MIAMI – The majority of long-haul flights are flown during the night. This is due to time zones and when people prefer to travel. Going to sleep after departure and waking up before arrival, is a good way to maximize your time. Also, many airports around the world have night curfews, like London Heathrow (LHR): 11 pm to 6 am.
As pilots, we need to plan our sleep, to be alert during these flights. Today I’m staying at a Heathrow hotel and planning to sleep this afternoon, before a late-night departure to Hong Kong. We’ll have three pilots on this flight and we each spend around three hours in the crew bunk during the night.
The remaining two pilots stay alert, by checking the aircraft systems, monitoring performance, communicating with en-route ATC and checking for changes of en-route weather.
Window of Circadian Low
Our circadian rhythm in alertness means we are most sleepy between 2 am and 6 am, with a peak in sleepiness around 4 am. During this time our alertness dips and it can be difficult to stay awake. This period is sometimes referred to as the “window of circadian low” (WOCL) Being aware of this, we can mitigate its effects, to get us through these dips.
We, therefore, fly with the cockpit lights bright, like any normal office. Although when flying in areas of forecast thunderstorms, or if our radar alerts us to weather, we dim the lights to better scan the horizon. Nothing beats a trained eye and years of airmanship.
On particularly dark (moonless) nights we sit our chins on the dash, to avoid the cockpit lighting as we stare into the blackness looking for storms. When we do this, we can also see the stars, satellites, and sometimes the Northern Lights or shooting stars.
We monitor each other’s alertness with conversation and regular visits from the cabin crew, coffee also helps me. But the best preparation for operating a Long Haul night flight is planning your sleep. Good Night.
Featured image: Chris Pohl