[LINK] Expert advise sought please...

[David Lochrin]

On Saturday 19 January 2008 10:58, Roger Clarke wrote:

> One of the important uses of parts-identifiers is and will be to
> enable investigations into accidents (e.g. a 777 crash-landing at
> LHR).
> [...]
> If the component is missing, so is the data contained in a chip
> that's integrated into the component.
>
> So it will be essential (and, to my understanding, is already a legal
> requirement) that the operator maintain and have accessible by
> investigators the full maintenance record of all controlled
> components on the aircraft.
>
> So, if there's a full record outside the aircraft, what are the
> benefits of a full record integral to the aircraft itself?

   These are good points.  I believe parts tracking is required for sub- sub-assemblies down to things like engine fans.  These get very hot, and I can't imagine any design of RFID tag which would survive that environment.  The Boeing project was probably a warehouse system.

   But there's a more fundamental consideration of good systems design.  Almost all aircraft accidents result from more that one failure (mechanical, procedural, etc).  In similar fashion, it's just too easy for a database to accumulate errors - for example, the database says that aircraft 'a' includes engine 'b' which includes fan 'c' when it's actually fan 'z' - and in an accident investigation one would like to be able to confirm by direct inspection of an engraved serial number which fan was involved.  It may well be that some mistake like that contributed to the accident.

   Disclaimer: my experience in the airline industry is now rather old!!

David