Honeywell engineers are now developing a software upgrade for the AgustaWestland AW139 medium twin that optimizes the helicopter’s Primus Epic avionics system for the rigors of search-and-rescue operations.
The Phase 5 update for the AW139 cockpit recently underwent flight testing at Honeywell in Phoenix. It adds automated search patterns, automatic radar altitude hover, a “fly-up” safety limiter and other autopilot functions intended to ease workload and enhance safety for AW139 crews performing SAR missions in demanding environments.
The radar altitude hover function, for example, will allow the AW139 to hover automatically in rough seas with wave heights up to 20 feet, while the safety limiter will automatically climb away from bigger waves. The Phase 5 upgrade will also add a winchman trim feature that lets the hoist operator maneuver the helicopter from the cabin. These added features are sure to be welcomed by crews flying ocean rescue missions at night in poor weather.
A Phase 4 software upgrade for the AW139’s Primus Epic cockpit certified in March also added a host of advanced capabilities, including a special display for controlling auto hover functions, four-axis autopilot and flight director, VGP (Vnav glidepath) and 7.5-degree approach capabilities, FMS heliport approaches and other features. Future enhancements to the AW139’s Epic suite are expected to include WAAS/LPV approach capability, low RNP approaches, ADS-B, charts and maps display and an optional XM weather receiver.
The functionality in the AW139 FMS is identical to that of the flight management systems used in Gulfstreams flying with the PlaneView cockpit. This caused some confusion during a demo last month in Honeywell’s corporate AW139 from Morristown Municipal Airport in New Jersey when an error inputting the fuel-flow values into the FMS rendered the GPS approach capabilities useless. The problem wasn’t discovered until well into the demo flight while attempting to execute a VGP approach. Because the proper performance data hadn’t been entered into the FMS before takeoff, the system refused to accept the VGP approach. Honeywell senior technical manager James Nicholls said the error was corrected on the next flight and VGP approaches were flown without further problem.
A feature recently added to the AW139’s automatic flight controls repertoire was an approach to an auto hover, accomplished by pressing the HOV button on the cyclic control. The hover display allows the pilot to see a top-down presentation of his location and position a green dot over the spot where he would like the helicopter to hover. Height can also be controlled and adjusted at any time. The AW139’s four-axis autopilot with full auto-hover capability gives the crew far greater ability to operate low over water at night, particularly during winch operations, Nicholls said.
The AW139’s cockpit includes four 8- by 10-inch LCD flight displays, dual FMS, helicopter EGPWS, TCAS I, Primus 660/701 weather radar and HUMS (health and usage monitoring) in addition to a suite of nav and com radios. Nicholls said Honeywell will incrementally upgrade the AW139 flight deck based on AgustaWestland’s schedule. With Phase 5 flight testing finished, Honeywell expects certification soon. Additional advanced features will take somewhat longer. Under study is a version of Honeywell’s synthetic-vision system for helicopters, the view from which would fill the entire PFD.