss of 10 aircraft and the lives of 8 aircrew (1). More recently, two separate CF surveys (2,3) and a CF study (4) have identified SD as the most detrimental of all listed aircraft and human factor issues in terms of its effects on flight safety and operational effectiveness.
• 50% of pilots in 1 Air Division Survey (3) reported disorientation • 48% reported disorientation in the Fighter Group Survey (2) • 44% reported problems with disorientation, of which 10% have
experienced more than three incidents
However, for comparison:
• In 1 Air Division Survey (3), no pilots reported G-LOC, several reported instances of "grey-out"
• In the Fighter Group Survey (2), 11% reported G-LOC incidents, 12% reported grey-out
• In the CF-18 Human Factors study (4), 4% reported G-LOC incidents, 62% reported incidents of G-induced visual decrement.
It seems that most Pilots see no need for improvement in G protection, but a better system would be welcome if available (3).
A retrospective study by Cheung et al. (5) confirmed that SD is a significant contributing factor in about 23% (14/62) of all category A accidents between 1982-1992. Category A accidents is defined as an event when the aircraft is destroyed, declared missing, or damaged beyond economical repair. Eleven of these accidents involved the loss of lives of 16 military and 8 civilian personnel. Disorientation is a factor not limited to flying trainees. It affects experienced pilots as well. SD is a flight safety hazard in all aircraft but is particularly hazardous in single seated aircraft and when combat pilots engage in activities that are known to cause and aggravate disorientation.
Following a series of SD implicated mishaps in the CF18 during the period of 1986-90; the Commander of AIRCOM directed the initiation of ground-based disorientation training for the CF-18 pilots. As an interim solution, pilots were trained on an existing USN disorientation device, the Multi-station

Disorientation Demonstrator (MSDD). The MSDD is a circular platform with a vertical axis of rotation that could accommodate from 1-10 trainees. Each trainee was seated in a circular capsule capable of rotating 90 degrees, relative to the main platform. A projector assembly with identical rotation parameters to those of the main platform provides seven display patterns to the trainee. The purpose of this trainer is to demonstrate some forms of disorientation, which can occur in flight.
The program was not considered to be effective (Memo 3725A-P51CB ALS, 23 September 1996). Specifically, 3 Wing in Bagotville participated in a disorientation course involving the MSDD during 1991-92. The course was considered to be cost ineffective by the pilots due to the mild nature of the disorientation which had no effect on experienced pilots (Memo 3773 3FE12,23 January, 1998).
Efforts have been made to identify an existing disorientation device that meets the Commander's direction. Partly as a result of aggressive marketing, a perception surfaced that disorientation trainers/demonstrators exist commercially and are effective in training pilots against SD in flight without preliminary research. Director General of Aerospace Development (DGAD) was to acquire an Advanced Spatial Disorientation Demonstrator (ASDD), but action was deferred for financial reasons.
However, without a recent mishap (possibly due to fewer squadrons and reduced flying hours), on-going fiscal restraints and other factors, the impetus of support and resources for SD countermeasures are not available. Before the purchase of the CF-18, it was predicted by (then) Maj. W. G. Hartzell that one or more of these aircraft (at the cost of 10 million dollars each in 1979) were likely to be lost in a disorientation incident in the next twenty years (1). As of 1995, Directorate of Flight Safety (DFS) records showed that five CF-18s were lost (at a cost of 38 million dollars each in 1995) in SD-implicated fatal accidents (4).
With the expanding role of helicopters in military aviation, spatial disorientation has become an important factor in rotary-wing flight safety. Helicopters are conducive to the occurrence of disorientation due to their ability to move in any direction, a true three-dimensional flight. SD imposes a particular hazard to rotary-wing operations, which differ in many respects to that experienced by fixed-wing operators. Modern helicopters now are equipped with comparatively sophisticated automated stabilization equipment and improved instrumentation. However, improvements in aircraft design are counterbalanced by the ability to operate in more difficult areas and weather conditions, and by the requirement for aircrews to make use of visual devices such as NVG (Night Vision Goggles) and FLIR (Forward Looking Infra-Red). Also to be considered are the physical limitations likely to be imposed by the use

