Dan:
If there was a reliable and cheap scientific test for fatigue, in the same way as they can test blood alcohol level, you can bet there would be legislation to cover it.
Well, there
is a reliable and effective way to
anticipate fatigue, and that is to have some common sense when planning crews and establishing realistic regulations. But of course that would be too much to ask...
No, the writing (by flight crew) is on the wall, but the authorities, the airlines and the public prefer to wait till the inevitable happens.
The airlines have covered themselves legally with al kinds of vague memo's and 'fatigue awareness training' and for the authorities....well, they will probably react in the same way as in the present credit crunch: firmly asleep at the 'protecting the public' switch and blaming greedy managers for anything that goes wrong.