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Newsletters  >  June 2005  >  Reports

"Risk in General Aviation", John Thorpe, GASCo

 Kevin introduced John Thorpe as a key figure in the campaign to reduce aircraft accidents. John originated the CAA Safety Sense talks in buildings ranging from Nissen huts to hangers across the length and breadth of the UK. In his new role as CEO of the General Aviation Safety Council John is continuing his work in highlighting the hazards facing aviators and how to avoid them. A ‘well kent' figure to this writer, John's message remains unchanged from when I first heard him speak many years ago "Learn from the mistakes of others because you won't have time to make them all yourself." John's talks are always simple, humorous and eye opening, condensing great wisdom and experience into a format readily understood. The tragedy is that we pilots are still crashing aircraft for the same reasons as before, not learning from the past. I doubt John will ever be out of a role in promoting aviation safety.

John identified the aircraft with the worst accident record based on fatalities/100,000hrs. Some such as the Pitts and Jodels I would have suspected. Others such as the Rallye and Cessna 182 were more surprising for me. Each of these though has unique handling/performance characteristics that no doubt catch out the unwary. My own favourite twin turned out to have the worst record in the MEP Class – the Cessna 310. I can well remember the opportunity this type gives for unknowingly dumping most of its fuel to the atmosphere by incorrect switch selection. On my first take off in a 310 I was mentally about a mile behind the aircraft due to its vastly better performance over the staid trainers I had been used to. For me though the most surprising discovery from Johns talk was that the Robinson 22 was safer than the Bell Jet Ranger, the reverse of my expectation. Helicopters in general were particularly prone to misfortune in March. The safest aircraft to fly were identified as the Cessna 150 - 172 and Piper 28 - 38 trainers along with the Robin 400.

Geographically Scotland and North Wales were identified as the most hazardous areas to fly in, the high mountains optimising the opportunity for controlled flight into terrain. Low time PPL's were identified as particularly vulnerable but the more experienced pilot with low hours on type was also prone to mishaps. The human interface with accidents was summarised by John noting that ice on wings does not kill anyone. The decision to take off with the ice on the wings does.

John's talk was appreciated by all the audience and proved relevant for each individual's level of experience. We all took away some gems of flight safety that may prove useful sooner than we think. I hope we hear more from John in the future.

Andrew Sayers

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"Medical Aspects of Preventing Accidents", Dr. David Anton

 Dr. David Anton, formerly of the RAF institute of Aviation Medicine at Farnborough is now Managing Partner in a Practice of Occupational Physicians. Whilst the majority of his time is now spent with the RNLI, he has vast experience in the investigation of aviation accidents and has been involved in more than 200 of these.

His lecture began with an explanation that the medical input into accident investigations is much more than answering the question "Was the pilot fit to fly?"

Beginning with the fall of Icarus he demolished some of our preconceptions. Icarus did not fall because the heat of the ever nearer sun melted the wax on his wings, (whatever Ovid may have thought, we know that it gets colder, not hotter with altitude), but because the cold caused a "brittle failure" of the wax.

Moving from classical times to the beginning of modern aviation, medical input to flight safety began with early restraint harness designs, (best of course attached to aircraft structure and not to the pilot's wicker chair). Then there were early attempts at head protection. Auguste Picard's balloonists' helmet doubled as a padded seat when not in use.

Observation studies of head deceleration injuries showed not the simple flexion extension that was expected, but that the neck can actually stretch by 1.5" before it reaches its elastic limit.

Once it became apparent that there were occasions when it may be safer to leave an aircraft than stay in it, ejection devices became part of the area of aviation medical interest. Meticulous recording of all available information, some of which is ephemeral, is the basis for accident investigation. Careful history taking from survivors of ejections (particularly with regard to post traumatic amnesia) and post mortem studies on the less fortunate revealed unexpected head injuries from contact with the knees during the ejection process and from contact with the canopy on separation.

The safety of ejection seats led to a study of the tolerance of the human body to rapid accelerations, and to devices which explosively remove the obstructing canopy before the pilot's head made contact. Even then, the explosive cord used could sometimes separate from the canopy under impact leaving the pilot with an explosive necklace and a difficult decision to make.

One accident discussed in detail was a description of the fatal outcome of a Jaguar ejection, when the pilot was rendered unconscious during the ejection and thus failed to release his parachute on ground contact. The pattern of ante and post mortem skull fracturing suggested that he was alive until he was dragged backwards by his parachute through the uneven rocks downwind of his landing point.

Another detailed investigation showed how the explosive destruction of the canopy on ejection did not prevent the pilot striking his head on the canopy when ejecting in a flat spin with no forward airspeed to blow the canopy debris away.

Survivability of airline crashes was discussed with particular reference to the Kegworth crash and the crashworthiness of passenger seats. Meticulous history taking and recording of injuries by all the trauma centres concerned led to useful information on the benefits of correct brace positioning in the prevention of head injury, and the mechanism of femoral fractures.

Looking to the future, with increasingly complex helmet mounted technology raising questions about how much mass can a pilot's head tolerate and how to distribute it, Dr Anton felt that the interaction between medicine and engineering, so successful at the IAM Farnborough may now be more difficult to achieve.

Despite the fact that lunch was waiting, there was a great deal of interest shown from the floor, and we would all have been happy to listen to Dr Anton's expertise for considerably longer than his allocated time.

Andy Tobias

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"Triage", Mr Ian Martin

 No postprandial nap with lan Martin at the helm. A reward system of chocolate missiles assured an attentive audience! It was the right place and the right time to be reminded of the origins of ATLS as we know it today. The association between the crash of a light aircraft and the efforts of an orthopaedic surgeon in Nebraska in 1976 led to the development of the structured approach adopted today.

It is as easy as ABC but not forgetting D&E: We whizzed through the mass casualty and multiple casualty approach to triage and then to a test of our revitalised skills. Our afternoon was particularly stimulating.

Frankie Walters

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"Shining a Light into the Black Hole of Trauma", Dr Gordon Turnbull, Consultant Psychiatrist

 Gordon's background is as a psychiatrist with an interest in psychotrauma. He also has strong links with aviation initially in the RAF and with the CAA since 1973. This was the last lecture of the day, however anyone looking for a gentle snooze and slide into pre-dinner drinks was sorely disappointed.

His first slide was of a frog emerging from its pond and attaching itself to the underside of a large jet as it takes off. I was not sure of the relevance here until he described himself and psychiatrists in general as late developers in terms of using technology to advance the field of learning. Psychiatrists have clung on to old ideas of symbolism (pond) and only recently hitched a ride on technology Jet aircraft). This new technology for psychiatrists is neuropsychiatry.

Gordon is clearly an advocate of this new thinking and by the end of the lecture I was convinced as well. Combining anatomy, biochemistry and modern scanning techniques has allowed us to 'see' what is happening in the brain during stressful events and mental illness giving much more hard evidence about the changes taking place than Freud and his friends could ever have imagined.

As an illustration of this new discipline he used Post Traumatic Stress Disorder, which fitted in well with the agenda for the day. The detail would be too hard to summarise in a few words and unfair to Gordon's clear and entertaining delivery (you should have been there). What particularly impressed me about this new way of thinking was that not only did it offer an explanation of what has happened to the individual but can offer a practical and sensible approach to treatment and rehabilitation.

As for why taxi drivers have, on average, a larger hippocampus than the rest of us - well, as I said before, you should have been there!

Janet Gibson

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