Dr Annette Ruge of the UK Civil Aviation Authority’s Aviation Health Unit, a member of the international team that worked on the ultra-long-range (ULR) studies, observes that for passengers, such a flight is “only 4h more” than services that have been in operation on popular routes for some time, and she is generally sanguine about passenger welfare and behaviour, even on the longest flights.

For passengers, the main problem posed by ultra-long routes is boredom and its side-effects, says Ruge, as opposed to threats to their physical well-being like deep vein thrombosis (DVT). She says healthy people do not face risks specific to the aviation environment, even on ULR flights.

Airbus bears out Ruge’s assessment of the boredom issue, saying that in-service experience shows passengers clearly prefer non-stop journeys to flights with an en-route refuelling/crew-change break, but when they reach the point where there is still about 2h to go they become restless. Passengers say they prefer non-stop ultra-long services to journeys with a break because they avoid the stresses associated with connecting flights and additional security procedures.

Old people, passengers with known medical problems and mothers with babies should seek the advice of a doctor before travelling on ultra-long or long-haul flights, Ruge advises. Because prolonged physical immobility is what makes long-haul flights unique, she says, airlines should make passengers aware of the need to exercise and limit alcohol and caffeine intake.

Passengers should be shown a video illustrating isometric exercises they can carry out in their seats. These exercises are effective, Ruge says. Travellers, like the crews, should have rest times, when the cabin is dimmed and activities like playing computer games are banned. SIA says its ULR cabins are equipped to provide “mood lighting”, which simulates night, day and dusk.

The threat of bad passenger behaviour does not appear to increase with the length of the flight, says Ruge. This aspect has always needed skilled management by cabin crew, she says, and the additional time on board does not appear to introduce any new dimensions to the issue – although smokers will need plentiful supplies of palliatives such as nicotine patches.

Source: Flight International