Short Takeoff and Landing Capability Delivers Critical Mission Flexibility to UAS Ops

Uncrewed aircraft have been changing the world for decades now – but they’ve never stopped evolving.

A new wave of aircraft and capabilities is poised to usher in another era of expanded roles and missions. One of the most exciting is short takeoff and landing, also known as STOL. These STOL platforms enable highly expeditionary operations which have become more relevant to many defence forces, including to the New Zealand Defence Force.

Industry leader General Atomics Aeronautical Systems, Inc. (GA-ASI), based in San Diego, is developing new models of STOL uncrewed aircraft that offer tremendous endurance, sensing, versatility and other benefits of today’s leading medium-altitude, long-endurance uncrewed aircraft, with much greater flexibility about how and where to employ them.

Leading the way has been the company-designed, company-built demonstrator called Mojave. This aircraft is a demonstrator variant of GA-ASI’s Gray Eagle uncrewed aircraft with different wings, tails and engine, and tougher landing gear. By trading off a small amount of the maximum endurance of the older model, Mojave has shown it can take all the traditional capabilities almost anywhere.

Mojave has taken off and landed from very short runways; from unimproved surfaces in the desert; from a warship at sea. In the spring, it destroyed a number of static targets in a live-fire test at a test range in Southwestern United States. These achievements have generated a great deal of international interest in the forthcoming production model –Gray Eagle STOL (GE STOL).

The STOL advantage

The STOL approach solves a problem that has been identified the world over: how to build an uncrewed aircraft that provides the best intelligence, surveillance, reconnaissance, and other roles such as contested logistics, but which also does not depend on a large, fixed, traditional air base.

Large bases tie operations to one area. They’re easy to surveil and necessitate predictable patterns of operation and life. They provide easy, unmoving targets to adversaries, which can be difficult to defend. That’s why military services are interested in systems that let them gain more independence and flexibility.

Many prospective solutions have been offered – most of them unsuccessful. Catapult-flung, tubefired, rocket-blasted, vertical take-off

(VTOL), or other novelty launching systems don’t need runways, but also cannot do what is necessary: the aircraft that use them are too small to carry enough fuel to fly for very long and don’t have a useful payload.

What GE STOL offers is an aircraft with very short ground roll that doesn’t need a paved runway, but which also boasts around 25 hours’ endurance, depending on its payload, and provides class-leading full-motion video, synthetic aperture radar and other sensing. Multiple networking capabilities mean the aircraft could be operated from its forward location or it could be flown by satellite from a ground control station that can be located anywhere in the world.

There are a huge number of applications: GE STOL might take off from a home station air base and fly to a distant forward location where a small number of troops had already set up an austere expeditionary base. With a plot of grass, a straight section of beach, or a neighborhood football pitch, the detachment could have its own landing strip.

The aircraft might provide armed overwatch, mission escort, reconnaissance, or serve other tactical whole-of-government roles. GE STOL also is on the forefront of a new mission set gaining increased attention from the U.S. Army and its international partners: a concept called contested logistics.

In a conventional land conflict, two competing forces might face each other along a forward line of troops, or across a geographical boundary such as a river or mountain range and control all the territory back from it on each side. Tomorrow’s conflicts, however, might not be so simple – friendly forces might need to occupy islands, including perhaps man-made ones, within larger sections of contested territory or waterspace. In that event, the basic job of keeping them fed, armed, and equipped gets much more complicated.

The GE STOL “truck”, with its ability to carry a 1,000-pound payload over tactically significant ranges, can be part of the solution: the aircraft might take two cargo pods through contested territory to friendly forces, land briefly to drop them off, and then quickly take off again. The aircraft could remain overhead to patrol for hostile forces, take another mission or return to base. An additional “truck” role for the GE STOL is for the aircraft to carry smaller UAS, which in turn can carry smaller UAS such as a loitering munitions into contested and/or denied airspace. This concept of operation extends the range of a “swarm” of loitering munitions well beyond their operational range.

MQ-9B STOL

GA-ASI is also developing a forthcoming STOL version of its MQ-9B SkyGuardian and SeaGuardian aircraft. This aircraft will provide an even greater payload, endurance, sensing, and other capabilities over the smaller GE STOL model.

One main area of focus for MQ-9B STOL is naval operations. The aircraft’s day-long endurance will enable navies to rewrite their practices across the range of naval missions, which might include intelligence, surveillance, and reconnaissance; electronic warfare; anti-submarine warfare; and airborne early warning.

MQ-9B’s proven effectiveness at hunting undersea targets, for example, would give surface forces a huge new advantage in anti-submarine warfare. The aircraft is the only one of its kind that can release and monitor sonobuoys, holding custody of submerged targets for much longer than any human-occupied helicopter or maritime patrol aircraft due to an extended endurance.

MQ-9B also has had many successes as a communications relay for naval surface action groups. Operating high over a group of warships, the aircraft can provide high bandwidth as needed for ships and other units to share information, coordinate and conduct operations.

The aircraft also might provide escort for a surface action group before it heads into a choke point or other potentially hostile waterspace. Or it could take still other novel missions – or simply serve as a multidomain intelligence, surveillance, and reconnaissance platform for allied operations.

These aircraft can transmit highquality, full-motion color video or infrared footage any time of the day or night. With their synthetic aperture radar, they can see through clouds, smoke, haze, mist, or any other atmospheric obstruction. And a huge number of diverse payloads mean they can take on nearly any role required for an aircraft in the technically complex operating environments of the 21st century including doing the “truck” concept of operations/mission of providing a lift to the smaller “swarming” aircraft systems like the GE STOL.

Much of this already has been true for conventional mediumaltitude, long-endurance remotely piloted aircraft – which aren’t going anywhere, and which also will continue to evolve their abilities with new technologies and new types of application. The good news for today’s defence and security forces is that STOL means these aircraft can operate from more diverse and unprepared locations than ever before.

In the New Zealand context, this could translate to rapid, dynamic operations throughout the broad area of national interest where terrain can be challenging and services-limited.