[Ref Flight International Magazine 7-13 Apr 2020]
Loss of control in flight (LOC-I) has, since the late 1990s, been the biggest killer accident category for airlines. LOC-I linked to somatogravic illusion has frequently occurred.
External visual input, if available, is the dominant human sensory input, and it will correct the illusions caused by the reaction of the body’s inner-ear balance organs to a linear acceleration. However, at night or in cloud with no external visual horizon, there is a risk that somatogravic illusion will affect the pilots.
Human factor (limitations) is a factor – it is important for pilots to develop an effective instrument scan, but it is also very difficult because of the need to reject the balance organs’ misleading input.
Rightly, there is a long list of LOC-I accidents in the past two decades that involved more subtle sensory inputs resulting in pilot disorientation leading to disaster.
Aircraft manufacturers’ assumptions about how pilots will react to the unexpected, particularly technical faults or anomalies, are in the safety spotlight in the aftermath of a series of incidents including two fatal Boeing 737 Max crashes.
Flightdeck design, aircraft systems and flight management tools have changed over the past three decades.
In addition, there are changes in pilot education, sourcing, selection and training over the same period.
The European Cockpit Association says that commercial training schools should not only concentrate on training for a licence – training should encompass everything from the initial basic flying skills to the management competencies needed in an airline environment.
For instance, some airlines in most nations are now required to carry out at least a modicum of upset prevention and recovery training (UPRT) in flight simulators. Unfortunately simulators are not good at reproducing sustained acceleration forces, so realism is lacking – it should be conducted in real aerobatic flights.
Poor paired in terms of experience could lead to accidents, according to active crews.
On the other hand, Flight International Magazine conducted an informal poll of professional airline pilots, and it suggests that there was a fair weight of opinion that the poor paired in terms of experience could lead to accidents, because the pilot monitoring (PM) – the captain – should have had sufficient time to pick up on what the pilot flying – the co-pilot – was doing, and to correct it – team member need time to understand what the others are doing due to the gap on experience.
Not sufficient manual-flying experience also is counted!
Also, there is a general uneasiness with the perception that recurrent training does not attempt to compensate for the insidious effect on pilot cognitive and manual skills of operating with high levels of automation almost all the time.
In the USA, some recommend that airlines, in their flight manuals, should indicate when and where, on revenue flights, manual flying may be carried out by pilots to help maintain their handling skills;
In Europe, however, with its denser airspace and stricter rules on where visual flight rules flying may be carried out, manual “flying” practice is basically only available in simulators or base training.
Obviously, different stakeholders have their own opinions, but the only certainty is that airlines are not prepared to throw money at the problem. It looks, therefore, as if aircraft manufacturers are going to have to downgrade their expectations of pilot reactions.
There are various reasons play role in aircraft incident/accident:
- Human factor (limitations) : somatogravic illusion – it is important for pilots to develop an effective instrument scan, but it is also very difficult because of the need to reject the balance organs’ misleading input
- Machine side : Flightdeck design, aircraft systems and flight management tools have changed over the past three decades
- Human side : changes in pilot education, sourcing, selection and training over the same period
- Environment side : Poor paired in terms of experience could lead to accidents
- Organisation side : Not sufficient manual-flying experience due to regulations and restrictions
Airlines need to manage the costs! Therefore, aircraft manufacturers should refine their expectation model on pilot’s reactions