[Josh F]

A VIRGIN Blue jet with 55 passengers on board was forced to make a high-speed landing at Melbourne airport in what air safety investigators are treating as a serious incident.

The scare follows a host of safety issues with Australian planes that began three weeks ago when an explosion on a Qantas 747 blew a hole in the fuselage.

The 78-seat Virgin Blue Embraer jet from Sydney was close to landing at 8.50pm on Sunday when the pilot experienced problems extending the plane's flaps and slats. Emergency services were immediately put on standby as the Brazilian-built jetliner approached the airport.

The flaps, at the rear of the wing, and the slats, on the front, deploy to increase the wing's surface area and slow the plane when landing.

A Virgin Blue spokesman said Sunday's problems involved a sensor controlling the slats.

He said the pilot followed set guidelines, with the flaps only partially extended and the slats not extended.

"As a matter of practice, the flight crew notified air traffic control that alternate procedures were being adopted for landing," the spokesman said.

"Then air traffic control, in turn, as a safety precaution put emergency services at the airport on standby. The aircraft landed without incident, and following a subsequent maintenance inspection, the sensor was reset and the flaps were checked for correct operation.

"The aircraft returned to service the following day. We of course notified the Australian Transport Safety Bureau, as per standard procedure." Landings with flaps and slats unextended must be made at higher speeds to prevent an aerodynamic stall.

Attempting to fly with either unevenly deployed would unbalance the aircraft and could cause it to roll, although modern aircraft have mechanisms that stop the panels deploying too far if a problem is sensed.

An ATSB spokesman said pilots trained for such incidents.

"A flapless approach is ... obviously not a routine activity that's done daily, but it's certainly a common thing that's practised in simulators," he said.

The Australian