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Fight The Fatigue

Are passengers in danger of falling into the hands of a snoozing pilot? Captain Lim Khoy Hing explains the strict regulations that govern pilots’ rest patterns to ensure safe flying for all. 

     I have often been asked by concerned travellers how pilots rest sufficiently to fly long journeys. Some even wonder whether pilots are allowed to sleep on long haul flights (see Sleeping on the Job, July 2013) and others query whether sleep deprivation and jet lag would jeopardise a flight. Fear not! Flying is highly regulated in the airline industry as passenger safety is of paramount importance.

Pilot napping on the bench at an airport.


It is a well-known fact that the effect of prolonged sleep deprivation and jet lag leads to fatigue. Very simply, fatigue is a state of weariness that could lead to a decrease in a pilot’s ability to carry out his task efficiently. It is therefore understandable that passengers may be concerned as the lives of 300 or more passengers on board are in his hands.

     Despite rules being implemented within the aviation industry to address such issues, fatigue is an expected condition of modern life. So, what procedures are there in place to mitigate fatigue in a pilot’s flying schedule?


Among the strict regulations imposed on airline pilots are prohibitions on flying more than 1,000 hours a year or 100 hours in 28 days. Pilots may not be scheduled to fly for more than 30 hours in any seven consecutive days and must be given two days off for every seven days of flying. Since pilots fly at odd hours of the day, a day off is clearly defined – strictly a 34-hour period with two nights at home. 

     To prevent jet lag from affecting a pilot, flight duty time is also taken into account. This depends on if the pilot has acclimatised or not. To be acclimatised, a pilot must have rested sufficiently or three days if in a new destination that is more than two time zones away.

     If he has not acclimatised and begins work very early in the morning, he would be restricted to shorter working hours. As such, the airline industry is fully aware that good rest is very important. Such rules ensure pilots are not overworked and therefore do not jeopardise the safety of passengers in the air.     

     Despite the restrictions that limit how much a pilot can fly and dictate sufficient rest before flight, there have still been infringements by some pilots. On February 12, 2009, a Dash-8 plane belonging to Colgan Air (which has since ceased operations) in the US stalled and crashed whilst landing at Buffalo Niagara International Airport due to pilot error. The chairman of the safety board was of the view that fatigue was one of the factors that contributed to the crash. She felt that the crew did not obtain adequate rest before reporting for duty and that it was clearly a contributing factor.

Have sufficient rest before flight.

“…For a 13-hour flight to London from Kuala Lumpur… regulations state that the flight must be crewed by at least two captains and two first officers. They share their flying equally. Hence, each team would be flying for six and a half hours only and safety would not be compromised in any way.”


A FAA (Federal Aviation Administration) scientist testified in the inquiry on the Colgan Air crash that sleepy pilots are likely to make errors in judgement and have trouble concentrating and following multiple sources of information. In the Colgan Air crash, the crew lost track of their airspeed, and when a warning system was activated, the captain reacted wrongly, pulling the nose of the plane up instead of pushing it down, causing the plane to stall.

     On the ground, we’ve heard of people suddenly ‘waking up’ and realising they have been asleep for a few seconds. Imagine if it were to happen on a flight at a crucial moment!

     This actually happened on one of my flights when a trainee pilot fell asleep on a descent to land. Fortunately, the plane was still very high on the approach and on being awakened from his sudden slumber, he confessed that he did not realise that he had fallen asleep. He admitted that he was extremely tired on that particular day. It was not because of any long flying duties but rather his fatigue was being self-induced through improper rest prior to his flight.

     A NTSB (National Transportation Safety Board) safety study of accidents by major US carriers involving flight crew during the period of 1978 to 1990 expressed concern about fatigue. It stated that half the captains had been awake for more than 12 hours prior to their accidents. Half the first officers had been awake for more than 11 hours.

     On August 18, 1993 in Guantanamo Bay, Cuba a DC-8 collided with the terrain on landing when the captain lost control of the plane. Investigators found that the flight crew had experienced a disruption of circadian rhythms and sleep loss. They had been on duty for about 18 hours and had flown approximately nine hours.

     Another traveller once asked me how a pilot stays awake for a 13-hour flight to London from Kuala Lumpur. For such a longhaul flight, regulations state that the flight must be crewed by at least two captains and two first officers. They share their flying equally. Hence, each team would be flying for six and a half hours only and safety would not be compromised in any way.

Have sufficient rest before flight.


On May 5, 2012 at Munich airport, an Air Berlin B747 requested priority landing after its pilots declared a distress call stating that they ere extremely fatigued. The jumbo jet was carrying 335 holiday makers home from Spain and had to be landed on autopilot. The plane touched down safely after they were given priority. A distress call arises when the pilot makes a ‘Pan-Pan’ call three times indicating that they are in a state of urgency. When declared, they would be assured of an immediate landing even if they are behind in a queue. A pilot will only send such a message when he knows that he cannot guarantee the safety of the flight. It appeared that the crew had been on duty for 10 hours at the time of the incident and considered that their state of alertness to be at the very limits of what is necessary to ensure a safe landing. This was the first time that pilot fatigue had been blamed for such an incident.


Lest the thought of your pilot lacking the alertness to fly safely worries you, rest assured that safeguards are in place. Mandatory days off, rest days and acclimatisation, amongst others, are clearly defined. Jet lag problems are recognised and handled accordingly so that the majority of airline pilots who take off are well rested every time.

     Your captain and his crew are almost always bright eyed and bushy-tailed before their flight – regardless of the time. Safe flying always.

Captain Lim Khoy Hing is a Simulator Flight Instructor with AirAsia X.

     Captain Lim Khoy Hing is a former AirAsia Airbus A320 and AirAsia X A330/A340 pilot who also used to  fly the Boeing 777. He has logged a total of more than 25,500  flying hours and is now a Simulator Flight Instructor with AirAsia X. In his spare time, he shares his opinion on aviation issues with others. For more air travel and aviation stories, check out his website, ‘Just About Flying’ at  www.askcaptainlim.com.

Life in the Skies Captain Lim Khoy Hing.

     Like what you read? You can read more articles and stories in my book Life in the Skies. You can purchase copies on board or at the AirAsia Megastore kiosk at LCCT Kuala Lumpur, all major bookstores in Malaysia & Singapore or online at  www.airasiamegastore.com/life-in-the-skies.html.