Do pilots sleep in flight? – A look at controlled rest for flight crew
A look at the rules and regulations regarding pilots sleeping in flight.
Do pilots sleep in flight?
The simple answer is yes, sometimes on certain flights.
This is not something to be alarmed about. In pilot terms we call sleeping controlled rest. This procedure has been proven to improve safety and it is more common on longer range flights scheduled overnight.
Remember controlled rest is different to bunk rest. Controlled rest is taken in the operating seat and bunk rest is on flights with more than 2 pilots who rotate rest in a separate facility (bunks).
The principle is to allow a pilot to get up to 45 minutes of sleep at periods of low workload (in the cruise). This should improve their alertness levels during periods of high workload, for example the descent, approach and landing.
The principle of controlled rest is to allow the pilots to boost alertness and energy. It’s the equivalent of a “power nap”. Ideally controlled rest should be between around 10 – 20 minutes as this limits you to the lighter stages of non-rapid eye movement (NREM) sleep. Sleeps between 30 and 60 minutes can result in sleep inertia when you wake up, which will leave you feeling groggy similar to a hangover.
There are set rules that have to be followed, such as:
- Controlled rest should be discussed and agreed to by both pilots
- Controlled rest should be limited to a predefined period between around 10 – 30 minutes.
- Only one pilot should take controlled rest at a time and that should be in his/her seat but with the seat pulled back away from the controls.
- Once the resting pilot is woken he should avoid operating the controls for at least 15 minutes to ensure he/she has fully awoken and is alert. They should also be awake for at least 15 minutes before any high workload situations such as initiating the descent.
- The resting pilot should ensure the operating pilot is adequately briefed to enable he/she to carry out their duties during the single-pilot operation.
There is a risk that the non-resting operating pilot may fall asleep too, to mitigate this the cabin crew are informed control rest is taking place and regular contact is made between the operating pilot and the cabin crew.
Some aircraft also have a facility whereby a warning is sounded if none of the controls have been touched for a specific time period.
Let’s consider this example in terms of what is safer with resting / sleep onboard:
Two pilots are operating a night flight to Tenerife from Manchester. The report time for work is 20:00 on Monday evening, the flight is planned to leave Manchester at 21:00 with a block time (flight time and taxi time at both ends) of 04:30 giving a scheduled landing time of 01:30.
The turnaround time is 1 hour meaning the return flight departs at 02:30. Again it’s a block time of 04:30 back to Manchester giving a scheduled landing time of 07:00, the pilots would then be off duty at 07:30 and have to drive home. This is all if the flights are running on schedule.
Naturally the pilots would sleep normally overnight on Sunday (although may have operated that day too) into Monday and they would try to either lay in or go back to sleep in the early evening for a couple of hours before reporting for duty depending on how long their commute is. Effectively they are losing one nights sleep.
The question is would it be safer to allow each pilot a 30 minute nap on each sector to ensure they are more alert or to not allow this procedure at all?
Now you have the facts what do you think?