Crash at airshow.

Kodak, a Split S is performed by rolling inverted while in straight and level flight and pulling through a half loop. The result is a 180 degree change in direction, loss of altitude and an increase in airspeed.

True, though a split s can also be performed in a climb rather than straight and level. The now infamous Thunderbirds crash was caused from one, done on take off. It is also referred to a reverse half cuban.

Kodak, a Split S is performed by rolling inverted while in straight and level flight and pulling through a half loop. The result is a 180 degree change in direction, loss of altitude and an increase in airspeed.

Originally posted by RobAnt
So to return to my original question – a Derry Turn & a Derry Roll are the same thing – just spelt differently?

Ive never seen it described as a derry roll, although it is a rolling manouvere. Your initial description sounds correct – its easier to demonstrate than describe!! It can be performed from wings level, i.e pulling up then rolling “under” 270 degrees left or right to exit in the opposite direction. If the aircraft is already in a turn (say) to the right, a 90 degree roll to the right will put the aircraft in the opposite direction, though some will call this a “canadian break”!
I believe that John Derry “invented” the manouvere as the result of display flying, rather than most being originated in combat.

Originally posted by Ant Harrington
I have to agree with RobAnt,I didn’t see anything resembling a Derry in the last moments of the Firefly’s flight. It seemed to me that the pilot was trying to pull the aircraft through a half loop, from which I would guess he intended to roll off level at the top and thus find himself heading back towards the airfield. The rolls and oscillations which the aircraft performed occurred after the stall and departure from controlled flight.I think any notion that the pilot was attempting a Derry manouvre ought to be knocked on the head.
I don’t really like to get involved in the speculation surrounding this acident,but I witnessed the accident first hand and I feel it’s important to get things right and prevent misinformation from spreading.

It didnt resemble a derry turn as he only completed the first half- i.e. he got to inverted and did not pull through the remaining 45 degrees.This is where control was lost – I saw no traits of a stall, indeed the aircraft appeared to be at good speed, but the pull out was initiated inverted. Tempest nut has said that a “dodgy” derry had been completed at the western end – this leads me to believe that a second one was to be attempted. I presume by half loop, you refer to a split S whereby the pilot will pull up to the near vertical ,roll inverted and pull out as if completeing a loop. If this was being attempted and I very much doubt it (never, ever seen the firefly fly vertical aerobatic manouveres- rolls and derrys , yes, but loops, cubans, split s -no) he was way too low and underpowered. The only person who can answer us isnt here any more.

At major displays there is usually a safety committee, they are there to monitor each display in turn and, if neccassary “red card” a display. This is as well as a Flying Display director being able to terminate displays.

Im told by friends down that way that at Biggin the committie was sited away from the tower, the missed manovoure was spotted by them and they attempted to contact the tower to get the display aborted. Their link with the tower was a walkie talkie, unfortunetly the other end in the tower either had a flat battery or was not heard. The last resort was to try to use a mobile phone but it was all to late. I am led to believe that a land line phone link was installed some weeks later.
Not sure why the safety committe didnt work at Duxford, some people believe, allegedly, the safety committe missed the failed manovoure and whilst several respected display pilots saw it the display was allowed to carry on. No doubt there will be comment made in the accident report which will remove all the speculation.

Another point, military display pilots, I believe, get their DA’s from the CO or an appointed senior officer, the private pilot has to get his from an experianced Display Pilot who is working to a very strict criteria. Different standards?

Comment made on the carrying of passengers during displaying flying, in the private sector it is in the main not allowed – however as the BBMF and RNHF are military they have there own operating rules. (One comment heard at a show last year was that you can’t tell the military anything as they believe they know it all). Obviously there is a certain required number of crew on complexmulti engined aircraft, the Sally B is an example but the CAA do rule out the ‘observer passengers’.

Another area of knowledge on how to fly these clasic aircraft are “the old boys”. Unfortunetly their knowledge tends to die with them. One old boy I met a few years ago made the comment on the jet formations that were becoming popular that on no account would he fly close behind a Vixen due to the wakevortex disturbance behind it, nearly did for him once. Shortly after we lost the Vampire at Biggin.

A comment on currency, lets face it, Warbird type of aircraft are VERY VERY expensive to fly with limited life engines, astronomic insurance, inspections etc etc. Every organisation has to look carefully at the balance of gaining pilot experiance, maintaining currency and keeping costs within a budget, it will be a well funded organisation that has pilots starting a season with 10hrs on type for that year. Should there be a rule that a pilot can only display that type of aircraft when he has a minimum of what? 10, 20, 30 or more hrs experiance? Imagine the effect that would have, someone would need to fund an awfull lot of flying time before the pilot could appear in a show. Does the 90 day rule apply to military pilots? Even so it is, I believe open to some abuse, it is possible for a pilot to do his 3 practise displays (say a total of some 30-40mins) the day before a show and then be quite legal to display in the show – is that really being current? It is a very difficult ball to juggle especially for the Military with budgets always being reduced and scrutinised. At the end of the day there is a wealth of knowledge in the private warbird flying industry, maybe the Military should tap into and use some of that flying experiance.

