X-47B aborted third landing attempt

As every good seaman knows, a salty dog is an experienced sailor savvy enough to do the right thing when confronted with a problem. That’s exactly what the Navy’s X-47B unmanned aircraft — with the call sign “Salty Dog” — did when an onboard computer failed as the drone attempted its third arrested landing on theUSS George H.W. Bush aircraft carrier off the coast of Virginia yesterday.

The X-47B already had completed two landings, including the historic first carrier landing of an unmanned aircraft on a flight from Naval Air Station Patuxent River.

The second landing followed less than an hour later after a launch from one of the carrier’s catapults. After a second catapult launch, the drone zoomed around for yet another landing. That’s when one of three redundant onboard computers failed, four miles from the carrier deck, as the aircraft approached for its third landing.

In a briefing for reporters Thursday, Rear Adm. Mat Winter, program executive officer for Unmanned Aviation and Strike Weapons, said the aircraft’s computers constantly poll each other’s health. When two computers detected the failure of the third, the aircraft executed an “autonomous wave off” — it pulled up and awaited instructions from an onboard, human mission control operator.

Due to safety considerations, flight testers decided to forego the third carrier landing and directed the X-47B to land at NASA’s flight facility at Wallops Island, which was closer to the carrier than the Navy’s Patuxent River facility. Winter said the failure of the computer wasn’t a big deal in a test program. “As in every test, we have some anomalous behavior,” he said.

http://www.nextgov.com/defense/2013/07/unmanned-aircraft-aborted-its-third-carrier-landing-attempt-following-computer-failure/66488/