The RAF will take delivery of its first Protector, a Medium Altitude Long Endurance (MALE) Remotely Piloted Air System (RPAS) this year and should achive Full Operating Capability by 2024. Protector is a modified MQ-9B SkyGuardian UAV made by General Atomics-Aeronautical Systems-Inc (GA-ASI) and will be used for armed ISTAR, carrying Brimstone missiles and Paveway IV Laser Guided Bombs. 16 Protectors will replace the legacy Reaper fleet and the UK contract with GA includes the option for a further 13.
As part of the FMAF, the RN envisions operating a land-based Maritime Protector variant. GA has developed the SeaGuardian derivative of the MQ-9B with a range of 6,000nm, able to stay on station for up to 25 hours, it has nine hard-points for a sensor or weapon payload of up to 2,100 kg. SeaGuardian can be equipped with a variety of maritime radar and EO sensors and even conduct ASW when equipped with a sonobuoy dispenser. Whether the UK will purchase SeaGuardian for this requirement is unclear for now but with Protector already in service, it would make sense as there would be commonality of logistic support and training. Although a US-made product, the Protector deal includes the involvement of British industry. For example, Isle of Wight-based GKN Aerospace now manufactures the V-tails for all MQ-9B variants.
The MQ-8B has a modular design and, to facilitate STOL operation the long tapered wings and tail planes of the base model are replaced. The STOL kit can be installed in less than a day and the core aircraft and its sub-systems remain the same. Kit includes non-tapered wings with a thicker aerofoil section that generates more lift at low speed. Their wingspan is slightly reduced and are power-folding to save deck and hangar space on the ship. The propellor has also been modified to produce greater initial thrust needed for take-off.
The re-designed wing and propeller reduce the take-off length required but will inevitably have a modest range penalty due to increased drag. Flight profile will vary depending on payload and weather but the GA simulation shows the MQ-9B making an unassisted taking off using less than 250m of deck and an unarrested landing using less than 200m. Of course, this concept has yet to be demonstrated at sea and there are many potential issues to resolve before this is a viable operational capability for any navy.Sea-Guardian-STOL-modifications
Despite its long range, the possibility of operating a MALE UAS from an aircraft carrier has a lot of attractions. As an organic part of the airgroup it would be fully globally deployable and responsive to the immediate mission requirements of the carrier strike group. STOL MQ-9B could perform several roles. Its range and persistence would make it ideally suited to replace the Merlin-helicopter-based Crowsnest Airborne Surveillance and Control task. Project Proteus initially envisaged a rotary-wing UAS as the solution but a fixed-wing UAS would have vastly better endurance and service ceiling. (MQ-9B can operate up to 40,000 ft compared with the 15,000 ft of a Merlin).
A SeaGuardian-based solution could also act in the ASW ‘find’ role, supplementing the overstretched Merlin force with a sensor platform that can be airborne for days instead of hours. If armed, the MQ-9B could be used in the strike role to support amphibious operations. Integration with other UK weapons such as Sea Venom or Spear-3 also offers other possibilities to increase the reach of the carrier group. As a slow-moving RPAS, MQ-9B is theoretically not likely to survive long in contested airspace but in the ISR role its vulnerabilities are little different to a Merlin or MPA and more risk can be taken with an uncrewed platform. It is interesting to note that less sophisticated Bayraktar TB2 RPAS have excelled in combat in Ukraine despite Russian air defence capabilities.
The RAF recently cancelled Project Mosquito by mutual agreement with the industry following a technical review. This was a technology demonstrator to develop a ‘loyal wingman’ uncrewed air vehicle for F-35 and Tempest. The RN’s Project Vixen was considering a carrier-based loyal wingman, potentially a Mosquito derivative, this is a complex requirement that would require substantial modifications to the carrier to launch and recover these UAVs.
The ambition for Mosquito always seemed wildly optimistic in relation to the technical requirement – an autonomous jet capable of matching F-35 flight profiles with just £30M funding for a prototype supposed to be flying by next year. It may not be a bad thing that Mosquito was abandoned. An iterative ‘fast to fail’ development philosophy avoids wasting time and money on blind alleys. There are other more advanced loyal wingman projects in the US and Australia that the UK could potentially buy into and this does not necessarily signal the end of Vixen. What it does highlight is that STOL Maritime Protector, based on proven technology and not requiring major modification to the ships, could be a faster route to carrier-based uncrewed aircraft (although obviously fulfilling a different role to Vixen).
GA-ASI has already invested considerably in ensuring that the MQ-9B can be safely operated in civilian airspace. Building on the experience gained flying MQ-9A Reaper since 2012, Protector will be based at RAF Waddington and must also be able to navigate UK airspace. During a 2-week airspace integration trials activity in September 2021 SkyGuardian conducted a number of test flights around the UK and the Netherlands was certified as safe. Although Protector will mostly be remotely piloted by aircrew on the ground at Waddington, it is capable of automated take-off and landings and has detect/avoid radar system to deconflict with other aircraft. During the trial, SkyGuardian was treated as any other crewed aircraft would be in controlled airspace by the National Air Traffic Control Service (NATS). Aircrew at Waddington communicated with NATS as they would in the air and when in uncontrolled or military airspace, they were managed by RAF 78 Squadron controllers.
A Protector crew comprises of 3 personnel a Pilot, Sensor Operator and Mission Intelligence Operator. Potentially a carrier-based MQ-9B could be flown either from Waddington or from a containerised mission module installed on the ship but this would likely require investments in greater satellite connectivity and data bandwidth for the ship. GA-ASI intend that the STOL version would be integrated with the US Joint Precision Approach and Landing System (JPALS) that was certified on HMS Queen Elizabeth in March 2021. This provides electronic guidance to aircraft landing on the ship and is integrated with the F-35. This will be especially important in the further development of Shipborne Rolling Vertical Landing (SRVL) allowing the F-35B to land flying forward to provide extra lift to recover to the ship with unused weapons.
MQ-9B will be flown by satellite link for the majority of the time but a local line-of-sight data link will most likely be needed for carrier landing, launch and flight deck movements. This will require significant integration work on the QEC such as steerable antennas, communications and command workstations. The control logic for the aircraft during take-off and landing will have to be resolved, whether fully automated or piloted. How the aircraft reacts to the pitch and roll of the ship and turbulent winds are part of the complex technical challenges that come with naval aviation. With a low-power engine and large wings, the MQ-9B is likely to have a much smaller safe weather operating envelope, being more susceptible to crosswinds and turbulent air than either the much heavier and more powerful F-35 or Merlins.Sea-Guardian-QEC-Carrier
While having the obvious benefit of avoiding the overheads involved in the fitting of catapult and arrestor gear, there are big questions, particularly around the safety of recovering the aircraft. Getting off the deck is not especially complicated although whether before the ramp or from the ramp would have to be resolved. Bringing the aircraft to a controlled stop with only reverse thrust on the propeller and brakes on the small landing gear to help looks challenging, even in moderate sea conditions. An angled deck could be the only safe solution to ensure the aircraft does not run into other parked aircraft or personnel. Although the QEC has plenty of space, how the MQ-9B affects the operation of other aircraft would have to be carefully calculated. There are also a wide range of other details that the integration team would have to consider such as how well marinised is the airframe.
Carrier-based Maritime Protector appears to be a useful option for the UK naval aviation but, like the majority of the FMAF elements, is merely an unfunded possibility with potential at this stage. It would be especially attractive if the US Marine Corps decide to adopt this platform which could allow the costs of de-risking and integration to be shared.