I believe if you look back over the last few years there are many accidents that were avoidable if ALL the elements to safety in display flying had worked. We in the UK are I think still way ahead of European countries and the US in safety but that doesnt stop us all hurting when anyone is killed.

Flying Control Committees are a feature of most shows, whether it’s just one person or a team. The P-63 accident at Biggin did highlight a problem with the system however. As many noticed, the P-63 did seem to have difficulty from an earlier loop prior to the final loop. The FCC had noticed this apparently, but were unable to contact the tower due to the phone being engaged or there was some other communcation issue.

As a result, a direct link between FCC and the control tower has been installed for all airshows since 2002.

The purpose of the FCC, (as the Shoreham FCC explained in that interview) is to monitor and report anything they see they feel uncomfortable with. They may not be able to stop the accident itself, but maybe able to alert ATC and the emercgency services which could save vital seconds in the outcome.

Yes I saw the program on wings. They were talking about the flying control comitee in the wake of the tragedies at Rouen and Biggin. It showed the FCC stopping a German Mig-29 at RIAT one year. They just got the tower to tall him to land because he had been low coming out of a moanouvre. This system only seems to work though if they can contact the tower immeadiately.

I remember seeing an interview on TV once about display pilot monitoring.

There was a programme shown on Discovery Wings last night (24th Apr ’04) covering accidents at airshows. Some of it was a bit too graphic for my tastes, but I stuck it out.

There is a monitoring group at (I think it was) Biggin Hill or Duxford. It wasn’t clear, at least not to me, whether this was a feature of all displays – but I got the impression it was.

The gentleman interviewed certain seemed very senior and experienced – yet enthusiastic about seeing the aircraft flown properly and in the right hands.

Originally posted by Papa Lima
I remember seeing an interview on TV once about display pilot monitoring. Someone being interviewed said that there were monitors among the crowd, not in the tower, and if they saw something about a display that they were not happy with, they could contact the tower immediately by cellphone or walkie-talkie presumably, and order the display to be terminated. If that is true, are these monitors present at all displays? It was something to do with being licensed to fly displays.

This sounds something like what Biggin Hill were doing maybe someone else has heard of this?.

I remember seeing an interview on TV once about display pilot monitoring. Someone being interviewed said that there were monitors among the crowd, not in the tower, and if they saw something about a display that they were not happy with, they could contact the tower immediately by cellphone or walkie-talkie presumably, and order the display to be terminated. If that is true, are these monitors present at all displays? It was something to do with being licensed to fly displays.

Originally posted by trumper
I seem to remember reading about the pilot of the P63 crash at Biggin Hill had also attempted his fateful manouvre before the crash that lost the plane and pilot, it was seen by the officials who tried to get his display stopped before the crash happened but could’nt get in touch with him.
I wonder if during the display routine a pilot is aware in the heat of the moment just how much height ,speed and energy they have lost during the previous manouvres and the dangerous situation they are in.
I wonder if there is a way of spacing the aerobatic manouvres so that as one is completed the pilot then has time to gain height and speeed and have a good look around before going straight into another one.

Sadly i was at Biggin when P63 crashed also,he had already lost control once in the flight and was flying a lot slower than you would have expected i was shocked when he went to attempt a loop,there are in my view similarities between the P63 and Firefly crash and maybe we should be looking at ways to stop a Routine when i pilot has been deemed to have done something unsafe i know Biggin implemented many safety ideas into it shows since 2001 and Duxford used a flare to warn Stephen Grey he had a undercarriage problem at the same show as the firefly accident .

Originally posted by TempestNut
I was watching from the eastern end of the airfield and I thought he was doing a Derry turn. As it was some 15 years since I had last seen the Firefly I was watching it like a Hawk, to the exclusion of the other aircraft flying at the time. When Bill turned at the western end of the field he did a Derry turn, but I was shocked at its execution and I said to some Dutch visitors that I had got chatting to “what’s he doing? he’s flying it like a jet” ( same thought as Firebird) He lost a lot of height during the turn and by the time he returned for the west to east pass. I said to myself “please please don’t do that again”.

This account may not be entirely correct but it is how it looked to me from my position. The question I would ask is why did he perform the second Derry turn when the first one had resulted in a large loss of height which he did not recover? Is there no mechanism for pilots realising something was not quite right and modifying the display accordingly.

I seem to remember reading about the pilot of the P63 crash at Biggin Hill had also attempted his fateful manouvre before the crash that lost the plane and pilot, it was seen by the officials who tried to get his display stopped before the crash happened but could’nt get in touch with him.
I wonder if during the display routine a pilot is aware in the heat of the moment just how much height ,speed and energy they have lost during the previous manouvres and the dangerous situation they are in.
I wonder if there is a way of spacing the aerobatic manouvres so that as one is completed the pilot then has time to gain height and speeed and have a good look around before going straight into another one.

