While one has to admit, that pilots are engaged in shift work patterns and such work patters produce greater disturbance in the wake/sleep cycles, one has also to take into account, that the work regulations of especially pilots take utmost care of these circumstances. Other shift workers, also doing safety related tasks, such as truck drivers, doctors and nurses in hospitals, airline maintenance staff, workers in atomic power generation plants normally work at least 1800 hours a year. Pilots work is limited by law to 900 flying hours per year. Working time additionally reduced if above average legs are flown or more long range flights (affecting the circadian rhytm) have to be made. Compared to other people more pilots engage in other professional activities in their leisure time. And it would be worth investigating how much stress and tiredness these are adding to their professional flying task.
I am really estonished that the University of Central England conducted the research on a website closed to pilots. If it is free to respond to a questionnaire, those people respond, who do so out of professional interest (pilots close to their union organisation), who expect further incentives (even higher wages or leisure time). The majority of pilots I got to know, showed less signs of tiredness than people working in offices or truck/bus drivers or people working in factories. A pilot once told me: I have to thank god every day that he gave me a job, in which I earn so much money and which gives me so much time that I am able to so many things which are even more interesting than flying an airplane.

Robert is painting a very misleading and totally factually incorrect picture here.

Firstly to quote that other safety critical workers work on average 1800 hours against a pilots 900 hour legal maximum. A pilots 'flying' hours, or more understandably the hours from being pushed back from the gate at the start of the flight, to shutting the engines down at the end of the flight are indeed legally limited to 900 hours.

That 900 hours is only a constituent part of a pilots working hours.

The flight planning, the checking of the flights paperwork, the transport out to the aircraft, the briefing of the cabin crew, the aircraft external inspection, the cockpit setup, the management of the departure, the list goes on....

900 'flying' hours is in reality 50% of a Short haul pilots working hours and 70% of a longhaul pilots hours. And I still haven't taken into account the time 'at work' whilst away from home. Last year I was away from home for 2,500 hours.

The second factually incorrect statement is that the longer the flight you operate, the less flying per annum you achieve due to the regualtions. Many of my colleagues fly long haul routes are often having to be taken off rostered flights because they will exceed the 900 flying hours per annum cap.

Unless you have personally experienced living year upon year, flying 5 sometimes 6 long haul flights, across multiple timezone changes and multiple night out of bed per month, you will not be able to empathise with the true meaning of permanent jet lag that affects your whole life.

Too tired to fly, you bet, but I wouldnt have a joob if I refused to fly whenever Im tired.

I think Robert is a little out of touch with the reality of being employed as an airline in today's climate.