Shoreham Airshow Crash Trial

[Bob Viking]

Airsound

Thanks for your reply. I suppose it was inevitable they would have looked at previous sorties.

I need to be careful I don’t sound like a stuck record (I’m sure I do already).

You’re absolutely correct that, having not been at the trial, I am not in possession of all the facts. I still cannot believe however that one bad sortie out of 4 or 5 from an ‘experienced’ pilot is definitive evidence of a medical event.

We’ve all had bad days in the cockpit. I would say, circumstantially, that those bad days are/were more prevalent during our earlier days on a particular type.

I would argue that few, if any, of those bad days could be attributed to an instance of oxygen starvation induced CI. But then, who knows? I’m not a doctor.

BV

[RetiredBA/BY]

Originally Posted by LOMCEVAK

A manoeuvre flown in a 200 engine Mark at full throttle should be capable of being flown in exactly the same way and from the same airspeed in an aircraft with a 100 series engine. If it cannot then, in my opinion, insufficient safety margin has been allowed.

Are you really saying that a jet being flown with 10,000 pounds of thrust, at full throttle, can be duplicated by a near identical aircraft using only its max thrust of 7,500 pounds of thrust. Example : pulling up for a loop at say 350 knots and 4 g.with 10 k of thrust will certainly not produce the same speed and dimensions when using only 7.5 k of thrust.

I have never flown a Hunter but the JP3 and 4 had similar thrust variations, 1750 and 2,500 pounds, simply no comparison, particularly in vertical manoeuvres. I find what you say hard to believe.. Perhaps you could explain and at least satisfy my curiosity.

[Big Pistons Forever]

As I understand it before he started the maneuver he was well below the minimum height above ground specified in his authorization and in level 1G un-accelerated flight. How was this not a conscious choice made by the pilot ?

[LOMCEVAK]

Originally Posted by RetiredBA/BY

Are you really saying that a jet being flown with 10,000 pounds of thrust, at full throttle, can be duplicated by a near identical aircraft using only its max thrust of 7,500 pounds of thrust. Example : pulling up for a loop at say 350 knots and 4 g.with 10 k of thrust will certainly not produce the same speed and dimensions when using only 7.5 k of thrust.

I have never flown a Hunter but the JP3 and 4 had similar thrust variations, 1750 and 2,500 pounds, simply no comparison, particularly in vertical manoeuvres. I find what you say hard to believe.. Perhaps you could explain and at least satisfy my curiosity.

For low level looping manoeuvres in a Hunter I entered with sufficient speed and used maximum thrust to exceed the gate height by a comfortable margin and to apex at a mid range speed. If I then flew a version with less thrust available I could either pull the same g and have a slightly lower apex height and lower apex airspeed or I could slacken the pull in the second quarter and make the same apex height with another airspeed reduction. Theoretically, I could enter with the higher thrust version at a lower IAS than I did and make a lower apex height and airspeed, and if I attempted the same pull up profile in a lower powered version the apex height and airspeed could be marginal for safety or even fail to make the Gate Height. However, I never entered loops in a Hunter with so little safety margin with respect to pull up airspeed or thrust; perhaps others did. The only exception to this was that for an upward half loop I was prepared to enter 20 KIAS slower in a large engine version than in a small engine one although with that amount of thrust I never really had to unless the cloudbase was marginal such that I needed an absolute minimum apex height.

With respect to pull-up heights, you can pull up for a loop from the flypast minima on your DA and AH was not below this although air display permissions will restrict the area where you can come below the SERA 500 ft minima. Obviously, if you pull up lower you need more speed to make the same apex height and airspeed.

The videos shown in court of other displays and practises by AH did not, as airsound has said, show any of the critical errors that occurred in the Shoreham accident display. However, they did show errors such as inadvertent airbrake out in the upward half of a loop, infringing display lines etc. As BV has said, we all make mistakes so everything needs to be put into context and in the case of this accident that is very complicated, and simple conclusions relating to potential CI on the accident display cannot, in my opinion, be made based upon the other videos.

