ABOARD USS GEORGE WASHINGTON – Two F-35C carrier variant versions of the Joint Strike Fighter (JSF) lined up Monday on catapults one and two of this aircraft carrier steaming about 75 miles off the Virginia coast. Blast doors lifted from the deck and the aircraft's control surfaces wiggled as the pilot ran through final checks. The engine revved, the launch shooter saluted and pointed go, and the jets roared down the cat tracks to leap into the air.

Once airborne, the planes circled left into the approach pattern, a maneuver known as the racetrack for its resemblance to the oval outline. Landing gear down, flaps down, the 35Cs – "Charlies" in Navy parlance – lined up on the angled flight deck and came in for a trap, or landing, aiming to catch the third of fourth arresting gear wires with their tailhook and lurch to a sudden stop.

Once on deck, the tailhook released the wire, the aircraft moved back up to the catapult, and the cycle was repeated. Over and over and over again.

And this was only Day Two of nearly three weeks of expected flight operations aboard the George Washington.

The jets belonged to Air Test and Evaluation Squadron 23 (VX-23), the Navy's premier east coast test squadron based at Naval Air Station Patuxent, Maryland, and Strike Fighter Squadron 101 (VFA-101), the first operational squadron to fly F-35Cs. This is the third series of at-sea deck trials for VX-23 – a series of tests dubbed DT III – meant to establish hundreds of operating parameters for the new aircraft, which won't enter initial operational service with the Navy until 2018.

The first at-sea tests were held in November 2014 aboard the carrier Nimitz, while DT II took place last October aboard the Dwight D. Eisenhower. DT III is meant to be the final period of at-sea testing for the new jet.

The first tests, said Tom Briggs, acting chief test engineer for DT III, focused on day carrier operations and established launch and recovery handling procedures for the flight deck crew. DT II added in night ops, weapons loading on the aircraft's internal weapons bay and full-power launches.

DT III will refine maximum power launches from all four of the carrier's catapults and work to establish operating parameters with external and asymmetric weapons loading on the aircraft's wings, along with certifying various systems for landing qualifications and interoperability. Logistics is also a feature of DT III, where an aircraft from VFA-101 will undergo an engine switchout.

VFA-101, with five aircraft, was on board to qualify 12 pilots in deck landings, said squadron commander Capt. James Christie. All the pilots will in turn become instructors, as VFA-101's mission is to become the training squadron for other F-35C squadrons.

"We're developing a syllabus," Christie said, that will be used by pilots as they transition both from training aircraft and older F/A-18s into the 35C.

That's been the mission for VFA-101 since it was established in 2012. As more pilots are trained and aircraft goes operational, unit will become the fleet replacement squadron for active-duty F-35C squadrons.

As on all carriers, pilots perform the duties of landing signal officer (LSO), watching and grading every landing. One of VFA-101's LSOs is Lt. Graham Cleveland, who is a veteran of all three F-35C at-sea tests.

Both VX-23 and VFA-101 pilots were handling LSO duties aboard the George Washington. "It takes a village," he said, as the test and evaluation and operational squadron LSOs mingled and shared opinions and expertise.

Like many of the pilots, Cleveland said the F-35C is a bit easier to fly than the F/A-18s – with a caveat.

"The 35 is a lot more easier to fly and a lot more difficult to operate," he said. "Basic flying is easy but mission systems are more complex."

VFA-101 also brought aboard a number of its support sailors, Christie said. About 65 sailors and 15 contractors with the squadron were gaining experience in deck handling and logistics work with the aircraft.

VX-23’s task is detailed and rigorous – even at times tedious – as the squadron’s pilots conduct as many as 500 launch and recovery cycles to establish a wide range of operating parameters. The aircraft’s performance with a variety of weights and loads needs to be established, including how it handles when external weapons are loaded and carried in an uneven fashion.

External weapons, of course, break up the aircraft’s stealth signatures. But, as several pilots pointed out, once an enemy’s initial air defenses are defeated stealth becomes less important, and aircraft are needed to carry heavier weapon loads on as many as three external stores stations on each wing.

But test pilots need to check how the plane handles in many configurations, including heavy weapons on one side but not the other, and different types of weapons loaded on each station.

One issue that rose during the aircraft’s development seems to have been solved. There no longer seem to be any significant problems with the tail hook, which in 2012 was revealed to have a number of reliability issues in catching the arresting wire. A redesign of the hook and its installation appears to have been successful.

Maj. Eric Northam of VX-23, the first Marine to fly the F-35C off a carrier, declared there were no problems with the hook.

"We’ve had a very successful boarding rate," he said. "One hundred percent so far."

The carrier did not need special modifications to operate the F-35C, said commanding officer Capt. Timothy Kuehhas, although there were some software upgrades to some operating systems. About 100 crew members, he said, received handling and launch procedure training in the aircraft at the Navy’s carrier flight systems test site in Lakehurst, New Jersey.

While the DT III tests represent the final carrier trials for the F-35C, the JSF program is preparing for another round of at-sea trials for the F-35B short-takeoff-and-vertical-landing variant for the Marine Corps. The new tests, program officials said, are scheduled to take place this fall from the amphibious assault ship America off the west coast.