of aircrew chemical defence ensembles in the future. A survey completed by the US Army revealed that between 1987-1995,30% of all helicopter accidents were considered to have had SD as a major or contributory factor (6).
The CF has found itself on the eve of acquiring a new fleet of modern helicopters; the AW520 Cormorant search and rescue (SAR) helicopters at the cost of $39.5 million each. One or more of these aircraft are likely to be lost in disorientation accidents in the next 10 years. Although one cannot predict that a comprehensive SD training program will prevent this, it seems to be prudent to promote efforts aimed at prevention and training before the next SD mishap. These efforts could reduce the risk of loss of life and military assets.
Research and technological initiatives that deal with SD will require a great deal of effort and money to implement. However training enhancements where appropriate, can be more readily achieved and so should be addressed without delay. This paper attempts to provide some perspective on SD training in the Canadian Forces and to provide recommendations for interim and long term training strategies.

Current SD Training in the CF
Ab Initio aircrew first encountered disorientation training during their Basic Pilot Aeromedical Training program or during HAI (High Altitude Indoctrination) at Canadian Forces School of Aeromedical Training (CFSAT) in Winnipeg. In addition to the didactic lecture, most students are exposed to the Barany chair and Vertigon (please see page 5 for description). Videos and slides on visual illusion and spatial disorientation are also available for presentation to the trainees. These trainees may have very limited flying experience and very likely no experience with disorientation in flight. They are being instructed by Biosciences Officers and Aeromedical Technicians with limited training aid. This seriously limits the value of this aspect of the initial aeromedical training. The next exposure to disorientation training is at CFB Moose Jaw. At the Initial Instrument Test phase of their training, the ground school program provides one hour during which the Flight Surgeon is to provide the last disorientation training that these trainees will receive, and for some, a long way into their careers. After completing the pilot training and receiving their wings, qualified pilots would receive re-certification training scheduled 5 years from initial training. This involves lectures and case histories only. It is recognized that it is more difficult to make this training practical and credible for experienced aircrew if no standardized and realistic SD training is available.
While this problem exists at all flying bases where the Flight Surgeon has a responsibility for aeromedical training which is not well defined. It is more acute at training bases, which have responsibility for giving the aircrew their foundation in the subject of disorientation. In general, the absence of central coordinated control and support for this vital part of aeromedical training is apparent. For example, it must be emphasized that there is no provision in the Tutor Flying Training Program for airborne disorientation training exercises. Classroom training is only a supplement. The Tutor-Manual of Flying Training CFP167 makes reference to disorientation in four locations (sections 6.29,6.34, 6.37, and 13.15). However it does not discuss corrective or preventive measures or airborne disorientation training. Similarly, CFP 167 (2A) Flying Instructors Guide for Undergraduate Pilot Training refers to disorientation very briefly only twice: in the Instrument Mass (Ground) Briefing Outline and in General Night Flying Section. In neither instance is any reference made to airborne practice or prevention. Finally, in the CF-18 How to Fly manual (AL 12/86), SD was mentioned twice (sections 1-33,2-16), again, without reference to prevention or correction.
At the Squadron level, a recent telephone surveys from 16 Flight Safety Officers revealed that SD training is limited to films and videos that are available for viewing during poor weather conditions when flying is not feasible (Memo 3773 3FE12 ALS, 23 January 1998). This type of training environment is not

