History of V-22 Osprey crashes and ongoing safety issues

Another false start

Production and subsequent testing of the V-22 Osprey continued, but with weak support from Congress. But there continued to be fatal incidents.

In 2000, Marines were conducting a weapons training course aboard two Ospreys flying from Yuma Air Force Base in Arizona to Marana Regional Airport, located 25 miles outside of Tuscon, when disaster struck.

The first aircraft – call sign Nighthawk 71 – began its descent 2,000 meters too high and began a rapid deceleration, hitting the runway hard but eventually landing unharmed. The second Osprey – call sign Nighthawk 72 – also began its descent at an unsafe altitude, descending 2,000 feet per minute at just under 45 mph.

Toward the end of the rapid descent, Nighthawk 72 lost lift in its right rotor approximately 245 feet above the ground, causing the aircraft to stall and roll. The Osprey then crashed and exploded, killing all 19 Marines on board.

In an 8,000-page accident report, the Corps said “human factors” were the main cause of the crash. The report stopped short of attributing the cause to pilot error, but the head of maritime aviation told a press briefing at the time “that the pilot of the ill-fated aircraft significantly exceeded the rate of descent established by the regulations for safe flight.”

“It appears that none of the pilots recognized the danger presented by their high rate of descent and low forward speed, which is the same in any helicopter you fly,” said Fred McCorkle, then a Marine lieutenant general.

“Unfortunately, the pilot’s effort to complete this mission appears to have been the fatal flaw,” he added.

Another GAO investigation later found that in the rush to push the Osprey into full-scale production, the Navy failed to conduct critical developmental tests on the aircraft. The oversight, he said, ultimately made the aircraft vulnerable to turbulence known as the “vortex ring condition,” a potentially fatal turbulence caused by the helicopter’s rapid descent and low speed pushing disturbed air through its blades.

While the vortex ring condition is a known risk to helicopter pilots, it was unclear at the time whether the same warnings would apply to the first-of-its-kind Osprey.

It wasn’t until 15 years later that the Department of Defense issued a corrective statement after years of protest from the families of the late pilots, Navy Adm. Brooks Gruber and Lt. Col. John Brow. The Pentagon said they “had neither the knowledge nor the training to prevent the crash.”

Learning from that tragedy, future Ospreys were equipped with alerts and alarms to help prevent a repeat, and pilots and crews underwent appropriate training programs.