Farting, cutting the cheese, letting her rip, breaking wind - whatever you call it, experts say it's better out than in even on a plane.

Pilots, especially, have been urged to let flatulence out for safety's sake, but passengers risk being ignored by cabin crews if they do.

A team of Danish and British gastroenterologists produced a paper on flatulence on planes after one of them, Jacob Rosenberg, was inspired on a flight between Copenhagen and Tokyo.

The problem is that farting is an invariable consequence of digestion and people do it about 10 times a day.

But people may fart more on flights because of changes in the volume of intestinal gasses as cabin pressure alters.

Hans Christian Pommergaard, Jakob Burcharth, Anders Fischer, William Thomas and Professor Rosenberg have told the New Zealand Medical Journal the holding back option may seem "alluring" but there are drawbacks.

Stress, discomfort, pain, bloating, dyspepsia and other symptoms could ensue, while not discounting the chance that all the effort may be sabotaged by turbulence in any case.

"There is actually only one reasonable solution ... just let it go," the medicos say.

However, the odour - and women's farts smell worse than men's - may impair cabin service and thus the quality of life aboard the aircraft.

They warn of consequences in the cockpit.

"If the pilot restrains a fart, all the drawbacks previously mentioned, including diminished concentration, may affect his abilities to control the airplane," the researchers say.

"If he lets go of the fart his co-pilot may be affected by its odour, which again reduces safety on board the flight."

The specialists did not recommend setting farts alight, either on land or in a plane, despite its proven ability to reduce odour.

They reluctantly dismissed the notion of rubber pants with an attached air container for collecting gas as "somewhat extreme".

But they reckon putting active charcoal in passenger seats is a winner of an idea that could be backed up with special undies.

"The future frequent flyer may develop the ability to `sneak a fart' by wearing charcoal-lined underwear thus experiencing a comfortable flight in harmony with fellow passengers," they conclude.

Pre-flight passenger methane breath tests and reducing fibre in airline food options were also considered.