In article
,
Mike125 wrote:

I don't see how a mis-adjusted altimeter gets by the pre-flight
checklist. Instruments: altimeter set to field elevation?

You check it, see that it's a bit off, and set it so that it's correct.

All the while, never noticing that the thousands hand is in the wrong
place.

The human brain has a powerful capacity for illusion. If you "know" that
something is true, it can be difficult to see otherwise. Especially when
the object in question is small and you're not concentrating on it.

--
Mike Ash
Radio Free Earth
Broadcasting from our climate-controlled studios deep inside the Moon