A cutting-edge system primarily developed to help fighter pilots land fast jets on aircraft carriers is making its Dubai Airshow debut this week - and it is being marketed for use on land.

What appears to be this counter-intuitive proposition is being made by Raytheon, whose JPALS (Joint PrecisionApproach and Landing System) is in development for the U.S. Navy, who will use it to help F-35 pilots land on carrier decks. The system, which uses GPS data to provide pilots with a landing spot measured in centimetres, will also be part of the landing technology utilized by the MQ-25 unmanned tanker program, regardless of which aircraft is selected.

Raytheon's contract with the U.S. Navy was let in 2008: the carrier-borne iteration of JPALS is currently in test, and is scheduled to achieve initial operating capability in 2019. Clues to the system's utility on land go back to the roots of the program in the 1990s, when the U.S. Department of Defense published a precision-landing requirement. In 1996, following the deaths of all 34 people on board a USAF Boeing T-43A which crashed on a non-precision approach to Dubrovnik, efforts intensified to field a system that offered that capability in a deployable form.

"The way we attacked this was to try to solve your hardest problem first," says David Ray, vice president of business development with the company's information, intelligence and services division. "If you think about an aircraft carrier that's moving, experiencing cloud, fog and other weather conditions, with a runway that's only so long - to be able to land with pinpoint accuracy is difficult. But once you've got that framework, you're able to leverage the capability across the board."

So far, the system has been flown on F-35 and F-18 aircraft, but it can be retrofitted to any platform. The hardware is mainly contained in the ship- or ground-based package, which Ray describes as "Humvee-sized": some modification may be required to the aircraft, but usually only to software of equipment already carried on board.

"The JPALS unit can talk to whatever aircraft can receive its waveform," says Raytheon consultant and F-18 pilot Brooks Cleveland. "They need GPS, which almost every airplane these days has; they need an inertial navigation system, which, again, most have; they need some spare processing power, typically found in the mission computer; and then the key piece is a radio that can recognise the JPALS waveform. That's not a new radio: it'll mean a software upgrade, or perhaps a chip in an existing radio."

The need for a new waveform has been driven by security requirements. The links between the JPALS unit and the aircraft are encrypted, and designed to have a low probability of being observed or intercepted by a third party. Unlike the hemispherical radio frequency "bubble" produced by a radar-based system, Cleveland says JPALS' RF footprint is "virtually non-existent." To further minimize any chance of detection in a deployed ground operation, the unit can be placed up to 20 miles away from the desired landing site.

JPALS is capable of guiding up to 50 inbound aircraft simultaneously, from ranges of up to 200 miles. Ray points out its utility in sandstorm or brownout conditions, which the company believes will be of interest to potential customers in the Middle East.

"This is tailor-made for special-forces-type missions," Cleveland says. "The landing site doesn't even need to be a flat surface if you had it on a helicopter. It can provide an approach to spots typically unreachable by aircraft: it can build a curved approach based on very precise GPS which allows us to go lower, and in tighter spaces than previously seen."

The system's reliance on GPS may leave it susceptible to jamming - not of the links between the unit and the aircraft, but of the signals from the GPS satellite constellation. The U.S. DoD has recognized GPS resilience as a potential area of vulnerability, and as part of its mitigations it has contracted with Raytheon for the delivery of a next-generation GPS ground station.

"Our customers will tell you that that's one of the hardest problems we've had to tackle across the DoD," says Ray. "I think the architecture that we're delivering as part of the upgraded GPS will be able to meet those needs and provide more resilience against those low-end jam threats. And because JPALS is going to be accessing the GPS system, as GPS moves to the next-generation system it will make JPALS much more resilient."