The errors listed by Steve Jarvis also need to put into context. Some were errors of judgement such as the pull-up point for the manoeuvre, the angle rolled through etc. Again, these are errors that are easy to make in a display depending on the visual cues available to the pilot. Therefore, whilst there most certainly were some totally inexplicable errors made during this manoeuvre, some can be explained as known HF issues associated with display flying.

One aspect that has been commented upon very little is training related to displaying a Hunter. At the time of the accident CAP403 referred to training for 'escape manoeuvres' only as a ground training 'emergency' item. There was no requirement for a pilot to practise them during training for the award of a DA on a specific type or in a specific category, and no requirement to demonstrate proficiency in them as a requirement for the award of a DA. Unless specific training has been given regarding rolling a swept wing jet at low airspeed and then such a manoeuvre practised a pilot almost certainly would lack confidence in flying a rolling escape manoeuvre in a Hunter at 105 KIAS and, therefore, may be reluctant to do so. The AAIB report indicates clearly that a Hunter in the display configuration flown at Shoreham can be rolled safely at 80 KIAS so flying an escape manoeuvre at Shoreham was totally feasible. The report also indicates that it was possible to extend at least 4 seconds past the apex with a maximum instantaneous performance pull and then still perform a safe rolling escape manoeuvre.

With respect to Gate Heights and the requirement to respect them in looping a swept wing aircraft such as the Hunter, another essential aspect of initial display training for someone whose display experience is mainly on light aeroplanes for which a Gate Height protocol is not applicable for simple looping manoeuvres is to really emphasise this additional requirement and not to use established habit patterns from previous types.

Nothing that I have said above is new with respect to this tragic accident. However, I felt that, perhaps, it was worth refreshing upon some aspects.

Rgds
L

[CAEBr]

Originally Posted by airsound

. Three or four Hunter displays were shown in court, from a combination of internal and external videos. None of the errors was present in any of the displays.

airsound

I'm not a medical expert, but does this not suggest therefore that that particular display routine / aircraft physiological regime was not severe enough to cause AH an issue - under normal circumstances. Therefore, the issue is what made the Shoreham display different? Was it that AH's physiological tolerance was lower for reason or reasons unidentified or was it just a bad day in the office?

[POBJOY]

Surely the main focus of this dreadful incident is who is going to present the evidence of events ' leading' to it for the coroner to assess.

The scenario was indeed avoidable had even the basic rules of both display authorisation, and the display on the day oversight been implemented,

The regulations were in place to prevent such incidents,and yet it appears little attention has been given to their significance.and indeed their failure to prevent the situation on the day.

The actual Display authorisation appears to have been somewhat lacking in its remit, and this was then compounded by the lack of the actual display oversight which failed to alert and indeed stop the proceedings when the basic criteria fell below the requirements. All this took place before the claimed G induced situation and was therefore very relevant to the outcome. The whole point of DA's and a proper visual check on the day is to protect both the public and pilots from such a scenario 'developing' , and is very important where you have a high energy machine operating in a somewhat 'confined' display arena. This thread has well discussed the actual event, and the various 'issues' that occurred, however the coroner may well find that the 'system' itself was lacking in this case, and therefore a better understanding of the situation may arise.

[Caramba]

I am very aware that I am a guest in this Mess, and have only ever had a single flight in a JP (tho regularly fly light aircraft). I have however been an expert witness and was very aware that I had a duty to do the job properly.

It seems that much of the reportage of this trial was lacking in veracity but nevertheless accepted and as such forms the basis of strongly expressed opinion.

So - Lomcevak, Airsound, Legalapproach: “The videos shown in court of other displays and practises by AH did not, as airsound has said, show any of the critical errors that occurred in the Shoreham accident display. However, they did show errors such as inadvertent airbrake out in the upward half of a loop, infringing display lines etc.“

Was it not the case that the suggestion that AH had infringed display lines part of the prosecution’s attempt to characterise AH as cavalier in his approach to flight and display safety? But that the allegations regarding display lines were refuted in court and that the prosecution and one of the expert prosecution witnesses (JW) exposed as not having done their homework properly?

