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-   -   Hawker Hunter Crash at Shoreham Airshow (https://www.pprune.org/military-aviation/566533-hawker-hunter-crash-shoreham-airshow.html)

mopardave 5th Feb 2016 22:18


MD, then there are intelligent observers.
Granted PN

MD

Courtney Mil 5th Feb 2016 22:20


Originally Posted by DaveUnwin
BTW, Was the 'chip' comment aimed at me FL?

I don't think so. There are a couple of posters that turn up here with massive chips.

DaveUnwin 5th Feb 2016 22:31

I hope not CM - I certainly never intended to come across that I did. And you make several very valid points - I fully understand why someone still serving in the military would want to be anonymous, for example.

LlamaFarmer 6th Feb 2016 00:48


Originally Posted by Courtney Mil (Post 9260806)
We see plenty of people here that do use their anonymity to get away with all sorts of crap.

When I read posts here by people I don't know I always glance at their profile to see who I'm reading - more often than not, nothing. So I assume they have no relevant credentials and weigh my opinion of their post accordingly.

Some members here are right to remain anonymous; serving military especially. I remain suspicious of those here that I do not know if they disguise themselves for no apparent good reason other being able to post anything they want whilst hiding behind anonymity.


Some people may have a justified fear of reprisal for stating unfavourable things in a public domain. Stuff that if their company management were to see it and identify the person, may jeopardise their career progression in the company. And we all know how small the industry is, word can get around.

It might be perfectly reasonable for someone to withhold their identity, as you note yourself.



I remain anonymous on all the forums I am on... different usernames too as I'm not all that keen on anyone who can access an unsecure forum potentially working out who I am. Having said that I personally know members on most of those forums, and they know me personally and by username.
On here multiple members know who I am, however I don't like the idea that any old person could know, hence some level of anonymity. I'm sure most people are the same, with only a small minority remaining anonymous to be walts and trolls.

PrivtPilotRadarTech 6th Feb 2016 01:36

Disclaimer: Potential jurors in the UK should not read this, though surely you will hear these facts.

Straight from the AAIB report:
[The Hawker Hunter] commenced a gentle climbing right turn to 1,600 ft amsl, executing a Derry turn to the left and then commenced a descending left turn to 200 ft amsl

[The pilot, who will remain nameless] held a valid Display Authorisation (DA), issued by the UK CAA, to display the Hawker Hunter to a minimum height of 100 ft during flypasts and 500 ft during Standard 3 category aerobatic manoeuvres.

The aircraft was taking part in an air display at Shoreham Airport during which it conducted a manoeuvre with both a vertical and rolling component, at the apex of which it was inverted. Following the subsequent descent, the aircraft did not achieve level flight before it struck the westbound carriageway of the A27.

Now for some simple logic.
1. The aircraft descended to 200 ft, though it was not authorized to descend below 500 ft during aerobatic maneuvers.

2. The aerobatic maneuver was deliberately performed over a busy carriageway.

3. It struck the carriageway, which was 500 feet below the minimum authorized altitude.

Draw your own conclusions. That's it. If you'd like to dispute any of those three points, have at it.

Thelma Viaduct 6th Feb 2016 02:16

Ref. 'Experts'

What happens when 'experts' hold opposing opinion/viewpoints???

LlamaFarmer 6th Feb 2016 02:20


Originally Posted by PrivtPilotRadarTech (Post 9260944)
1. The aircraft descended to 200 ft, though it was not authorized to descend below 500 ft during aerobatic maneuvers.

2. The aerobatic maneuver was deliberately performed over a busy carriageway.

3. It struck the carriageway, which was 500 feet below the minimum authorized altitude.

Draw your own conclusions. That's it. If you'd like to dispute any of those three points, have at it.

https://www.screenused.com/images/fe...D_VIDEO-39.jpg

"These are the facts of the case, and they are undisputed."

mrangryofwarlingham 6th Feb 2016 06:12

I dispute your number 2. The 1/4 clover was substantially not flown over any highway / road.
As to whether final stages were "deliberately" flown over the A27, where's your evidence? Is that was the planned sequence shows?

clareprop 6th Feb 2016 08:38

FL- I intended no criticism of your experience or indeed, that of your colleagues. My point was that after very non-scientific research on previous 'case celebre' ranging from tube and bus bombers, street terrorists and child abuse accusations, it would seem that until charges have been made, it's open house on speculation in social media and traditional media reporting - often obtained from police sources as in the Cliff Richard case. To expect any jury to be 100% ignorant of such reporting would be hopeful in the extreme. In the case of Pprune, there is a simple remedy should conversation be deemed too speculative. As yet, Internet Brands have not seen fit to implement it.

