BAE Systems and Vertex Aerospace announced Tuesday that they have signed a nine-year agreement to enhance availability of the U.S. Marine Corps' AV-8B Harrier II fleet.

The Harrier II is currently out of production. Through 1998, Boeing and earlier McDonnell Douglas as well as BAE built a total of 428 Harrier II V/STOL aircraft.

The Harrier II is a single- or two-seat, single-engine ground-attack aircraft now out of production. Through 1998, Boeing/McDonnell Douglas and BAE built 428 Harrier II V/STOL aircraft.