E' indispensabile un "training" specifico! Le investigazioni negli incidenti aerei hanno inquadrato da tempo la combinazione tra la fatica operativa e percezione della realtà e degli eventi operativi nelle fasi cruciali del volo: quelle nelle quali si registra circa l'80% degli incidenti. Nelle fasi in prossimità del suolo e a terra. Nella fase di accelerazione in pista, in decollo e in avvicinamento per l'atterraggio.
Le analisi riguardanti "Operator’s Guide to Human Factors in Aviation" e le "Human Performance and Limitations" hanno focalizzato le cosiddette "Managing Visual Somatogravic Illusions".
Lo studio nel corso di prove, test nel simulatori di volo avrebbero evidenziato la potenzialità letale di tali "comportamenti".
Fattori di disorientamento spaziale e errata percezione della posizione e/o del movimento lineare o angolare di un soggetto rispetto al piano della superficie terrestre sono di origine fisiologica e rimandano a illusioni visive, vestibolari. Si associano e determinano processi psicologici che innescano processi decisionali, e mentali, controllo operazionale e - talora - un sovraccarico nelle mansioni professionali espletate.
Il 21% degli incidenti avvenuti nella fase di avvicinamento-e-atterraggio sarebbero stati innescati - cause e concause - da situazioni scaturite da "disorientation or visual illusion".
Il "somatogravic illusions risk" sembrerebbe diventata, in "airline aviation" una emergenza da affrontare urgentemente. Vedi articoli e convegni ne l panorama internazionale della "Safety Aviation".
Le problematiche negative associate qualora non adeguatamente identificate e fronteggiate da precise procedure operative innescano riscontri sulla percezione-comportamento dei piloti, e sarebbero ascrivibili, tra l'altro a:
Gravito-inertial acceleration
The gravito-inertial acceleration (GIA) is the vector sum of the vector of gravitational acceleration (upward) and all other linear accelerations acting on the head
Somatogravic illusion
A somatogravic illusion is a false sensation of body tilt that results from perceiving as vertical the direction of non-vertical gravito-inertial acceleration or force
Somatogravic illusion during takeoff
The somatogravic illusion of ‘nose-up’ sensation after takeoff and the erroneous correction of the pilot to push the yoke forward has caused more than a dozen airline crashes
An aircraft accelerating from 170 to 200 knots over a period of 10 seconds just after takeoff, generates +0.16 G on the pilot
The GIA is only 1.01 G
The corresponding sensation is 9 degrees ‘nose up’
When no visual cues are present and the instruments are ignored, an unwary pilot might push the nose down and crash
Somatogravic illusion during final approach
An inexperienced pilot may perceive deceleration due to lowering the flaps as a steep nose-down sensation
On the runway, before the nose wheel touches down, the deceleration may be perceived as a too-low vertical attitude.
An erroneous correction to bring the nose up may cause damage
Caution
21 percent of approach-and-landing accidents involved disorientation or visual illusion
Flying in the simulator can provoke some of these illusions, but the GIA never exceeds 1 G and can not mimic the somatogravic illusion of false nose-up sensation due to acceleration or nose- down one due to deceleration
Conclusion
Would the best pilots be those who have no ‘misleading’ vestibular organ?
No, because they would not be able to stabilize their gaze to read the instruments
However, being aware of the misleading information of the vestibular organ is crucial; humans are not designed to fly
Debrief on your erroneous perceptions and realize that it is a perfectly human and normal sensation (we can’t help it). But, it is not suitable for flying
Confidence, competence and currency in instrument flying greatly reduces the risk of disorientation
Prioritize the workload; first fly the aircraft, then do everything else
Build up experience controlling the aircraft in an environment of conflicting orientation cues
Avoid disorientation by making frequent instrument cross-checks, even when the autopilot is on
Match the instrument readings with your internal mental representation of the flight path
Recover from disorientation by:
•Making the instruments read right, regardless of your sensation
Don’t trust your built-in equilibrium organs, particularly in low-visibility conditions
In moments of stress, make decisions based on the instruments; don’t fall back on your instinct or perceptions
Garbage in leads to garbage out.
The human equilibrium system is designed to function on land, to chase animals… not to fly aircraft.
data inserimento: Martedì 23 Agosto 2016