Preventive strategies start with the selection of healthy candidates with normal vestibular function for aviation duties. The trained aircrew should make conscious and concerted efforts to be physically and mentally healthy, and if unwell or under medication – prescribed or self-medicated, must avoid flying under any circumstances for their safety and that of the passengers. In addition, pilots must be indoctrinated about physiological limitations, which may result in different types of illusions. Such an indoctrination is advocated using both didactic lectures and demonstration and training in a SD simulator, if available.
The emphasis of regulators on instrument flying and rating is well justified as a proven preventive tool against SD. Thus pilots should be proficient in instrument flying, so that they can fly in bad weathers effectively. Besides each pilot striving to hone his/her instrument flying skills, this is the responsibility of the operators and supervisors as well, to ensure that pilots are proficient in instrument flying. In addition, particularly for single cockpit pilots, it is advisable that in case of a break in flying, the pilots must fly the first sortie under supervision and care, preferably a day or clear weather sortie.
In addition, aircraft manufacturers, particularly that of military and the small aircraft, must consciously bring in modifications in the aircraft design and display to decrease the incidence of SD in flight. The broad principles for the designers and manufacturers to consider are:-
- Ergonomically sound cockpit layout.
- Provision of Head up display.
- Use of inside-out vs outside-in ADI display
- Fail-safe autopilot.
When SD Strikes: An advice to the Pilots
- Make a positive effort to redirect attention to instruments. Believe in your instruments.
- Do not try to analyse the situation. This may lead to waste of valuable time.
- Maintain instrument scan pattern.
- Make your instruments read right.
- Do not attempt to mix instrument flying (IMF) and flying by visual reference (VMF). Once on instruments, maintain the IMF unless outside visual cues are unambiguous.
- Seek help. Hand over controls to co-pilot if available.
- Vocalize your situation: Tell the ATC, Radar or any other aircraft in vicinity that you are disoriented. They may be able to help.
- Engage autopilot, if available.
- If nothing else works – abandon the aircraft in time, especially in a single/dual cockpit combat aircraft.
- Orientation in Aviation
- Orientation in Aviation: Vision
- Orientation in Aviation: Vestibular Apparatus
- Spatial Disorientation: An Introduction
- Spatial Disorientation – Visual Illusions
- Spatial Disorientation – Vestibular Illusions
1. Ernsting’s Aviation Medicine. Rainford DJ, Gradwell DP (Editors). 4th Edition. Hodder Arnold, London 2006.
2. Fundamentals of Aerospace Medicine. DeHart RL, Davis JR (Editors). 3rd Edition. Lippincott, Williams & Wilkins, Philadelphia 2002.
3. Human Performance & Limitations – JAA ATPL Theoretical Knowledge Manual. 2nd Edition. Jeppesen GmbH, Frankfurt 2001.
Acknowledgement Image courtesy www.freedigitalphotos.net