Air Transport

^{By David Learmount in London}

Express package-carrier DHL is working with UK regulators in an effort to safely increase night flying by its pilots following encouraging results from a study involving low-cost carrier EasyJet.

The EasyJet-funded pilot performance and fatigue study demonstrates the feasibility of more precisely tailored flightcrew rostering systems, says UK Civil Aviation Authority flight standards officer Derek Brown. This contrasts with prescriptive systems that set the same limits for all operators, although those would be retained as the basic standard. UK-based DHL Air operations director Chris Hall confirms his airline wants to explore the same area.

The EasyJet study, overseen by the CAA’s Safety Regulation Group, started two years ago and has produced such useful performance data that Brown says he will now oversee a similar study on DHL’s night freight operations to see if the carrier can vary its roster to get more productivity from its pilots while reducing the risk of fatigue-related pilot mistakes.

Results from the EasyJet research enabled the CAA to grant a “permanent alleviation” for the airline to operate a pilot roster that would not normally be accepted under the authority’s flight-time limitations (FTL). The agreed variation allowed EasyJet to move from a six days on duty/three days off (6/3) roster to a five days on early duty/two days off/five days on late duty/four days off (5/2/5/4) routine, which produced a demonstrable reduction in pilot-reported events; operational exceedances measured by flight data monitoring (FDM), and non-critical mistakes. EasyJet’s director of safety and security Capt Peter Griffiths explains that the standard CAA FTL does not allow five consecutive days on early duty, so the duty days on the original 6/3 roster consisted of three early shifts followed by three late. Test results showed more mistakes were generated after the shift from earlies to lates, whereas under the 5/2/5/4 roster the event rates dropped and levelled out (see bar charts on P33).

The study of the 6/3 roster also produced unexpected results, including more exceedances immediately after the days off-duty than any other and, in days five and six, the fewest exceedances. The phenomenon may be explained by tired pilots relying more on automation, which provided smoother flying.

Brown and Griffiths are now following a new line of study to discover the effects of pilots’ off-duty lives on their performance.