I ask only as a seeker after truth.

Caramba

[Legalapproach]

Caramba - yes

A prosecution expert witness had not researched the permissions properly and in any event, with the exception of the JP incident at Southport, the criticisms related to notional crown lines during practice displays. There were a number of criticisms leveled by the prosecution nearly all of which ended up being binned. In a way it was a shame that many were ditched at an early stage as we had a some interesting video's of the one of the prosecution experts not necessarily adhering to the rules he was using to criticise AH. Showing them would have made for some uncomfortable moments in the witness box.

[airsound]

Before I make any more responses, I would like to reiterate that I am not an FJ pilot, and I am not questioning the undoubted experience levels of several posters here. What I am trying to do is to make sure that the trial evidence that led to AH’s being acquitted is clearly known about and understood.

Easy Street

The sequence of errors is absolutely characteristic of someone who has gone off ‘the plan’, inadvertently or by design, and is devoting an increasing proportion of their mental capacity to getting back on ‘the plan’

Dr Jarvis made the point that, in his wide experience of studying errors by pilots, he’s usually able to discern a reason, or reasons, for them. And that there’s often an initial error that then leads to a series of others - but in such a case they are all linked. In the 23-odd seconds of the errors by AH, he couldn’t find any relationship between the errors. He went on to say that the statistical likelihood of such a series of events was very low, making this a very rare event for which he could find no explanation other than some kind of cognitive impairment.

ES, you also mentioned in passing that ‘going off the plan’ is

not even something you need to be especially experienced to recognise: a first tourist ‘creamie’ QFI is expected to be able to diagnose it

Coincidentally, AH was himself a ‘creamie’ QFI before going to Harriers.

You also mention, about very experienced pilots

If such individuals make fewer such sequences of errors it’s mainly because they’ve learned how to stop the initial (inevitable) error from cascading.

But the point was made in court that the start of the sequence of errors was not in a particularly high workload part of the flight - one of those had just been successfully completed.

Bob Viking

I still cannot believe however that one bad sortie out of 4 or 5 from an ‘experienced’ pilot is definitive evidence of a medical event……[and] few, if any, of those bad days could be attributed to an instance of oxygen starvation induced CI

The defence case was one of ‘cognitive impairment’. A medical event was only one possible cause of that. And oxygen-starved CI was also a ‘may be’.

*****

One interesting aspect of the case was that the prosecution, faced with the convincing evidence of Dr Jarvis, chose not to engage a ‘Human Factors’ expert to challenge him.

airsound

[Treble one]

Thank you Airsound

I'm not a FJ pilot, but I'm a scientist, and I look at things based on evidence and probability. The thing I have most difficulty with here is that I am being asked to believe that all of these things went wrong in 20 seconds or so, caused by an effect no one can fully explain, or indeed prove happened, that 'came on' at exactly the wrong time, when there was no evidence of it ever happening in the individual before, or at any time before the tragic manoeuvre in this flight. That's a very unlucky lining up of holes in a lot of cheese. My antennae are twitching. Because the flying in the accident manoeuvre could also be explained by the actions of an inexperienced pilot on type, who simply got it wrong?

Sorry, that's the scientist in me kicking in. When I hear the clip clop of hooves on the road, I think horses, not zebras.

[Chugalug2]

Originally Posted by Treble one

Sorry, that's the scientist in me kicking in. When I hear the clip clop of hooves on the road, I think horses, not zebras.

