MSBBarratt
Who cares if fixing the displays into the instrument panel makes the problem go away? What cannot be determined or measured is the degree of immunity gained by doing so.
Actually, you should care. Of course tests can be set up in a realistic cockpit installation. Indeed, I would say that there
must be system level tests. It may be that there is some level of anomalous propagation rather than shielding when the equipment is bolted into the actual flight deck. If those system level tests show a huge reduction in interfering signal strength then insisting on more internal shielding may be a nugatory exercise.
The question is: "at what point do you stop?" If you go inside the instrument panel shielding you get interference. True; and if you go inside the shielding on the equipment you can get interference too. So perhaps there should be another set of shielding just in case the first is damaged with one of the small scratches you quote?
At some stage one has to step into the real world and look at the entire airframe and test that. Then look at the vanishingly small chances of:
(1)Display blanking for a few seconds (no cases at all in operational service in millions of hours)
(2)at
precisely the wrong moment (must happen at critical phase of flight and
(3)
Simultaneously to BOTH PF and PNF displays) and
(4)
Simultaneously with a standby systems failure (ever seen standby instruments fail?)
(5) IMC
(6) with a pilot who cannot cope (vanishingly small chance
)
-- and accept that the probability of all these holes in the cheese lining up is too small to be concerned about as there are so many other hazards that are routinely accepted that have a far far higher probability of happening.
Should we ground all aircraft with any engine cowling fasteners and demand all aircraft engine cowlings be redesigned?
Should we stop operating if there are _any_ birds within the airport boundary or flying within the area of the SIDS/STARS
etc etc etc
Note that the above examples all
actually cause accidents incidents