CPLS
I don’t agree with Walter’s theory of a conspiracy to bring down the aircraft.
But that CPLS seems to have been fitted raises a number of questions, among them;
Given the Service Deviation for CPLS wasn’t issued until the following year, how was it fitted to ZD576 and under what authority?
An STF requires a Trials Instruction or similar. If it exists, what does it say? Given the nature of the kit, one could not trial it properly without someone on ground at the other end (which is where I encroach on Walter’s theory but I don’t think that particular flight would be tasked with such a trial, but stranger things have happened. After all, ZD576 was flying that day without any legitimate clearance to do so).
Was this the classified kit mentioned by a BoI witness? Either way, why is its existence not mentioned in the RTS?
Were the crew aware of the EMC problems notified formally in the later SD? We know the US fitted the kit – did the UK simply read across not understanding the possible effect on UK differences, like FADEC?
Given the nature of the kit, did it have to be integrated in any way with existing aircraft kit (which, by definition, was not cleared for use anyway). As nothing else was cleared, it is highly unlikely Boscombe would have ignored that to jump forward to testing and trialling with CPLS fitted. These things are done in strict sequence and on 2/6/94 Boscombe had yet to commence Nav and Comms work in earnest on a Mk2.
And why did the BoI not ask these questions?
Summary – If CPLS caused a problem the likelihood is it was EMC related or connected to the physical installation. But that is just an opinion. It was up to the BoI to check and they failed.