James Doolittle made history on 24 September 1929, when he took off, flew a distance of 20 miles and landed an airplane by instruments alone [1]. The array of instruments included the Sperry Horizon, precursor of the artificial horizon, which still remains the essential instrument for maintaining orientation in flight.
Conventional aviation training primarily aims at enhancing the perceptual-motor skills of piloting such that the pilot senses, recognizes, transforms and manipulates during the flight to ensure stability and precision of flight path control. This is aided by procedural compliance. Sometimes though procedural errors, due to lack of currency, increased workload (due to adverse weather, equipment malfunction or enemy action), or poor judgement (due to situational uncertainty or potential imminent catastrophe), could lead to ‘pilot error’ [2]. The pilot errs, conventionally, whenever the perceptual, judgemental and motor demands exceed (her)his momentary attention capacity. Roscoe stated that ‘typically it occurs when an unexpected event requires a complicated, unplanned, quick sequence of actions…caused by any induced elevation of …workload beyond a pilot’s capacity” [2]. But in disorientation inducing conditions, this is compounded by incorrect/inadequate sensory inputs. And it is here that the pilot training at times is woefully inadequate whenever an ill-fated pilot shifts from Visual Flight Rules (VFR or visual meteorological conditions (VMC) to Instrument Flight Rules (IFR or instrument meteorological conditions (IMC) conditions making (her)him susceptible to spatial disorientation (SD).
It must be highlighted that when it comes to conventional ‘individual’ training of pilots, the closest an aspiring pilot comes to in-flight training akin to SD is an ‘unusual altitude recovery’. The objective of this in-flight exercise is to induce vertigo (horizontal leans) and help trainee pilot develop and test reliance on flight instruments in the presence of strong vestibular cues [3]. The pilot must be aware of situations which could confuse (her)him about the aircraft altitude or performance. Such situations could result from turbulence, vertigo, lost wingman, carelessness or failure to cross-check instruments or suspecting instrument failure [4]. It is here that the dichotomy in pilot training lies – the conventional training by flying schools is restricted to controlling the aircraft during ‘unusual altitude recovery’ [4] and wherever ground based SD training is offered, it remains focussed on human physiology, specifically sensory limitations, especially during IFR with demonstration of likely illusions [5]. The former trains to control the aircraft and the latter, to understand the mechanism of SD and experience of illusions [5]. But neither of the training methods address the vital issue of ‘Decision Making‘ by the pilot faced with an unknown or adverse disorienting situation in flight. What is ignored is as to how does (s-)he react to the evolving situation; and how does the conflicting sensory stimuli compromise (her)his cognitive abilities, in turn, influencing (her)his decision making in controlling the aircraft for a safe flight?
Here it must be emphasized that deficiencies of problem solving in the face of complex problems in humans occur due to: “restricted capacity of human conscious thinking; tendency of humans to guard their feeling of competency and efficacy; weight of the ‘actual problem’; and forgetting” [6]. So also in disorienting situations, it is the decision making that lies at the root of the final outcome. Especially so, since SD is a perceptual conflict between what the instruments are telling and what the body is feeling – drift towards feelings leads to ignoring of the flight parameters and errors in control inputs to set the feelings right, at the peril of safe flight – an inevitable outcome then being a crash.
Coping with SD requires (intuitive) assessment of the situation. This entails “cue encoding, appraisal of plausible goals, expectancy checks and appropriate actions. This is a sophisticated cognitive process involving rapid encoding of stimuli to achieve recognition and classification of situation prototype and then associated retrieval of the matched course of action” [7]. The demands of decision making during disorienting situations are such that each novice has to behave like an expert, because failure to take correct timely action has a heavy prize: (her)his life attached to it, which (s-)he is not aware or conscious about when the situation starts unfolding. In hindsight, accident investigators may say, ‘…only if (s-)he had done this!’ But by then a precious life is lost and an aircraft.
It is also important to understand the vital, but not commonly commented factor in SD related accident investigations is the decision making that resulted in the tragic outcome. A probable reason for such an oversight is that as it “occurs in real, complex, time-compressed, stressful settings” of aviation [8]. Thus it mostly remains conjectural and hence probably not commented upon.
Prevention of disorientation related accidents can be attained by helping pilots maintain their situational awareness. Commonest approach to such an issue is improved designs of display. This however shall still depend upon focal vision, whereas natural orientation is dependent on ambient vision [9]. Another possible approach could be cognition based, using ground based simulators, by enhancing recognition-primed decisions [10], but this is still unexplored territory waiting to be explored!
Reference
1. Roscoe SN, Johnson SL, Williges RC. Display motion relationship. Ch in Aviation Psychology. Roscoe SN (Editor). First edition, Ames: Iowa State University Press; 1980: 68-81
2. Roscoe RN. Cockpit workload, residual attention, and pilot error. Ch in Aviation Psychology. Roscoe SN (Editor). First edition, Ames: Iowa State University Press; 1980: 159-169
3. Roscoe SN, Childs JM. Reliable objective flight checks. Ch in Aviation Psychology. Roscoe SN (Editor). First edition, Ames: Iowa State University Press; 1980: 145-158
4. Welch JF (Editor). Instrument Flying. Chapter in Van Sickle’s Modern Airmanship, 7th Ed. New York: TAB Books 1995; 555-636
5. Braithwaite MG, Ercoline WR, Brown L. Spatial disorientation instruction, demonstration, and training. Ch in Spatial disorientation in aviation. Previc FH, Ercoline WR (Editors). American Institute of Aeronautics and Astronautics; Virginia; 2004: 323-77
6. Schaub H. Decision making in complex situations: Cognitive and motivational limitations. Chapter in Decision making under stress: Emerging themes and application. Flin R, Salas E, Strab M, Martin L (Editors). Aldershot:Ashgate, 1997: 291-300
7. Flin R, Slaven G, Stewart K. Emergency decision making in the offshore oil and gas industry. Human Factors 1996; 38(2): 262-277
8. Salas E, Cannon-Bowers JA. Special Section Preface. Human Factors 1996, 38(2): 191-2
9. Benson AJ. Spatial orientation in flight. Chapter in Ernsting’s Aviation Medicine. Rainford DJ, Gradwell DP (Editors). 4th Ed, Hodder Arnold; London; 2006: 293-306
10. Klein G. Naturalistic decision making. Human Factors 2008; 50(3): 456-460
Acknowledgement Image courtesy Wikimedia Commons