conducive to SD being perceived as a credible factor to be considered in active flying. All SD flying training is done in an informal atmosphere where experiences were passed on to junior pilots.
Current SD Lectures
Current classroom didactic lectures from CFSAT are very comprehensive. The syllabus is separated into 4 different categories depending on whether the students are pilot trainees, airborne electronic sensor operators or experienced pilots. The objectives are well defined for the instructors. More time could be assigned to certain topics. However, the assessments of the student on the lecture material are not clearly defined. Without some practical demonstration, there is no opportunity to make the theoretical understanding of the problem of SD meaningful. The practical understanding of SD can only come through exposure to visual and vestibular illusions and actual disorientation in the flight environment in a well-planned and controlled manner.
Current classroom discussions are performed by Aeromedical Technicians, Biosciences Officers, and Flight Surgeons. These instructors do not all have a pilot background which makes the discussion of SD difficult. In order to have an in-depth appreciation of SD, the subject of disorientation requires a very high level of practical understanding of flight, flight dynamics, etc. It seems the program would have a greater impact if it were delivered by qualified Pilots or Flight Surgeons with a pilot background.
Current Available Ground-Based Devices for SD Training
1) Barany Chair
The Barany chair is useful for demonstrating to the pilot trainees some very basic vestibular sensations and illusions illustrating the inadequacy of our organs of balance and the dominance of other sensory systems. However, the Barany chair lacks the capability and realism to be useful in SD training with the sophisticated training systems of today, and is of questionable value with experienced aircrew. The inadequacy of the Barany Chair as a spatial disorientation training device has been reported since 1930 (7).
2) Vertigon (Flightmatic Inc., Teterboro, N. J.)
The Vertigon is a demonstrator with a limited range of visual illusions. A Coriolis illusion is induced by having the subject move his head after a sustained rotation about the yaw axis. This illusion is expected to degrade the ability of the pilot to "make the instruments read right" and it was suggested that this exercise induces a useful training effect. If the proper simulated visual scenes are present

and are reacting appropriately to the control stick inputs, the pilot might be convinced that he is actually controlling the motion of the vehicle. However, if the visual scene is removed and the pilot realizes that there are no associated vestibular sensations corresponding to control movements and instrument readings, the pilot will simply become mis-oriented (suffering an orientational illusion). Moreover, it is extremely dangerous for a pilot to be told that he is combating disorientation, when in fact the control inputs are not related to the vehicle motion as sensed by the vestibular cues. Under these circumstances, a false sense of security may be generated. Often the only memory the aircrew had of the Vertigon is the unpleasant motion sickness symptoms as a result of the Coriolis cross-coupling effect.
3) GYRO IPT (Environmental Tectronics Corporation, Southampton, N.J.)
At the time of writing this report, the CF is in the process of acquiring the GYRO IPT (Integrated Physiological Trainer) which is the latest version of the GYRO-1 series of flight simulators with upgrades on the pitch and roll motion capability. The major advantage is purported to be its closed-loop feature that forces the trainee to relate any demonstration to actual flight situations. However due to the limited pitch (+/-15 degrees) and roll (+/- 30 degrees) capability and the lack of planetary rotation, illusions that can be demonstrated are limited to Coriolis cross-coupling and some visual illusion such as autokinesis that can be demonstrated by other means. Autokinesis is the apparent motion of a small stationary light in the dark. The capability of visual illusion demonstration is limited by the small visual field provided by a 21 inch display monitor. Due to the lack of G forces, which normally accompany such illusions in the aircraft, the demonstration of graveyard spiral and graveyard spin will not be convincing. The listing of nystagmus as an illusion is erroneous. Nystagmus (involuntary eye movements) is a physiological response to sustained angular acceleration and deceleration acting on the semicircular canals. The potential of the GYRO IPT as a SD training tool will be limited to the demonstration of some illusions at the undergraduate pilot training level only. It remains to be investigated that the GYRO IPT is more effective than previous demonstrators.
Current In-Flight Training: Unusual Attitude Recovery
There is no standardized in-flight training on SD demonstration nor recovery from SD. Current in-flight training includes the demonstration of unusual attitudes to student Pilots, requiring them to recover the aircraft. The emphasis of the demonstration is on recovery, not the causes or solutions of disorientation. Although some believe that the in-flight training of recovery from unusual attitudes is SD training, this is not entirely correct. If one is to understand it correctly, in an unusual attitude recovery procedure, the Pilot is taught the most efficient method of righting an aircraft, which has been placed in
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