ramana wrote:One follow-up question.The unaltered flight computer was considered a cause for the upgraded Mirage 2K crash during takeoff. Has Dassault or IAF looked further?
I suspect it could be tin whiskers in the package over the many years.
The takeoff could have jolted the tin whisker and shorted a crucial circuit causing the crash.
Rather unlikely saar.
over the years, many modifications would have been made to the boards and newer modified boards would have been in place. A great many of these boards are wave soldered and microscopically inspected by certified techs, cleared by experienced inspectors, then boards are fired up to check that they are OK. Also, they have to pass LRU checks, followed by integrated system checks and again a majority are conformally coated and guessing for the mirage that all of them would be thus coated.
And then again, on installation aircraft system checks. Prior to this, on issue from stores, they all have to undergo a PIC, a pre installation check, certified as usable and passed by an inspector who has actual aircraft maintenance experience.
Tin whiskers are not much seen these days in aerospace practice.