Australian airlines ban knee defender gadget

The device's web site crashed this week due to high levels of traffic

The gizmo was devised by non-practicing American lawyer whose 1.7-metre height leaves him without much leg room on a plane. As a result, he created U-shaped plastic clip, which fits over the arms of a seat-back tray and prevents the seat in front from reclining.

The device was invented just over 10 years, but has seen its popularity soar as its usage becomes more widespread - and no less controversial.

The Knee Defender was used earlier this week on a flight from Newark to Denver, which reportedly led to a woman, frustrated at not being able to recline, threw water at the man behind her. Their fight caused the United Airlines flight to make an emergency landing.

Since then, the Knee Defender's website has crashed due to overwhelming traffic, while inventor Ira Goldman says that sales have climbed "substantially," reports the Sydney Morning Herald.

As a result, Australian airlines Qantas, Virgin and Jetstar have banned the device, reports The Daily Mail, on the grounds that it breaches safety regulations.

"Qantas would not permit attachments such as the Knee Defender to aircraft seats, and in any event such attachments would need to undergo stringent reviews to ensure they comply with Australian safety regulations in the first instance before being considered," a spokesperson told the newspaper.