The U.S. Navy has slipped by a few weeks the release of its draft request for proposals (RFP) for the service’s project to field at least one squadron of surveillance UAVs onboard an aircraft carrier within the next decade.

The draft Unmanned Carrier-Launched Airborne Surveillance and Strike (Uclass) RFP was slated for release this month, but it is now expected to be out by the end of September, says Jamie Cosgrove, a service spokeswoman. Until that document outlines the Navy’s specific needs, debate still continues over requirements, including how stealthy the aircraft needs to be.

Industry and military sources suggest there has been discussion between the Navy leadership, military leaders on the Joint Staff and top officials in the Office of the Secretary of Defense over how the design of the air vehicle should balance payload, endurance and survivability.

The requirement of operating on an aircraft carrier puts a premium on these qualities. Rear Adm. Mat Winter, program executive officer overseeing Navy unmanned aircraft, said last month that either a stealthy, tailless design or a winged body with a tail could satisfy the Navy’s needs. He declined to outline specific requirements.

Lockheed Martin, producer of the stealthy F-35 and F-22 fighters, is pitching a tailless aircraft designed to operate in an anti-access area denial (A2AD) environment, such as that expected in Pacific countries such as North Korea or China. Northrop Grumman, builder of the stealthy B-2 and tailless X-47B Unmanned Combat Air System (UCAS), is also opting for higher-end survivability, according to industry sources.

By contrast, General Atomics and Boeing are expected to de-emphasize stealth in favor of more endurance and payload.

“What is not clear yet is how many provisions there need to be to go beyond a contested airspace [environment and] up to an A2AD environment,” says Bob Ruszkowski, Lockheed Martin’s Uclass program capture lead. “We believe that Uclass needs to be a fifth-generation capability,” he adds, referring to the company’s marketing term for a combination of stealthy shaping and avionics fusion found in the F-22 and F-35.

Lockheed’s design builds on lessons not only from those manned fighters but from previous work on the company’s Polecat unmanned aircraft demonstrator and the subsequently fielded RQ-170. This aircraft, the Sentinel, carries intelligence-collecting sensors inside a stealthy design; one of the aircraft, which is said to have little endurance, was lost over Iran last year while conducting a mission.

Stealth, however, is perceived to require higher development, production and maintenance costs. Ruszkowski says Lockheed’s experience with the F-35C is providing lessons on affordability; but that aircraft has yet to conduct ship trials.

Winter says the Navy expects to field the first Uclass air vehicle within three to six years of contract award; the service could be allowing for so much time so that the competition can be as inclusive as possible for bidders.

The Navy will likely select a cost-plus contract to minimize the amount of risk put on the contractor while developing the system, but it is unclear how the Navy will grade the bids, including prioritization of technology readiness for a set of basic, or threshold, requirements and objectives.

Lockheed is emphasizing survivability in order to provide the most flexibility to future commanders, Ruszkowski says. “It is our conviction that a recce platform like Uclass will need to operate in a variety of areas,” especially as the Pentagon places more emphasis on the Pacific region, he says. Though the Air Force’s Predator and Reaper fleets have been a mainstay in targeted attacks on high-value al Qaeda leaders in Afghanistan and Yemen, these aircraft are not able to transit areas quickly and they are not considered highly survivable in contested airspace. Producing yet another UAS without the ability to penetrate highly defended areas would contribute to a “gap” in intelligence collection in these environments, Ruszkowski says.

So, the outcome of the Uclass — whether the Navy opts for a more or less survivable system — could be an indicator of whether the Pentagon considers this program to be its front-runner intelligence collector in an A2AD environment or whether this mission will be handled by other, possibly classified, programs.

Grading so-called objective capabilities — such as extra survivability in an air vehicle — has been a challenge for services in the past several years as contractors have shown more willingness to protest source selection decisions. At issue will be how the Navy can structure a competition to place value on requirements above the threshold while also keeping cost low; Winter emphasized that affordability will be key in the competition.

This type of competition tripped up the Air Force when it originally selected EADS to provide 179 KC-45 refuelers designed to start replacing the venerable KC-135 fleet. Boeing protested the selection, which was eventually recompeted, and ultimately won a contract to build its 767-based tanker.

The Navy, however, has demonstrated prowess in conducting clean competitions. Despite a protest on its Broad Area Maritime Surveillance UAV program from a losing Lockheed Martin/General Atomics team in 2008, government auditors upheld the choice of Northrop Grumman’s Global Hawk-based aircraft.

As in that competition, the Navy is focusing part of its value equation for Uclass on the aircraft design’s “effective time on station,” or ETOS. This refers to the amount of time the Uclass will be collecting intelligence; transit time to and from its mission area is not included. At issue will be a contractor’s ability to provide enough ETOS without demanding too many aircraft on the carrier, where parking and repair space is at a premium.

More endurance, however, is not necessarily better, Ruszkowski says. Ideally, the aircraft must have endurance of roughly 14 hr., he says, to best flow with a carrier’s traditional air operations cycle. Carriers typically conduct flight operations for 12 hr. and then rest for 12 hr. The Uclass could be the first aircraft launched during the day and the last recovered, taking full advantage of the “on” cycle for the deck crew but without altering manpower requirements, he says.

Requirements are expected to demand that each carrier be able to conduct two 24-hr. Uclass orbits at once; this translates to at least four aircraft of Lockheed Martin’s design; one additional aircraft could be required as a backup.

Specific payload needs have not been outlined by the Navy. But Ruszkowski says that Lockheed is expecting to include a standard electro-optical/infrared/laser designator system capable of collecting full-motion video, as well as the ability to carry the 250-lb. Small Diameter Bomb, and possibly the 500-lb. Joint Direct Attack Munition.

A multispectral — or possibly hyperspectral — payload is also being considered. An intelligence-collecting radar, however, is not being eyed for a threshold capability.