If airlines could double the number of fully-flat sleeper seats in their business-class cabins without surrendering comfort, would they do it? US engineering firm MmillenniumM Group thinks they will.

The company's 'Air Sleeper' stacked sleeper seat design - originally envisioned for economy- and premium-economy cabins - has evolved into a whole family of architectures, including a 28in (71cm) wide model for business class. A prototype will be on display for the first time this week at the Aircraft Interiors Expo (A19B5).

"We're now more focused on the business-class cabin. The advantage to airlines is that they are able to achieve a far greater density than current business-class configurations," says MmillenniumM Group chief executive A I "Indi" Rajasingham.

"For example a 777 business cabin that we reconfigured for [one model of] Air Sleeper increased the number of seat beds from 53 to 110. This is at the limit we believe is allowed for that cabin because of emergency considerations."

Air Sleepers in economy, meanwhile, will not achieve greater density for airlines but passengers are assured of greater comfort, says Rajasingham.

MmillenniumM Group is in discussions with several airlines and has responded to requests for layouts.

The firm is confident that the Air Sleeper will meet airframers' stringent engineering requirements, and views the Boeing 777, Boeing 747 and Airbus A380 as "excellent candidates" for the solution. "The Air Sleeper is designed to use conventional seat tracks and therefore no modifications are required for the airframe," says Rajasingham.

He insists that the Air Sleeper will be able to withstand the extreme forces of 16gs that are required for certification, and meet the 90sec requirement for evacuation in an emergency. Upper tier passengers are naturally interleaved between lower level passengers during emergency egress, giving them a guaranteed footprint on the aisle, he notes.

MmillenniumM Group believes the Air Sleeper will prove particularly attractive to carriers that want to more efficiently use space on older aircraft. "There is an enormous opportunity for retrofits," says Rajasingham.

Source: Air Transport Intelligence news