Originally Posted by
industry insider
John R81 wrote
Not always if the change is gradual. Before the days of HUMS, I visited a base where one crew flew the same aircraft everyday. They were both very professional and were fussy about the state of the aircraft. I performed a line check on one of the crew and thought that the aircraft was a bit rough compared with the last time I had flown it a month prior. A track and balance showed it was close to the limit and had deteriorated, but the crew which flew it every day hadn't noticed.
This is a common phenomenon with human performance - “The
boiling frog is a fable describing a
frog being slowly
boiled alive. The premise is that if a
frog is put suddenly into
boiling water, it will jump out, but if the
frog is put in tepid
water which is then brought to a
boil slowly, it will not perceive the danger and will be cooked to death.“