Fighter pilots do much of their warfighting work at night, when targets are lulled by sleep and the jets can take cover in the embrace of darkness.
That capability was on display during the past three weeks of F-35B testing aboard the Norfolk-based amphibious assault ship Wasp. The next-generation Marine fighter jet conducted 19 nighttime takeoffs and landings -- demonstrating its remarkable ability to slow to a hover and drop with precision onto the flight deck of an amphibious ship in the middle of a dark ocean.
It was a milestone for the $400 billion joint strike fighter program, which is developing three versions of the jet -- to operate from land, from amphibious ships, and from aircraft carriers. The planes have been in development for more than a decade but are years from operational use.
"Our primary striking power and posture comes at night," said Navy Capt. Erik Etz, director of testing and evaluation for Navy and Marine Corps variants. "So the ability to operate the F-35B at night from the ship provides that capability for this aircraft to augment forces abroad."
But there's a catch: Night-vision capabilities on the F-35's revolutionary integrated helmet system fall short of requirements and are inadequate for shipboard vertical landing or nighttime refueling.
"The helmet's been a problem, no doubt," said Brig. Gen. Matthew Glavy, assistant deputy commandant of aviation for the Marine Corps.
The helmet-mounted display is key to unlocking the technological systems built into the plane -- allowing the pilot to view a kind of virtual reality through the aircraft's many cameras.
The F-35's "fusion" system processes all the data collected by the airplane -- movement on the ground, possible enemy targets, the approach of enemy aircraft -- and projects it onto a display screen built into the visor, so the pilot sees it all in real time.
Walking around the aircraft on the deck of the Wasp on Wednesday, Lt. Col. Matt Kelly, a former F-35 test pilot now working in the program office, pointed to a transparent enclosure under the nose of the plane containing two rounded chrome-and-glass sensors.
The F-35 is the only stealth aircraft to have this kind of electro-optical targeting system built in, allowing it to remain stealthy, he said. It works in conjunction with radar and the cameras embedded in the plane.
"One of the key attributes of the F-35 is, it is designed to collect information through its multiple sensors," Kelly said.
All that information is transmitted to the pilot through the helmet.
Over the past year, testing of the helmet revealed a series of problems, Lt. Gen. Christopher Bogdan, executive officer for the F-35 development program, told the Senate Armed Services Committee in April.
Some problems -- including a green glow, jittery symbols and a time lag in displaying information -- have been resolved. But the night vision remains troublesome, and an alternative helmet is being developed based on night-vision goggles, he said.
Lockheed Martin and BAE Systems are competing to design a helmet, Glavy said.
Because of the unique challenges of operating on an amphibious ship, the F-35B has proved to be the most costly to develop for the services. Its purchase price is an estimated $110 million in 2018, compared with $96 million for the Navy version and $85 million for the Air Force version.
During three weeks on the Wasp, two F-35Bs conducted more than 90 takeoffs and landings on the small amphibious deck. On Wednesday, when the Navy flew journalists aboard the Wasp for an F-35B demonstration, both jets were down for maintenance. One was quickly repaired and took off later the same day, program officials said.
The planes also "pushed the envelope" in other ways, flying in stronger winds and carrying dummy weapons to simulate how the aircraft handles with its payload.
In those things, the jet "is matching expectations in ease of handling," Etz said.
Some of the Wasp crew spent time at Patuxent River Naval Air Station training to work with the F-35B either in maintenance or on deck.
"As much as the aircraft evolves, the ship evolves with it," said Petty Officer 2nd Class Matthew Bennett, who directs the rear half of the flight deck.
"It's a pretty prestigious event," he said. "We are kind of going down in history with this jet."