Boeing is giving away little about a curious aspect of the new 787-9 observed as the aircraft departed on its maiden flight.

The aircraft’s main landing-gear doors opened as the aircraft rotated from runway 34L at Paine Field, and were clearly seen to be deployed as the aircraft climbed away.

This was despite the gear being left extended, as is normal for a first flight, following the take-off on 17 September.

Boeing says the landing-gear doors “functioned as designed”.

“That’s part of an enhancement we’ve made on the 787-9,” says the airframer, but adds that it is not discussing the reasoning behind the feature.

Boeing has secured orders for 388 of the -9 twinjets, the first of which is to be delivered to Air New Zealand in mid-2014.

787-9 first flight

Source: Air Transport Intelligence news