Vertiflite May/June 2021

An Air Force HH-60G exits a dust cloud. (US Air Force)

Through Pave Hawk Eyes

T he US Air Force’s HH-60G Pave Hawk program office at Robins Air Force Base, Georgia, is managing efforts to field a degraded visual environment system (DVES) on the retiring rescue helicopter. The new safety system integrates a new light detection and ranging (lidar) sensor with existing infrared visionics to give crews better situational awareness taking off, hovering and landing in dusty brownout or snow-blind whiteout. It also aims to help pilots avoid wires, towers, trees and terrain en route in clear day or night flight. The program office expects DVES flight tests this spring and plans to outfit 18 Pave Hawks beginning in April 2022. Options to equip another 61 helicopters may stretch installations through April 2023. The Air Force began retiring HH-60Gs in March 2021, but Pave Hawks are expected to be in service through 2029, largely in National Guard and Reserve units. The Air Force is taking delivery of 108 new HH-60W Jolly Green Giant IIs with an eye to some future DVE upgrade, but has yet to assess integration on the replacement combat rescue helicopter with fully integrated avionics architecture and digital automatic flight control system. Sensor Synergy Four HH-60G crewmembers and three Guardian Angel pararescuemen died in March 2018 when their low-flying Pave Hawk hit a steel cable in Iraq. The accident report concluded that the low illumination conditions made standard AN/AVS-9G night By Frank Colucci The Air Force integrates a multi-sensor degraded visual environment system (DVES) on its legacy rescue helicopter.

vision goggles (NVGs) insufficient to detect cables. The multi- sensor DVES overlays lidar or forward-looking infrared (FLIR) imagery with digital terrain elevation data on existing cockpit displays to show pilots real-time obstacles, reference points and landing zones. The two-axis, fast-scanning lidar generates a very high-resolution, near real-time three-dimensional picture of terrain, obstacles and traffic in light to moderate DVE. The AN/ AAQ-29A FLIR, long in the Pave Hawk fleet, is a 3- to 5-micron navigation sensor. Pave Hawk pilots and co-pilots will select from three DVES modes independently to post symbology over lidar imagery, FLIR imagery or a flat black background. The DVES is based on the degraded visual environment pilotage system (DVEPS) developed for Army Special Operations MH-60M Black Hawks and MH-47G Chinooks. The Pave Hawk system uses the same Sierra Nevada Corp. (SNC) lidar and a similar image processor in a configuration different from the DVEPS synthetic visual avionics backbone. SNC in Sparks, Nevada, is the DVES prime contractor and Leonardo DRS in Beavercreek, Ohio, the designated subcontractor to integrate Group A aircraft provisions. Areté in Northridge, California, manufactures the lidar sensor, while other subcontractors provide pieces of the Group B functional kit. The Georgia Tech Research Institute advises the HH-60G program office on the DVES program. See Through and Cue DVES operational requirements were developed by the US Air Force’s Air Combat Command and Pave Hawk system program office with input from pilots, aircrew, maintainers, engineers and subject matter experts. The Air Force Research Laboratory (AFRL) in Dayton, Ohio, led the precursor Three-Dimensional Landing Zone (3D-LZ) Joint Capability Technology Demonstration (JCTD) to help with helicopter approach and landing in degraded visual

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