Dalek & John Blakeley
Excellent posts.
Dalek, you said;
In our earlier jousts, you questioned my helicopter experience. You also said that the faults described by Sqn Ldr Burke were so isolated that they could not possibly have happened at the Mull accident.
Sqn Ldr Burke offered the following evidence;
“UFCMs were relatively common at the time of the accident and were occurring for years afterwards, and if caused by the Automatic Flight Control System (AFCS) leave no trace and are completely random in nature. From the first, a UFCM has been a primary possible cause of this accident and if it occurred in roll or yaw could well explain some of the still unexplained aspects of the crash. (It) would leave no clues in the wreckage”. (RB - 14th September 2002).
On 28th February 1994, 3 months before the accident, the RAF issued Special Flying Instruction (SFI) – SFI (RAF) Chinook 12. This warned;
“SFI(RAF) 12, Issue 1 (Restrictive) – Chinook HC Mk2. Undemanded Flight Control Movement.
There have been a number of incidents of yaw kicks on Chinook HC Mk2 ZA718 during recent flight trials at Boscombe Down. The characteristic is manifested by very sharp uncommanded inputs to the yaw axis which result in a rapid 3-4 degree change in aircraft heading, in both the hover and when in forward flight when the aircraft is subject to high levels of vibration.
Any aircraft exhibiting these characteristics is to be treated as having an Undemanded Flight Control Movement (UFCM). The heading hold is to be disengaged and the aircraft is to be landed as soon as practicable.
Engineering modification action is in hand to cure the cause of the problem and this SFI will be cancelled once the modifications (have) been carried out.
Action addressees acknowledge receipt of this SFI to RAF Handling Squadron”
Sqn Ldr Burke has kindly given me permission to quote him, thus;
“No. I did not know of this SFI. I suspect that very few people, either aircrew or groundcrew did. When another pilot (by coincidence Witness A) had this problem quite severely in Northern Ireland and I was called over there to fly the aircraft sometime after the Mull accident, we were not aware (of the SFI). Often SFIs took a long time to reach the actual front line operators, getting bogged down in the various layers of admin & command”.
I find this utterly compelling. Sqn Ldr Burke has been both ridiculed by MoD and prevented from giving crucial evidence, yet it transpires MoD knew he was right all along.
You will note “Engineering action is in hand” and “modifications” (plural). As everyone probably knows, such modifications don’t happen overnight. There must have been UFCMs, reports, contracts placed to investigate, engineering solutions agreed and modifications schemed to result in such a firm statement. This also begs the question why no immediate notification took place when the UFCMs first commenced.
Finally, try as I may I cannot find any reference to this SFI in any BoI or other inquiry papers.
I sincerely hope the new Review takes a look at this evidence.