By / June 25, 2007

Many adjustments have been made to the V-22 Osprey in recent years, but the stakes were particularly high last week when officials discovered shoddy switches in some aircraft could cause a "catastrophic" crash, Inside the Navy has learned.

Defense officials grounded all V-22 Ospreys after discovering the bad switches could create major hydraulic leaks, robbing pilots of control of the Osprey in flight.

The "serious risk" of a hydraulic failure could cause a "catastrophic event," program officials informed Marine Deputy Commandant for Aviation Lt. Gen. John Castellaw, senior Navy official Thomas Laux and other officials in an internal bulletin written in the wee hours of June 21, ITN has learned. Program officials also warned Marine Corps and Air Force squadrons not to fly their Ospreys that morning.

Navy spokesman John Milliman said the problem is being fixed and will not disrupt plans to deploy the V-22 to Iraq in September. But he acknowledged the grave danger the bad switches would pose if left uncorrected.

"An in-flight pressure-switch failure combined with a subsequent failure of a second pressure switch could result in a mishap," he told Inside the Navy.

He said some V-22s with bad switches had no reported problems, suggesting major hydraulic leaks might not be inevitable. But with the serious risk involved, the Navy is replacing all faulty switches, leaving nothing to chance. He touted the program's response to the problem.

Milliman said the first sign of trouble emerged on June 11 when a V-22, which he identified as No. 83, experienced a hydraulic leak during an "acceptance" flight at Bell Helicopter Textron's facility in Amarillo, TX. The pilot, who was already in the process of landing, observed warnings of dropping hydraulic pressure and lowering levels of hydraulic fluid, the spokesman said. Plans to deliver No. 83 to the Marines were put on ice.

"During the post-flight inspection of a noticeable leak, the crew discovered the source to be a swashplate actuator pressure switch," Milliman said.

The Marine Corps and Air Force's V-22s continued to fly for about a week while an engineering investigation was performed. That changed only after Bell and Boeing, the makers of the V-22, informed the program office of the investigation results on the evening of June 20. Milliman said officials moved to halt all Osprey flights as soon as they suspected the problem might affect more than one aircraft.

The investigation revealed an "internal seal failure" in one of two pressure switches located on an actuator, Milliman said.

Each V-22 has six swashplate actuators. Each actuator has two pressure switches.

Officials determined Bell's supplier incorrectly manufactured pressure switches designed for swashplate actuators. A "manufacturing machining error" allowed the seal to be "extruded through a gap with the piston," Milliman said. The supplier is Eaton Aerospace, said Textron spokeswoman Barbara Augone.

This led officials to temporarily ground all V-22s so they could be inspected to check for the bad switches. A formal "red stripe" message calling for the inspections was issued on the afternoon of June 21, Milliman said.

As of early Friday morning (June 22), 38 aircraft had been inspected, 10 of which were found to have bad switches. At least some of those 10 aircraft had more than one bad switch, Milliman said. The Navy estimates it may find eight more aircraft with bad switches, he said.

A total of 86 actuators are suspected to contain the faulty switches, of which 33 are estimated to be in the fleet, Milliman said.

Some V-22s resumed flying on June 21, he said, without being specific.

Osprey No. 83, which was supposed to be flown to a Marine air base in North Carolina, remains at Bell's facility in Amarillo, he said.

The fleet support team and Bell-Boeing are assembling a stock of good pressure switches from a previous configuration of actuators, Milliman said. Officials are conducting two-hour inspections for each V-22 and replacing any bad switches with compliant ones.

"We have sufficient replacement parts on hand to return the few aircraft affected by this issue to flight without impacting operational commitments," he said.

In 2000, two fatal Osprey mishaps nearly ended the program. Despite many improvements made to the aircraft in recent years, critics remain concerned about reliability, among other issues.

Marine Commandant Gen. James Conway has said the V-22 will see combat in Iraq. He has expressed optimism about the V-22, but has also said the Osprey will crash again.

"You know, I'll tell you there is going to be a crash," Conway told reporters in March. "That's what airplanes do over time. And we're going to have to accept that when it happens. And we'll hear some of the folks that are not fans of the program rise up, I suspect, when that occurs. But the fact is, it's had some tremendously safe flight in its stand up and its preparation now after learning certain lessons and [after] certain corrections were made." -- Christopher J. Castelli