The Osprey's growing pains: she is high maintenance, but marines love her anyway.

• Author: Jean, Grace V.

* Marine Corps officials have raved about the MV-22 Osprey's recent contributions to operations in Iraq, Afghanistan and Haiti.

Commanders like the tilt-rotor aircraft's advanced features and performance. The Osprey, however, is as high maintenance as it gets.

MV-22 maintenance squadrons in Iraq have faced reliability and maintainability challenges "stemming from an immature supply chain not always responsive to the demand for repair parts and aircraft and engine parts lasting only a fraction of their projected service life," stated a Government Accountability Office report. The operations and support costs for the life cycle of the program, initially estimated at $75.41 billion, are expected to rise. As a leading indicator of potential increases, the GAO singled out the $11,000 cost per flying hour--more than double the target estimate.

"The Osprey's Iraq experience demonstrated that the rise in cost is due in part to unreliable parts, the cost of some parts and required maintenance," stated GAO's Michael J. Sullivan, director for acquisition and sourcing management, last year before the House Committee on Oversight and Government Reform. "If there is no improvement, overall cost and maintenance hours may remain high."

Because of the expense and labor associated with the large number of spare parts required to keep it in operations, Marine officials are now trying to come up with more efficient ways to maintain the fleet.

Classified as a medium-lift assault support aircraft, the V-22 carries 24 troops and can take off and land vertically like a helicopter but fly like an airplane. It has been operating in Iraq since late 2007 and is now flying combat missions in Afghanistan. A squadron enroute to a war zone in January was diverted to Haiti to assist with the earthquake relief operations. Officials expect the demand for the aircraft to continue growing in the months ahead.

The Marine Corps' fleet of combat-deployable Osprey aircraft in the last year has averaged an availability rate of 65 percent. The initial readiness level estimate for the aircraft had been projected at 82 percent. But since the tilt-rotor entered service three years ago, officials have discovered problems with the availability and performance of key parts.

"There are some select components that have not lived up to the reliability of the engineering predictions first conveyed," said Lt. Col. Robert Freeland, aviation plans and medium-lift requirements officer at Marine...