Sir Richard, point taken!
(We had three of these last year in one particular fleet in the span of two or three weeks before determining what the problem was. All three were immediate diversions and not a single eyebrow was directed toward the crew.)
Today 05:58
nnc0, can you give us more details about actions taken by the crews, did they descend, bring portable O's to the flight deck, try the system to verify the indication etc?