PrivtPilotRadarTech 6th Feb 2016 09:22


I dispute your number 2. The 1/4 clover was substantially not flown over any highway / road.
As to whether final stages were "deliberately" flown over the A27, where's your evidence? Is that was the planned sequence shows?
Witness marks on the road prove the crucial part of the maneuver occurred directly over the road. If I'm wrong about that, it will come as a great relief to a lot of people.

As to whether it was deliberate or not- are you serious? Do you think He Who Will Remain Nameless accidentally performed a 1/4 clover, or didn't know where he was when he commenced it?

strake 6th Feb 2016 09:31

PrivtPilotRadarTech

1. Yes but why?

2. So your 'fact' is the pilot arbitrarily decided that the official display line, at 90 degrees to the road, wasn't good enough for him and so deliberately used the road instead?

3. Yes, it crashed there - again, why?

LOMCEVAK 6th Feb 2016 10:11

PrivtPilotRadarTech,

It is permissible to commence an aerobatic manoeuvre from what is technically a 'flypast' from the minimum DA height for flypasts so long as the manoeuvre is not technically 'aerobatic' until passing the DA aerobatic minimum. Therefore, pulling up for a looping manoeuvre from straight and level at 200 ft agl would have been within the regulations so long as the pitch attitude was such that it would not have been considered 'aerobatic' before climbing through 500 ft agl. There are many definitions of what constitutes an aerobatic manoeuvre but in general 60 deg of pitch is probably the most restrictive. Therefore, in the case of the Shoreham accident the 200 ft agl entry height was above the pilot's flypast minimum so the relevant detail is what was the pitch attitude on climbing through 500 ft agl?

Although not relevant to this discussion, the same applies on recovering from looping manoeuvres. CAP 403 states "Descent below the approved aerobatic display height to the approved fly-by height is permitted once certain of capturing the aerobatic display height".

Please note that my comments above are based on being a current DAE for class G aircraft which includes the Hunter. If you require any further details regarding these aspects I suggest that you read CAP 403.

mrangryofwarlingham 6th Feb 2016 10:51

The crucial part. How are you defining crucial ?

Are you saying you think AH was trying to put the hunter down on the road?

Regarding the deliberate performance of 1/4 clover, I did not suggest otherwise.
You're assertion is that it was deliberately performed over a highway.
My point to you is that it substantially wasn't. And something occurred, we know not yet what, but it could be down to the aircraft or the pilot, which meant the aircraft crashed. You have no evidence whatsoever that the pilot deliberately flew the whole manoevure over the A27 or that he deliberately chose the A27 as the crash site.

Tashengurt 6th Feb 2016 11:01

How do witness marks on the road prove the manoeuvre was deliberately flown over it?
That the a/c crashed on the road is, obviously undisputed.

jumpseater 6th Feb 2016 11:22


PPRT Witness marks on the road prove the crucial part of the manoeuvre occurred directly over the road. If I'm wrong about that, it will come as a great relief to a lot of people.
There are no doubt huge sighs of relief all round.

The witness marks on the road show the point the aircraft made contact with the surface, point 'X', they don't show the crucial part of the manoeuvre.

Crucial
Decisive or critical, especially in the success or failure of something.
pivotal, decisive, deciding, determining,

The 'crucial' moment of the flight occurred where all the factors, aircraft type, aircraft perf, technical status, display location, pilot, weather, human factors, men from mars etc etc, coincided to determine that the aircraft would contact the ground at point 'X'. Whether that crucial point occurred on the run in, on the way up, at the top, on the way down, how and why, isn't known (as far as 'we' know) yet.

Courtney Mil 6th Feb 2016 11:23


Originally Posted by privtpilotradartech
Now for some simple logic.

1. The aircraft descended to 200 ft, though it was not authorized to descend below 500 ft during aerobatic maneuvers.

2. The aerobatic maneuver was deliberately performed over a busy carriageway.

3. It struck the carriageway, which was 500 feet below the minimum authorized altitude.

Draw your own conclusions. That's it. If you'd like to dispute any of those three points, have at it.

Now for some simple facts.

1. By joining the blood fest late and not bothering to read what has already been discussed and explained at length in this forum and more recently in this thread, you have neatly demonstrated the pitfalls of using a single reference without understanding the facts. 15 Sep 2015: "The 100'/500' minima are normal in DAs and as this was a vertical manouver, the pilot would expect to reach gate height for a vertical recovery by 500' ." 14 Sep 2015: "There is a miscomprehention around minimum fly by altitude and minimum aerobatic altitude. Convert to "agl" or "qfe" as you need. The run in was legal according to current regs and there is allowance for pulling up from there into a defined aerobatic manoeuvre." 14 Sep 2015: "The display regulations would allow a 100 foot fly past to pull up into an aerobatic manoeuvre and, therefore, there is nothing wrong with the entry, provided the FDD, CAA or the pilot's DAE had not imposed additional restrictions." The physics of entering the manoeuvre from below exit height are both simple and previously explained. So your point 1 is not relevant unless other evidence is published to indicate otherwise.

