[Glider]

Originally Posted by 6S.Manu

The interview start with:
"Out of a total of 121 serious or major accidents to Spifires reported to us between the begining of 1941 and the end of the war, 68 involved structural failure in the air. Initially the most common reason for such failures, with 22 instances in 1941 and 1942, was aileron instability. The symptoms were not at all clear cut: the aircraft were usually diving at high speed when they simply fell to pieces."

If you read the whole piece the next few lines gives the details:-

Only after one of the pilots had survived this traumatic experience and parachuted successfully were we able to find the cause. During his dive he saw both of his ailerons suddenly flip up, producing an extremely violent pitch- up which caused the wing to fail and the aircraft to break up. In collaboration with RAE we did a lot of tests and found that aileron up- float was made possible by stretch in the control cables; in those days tensioning was a hit or miss affair with no compensation for temperature. On our recommendation the RAF introduced a tensometer which ensured accurate tensioning of the controls; this, and the simultaneous introduction of metal surfaced ailerons ('42/'43), cured almost all the cases of aileron instability in the Spitfire

And finishes with:
"a total of more than 22,000 were built, and we were called in on only 130 occasions"

Maybe I'm reading wrong, you know, but it does not state they were all the Spitfire's accidents during all the war... they are the ones reported to the Air Accident Investigation Branch.

You are reading that bit right but you also miss the bit where it says:-

Mr Newton was called in to investigate Spitfire crashes which could not be immediately attributed to pilot error (the same crashes which are detailed in Morgan and Shacklady).

Morgan and Shacklady is a very detailed book that details the history of the Spitfire including an entry for every SPitfire built. The number that the writer gives and the number in the Morgan and Shacklady book give for this type of incident match.

So we have two sources with the same number. Plus the Air Investigation branch are there for a reason. If you are in command of a unit of any type of aircraft and your planes start coming apart you will want to know why, so it isn't unreasonable to to expect losses of this type to be reported.

If you have better sources of information then put them forward, but until that moment I suggest this figure is as good as you are going to get.

I did have a breakdown as to when these incidents happened but cannot find it right now so cannot prove this next statement but the number that happened in training units was around 60-65% but I do put a caviet on that number but it wouldn't be unexpected.

Does this imply these were all the accidents regarding this kind of plane?
Could be that sometimes an investigation was not necessary?

I can only say yes to the best of my knowledge for the reasons stated. As for the second part I cannot say but its unlikely unless someone has repeated a mistake and they know the reason and the numbers do match