Or maybe Coconut shells? I realise that this thread is about the trial and its outcome, but isn't it about time that dissatisfaction with the verdict by some gave way to a more general concern about the overall state of the managing of public display flying in the UK? Many here want to vent their spleen on AH and/or CI because they see them as presaging a crackdown on future display flying (if indeed there be any at all). I agree that a crackdown is likely and may well be called for by the Coroner. May I suggest that many here would have been aware of the organisational shortcomings that have emerged from this tragedy but pre-existed for years beforehand. It is those shortcomings that paved the way to Shoreham and to its tragic outcome. There was gross systemic failure here and like other gross systemic failures revealed within this forum nothing was done to cure it, thus leading to yet more needless death.

[POBJOY]

Systemic Failure

Originally Posted by Chugalug2

There was gross systemic failure here and like other gross systemic failures revealed within this forum nothing was done to cure it, thus leading to yet more needless death.

Well Chug I for one think this is the real problem, and the limited scope of the legal charge that focused only on one person has certainly obscured the 'big picture'.
However does the proposed coroners input allow a wider view of this situation, and can it begin to give the relatives of those involved some indication of how AH was not the only one involved. As I have prev alluded, the display authorisation system was intended to give a greater element of safety control to the display world, was not too onerous to comply with, and not unreasonable in the context that in the norm pilots had to 'perform' in the aircraft of intended display, and demonstrate the manoeuvres intended. To a degree this became even more important as ex military jets came on the scene where pilots may not have the tot time or 'regular' flying on type to be as current compared to what would have been normal when in mil service. When you add display locations that are not 'fast jet friendly' in the case of an emergency landing or ' space' the DA system becomes even more important as especially with the added potential input of a display director*. This position* was not unknown in the display world before the actual formal DA system was instituted, and I well remember the classic Biggin Hill Air Fair events that were basically 'self governing' to a large degree but contained a high degree of oversight by a designated person. Needless to say certain 'jet teams' (not the Reds ) were not always totally compliant with the UK normal accepted rules and I well remember one year when the crowd got well and truly 'Dyed' after a rather low and close run by a certain team although I do not recall any complaints.** Sadly the display world 'as was' will never return in the UK despite it having a very reasonable safety record, and I feel that this is due to the 'System' failing in its duty rather than just an individual getting it wrong on the day. The question is will this be part of a coroners remit !!
** It was not repeated the next day so no doubt words were spoken that evening at the rather splendid party. (this system worked well)

[airsound]

Pobjoy

The question is will this be part of a coroners remit !!

Well, we (and the families) will have about 14 months to wait to find out. But actually, as far as the aviation world, and particularly the air show world, is concerned, the primary safety follow-ups from the accident are surely the AAIB and the CAA. Did the AAIB’s recommendations address your concerns? And the CAA follow up? Which AAIB recommendations might prevent another Shoreham?

airsound

[Chugalug2]

Pobjoy :-

The question is will this be part of a coroners remit !!

Coroners are very individual as to what they see as their 'remit'. Some see it as not making waves, a theme that runs through the British Establishment like a stick of rock. Others see themselves as duty bound to finding out the real reasons why those who are the subject of their investigations died in such a violent way. The Oxford Coroner was very much of the latter persuasion and, though representing an 800 year old institution, had no hesitation in telling one yet to score its first century that there was something wrong with its bloody aircraft, ie that they were unairworthy! As airsound wisely comments we shall just have to wait to find out in this case which 'interested parties' are called to give their evidence and what use is then made of that evidence, but I hope that it is rather more comprehensive than the two organisations he instances and who have so far given us their tuppence-worth.

Meanwhile here is what the Coroners Service says of itself :-

https://assets.publishing.service.go...e-jan-2020.pdf

[POBJOY]

Down to basics

[QUOTE=airsound;10830517]PobjoyWell, we (and the families) will have about 14 months to wait to find out. But actually, as far as the aviation world, and particularly the air show world, is concerned, the primary safety follow-ups from the accident are surely the AAIB and the CAA. Did the AAIB’s recommendations address your concerns? And the CAA follow up? Which AAIB recommendations might prevent another Shoreham?

