The “spreadsheet” referred to will have been initiated to track the plethora of questions from various sources over the years; and, more to the point, ensure consistent answers were given. (Because the “Mull team” in MoD could not possibly retain the same staff for 14 years). To this end, they failed.
This is partly because the referenced documents, that is, a large part of the airworthiness audit trail, do not exist or cannot be found. These gaps in the spreadsheet are crucial, because they equate to gross failures or breakdown of process. Wherever you look, Hercules, Nimrod and others, this is the common denominator – failure to maintain airworthiness, including an audit trail. In the case of Mk2, an obvious example was the Boscombe decision to discontinue flying accompanied by their expert advice to MoD(PE) as to why they made this decision. To close the loop (audit trail) it was incumbent upon MoD(PE) and their Customer (the RAF) to be equally clear, in writing, why they chose to disregard this advice. I predict a large gap in the spreadsheet around this time.
This does not mean people have deliberately withheld evidence, although of course that is common practice. It is more an indication of the management ethos; call it the arrogance of power if you will, whereby senior staffs of the day (throughout the 90s) felt confident enough to issue edicts that airworthiness shall NOT be maintained. I well remember the Director responsible for a large part of this process gathering his troops together in the St Giles cinema and telling us (those holding delegation and responsible for maintaining airworthiness) that we were “the rump end of PE” and no longer needed. That would be about early-1992. Think of that timescale in the context of ZD576 and Mk2 in general, and you’ll see what I’m getting at. Quite frankly, the system was falling apart at the seams.
It would be an easy task to simply burn a CDR of the spreadsheet, even if the referenced documents have not been scanned and held electronically. The cost would be in redacting classified material, which one assumes is already done. No, I suspect the reason why Brian has been denied the information is because of what it doesn’t contain.