HERC - XV198 – Crash COLERN 1973
FWIW, there was a Canadian C130 that crashed after losing both on the same side. Our UTP, CM, thought it would be good to get in the sim and see if it could be recovered. I went along for the ride and to select "gear up" as his arms weren't long enough to reach from the Captain's side. Tried it several times and crashed every one.
It seems that losing two on one side at low speed isn't bad enough but when sticking in a full boot of rudder into the good engines to correct the swing, not only does it act like a giant air brake and slow the aircraft but the action of yawing the aircraft in such a way seemed to stall the wing with the good engines and we just rolled over it and went more or less nose first into the dirt.
This was somewhere between 90-93 at LYE where I was one of the Training Co-ordinators.
May not have been a factor in the Colern crash but I thought it may be of interest.
Doc C
It seems that losing two on one side at low speed isn't bad enough but when sticking in a full boot of rudder into the good engines to correct the swing, not only does it act like a giant air brake and slow the aircraft but the action of yawing the aircraft in such a way seemed to stall the wing with the good engines and we just rolled over it and went more or less nose first into the dirt.
This was somewhere between 90-93 at LYE where I was one of the Training Co-ordinators.
May not have been a factor in the Colern crash but I thought it may be of interest.
Doc C
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I think we are getting into the territory of finstall if memory serves. Without the speed to ensure aileron authority the rudder causes a slip towards the dead wing.
When the side slip gets too bad, it masks the rudder, coupled with all the thrust and lift on one side, inevitably the roll is uncontrollable. VMCA2 is named because the aircraft is uncontrollable below that speed without chopping the thrust on the asymmetric outboard and changing the dynamics.
On a roller, we typically rotated below 110 kts, so chopping an engine (No 1) would induce a yaw and roll easily corrected by rudder and/or bank. No 1 feathered normally and presented minimum drag. No 2 then ran down and the prop would have NTSed, which does minimise drag without feathering the prop, but causes drag nevertheless.
So with only drag on the port wing and full blown thrust/lift on the starboard, there is not enough aileron authority to control the aircraft's roll. Finstall only exacerbates an already fraught situation.
This is all from memory, so please forgive me if it's a bit hazy, it was over 30 years ago we taught this accident, to help prevent further ones.
It's perhaps the enduring legacy of this accident that it never again occurred in the RAF.
Talking of the Canberra accidents above (along with Meteors), the irony is I lost two colleagues 10 years later on 231 OCU when a simulated asymmetric exercise went wrong at Wyton. The SOP was that tip tanks had to be empty or not fitted for this exercise (EFATO - simulated), however this aircraft had half tips (1000 lb or so) in the tips and the inertia was again, uncontrollable and the aircraft crashed after rolling to the right. It was the Stn Cdr who was transiting to Kinloss for a simulator attempting to get his ticks done for the Canberra en route.
Some lessons are SOo hard to learn.
When the side slip gets too bad, it masks the rudder, coupled with all the thrust and lift on one side, inevitably the roll is uncontrollable. VMCA2 is named because the aircraft is uncontrollable below that speed without chopping the thrust on the asymmetric outboard and changing the dynamics.
On a roller, we typically rotated below 110 kts, so chopping an engine (No 1) would induce a yaw and roll easily corrected by rudder and/or bank. No 1 feathered normally and presented minimum drag. No 2 then ran down and the prop would have NTSed, which does minimise drag without feathering the prop, but causes drag nevertheless.
So with only drag on the port wing and full blown thrust/lift on the starboard, there is not enough aileron authority to control the aircraft's roll. Finstall only exacerbates an already fraught situation.
This is all from memory, so please forgive me if it's a bit hazy, it was over 30 years ago we taught this accident, to help prevent further ones.
It's perhaps the enduring legacy of this accident that it never again occurred in the RAF.
Talking of the Canberra accidents above (along with Meteors), the irony is I lost two colleagues 10 years later on 231 OCU when a simulated asymmetric exercise went wrong at Wyton. The SOP was that tip tanks had to be empty or not fitted for this exercise (EFATO - simulated), however this aircraft had half tips (1000 lb or so) in the tips and the inertia was again, uncontrollable and the aircraft crashed after rolling to the right. It was the Stn Cdr who was transiting to Kinloss for a simulator attempting to get his ticks done for the Canberra en route.
Some lessons are SOo hard to learn.
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surviving Pax
I was chatting to a gentleman last evening in Cleethorpes, he had been an Army Aircraft dispatcher and was on board XV198 during that mission. They were given the option to stay on board for simulated training but elected to get off during a brief landing at Colerne. He was then saying that the aircraft then proceeded to crash killing all 5 on board.
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Perhaps the youngest witness to the crash.
One of my earliest memories is of this crash. I was very nearly 4 years old when the crash happened. I was playing outside at the end of Poplar Way. I can vividly remember seeing the Herc bank over hard and crash into the ground. I remember looking over the fence on that road to see the plane and seeing the fireball and the smoke. Being not quite 4 I don't remember much else. It has been rewarding to know that I didn't imagine it and it surprised me just how many memories came flooding back when reading others accounts.
Originally Posted by M2dude
While I was in the mob, circa '67 to '74 (almost exclusively at Lyneham) there were a total of 4 crashes. The first was in 1969 XV180 at Fairford, which occured in similar circumstances to 198, resulting in the tragic loss of the 5 crew. The A/C was on MCT and doing simulated engine failures. (Can't 100% remember what the cause was though).
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Daughters recollection
I was 16months when this happened but my siblings remember it vividly as they were in the school playground at the time. Our Dad was supposed to be on this as the Flight Sergeant but swapped places at the last minute. He always carried the guilt that he wasn't with them until he died in 2012.
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If the 'flying' characteristics of the K Sims were at all representative of the aeroplane the test may have had a tad of reality about it.
B 707 control logic (such as it was) allegedly.
B 707 control logic (such as it was) allegedly.