2. There were local restrictions in place, but not displaying over the A27 was not one of them, as far as we know. Again diagrams of restrictions imposed by the FDD have been posted on this forum months ago. From your reference, there is no evidence to suggest that your point 2 contravened any DA or local restrictions.

3. Stating that an aircraft crashed below the display minimum height, whilst true, is not the point. The obvious question that is at the centre of the ongoing investigation is why the aircraft descended below the display minimum and ultimately struck the ground - mechanical/structural failure, human error or other factors yet to be determined.

Therefore, no conclusions to be drawn at this stage.

Pittsextra 6th Feb 2016 11:35


LOMCEVAK posted: Therefore, pulling up for a looping manoeuvre from straight and level at 200 ft agl would have been within the regulations so long as the pitch attitude was such that it would not have been considered 'aerobatic' before climbing through 500 ft agl. There are many definitions of what constitutes an aerobatic manoeuvre but in general 60 deg of pitch is probably the most restrictive.
I don't take any issue with what you say but it does throw up a number of reasonably foreseeable issues.

Not least of which is how does the pilot accurately judge his pitch angle? Certainly not by looking straight ahead. So he has his head out looking at the wing tip and really just having a punt. Then he needs to look in at the Altimeter... Really? More likely its a timing and practice thing of pulling "this" quickly... Except not really the type to be doing a lot of practice in is it?

So one question is what was the plan and how was that factored into the build up and what were the abort points??

Does he throw it away if he does pull too quickly and achieves this visually judged 60deg pitch up at 300, 400, 450ft? Plus of course we must remember the actual figure being flown is a 1/4 clover with the rolling element on the up line. In the first place its slightly unnatural to be waiting until +60deg before commencing the roll but now we need to factor in positioning, because if we have started that too early or too late now we in an altogether different position from that which was planned...

Its not hard to see how the workload in the first half of this can ramp up. It may have been better to put the rolling element on the downline and indeed that is what he had done only a few weeks before at a prior airshow.

Finally what are those persons who have oversight, but are external to the aircraft, what are their visual cues for the on going health of the display?? Again what was the plan?

It is undoubted that the pilot did not deliberately intend to do anything dangerous or wrong and the suggestion that he did is utterly idiotic but you can see how it isn't hard for the best laid plans to go off track and what is the plan then? This debate could ultimately be more about the events in the build up than on the day.

Just a view and regardless of the precise cause of the accident worthy of debate.

Pittsextra 6th Feb 2016 11:41

CM - sorry but this


The physics of entering the manoeuvre from below exit height are both simple and previously explained. So your point 1 is not relevant unless other evidence is published to indicate otherwise.
Is wrong. It is not a simple thing to judge and even less simple to repeat well and accurately. In fact without being horrid the act of rolling an aircraft accurately has been demonstrated with this pilot not to be simple.

By allowing yourself to judge things as "simple" isn't that exactly how we overlook, ignore and not plan for? How many smoking holes have resulted with that attitude?

Pontius 6th Feb 2016 11:43

Starting the pull at 100' you'll be through 500' before you reach 60 degrees nose up, so a moot point really.

Courtney Mil 6th Feb 2016 12:02


Originally Posted by Pitts
It is not a simple thing to judge and even less simple to repeat well and accurately.

And that is why displays are worked out and practiced in advance. Literally hundreds of display sequences include manoeuvres that have different entry and exit heights and speeds. The physics are simple, which is what you quote me as saying. The execution is more difficult, but a planned sequence has numerous pre-defined gates, not just for safety, but also to allow the aircrarft to arrive at the correct point in the sky at the right attitude and airspeed for the next part of the sequence.

Display flying requires a great deal of judgement, but flying a consistant sequence also requires the pilot to follow his plan. If you think that the pilot just makes it up on the day and thinks, "I'll start from a height below my exit height this time so I'll add a few knots" then you are mistaken and know even less about the subject than you previously stated and demonstrated.

To recap from earlier discussion, if you want to lower the entry height but maintain the same exit height, you must inclease the entry speed by a known amount - pre-determined when designing the display - adjust the pull on the way up. In the case of this sequence, you may have seen earlier that this manoeuvre was planned to flow from a low pass into a manoeuvre with a vertaical component, so was always planned with a lower entry height and was flown that way during practice, approval and numerous displays.

As your reply above takes my quote about physics and then refers purely to the judgement required I must conclude that you either didn't read what you quoted properly or you were just looking for something to argue with.


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