View Full Version : Official: 8 to 10 Ospreys have faulty switch

06-22-07, 04:23 PM
Official: 8 to 10 Ospreys have faulty switch
By Trista Talton - Staff writer
Posted : Friday Jun 22, 2007 14:53:12 EDT

JACKSONVILLE. N.C. — Less than a dozen V-22 Ospreys are likely affected by a faulty switch that prompted the fleet to be put on an inspect-before-flight notice Thursday.

Program officials believe eight to 10 tilt-rotor aircraft carry the bad pressure switches, said John Milliman, a Naval Air Systems Command spokesman.

Some switches in swash plate actuators, which make the prop-rotors angle when they spin in helicopter mode, are faulty. The switch in question lets the Osprey’s computer system know how much hydraulic pressure is in the actuator.

The fleet, which includes all of the Marine Corps’ and the Air Force’s Ospreys, was waiting Thursday afternoon for formal approval on how to proceed with a fix.

“There are already a number of aircraft down on the flight line known to be good,” Milliman said. “We’re not anticipating that it will have an impact on operations.”

Milliman said the problem was discovered on an Osprey flight June 11. Hydraulic fluid was leaking during the government acceptance flight near the Bell Helicopter facility in Amarillo, Texas. The aircraft’s redundant hydraulic system kicked in, and the aircraft was able to land safely, Milliman said.

“They sent the switch off to get it analyzed as to why it was leaking,” he said.

Each Osprey has six swash plate actuators, three on each side. Each actuator has two pressure switches. Officials suspect 86 actuators, identified by serial numbers, have the faulty switches.

Maintenance personnel will have to remove access panels to inspect the switches.

“The known good switches have a slightly different shape than the known bad switches,” Milliman said.

Actuators with a faulty switch will be removed and the switch replaced, he said. A stock of good pressure switches is being assembled by the Fleet Support Team and Bell Boeing, the aircraft manufacturer.

The Corps has more than 40 MV-22 Ospreys, most of which are stationed at Marine Corps Air Station New River, N.C., where the first operational Osprey squadron is preparing for its first combat deployment. Marine Medium Tiltrotor Squadron 263 is headed for Al Asad Air Base, Iraq, in September.

The Air Force has six CV-22 Ospreys, including four training aircraft.