Whilst not a 125 (Westwind) not at Luton (Sydney, Kingsford-Smith) and well below 12,000' the only executive jet, ADI related accident I can recall was the Pel-air crash.
Most unlikely to be the one you are trying to recall, the accident report (discussed in past years on PPRUNE) makes for very sobering reading.
It was most likely caused by a reckless and ridiculous act, that began to align the "Swiss cheese slices" leading to tragic and needless loss of life.
The Westwind, which originated if I'm not mistaken from a Ted Smith design was, like the 125, one tough old bird. Not tough enough though for the sort of abuse it got in this case.
If today's pilots read this report they will no doubt give thanks that a) such practices are long gone and b) extensive use is made of very impressive simulators.
Best wishes to all,
BSD.