Most pilots will still work having taken a pill to get rid of a headache. But taking medication to sleep before a night duty? Where do you stop?
Putting the words "pilots" and "drugs" in the same sentence makes anyone sit up suddenly, even if they were dozing at the time. But if the speaker were to explain that he/she was referring to drugs that help a pilot working a night roster to sleep during the daytime, the listener would probably doze off again.
Many drugs are considered benign - they are seen as preparations that allow people to get on with their lives and their jobs. Some of them are only obtainable with a doctor's prescription, others at a supermarket - like headache relievers. Any of them could adversely affect a pilot's performance, yet many pilots will fly having taken them.
Pilots will take drugs to suppress the symptoms of the common cold, or they might be on a course of antibiotics to heal a small wound, and most will still fly - unless the malady feels debilitating in its own right.
A few long-haul pilots try to beat the effects on their sleep patterns of crossing multiple time zones by taking drugs to help them sleep. Those who do tend to swear by their effectiveness and claim they have no side effects.
A just-published UK Air Accident Investigation Branch (AAIB) report of a fatal crash gives - as the last of the three causal factors - "possible impairment of crew performance by the combined effects of a non-prescription drug, jet-lag and fatigue".
The January 2002 accident involved a Bombardier Challenger 604 that stalled at take-off just after unstick. One wing dropped dramatically and hit the ground and the aircraft was destroyed. All five on board died.
The stall was caused by frost on the wing of the aircraft, which had been parked on the ramp overnight. The AAIB says the primary cause was: "The crew did not ensure that [the] wings were clear of frost prior to take-off". It also says: "Traces of a non-prescription drug containing diphenhydramine, typically used to aid sleep, were found in both pilots...Specialist medical opinion was that it was possible that the judgement and reasoning of both crew members had been adversely affected by a combination of jet-lag, tiredness and the effects of diphenhydramine." This drug is available over the counter in the USA and the investigators found that "typically, there were no warnings about drowsiness or avoiding operating machinery on the packaging of sleep aid drugs sold in the USA containing diphenhydramine".
The captain of a Bombardier CRJ that had been parked overnight next to the Challenger had his aircraft de-iced. A dispatcher mentioned the icing to a member of the Challenger's crew, who was travelling as an observer, but no de-icing was requested.
It would be reasonable to assume that both pilots knew the Challenger has a wing with no leading-edge devices, which is sensitive even to slight icing. When the Challenger pilots arrived separately at the aircraft, each did a walk-around check.
In the cockpit the captain questioned the co-pilot, who was the handling pilot, on whether he had noticed and checked the wing icing. He received a monosyllabic reply suggesting the affirmative and then dropped the subject. Both pilots' passive attitudes are notable.
The day before, the crew had operated a long, three-sector day leaving their homes at 03:00 local time for duty starting in Atlanta, Georgia and ultimately crossing the Atlantic.
The co-pilot, whose sleep patterns the night before departure from Atlanta and overnight at Birmingham in the UK could be determined, had slept little both nights but the duty/off-duty periods were within legal guidelines.
It is universally agreed among transport pilots that getting quality sleep on airline rosters is frequently difficult or impossible, even when airlines respect duty/rest time guidelines. They also recognise that if they refused to fly every time they could not sleep properly the airline industry would grind to a halt - so they often fly when they are tired. But the vast majority of pilots are reluctant to take drugs to help sleep. They are right to be.
A UK Civil Aviation Authority circular for aircrew entitled "Medication, alcohol and flying" gives practical guidance, including warnings not to take medication unless it is essential; to test an unfamiliar medicine for its personal effects before deciding to fly, and informing doctors who prescribe any medication what their job is.
In the end, tiredness will happen and the best defence is common sense, self-awareness and thoughtful lifestyle planning. Finally, any pilot who is tired but decides to fly must admit it clearly to the other crewmember and organise a napping roster in the cruise if possible.
Source: Flight International
