Osprey Gearbox Issue Cited In Deaths Of Airmen

"A "catastrophic" gearbox failure caused an Osprey aircraft to crash off the coast of Japan last year, killing all eight personnel aboard, though crew actions also contributed to the accident, the U.S. Air Force said Thursday.

The Air Force's V-22 Osprey model that crashed Nov. 29 near Yakushima island was on a routine training mission from Yokota Air Base. The remains of seven crew were recovered; the eighth wasn't found after a 43-day search.

The U.S. military's fleet of more than 400 V-22 Ospreys -- built by a joint venture between Boeing and Textron's Bell unit -- was grounded for three months following the crash. In 11 crashes involving the aircraft since 1992, 61 U.S. service members and other passengers have died.

Ospreys have an unconventional design with a tilt-rotor that allows the aircraft to fly like a helicopter or a fixed-wing propeller plane.

The V-22's design and long-running issues with the gearbox have attracted congressional scrutiny and criticism from the families of those killed.

While Ospreys are back in the air, the Pentagon has said that they won't be cleared for use over extended distances before mid-2025 at the earliest. 

A new clutch is being developed for Osprey engines to address long-term gearbox issues.

The initial problem with the Osprey that went down in November came when a gear cracked some 40 minutes into the afternoon flight, dispersing metal fragments and triggering a cockpit warning, according to the Air Force's 55-page accident investigation report released Thursday.

The malfunction didn't immediately cause the aircraft to crash and four more warnings followed as the crew tried to troubleshoot the issues. The final warning signified a need to land the plane as soon as possible, according to the report.

The pilot said on a cockpit voice recording that he believed the previous warning signals were false alarms after another cockpit signal indicated an error.

A cascade of mechanical failures 49 minutes after the first warning led the aircraft to roll over a half mile from the runway, crashing nose down into the water.

A lawyer for the families of two airmen said that while it was natural to scrutinize the actions of the crew, there was likely little they could have done.

The crew's "decisions were made under extreme pressure" and the plane was ultimately unrecoverable because of the mechanical failure, said Tim Loranger, a senior partner at Los Angeles-based law firm Wisner Baum.

Boeing and Textron said Thursday that they remained saddened by the loss of the airmen and would work closely with the Pentagon to ensure the safe operation of the Osprey fleet. Engine-maker Rolls-Royce declined to comment.

The law firm has filed a lawsuit alleging negligence against Textron, Boeing and Rolls-Royce over the fatal crash of an Osprey in California in June 2022 that killed five Marines. The three companies have denied the allegations, according to court filings.

The Osprey is a military workhorse, especially in the Marine Corps, because of its unique attributes. It can fly up to 300 miles an hour for more than 400 miles while carrying up to 24 people. The latest versions cost $120 million each and are due to fly until 2055.

The Army last year selected a similar tilt-rotor design to replace part of its Black Hawk helicopter fleet, awarding a contract to Textron that analysts estimated could be worth up to $70 billion.

The new craft, the V-280 Valor, can fly faster and farther than the Osprey." [1]

1. U.S. News: Osprey Gearbox Issue Cited In Deaths Of Airmen. Cameron, Doug.  Wall Street Journal, Eastern edition; New York, N.Y.. 02 Aug 2024: A.3.