Precision without precedent
Built for rough seas, it can help the US Air Force in mountains and desert
The same technology that now guides aviators onto the decks of aircraft carriers in roiling seas will do the same for the U.S. Navy’s future unmanned tanker. One day soon, it may also help U.S. Air Force pilots land on austere runways in remote regions of the world.
The Navy will use the Joint Precision Approach and Landing System — JPALS for short — to land the MQ-25 unmanned aircraft onto carriers at sea, quite a feat without a human at the controls. Known as the Stingray, the Navy’s future unmanned carrier aviation air system will provide in-flight refueling to the U.S. fleet’s fighters, allowing them to operate at far greater ranges than before.
“When you’re talking about auto-landing a flying unmanned tanker onto an aircraft carrier, then the system has to be infallibly accurate, which JPALS is,” said Mark Maselli, Raytheon JPALS deputy program manager.
JPALS is a differential, GPS-based precision landing system that guides aircraft onto carriers and amphibious assault ships in all weather and surface conditions up to the rough waters of Sea State 5. It uses an encrypted, jam-proof data link, connecting to software and receiver hardware on the aircraft and an array of GPS sensors, mast-mounted antennas and shipboard equipment.
Early in 2018, U.S. Marine Corps F-35B Lightning II fighters, deployed to the Pacific aboard the USS Wasp amphibious assault ship, used Raytheon's JPALS to guide them onto the carrier’s deck in extreme weather and surface conditions. The system will go into production in 2019 and will be outfitted on the U.S. Navy’s newest fighter — the F-35 Lightning II.
“We’re asking our pilots to land in some of the most difficult conditions on Earth,” said U.S. Navy Captain B. Joseph Hornbuckle III, program manager at the Naval Air Traffic Management Systems Program Office. “JPALS goes a long way toward ensuring the safety of our aircrews and the success of our missions.”
Landing a jet on the deck of an aircraft carrier is a high-stakes, harrowing business, even on calm seas.
"A jet landing on the deck of an aircraft carrier goes from about 150 mph to zero in seconds. There's little to no margin for error, and JPALS makes one of the most dangerous activities on a ship a lot safer," Raytheon's Maselli said. "We’ve got a 20-centimeter vertical accuracy requirement, so that hook hits the wire every time. We never want the pilot to miss that and have to bring the jet back around again."
In 38 attempts in one test, Maselli said, the aircraft captured the wire every time.
INTO THE WILD BLUE YONDER
JPAL’s precision navigation is equally effective ashore. Raytheon is developing an expeditionary version of the system that is small enough to either be air-dropped or driven into austere environments.
The military could rapidly deploy JPALS to a remote location to support contingency operations such as countering a new threat or helping an aircraft provide humanitarian relief. This deployable version of the system could simultaneously control up to 50 airplanes out to a radius of 20 nautical miles.
According to retired Air Force Col. JW Watkins, Raytheon business development manager in the Dallas/ Fort Worth region and a former fighter pilot, deployable JPALS would support the Air Force's Concept of Operations document, especially in U.S. Air Forces in Europe that uses "dispersed operations," and the Pacific Air Forces that has an "adaptive-basing" concept of operations.
"This system comes in three pallets, with a 60- to 90-minute setup, which is a smaller package, and it can be operational very, very quickly," Watkins said. "Besides the small scale and rapid setup, it's got significantly greater capability. Not all approaches are simple straight in approaches where you drive a single heading into an airfield and land. Sometimes, based on the terrain, like mountains, you're going to need to fly a curved approach or a multi-segmented approach. It's a much more complex approach than just a simple straight in, and JPALS allows you to do that."
Watkins believes JPALS will allow commanders to quietly send in a contingency response group to help set up a bare-bones base, with advance troops, air traffic controllers and critical personal and equipment.
And just like the harrowing landings that F-35s make at sea, JPALS can help Air Force pilots land in zero/zero conditions — zero visibility, zero ceiling.
“JPALS has the potential of ensuring a pilot’s safety in places where radars find it difficult to operate like highly mountainous terrain or desert sandstorms,” said Michelle Patrick, Raytheon director of navigation and landing systems. “If I were a pilot and facing zero visibility, I’d want to be using JPALS.”