So to return to my original question – a Derry Turn & a Derry Roll are the same thing – just spelt differently?

Wrenchbender, if you read my post through you should see that I actually agree with you.

Having not been aware of the Firefly’s sequence at the time of the crash and watching the footage, I assumed the next part in the sequence would be a right wingover at the top of the climb so as to position back towards the airfield.

However this wasn’t the case and TempustNut describes the fatal manoeuvre more or less as I saw it. One thing that did strike me was that there seemed to be some hesitation on the pilot’s part prior to initiating the roll at the apex of the climb.

A few months later, I saw longer footage of the Firefly’s sequence on the Biggin DVD and I was surprised at how much height was lost during the Derry Turns, compared to how I’ve seen the manoeuvre flown in the past. In all the instances I’ve seen, energy and height are maintained throughout the manoeuvre with no hint of the nose coming down as the roll is started.

And this is always what I understood the manoeuvre to be – a three quarter roll so as to reverse your direction for a turn the opposite way e.g. you three quarter roll left so you can now turn right to position yourself for whatever the next manoeuvre in your sequence is.

Btw, the latest edition of Pilot magazine has an A-Z of Aviation terms and this is how it describes the Derry Turn:

“A manoeuvre in which a tight (e.g. left) turn is reversed by rolling (left) and under, effectively reversing the direction of the initial turn.”

Maybe some of the display pilots that post here can clarify this.

Cheers

Paul

I was watching from the eastern end of the airfield and I thought he was doing a Derry turn. As it was some 15 years since I had last seen the Firefly I was watching it like a Hawk, to the exclusion of the other aircraft flying at the time. When Bill turned at the western end of the field he did a Derry turn, but I was shocked at its execution and I said to some Dutch visitors that I had got chatting to “what’s he doing? he’s flying it like a jet” ( same thought as Firebird) He lost a lot of height during the turn and by the time he returned for the west to east pass. I said to myself “please please don’t do that again”.

At the eastern end of the field he made a 45 degree turn to Starboard and flew off S/E over the area between Duxford village and the M11 Bill then rolled to starboard but was at least 30 degrees nose down ( if not more) when inverted and it appeared to me that as Bill continued to roll he found himself pointing at Duxford Village. He seemed to have at this point pulled back on the stick, reversing the roll? and I guess if you look at the TV footage without reference to the ground it looks as if he pulling over in a loop. The result of this was that from facing Duxford village he was now facing rising ground to the south with no hope of recovery. To me it appeared they hit the ground wings level and may have even bee nose up at impact. I did not see the news broadcasts at all, so this is from memory.

This account may not be entirely correct but it is how it looked to me from my position. The question I would ask is why did he perform the second Derry turn when the first one had resulted in a large loss of height which he did not recover? Is there no mechanism for pilots realising something was not quite right and modifying the display accordingly.

Originally posted by Paul Rix
I see where you are coming from Airgage. I guess that if you come from a non-aviation background (or have little knowledge about aviation) then “Pilot Error” can only be interpreted as straight forward incompetance. Those with an understanding of flying know there is a lot to flying an aircraft as complex as the Firefly and that “Pilot Error” can mean a lot of things.

Personally though, I consider “pilot error” is less damning than a driving charge of “undue care and attention” which is also used as a blanket label that is not always truely discriptive of what happened.

Incompetance is a little harsh. A one time goof could also be pilot error but only takes one to kill ya

Just goes to show the differences of opion dependant upon the position of view. From the the angle I saw it, 90 deg plan on from the field adjacent to the M11 it appeared to me a Derry turn was attempted….
I actually vividly remember saying to the other half, somewhat tongue-in-cheek,
“Ch***t…..he thinks he’s in a Sea Harrier…!”, by the time I’d finished that remark the aircraft had departed from flight……

I couldn’t say much at all after that point…….so very sad……

I was also at the show on that terrible day and my first thought was the pilot had attempted a stall turn but maybe it was just the aircraft falling off the top of the loop, but i did not see anything that looked like a Derry turn

Originally posted by Ant Harrington
I have to agree with RobAnt,I didn’t see anything resembling a Derry in the last moments of the Firefly’s flight. It seemed to me that the pilot was trying to pull the aircraft through a half loop, from which I would guess he intended to roll off level at the top and thus find himself heading back towards the airfield. The rolls and oscillations which the aircraft performed occurred after the stall and departure from controlled flight.I think any notion that the pilot was attempting a Derry manouvre ought to be knocked on the head.
I don’t really like to get involved in the speculation surrounding this acident,but I witnessed the accident first hand and I feel it’s important to get things right and prevent misinformation from spreading.

I also witnessed the accident first hand and have to agree totally with what you say i don’t intend to get involved in anymore speculation on this accident its morally wrong to do so in my view.