Unmanned aircraft are most often viewed as augmenting manned aircraft, perhaps eventually replacing some of them, but a more likely future lies in their becoming intimately essential to each other. Two new U.S. research notices give hints of such an outcome.

One envisions manned bombers and transports becoming flying aircraft carriers, launching and recovering small UAVs to extend their reach. The other imagines fleets of throw-away aircraft overwhelming and punching through anti-access/area-denial (A2/AD) defenses to enable stealthy but scarce assets to engage the enemy.

These are requests for information (RFI)—market surveys, not programs yet—that appear to have been switched at birth. The “affordable, attritable aircraft” is the far-out vision of the Air Force Research Laboratory (AFRL), not the Defense Advanced Research Projects Agency (Darpa). The concept of an airborne UAV carrier, meanwhile, seems somewhat prosaic for an agency that prides itself on tackling only “Darpa-hard” problems.

AFRL’s RFI seeks ideas for unmanned aircraft that could be produced and configured on demand at a cost low enough that the Air Force could afford to lose many of them in combat. The unit cost target is $3 million, compared with $100 million for a stealth fighter, with the goal that such cost be independent of order quantity and production rate.

That cost goal makes the concept closer to Raytheon’s under-$400,000 Miniature Air-Launched Decoy Jammer (pictured) or $1.4 million Tactical Tomahawk cruise missile—both unmanned and expendable—than to a light attack/reconnaissance aircraft such as Textron AirLand’s two-seat, twin-engine Scorpion, which costs $20 million but is not stealthy.

AFRL sees two key challenges. One is designing an aircraft that can actually perform an A2/AD mission while remaining modestly sized and affordably priced. The other is designing for commoditization, with manufacturing processes that enable rate- and quantity-independent production costs so the price is essentially the same for tens or thousands.

Low-cost, high-volume combat aircraft have been proposed before, but foundered on the fact that pilots are expensive and not attritable. And while production of a relatively simple design can be ramped up rapidly, combat pilots cannot be trained quickly. To overcome this, the attritable aircraft would be unmanned and air-launched from manned platforms, recovering to a base for reuse—if it survives.

AFRL makes some key assumptions: that there is no service-life requirement; airworthiness rules are relaxed; mission reliability is orders of magnitude less than for manned aircraft; there is no depot maintenance, and support is limited to component replacement and quick repairs in the field. Each vehicle has a single role, a unique configuration for each mission, and a family of systems aggregating into a combat capability. Crucially, mission types and performance are still undefined, AFRL says.

Nonetheless, the lab wants ideas on existing aircraft that could be easily and affordably modified for an A2/AD mission and flown in 12-18 months, and clean-sheet designs that could be demonstrated in 18-24 months. And it wants industry input on whether either could be produced for $3 million or less.

Darpa, meanwhile, believes bombers or transports launching and recovering fleets of small UAVs could enable new missions involving distributed operations by collaborating platforms. Small unmanned aircraft could reduce the risks faced by expensive manned aircraft, but lack the speed, range and endurance required. A blended approach, in which large aircraft deploy multiple cooperating small UAVs, could extend range, increase safety and cost-effectively enable new capabilities, Darpa says.

The agency is seeking concepts and technologies for airborne launch and recovery of low-cost reusable UAVs involving minimal modification of existing large aircraft types, such as B-52 and B-1 bombers and C-130 and C-17 airlifters.

In the mid-2000s, the Air Force studied a concept called Just-in-Time Strike Augmentation that involved launching large numbers of a networked long-endurance weapon, the Area Dominator, from C-17s to break the back of enemy operations. A C-17 was to carry 600 weapons on pallets, 60 of which would act as network gateways for the strike vehicles. Boeing built and flew Dominator demonstrators.

The agency also is seeking proposals for full-system flight tests within four years, “to assist in planning for a potential future Darpa program,” and to demonstrate functionality to potential service partners that could transition the system to operation. That may prove the Darpa-hard part.

aviationweek.com