Working with the top aircraft manufacturers and MROs is fascinating. The amazing thing is that while the fasteners we all use are very similar, the procedures and specifications vary widely – even within one manufacturer, and sometimes even between two variants of a component.
The fascinating ones are the military specifications – a fastener which is cocked in one direction is ok, while in another direction the same tolerance is a failure. We’ve heard many stories explaining why – it seems that a cocked or proud fastener can cause localised heating on a fast jet (ie supersonic) – and that this can cause a premature wing failure. Of course on a commercial airliner, that same fastener might cause drag if proud – but too deep, and it could weaken the panel…
The variation in the specification is something we’ve considered, which is why fastCHECK has a sophisticated set of algorithms to check all parameters – but then report the ones which matter on this aircraft.