Flight time limitation rules are the most contentious regulations aviation legislators have to draw up. Airlines want the rostering flexibility that permitted long hours confer, even if they do not plan to use the maximum except when plans go awry, and pilots want the protection of a cautious approach.
Right now the European Aviation Safety Agency is angering the pilot community by proposing an extention to permitted hours while the US FAA is reducing its own. BALPA is lobbying with colourful illustrations of the close correlation between human cognitive and physical performance when drunk and when fatigued. They say that pilots flying to the proposed EASA extremes will see them landing aeroplanes as if they had drunk "five cans of lager".
The draft EASA FTL rules will be published in December, with a further two months for comment.
Perhaps the most universally imitated FTL rule is the UK's long-running CAP371. But when it was released decades ago the Civil Aviation Authority issued a warning that should be echoing through EASA's halls as it struggles with proposed new FTLs. The CAA argued that FTL rules are effective only if operators respect the spirit of the law as well as the letter. In other words, any FTLs, except those so cautious that they virtually ground the airlines, can be abused. FTLs will always be a compromise between safety and practicality, and one-size-fits-all rules about flight time, irrespective of the varied types of operation individual airlines carry out, are inevitably imperfect. They can only ever be a safety net, and since that's what they are, caution must be the hallmark.
The fact that on both sides of the Atlantic the respective safety agencies are agonising over different FTLs carries an element of farce. Americans do not get fatigued quicker than Europeans or vice versa.
According to the International Civil Aviation Organization (ICAO), compulsory fatigue risk management is the future because it is not one-size-fits-all, and it puts legal responsibility for managing fatigue squarely on the airlines' shoulders - albeit under the stern gaze of the aviation authorities. Well-designed FRM is a win-win: it makes an airline safer and almost always improves its efficiency. So ICAO is right.