The US Marine Corps will consider replacing its radar-jamming Northrop Grumman EA-6B Prowlers primarily with a new class of unmanned aircraft systems. For several years, the USMC's unofficial replacement plan involved modifying Lockheed Martin F-35Bs with next-generation jammer pods, but its thinking appears to be opening up to new ideas.

The USMC's future Tier III UAS fleet, now reclassified as the "Group 4" aircraft, is an option for the EA-6B's electronic attack mission, and "may end up taking a good bit of that role", Maj Thomas Heffern, the service's UAS capabilities officer, told the Association for Unmanned Vehicle System International's Unmanned Systems Programme Review on 3 February.

Requirements for the Group 4 UAS have gradually evolved. Bell Helicopter's Eagle Eye tiltrotor was an early candidate before a series of crashes cancelled the programme. The Boeing A160 Hummingbird, a long-endurance, vertical take-off UAS, has also been proposed.

But the USMC is still interested in even more radical proposals for the Group 4 requirement, and vertical take-off may no longer be a necessary feature, with a short take-off and vertical landing capability also listed as a possible option.

Instead of take-off mode, speed and modularity are becoming the key drivers for the programme. A notional speed requirement is 250kt (462km/h), but this must be balanced against the USMC's need for 10h to 24h endurance on station.

"More [speed] is always better from the Marine Corps' capability standpoint," Heffern says, adding that industry should look back to "technologies available in the 1960s that weren't able to evolve".

Besides electronic warfare, the USMC wants the regiment-level UAS to perform the roles of intelligence, surveillance, reconnaissance and target acquisition (ISR/TA), plus persistent strike, communications data relay and command and control.

The USMC, however, is open to proposals that would allow the same aircraft to carry a 725kg (1,600lb) cargo payload. Heffern raised the idea of a multirole Group 4 UAS that could perform the ISR/TA, strike and cargo missions.

Another key requirement for the aircraft will be its noise signature, Heffern says, as an aircraft performing the ISR mission must not loud enough to be detected from the ground.

Source: Flight International