Work in Progress
It’s important to understand to what degree the Mk1 > Mk2 conversion was a work in progress. i.e. how mature was it and was it of acceptable quality.
MoD regulations acknowledge that every aircraft and equipment design is a work in progress, as there is a mandated requirement to Maintain the Build Standard, which must be reflected in the Safety Case.
It is a question of when a design is deemed safe enough to fly and, much later, enter Service operationally. This is a safety issue, although we all recognise that the political imperative often kicks in. In making this decision, the good book says “Professional engineering judgement is by far the most important part of Safety Management”. (The same paragraph states ““It has never happened before” is not valid evidence on its own, that a particular event will not happen”).
By 1994 MoD were 3 years into a policy of diluting this body of engineering experience (which came to a head in 1996 when CDP announced 600 job reductions at AbbeyWood as he didn’t see the need for engineering project managers). The practical effect was that, increasingly, MoD lost its capacity to apply professional engineering judgement, and the “advice” from e.g. Boscombe Down actually became the most significant authoritative input.
I’ve mentioned a few fundamental components of airworthiness there (judgement, experience, competence, resources, Build Standard, ensuring quality and maturity etc), and you may be able to cope if one of these defences in depth (to prevent accidents) is missing or compromised.
But, not only were ALL of them compromised, there were deliberate decisions made to save money by ditching some altogether. Thus, the Safety Management System had been compromised by the Political Imperative, breaching the basic rule. I think TR’s term “garbage” is a good description of the System which was meant to provide a safe aircraft.
The upshot is, I believe, the Mk2 entered Service prematurely. The design was immature, certainly in the area of FADEC software. There were various faults and (design) defects which, in isolation, may have been barely acceptable, but the cumulative effect should have been ringing bells. Not only that, the evidence shows a distinct lack of urgency to correct them.
In crude terms, it was a “simple” conversion programme but some new features in the Mk2 were crucial to flight safety and, in those circumstances, it is unwise to simply say “The Mk1 was ok, so that’s our safety baseline - just read across”. (And the tendency to over-rely on “read across” deserves a chapter of its own, being at the root of many an accident). In fact, only an idiot would not insist that the build standard was stabilised at induction to the conversion programme, giving you a KNOWN baseline, rather than an assumed one. Yes, it costs money, but given the mandated requirement to maintain that build standard was ditched 3 years previously, at the time it was a well known risk which project offices considered a routine task.
That a mandated, but missing, airworthiness component was considered routine is indeed an indictment of the System.