Boeing

Two new U.S. Marine Corps weapon systems recently demonstrated their compatibility here when the V-22 Osprey lifted for the first time a prototype of the Lightweight (LW) 155mm Howitzer.

This test flight was a cooperative effort between the V-22 Program and the Joint Marine Corps and Army Howitzer Program offices to show that the next generation LW155mm Howitzer, designed to replace the aging M198 Howitzer, could be carried by the Marine Corps' new tiltrotor aircraft.

The two were linked together while the Osprey hovered about 4.5 feet above the 9,320 lb. LW155, which was then lifted as a single-point load using the aircraft's aft hook. The hookup was conducted by six Marines from the Helicopter Support Team 2nd Land Support Battalion, Camp Lejeune, who connected the two systems in about 60 seconds.

"The 155mm dimensions make it easier to hook up than the gun it will replace because it is shorter, the base is smaller and the barrel angle is less steep," said Sgt. Jerald Cleveland, the Helicopter Support Team lead. Cleveland added that with its overall length of 402 inches and overall width of 146.5 inches, the LW155mm has a smaller footprint than the M198, making it easier to move around and providing greater clearance between it and the V-22.

After the hookup, the V-22 lifted the Howitzer and hovered for about 25 minutes to demonstrate lift and handling characteristics while in vertical flight. "It was a very predictable and stable lift. In the hover mode, the load was well-behaved," said Larry Smith, V-22 flight test engineer who works on the external loads program.

The LW155mm, like the V-22, is still in the engineering, manufacturing and development phase. Once production begins in 2002, the Howitzer will again be lifted by the V-22 so it can be certified for transport by the Osprey. While the Howitzer is not a requirement for the V-22 to lift, the gun's design will be compatible with the V-22 and other vertical lift platforms to include the CH-53 and the Army's CH-47. Missions in which the V-22 would transport the LW155mm are amphibious and land assault. In these missions, the Osprey would carry the Howitzer from either ship- or land-based positions to a forward point to support land troops.

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