The US Navy confirms that a Northrop Grumman X-47B unmanned combat air system-demonstrator (UCAS-D) aircraft aborted its final attempt at an arrested landing on the aircraft carrier USS George H W Bush on 15 July, 2013. The aircraft had successfully recovered onboard the giant vessel twice before, but failed to do so on its third or fourth attempts.
"Aircraft 'Salty Dog 501' was launched to the ship on July 15 to collect additional shipboard landing data," the Naval Air Systems Command (NAVAIR) says. "During the flight, the aircraft experienced a minor test instrumentation issue and returned to NAS Patuxent River [Maryland], where it safely landed."
The unsuccessful fourth attempt means that the UCAS-D programme will not be able to complete its stated goal of making a minimum of three successful "traps" onboard a carrier. The X-47B made two successful traps on the Bush on 10 July, but a third attempt that day failed when aircraft "Salty Dog 502" self-detected a navigation computer anomaly that forced it to divert to Wallops Island Air Field, Virginia.
"There were no additional opportunities for testing aboard CVN 77, which returned to port today," NAVAIR says. "This was the final at sea period for UCAS-D. The objective of the demonstration was to complete a carrier landing. The programme met their objective."
NAVAIR UCAS-D programme manager Capt Jaime Engdahl says, "We accomplished the vast majority of our carrier demonstration objectives during our 11 days at sea aboard CVN 77 in May."
With the UCAS-D carrier arrested recovery testing complete, the two X-47B demonstrators are expected to be retired to museums in Maryland and Florida in the near future. The next navy carrier-borne unmanned aircraft will come in the form of the service's Unmanned Carrier Launched Surveillance and Strike aircraft.