The most common way of boarding passenger planes is among the least efficient, tests have shown.

The best method has been the subject of study for years but now various approaches have been put to the test.

Boarding those in window seats first followed by middle and aisle seats results in a 40% gain in efficiency.

However, an approach called the Steffen method, alternating rows in the window-middle-aisle strategy, nearly doubles boarding speed.

The approach is named after Jason Steffen, an astrophysicist at Fermi National Laboratory in Illinois, US. Dr Steffen first considered the thorny problem of plane boarding in 2008, when he found himself in a long boarding queue.

He carried out a number of computer simulations to determine a better method than the typical "rear of the plane forwards" approach,publishing the results in the Journal of Air Transport Management.