As i see it the AAIB reported on facts and evidence,and the CAA are part of the 'system' under scrutiny. If we cut through all the 'legal fencing' the one stark fact that sticks out is that the 'primary' cause of the accident was starting a vertical/rolling manoeuvre too low and slow on what was a hot day. The fact that no attempt was made to exit this situation only compounded what was already a poor decision made before any G induced factors were present. The display organisers were empowered to comment on this as part of the standard safety procedure and even if they had no speed readout available the low height was 'observable'. Stones and glasshouses now comes to mind as we all know one of the factors associated with airshows is (no one wants to break off a display),and that is the 'dangerous' part of the scenario, and why there was a system to prevent it. It so happens that i have just re read an excellent book by a former Hunter pilot who only flew the T7 after he finished the Chivenor course.He makes the point that the 'climb' performance of the T7 was considerably less than the single seat version in use at the same time. !!!

[Background Noise]

Originally Posted by POBJOY

The display organisers were empowered to comment on this as part of the standard safety procedure and even if they had no speed readout available the low height was 'observable'.

Can we just put to bed the fallacy that he was 'too low' entering the manoeuvre. This was, and still is, perfectly acceptable. It was explained again by LOMCEVAK and is common practice in both civ and mil displays.

Originally Posted by LOMCEVAK

With respect to pull-up heights, you can pull up for a loop from the flypast minima on your DA and AH was not below this although air display permissions will restrict the area where you can come below the SERA 500 ft minima. Obviously, if you pull up lower you need more speed to make the same apex height and airspeed.

[LOMCEVAK]

Originally Posted by POBJOY

It so happens that i have just re read an excellent book by a former Hunter pilot who only flew the T7 after he finished the Chivenor course.He makes the point that the 'climb' performance of the T7 was considerably less than the single seat version in use at the same time. !!!

You have put 'climb' in inverted commas so it is not clear to precisely what you are referring. But, with respect to T7 performance at the density altitude and mass that G-BXFI had at pull up at Shoreham, an entry at 350 KIAS with full power gives an apex height and airspeed that both are significantly greater than the minima required to complete the second half of a loop safely. The fact that a big engine single seat version has more thrust and so, for the same entry conditions, will apex higher and faster is totally irrelevant. If full T7 power is maintained throughout a looping manoeuvre entered at 350 KIAS at the accident atmospheric and mass conditions and the exit height is the same as entry height then the exit airspeed will be greater than that at entry ie. the aircraft will have gained energy overall. Therefore, as stated in the AAIB report, a Hunter T7 can fly a bent loop perfectly safely if it is entered at 350 KIAS with full power.

[sittingstress]

As a non-flying type please can the term "CI" in the context of this thread be explained to me.

Sorry for the interruption.

[AndoniP]

Originally Posted by sittingstress

As a non-flying type please can the term "CI" in the context of this thread be explained to me.

Sorry for the interruption.

Cognitive Impairment. Basically something the defence put forward as the reason for the crash that the prosecution couldn't disprove. Hadn't happened to him before though.

[Bravo Alpha One]

This dreadfuI event puzzles and disturbs me. I cannot claim any expertise in fast jet aerobatics, but I have had experiences that I wonder might be relevant.
Naturally, experienced pilots speculate that if the accident pilot had become impaired it may have been due to G, or to some sort of oxygen deprivation. However, if I have read things correctly the fatal manoeuvre went wrong right rom the start, way before the onset of G.
There is something else that can do that; a Transient Ischaemic Attack (TIA) - (https://www.nhs.uk/conditions/transi...ic-attack-tia/). This often referred to as a mini-stroke. A TIA is caused by a very small blood clot blocking a small artery in the brain causing various symptoms similar to stroke; the clot then dissolves (if you're lucky) to leave no trace.
I have seen three people suffer from this, their main symptom was confusion and the only one that was actually diagnosed at the time was a friend who crashed his car. He said he had no idea what had happened, he was totally confused, and so investigations were commenced soon after the event thus revealed the cause.