The sales decline was most severe - about 40 per cent - in the business and regional jet market.

Regional jet traffic remained strong last month.

In its primary role it serves as a regional jet, short-haul airliner or regional airliner.

The aircraft was initially expected to be the first regional jet aircraft to adopt carbon fiber composite materials for its airframe on a significant scale.

Among some of these categories included among the short-haul civilian passenger jets are both longer and shorter ranged narrow-body jet and regional jet types.