French investigators have highlighted problems of conflicting interests in ageing pilots, and difficulties in determining medical fitness, after a Douglas DC-3 stalled and recovered at low height during practice for an air show.
The aircraft, flown by its 41-year old co-pilot, had been among a formation of two DC-3s and a leading Dassault MD 315 rehearsing at Meaux-Esbly airfield on 9 July 2022.
As part of the routine the aircraft would split from the formation, north of the airfield, in preparation to descend for a solo pass. At the point of the split, the co-pilot would hand control to the 85-year old captain – the co-owner of the 1943 aircraft, which was operated by the association France DC-3.
But French investigation authority BEA says that, after the handover at about 340ft, the captain had “difficulty with orientation”.
He aborted the descent at about 100ft and commenced a left climbing turn, increasing the bank until the aircraft stalled to the left at about 340ft height. Control was regained at about 100ft.
The flight director terminated the rehearsal, and the captain proceeded to land the aircraft. The demonstration flight, scheduled for the following day, was cancelled.
BEA found that the captain had been declared unfit, owing to medical and sensory issues including hearing impairment, on several occasions in the decade prior to the incident – including mid-February 2022, five months beforehand, based on neurological test results.
But this most recent decision was referred to the civil aviation safety directorate, and the captain given a six-month fitness approval with certain limitations.
BEA states that, although the neurological exam had revealed impaired visual analysis, other higher-level cognitive abilities “obscured” the significance of the findings.
“Difficulties in mentally representing and manipulating complex three-dimensional visual and spatial information can be prohibitive for piloting an aircraft,” it says, “while still allowing for a normal daily life for one’s age.”
Even though the captain’s fitness was declining, BEA says he deferred plans for other DC-3 pilots to succeed him in his position.
Prior to the incident he had “limited” recent experience, the inquiry says, and this problem was exacerbated by tensions within the association – several current and former members had raised concerns about instances of absent-mindedness, disorientation, and anger during disagreements.
The captain testified that there had been recurring tensions with the co-pilot over the previous six years, including her challenging his authority. BEA says the co-pilot had expressed particular doubts about the captain’s fitness to the association’s president two weeks before the incident, referring to omission of checklist items, hearing problems, lapses of attention, and other issues.
BEA says the disagreements with the co-pilot added to anxiety about the flight – the association was struggling to recover from the Covid-19 pandemic – and a “heightened” emotional state “dominated” the captain’s behaviour.
When he took control of the aircraft (F-AZTE) during the rehearsal, the captain’s mental workload “immediately became significant”, it says, and he failed to identify the runway. He turned left and climbed to orient himself, but allowed the airspeed to fall and the bank to increase.
When the aircraft stalled, the co-pilot pushed the control column while the captain also initiated nose-down control and applied power.
BEA says an aeromedical examiner, faced with evidence of decline in an ageing pilot, might be tempted to order “numerous” examinations to justify a decision of unfitness.
But it argues that the core functions of piloting – such as spatial awareness, and the management of multiple tasks – are “generally not thoroughly explored”. Impairment of these functions can compromise flight safety, it adds.
Ageing general aviation pilots might also be encouraged to keep flying, despite difficulties, owing to pressure to continue offering services – such as operating vintage aircraft, or glider towing.
“These pilots generally enjoy a prestigious social status,” says BEA. “This can encourage them to continue their activity even when their experience is no longer sufficient to compensate for their limitations.
“Paradoxically, social pressure as well as the goodwill of aeronautical stakeholders can impair the judgment of these pilots and prevent them from making their own decisions to put an end to their activities.”
