There is no doubt that today's first-ever arrested landing of the Northrop Grumman X-47B air vehicle 2 on the deck of the USS George H.W. Bush will go down in history books as a major milestone in aerospace history. (Adjust your volume as wind and engine noise was high on the ship).
But, what could be a footnote in the historical record is an anomaly that took place shortly after the first-ever landing of a stealthy, tailless unmanned aircraft on a carrier deck. It could have dampened the historical day had the system not been preprogrammed to handle a host of issues that could crop up. But, it didn't. That came later when a third landing attempt sent the aircraft ashore (more on that below).
You can read Av Week's article on the difficulty here.
After the first arrested landing, where AV 2 snagged the number 3 wire as planned, deck operators removed the arresting wire and prepared the aircraft for taxi to catapult launch position 2.
In preparation for a catapult launch, which was needed to conduct the second landing (successfully executed as planned with a hook up to wire 2) a deck operator used an arm-mounted controller to taxi the X-47B. Prior to takeoff, however, controllers tested the handoff of the vehicle's controls from this deck operator to a mission operator housed in a container in the ship's hangar. This operator would be used to send commands to the aircraft in flight. So, handoff is essential for vehicle control once the system leaves the deck.
As Navy Secretary Ray Mabus and Chief of Naval Operations Adm. Jonathan Greenert looked on from a landing over the flight deck, seconds ticked to when the X-47B should have conducted its cat-launch.
On deck, operators were unable to get a "blue light" from the air vehicle, signaling that the transfer from the arm-mounted deck operator to the mission controller in the hangar was clean. Without a precise transfer of control validated, the Navy would likely have had to taxi and park the jet, potentially spoiling the second landing attempt planned for the party of senior leaders and press.
But, program officials had at the ready a backup arm-mounted controller, which required only minutes to connect to the aircraft. They used this system to take over control of the system and conduct a clean handoff, according to Capt. Jaime Engdahl, the Navy's UCAS program manager.
Then, operators lined up the aircraft for the catapult launch. Once lofted, the X-47B was rejoined by two F/A-18s -- which flew chase during the entire test sequence July 10 -- and got back into the carrier’s standard traffic pattern and conducted the second landing.
The anomaly took so little time to resolve media didn't inquire about it during a press briefing with Mabus, Greenert and Rear Adm. Mat Winter, the Navy’s program executive officer for unmanned aviation and strike programs, following the second trap landing.
This anomaly raises some questions about hardware reliability and the ease with which the comms links can be shifted. These are critical to any unmanned aircraft earning its way into a carrier air wing, as quick deck handling is a must to ensure the aircraft doesn’t clog up the fast-paced tempo of air ops on the ship. The X-47B program was, however, a demonstration project that was never intended to field operational equipment. So, the controller issue might be easily averted with a more robust design in a future program. And, officials are likely to scrutinize the integrity of links and ease of shifting them as they plan to choose a follow-on intelligence and strike aircraft called the Unmanned Carrier-Launch Airborne Surveillance and Strike System as soon as next fall.
However, another anomaly put a quick halt to the ship-based test sequence.
Once the media and senior-level onlookers departed the carrier, the X-47B’s third landing approach was aborted after the “aircraft self-detected a navigation computer anomaly,” Navy officials say. The UCAS demonstrator then transited to the assigned, shore-based divert field at Wallops Island Air Field, Va. Navy officials say the air vehicle landed without incident.