The first F-35C to land, CF-03 from Navy Air Test and Evaluation Squadron VX-23, touched down at 12:18 p.m. after flying out to the carrier from Marine Corps Air Station Yuma, Ariz. Flown by Navy test pilot Cmdr. Tony 'Brick' Wilson, the aircraft first made a low approach and overshoot, followed by a touch-and-go with the tailhook retracted. Finally, with an F/A-18F acting as chase, Wilson brought the F-35C in for the first arrested landing. A second aircraft, CF-05, arrived less than an hour later and landed successfully at 1:11 p.m. flown by Lt. Cmdr. Ted 'Dutch' Dyckman.
Both aircraft made highly stable approaches, and trapped firmly on the third of the Nimitz's four arrestor wires. The touchdown spot between the second and third wires is considered the optimum for carrier landings. The landing was also key test for the F-35C's arresting hook system, which had to be redesigned with additional stiffness, a modified hold-down damper and revised shaping after poor performance in tests three years ago at Naval Air Warfare Center Lakehurst, N.J. Having delayed the start of carrier trials, the performance of the redesigned hook was a significant watch item. "It's a little bit different of a design, and obviously it works," says U.S. Pacific Fleet, Naval Air Forces Commander, Vice Admiral David Buss.
Although calm seas and light winds from the northwest contributed to the benign conditions and resulting trouble-free landings, both pilots partly attributed the precision touchdowns and stable approaches to the F-35C's integrated direct lift control feature. Embedded in the flight control software for all three JSF variants, test pilot Wilson says direct lift is particularly useful for the F-35C because it provides greatly improved glide slope control.
Unlike conventional carrier aircraft in which the pilot approaches the carrier with flaps set at a fixed position and adjusts power and pitch attitude to stay on the glideslope, the F-35 system controls power through an 'auto-thrust' function and alters the position of the trailing edge flap in response to the pilot's inputs. "So the stick becomes my glideslope controller," notes Dyckman. "If I pull back the flap adds lift, if I push forward it commands a steeper approach," he says. As nominal flap position for a carrier approach is 15 degrees, or half-flap, this provides ample margin for additional flap movement to add or reduce lift. Wilson says the effect is to "change the 'heave' of the aircraft, rather than the pitch."
"I was watching the angle-of-attack indicators," says Senior Chief Petty Officer Alistair McIntyre. ''As they came in (to land) from the break it was perfect green all the way in. It was stable all the way in for both approaches. I was amazed for that being their first time landing on the carrier as it looked like both pilots were old pros at landing F-35s. They came in on the glideslope and landed with no problems. It felt like we'd been doing this for a long time."
The landings marked the start of a two-week Developmental Testing I (DT-I) phase for the F-35C which will evaluate primarily daylight carrier operations including launch and recovery handling with a variety of crosswinds and wind over deck speeds. Catapult tests will evaluate the take-off characteristics across a broad range of excess speed settings varying from a minimum of around 5 kt. to a maximum of about 45 kt. "We will gradually expand the operational envelope," says Buss. "Having two aircraft will give us the ability to move them around the carrier, and look at the first set of results as we change the wind envelope and wind directions. If we can get all these things done in time then from Nov. 13-16 we may have the first night time operations," he adds.
Results will be built into the next test phase, DT-II, scheduled for September 2015. This will include additional day-night operations, initial weapons trials with internal and external stores as well as maximum power launches from both the bow and waist catapults. A third and final DT-III phase is expected in the March-April 2016 timeframe. The U.S. Navy anticipates declaring initial operational capability of the F-35C in August 2018 with the first squadron expected to embark on an as-yet-unnamed West Coast-based carrier earlier that year.