VH-FTA Spinning accident
I was unfortunately rather closely involved in the loss VH-FTA in 1968.
At the time I was doing my Instructor Rating with Bud "Spike" Jennings an ex WWII fighter pilot. Late the previous day we took FTA out for a session of aerobatics and spinning doing up to eight rotations in both directions recovering with no trouble at all.
The next morning Arthur Kell took out a student pilot for a PPL test usually involving one simple two turn spin and recovery, but as is well known, the aircraft did not recover and spun into the ground. Arthur was an ex RAF bomber pilot whose main claim to fame was that he took over Mickey Martin's Lancaster, Guy Gibson's second in command, when he finished his tour in the Dam Buster squadron after the famous raid and he subsequently flew RAF Brittanias.
For a time the three remaining Chipmunks (RSK, RCP & RSQ) were grounded then all fitted with the anti-spin strakes. Spike and I then had the dubious honour of taking RSQ, I think, for a series of spinning tests; this time with parachutes and again trouble free results.
Who knows if the twenty cent coin came from our pockets! The investigation showed that the forward movement of the elevators had been impaired by the coin but every time pressure was released and reapplied it popped out; Arthur would have been trying everything. Quite simply put the Chipmunk does a bad flat spin very occasionally; this is mainly due to D.H. Mosquito design of the tailplane where the forward set rudder is blanketed in spin. This is shown by the fact that nothing happens until the last inch or so of forward movement of the control column when it starts to bite. The strakes definitely helped by giving a more nose down attitude in the spin and if anybody had subsequently removed these on RSK they were crazy! More recent photos of RSK show them in place.
Beware Chipmunks do sometimes bite.