The Australian government will buy 18 RQ-7B Shadow 200 unmanned aerial vehicles and support systems at a cost of $175 million.

The UAV deal is part of a larger $1.1 billion plan to improve protection for Australia's troops, or diggers, in Afghanistan.

The 11-foot-long vehicle, with a wingspan of 14 feet, is powered by a Wankel 38 hp engine with an 8-hour endurance and a range of around 65 miles. Maximum speed is around 135 mph. It is launched from a trailer-mounted pneumatic catapult system and is retrieved upon return to base using an arrester wire.

The unarmed vehicle's suite of sensors includes high-resolution video and still cameras, ultra-violet sensors and laser direction finders. When used for battlefield surveillance, reconnaissance and target acquisition, it can feed back live footage to troops to help them decide tactics.

The deal includes two support systems, ground vehicles, training packages and maintenance support.

Australian Defense Minister John Faulkner said the Shadow 200 system would provide the army with a proven tactically mobile UAV system. He also said that the two Scan Eagle UAVs, operated under license from the manufacturers Insitu and Boeing, will remain in service until the Shadow 200 vehicles were delivered, but no date was given.

The announcement ends speculation over Australia's purchase and also that it was a done-deal at the Farnborough Air Show in England last month.

The U.S. government's Defense Security Cooperation Agency notified Congress in May of a possible foreign military sale to Australia of two Shadow 200s and associated equipment, parts and logistical support for around $218 million.

A number of options were on the table alongside the U.S. government proposal, including a Thales bid to lease Israeli-made Hermes 450s to Australia.

The Elbit Systems Hermes 450 is a medium-sized, multi-payload UAV for tactical long-endurance missions. The 20-foot-long vehicle, with a wingspan of 34 feet, is powered by a Wankel 52 hp engine and can fly for more than 20 hours.

Hermes 450s are operated by the U.S. Department of Defense Joint Unmanned Aerial Vehicles Test and Evaluation Program at the Naval Air Station Fallon. Several Hermes 450s were tested by the U.S. Border Patrol in 2004.

The U.S Army, Navy and Marines were operating more than 115 Shadows at the beginning of this year.

Last month AAI announced that Italy's Directorate of General Aeronautical Armament within the defense ministry had bought four Shadow 200s for the army in a $64 million deal. The vehicles will be used in NATO operations.

AAI Corporation, founded in 1950, along with its indirect wholly owned subsidiaries Aerosonde and ESL Defense, has been a part of Textron, Inc. since 2007.