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Old 10th Jan 2015, 02:05
  #45 (permalink)  
Kharon
 
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What a tangle.

Interesting transcript though, just get settled into a pattern and the game changes. Had to read through it a couple of times and several passages more again. Everyone got a corner. But, from a risk mitigation perspective, the messages are clear enough.

That said, I find both the Beard and Soutter analysis of what happened (or may have happened) to be persuasive and refreshing, given the mix of previous statements. You can imagine it easily, tight behind a slower aircraft, slowing it all down to follow and then a distraction (engine, electrical or ancillary system) if the engine was misbehaving, the option to go-around could be taken out of play. It's a problem, but I'm not certain that 'S' turns while wrestling with the emergency gear at low speed was a solution; perhaps the 'manoeuvring' was no more than an effort to land to the side of the runway, in an effort to evade the Auster. Don't know. Then we don't know, not for certain that there was an actual issue with the gear or flaps or engine, it's just not clearly stated. Beard and Soutter allude to a strong possibility of mechanical problems, but do not commit to absolutely. Good effort from both though, given the constraints and lack of official assistance.....

"Mr de Vere noted in his statement that Dr Uscinski’s aircraft was following his Auster aircraft at a considerable distance apart and much lower. He did a mental calculation at the time that the extremely slow speed which his aircraft normally flies at, combined with the much faster speed that Dr Uscinski’s aircraft would need to remain airborne, would have resulted in the Dr Uscinski’s aircraft closing in significantly on his aircraft as it turned from base to final. He was of the opinion that Dr Uscinski was probably performing an ‘S’ shaped manoeuvre to give the Auster time to exit the runway, which is quite normal in the circumstances."
Can someone help with a question: I thought that any airframe power-plant combination would come with a clearly defined, published CG range and a method of determining whether the CG was within that range before flight and likely to stay within that range for the duration, at very least for certification purposes. I'm intrigued by the apparent lack of any related documentation.

There's much made of the alleged 'over-weight' specification but little data on where that weight would act, throughout the flight envelope. Given that the 'original' manufacturers weight specification was used for certification the fact that it was 'not within category' seems a little 'off', sure it was 'heavy' for the cat but was it heavier than the certification weight?

Sorry, don't mean to bang on, but this area of the transcript keeps troubling my curiosity bump. One of the reason I ask is there is mention of lead ballast and batteries being shuffled about, seemingly without any mathematical calculation being made as to the effect of shifting the CG in a series of educated guesses. Flying a 'little' out of the CG range is not too big a deal, but once the CG is located outside of sensible limits, things can and do go wrong.

"Mr Soutter said that in addition to the weight issue, was the balance issue. With reference to the Flight Manual, this aircraft would have had adverse handling characteristics with 8.1kg of tail ballast and a battery which had been moved aft of its original position. Dr Uscinski would have found it very difficult to control the aircraft in pitch and direction as a result, particularly at approach speeds. When it is taken into account he would have been deliberately flying slower as a result of the tasks at hand, then the weight and balance issues would have been a major contributing factor to the loss of control of the aircraft."
Anyway, it's hard to find a real quarrel with the 'Findings', but it's an interesting study of human frailties and the way the ever present, devious holes in that famous cheese can all line up.
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