Unmanned Bell 407 powers up

Northrop Grumman and the Textron-owned Bell Helicopter’s Fire-X, an unmanned cargo version of the Bell 407 utility helicopter was supplied external power for the first time earlier this month. A statement issued by the two companies said ‘the team applied external power for the first time to the main computers and associated subsystems for its new Fire-X medium-range Vertical Unmanned Aerial System (VUAS)’ on the Friday before last.

The Fire-X is a fully autonomous, four-blade, single-engine unmanned helicopter that combines the extended range, payload and cargo hauling capabilities of the Bell 407 and the reconnaissance, surveillance and target acquisition architecture of the US Navy’s Northrop Grumman MQ-8B Fire Scout Vertical Takeoff and Landing (VTOL) Tactical Unmanned Aerial Vehicle (UAV). What this means is the ability to carry a ‘useful load of more than 3,000 pounds – for fuel, payloads and/or cargo’ for ISR (Intelligence, Surveillance and Reconnaissance) missions of up to 16 hours duration or ‘ferry cargo – either internally or externally’ up to 2,500 pounds to a range of 110 nautical miles.

The first flight of the aircraft is expected by the end of the year. Before that happens, the Fire-X team plans to conduct preliminary flights of the air vehicle at Fort Worth in a manned configuration to validate its GN&C (Guidance, Navigation and Control) system over the next month and then convert it back to an unmanned system. “After completion of ground testing and engine runs, the air vehicle will be ferried, in an optionally piloted configuration, to the US Army’s Yuma Proving Ground in Arizona for final testing before Fire-X’s first demonstration flight in an unmanned configuration,” said the statement.

It quoted George Spongberg, Northrop Grumman’s Fire-X program manager, as saying, “The Fire-X ‘power-on’ sequence, which validates the integrity of the electrical system, went exactly as planned.” He also added, “It confirmed that the air vehicle’s vehicle management system has been configured properly, and that all of the air vehicle’s new wire harnesses are delivering power at the right levels to all of the major subsystems.” The aircraft’s wire harnesses were produced, tested and installed by Bell Helicopter.

The Xworx team took four months to convert a piloted aircraft into an unmanned or optionally piloted aircraft, by modifying a commercial Bell 407 into the Fire-X vehicle configuration, removing ‘non-mission-essential equipment such as seats and sound insulation’ and installing ‘new wire harnesses and avionics required to control the vehicle in an unmanned configuration’.

But how do you make an unmanned aircraft follow the orders of ground controllers? Earlier this month, fighter aircraft were nearly scrambled after a US Navy MQ-8B Fire Scout wandered into restricted airspace near Washington DC.

“The challenge,” explains Spongberg, “is to duplicate, using hardware and software, the behavior of the air vehicle when it is flown by a human. For example, we’re installing and testing actuators that will move the air vehicle’s flight control surfaces in response to commands from a ground control station the same way they would move in response to commands from a pilot in the cockpit.” His team is also installing and validating the software that will perform the critical GN&C functions for the new system.

The Indian Navy is currently window-shopping for Rotary UAVs, having issued a Request for Information (RFI) last month light of the delays in the conversion of the Chetak helicopter into an unmanned platform. Northrop Grumman’s Fire Scout was also speculated as a contender, besides
EADS’ Orka 1200, Boeing’s Hummingbird and Israel Aerospace Industries’ (IAI) Malat’s NRUAV.