The U.S. Air Force will equip between 150 and 200 Fairchild-Republic A-10C Thunderbolt II combat aircraft with 3D-audio systems developed by Terma A/S, a Lystrup, Denmark-based aerospace and defense firm. The Terma 3D-audio system will enhance pilot situational awareness by supplementing the A-10C cockpit control panel visual warning system with audible directional signals from within the pilot’s helmet. The natural or “spatially separated” audio signals will be similar to what a human would hear when not wearing a conventional headset.
Terma’s 3D-audio system is already employed by the Royal Danish Air Force on its Lockheed Martin F-16 Fighting Falcon fourth-generation multirole fighters and can alert pilots to a variety of imminent threats by collecting data from aircraft missile warning systems, radar warner receivers, laser warner systems, and small arms detection systems by sending processed audio to a stereo headset.
Terma is the first company in the world to develop and field 3D-audio technology to reduce pilot workload and enhance situational awareness. Initial studies in a cockpit environment comparison test showed that pilots perceived the direction of an approaching missile threat 1.5 seconds faster by using 3D-audio cuing compared to only using a cockpit panel-mounted display.
The system – which is accurate to within 15 degrees of source signal azimuth and elevation – can also provide terrain obstruction warnings and link display and auditory directional cues together.
In December 2017, the U.S. Air Force issued a request for information for a commercial off-the-shelf (COTS) 3D-audio system in order to improve the spatial, battlespace, and situational awareness of its A-10C pilots. On November 5, 2018, Terma was awarded a sole-source Indefinite Delivery/Indefinite Quantity (IDIQ) contract to deliver the system.
The A-10, originally developed by Fairchild Republic to fill close air support, forward air control, and ground attack roles, is now supported by Northrop Grumman. The aircraft’s low-speed maneuverability, durability, system redundancy, and sizable munitions loadout resulted in it gaining notoriety as a hard-hitting “tank buster” during the Gulf War.
With airframe production ending in 1984, the A-10 is an aging aircraft – current airframes range from 35 to 40 years old. However, the A-10’s effectiveness has resulted in many politically contentious service life extensions and upgrades.
The latest A-10C designation denotes aircraft that have received “Precision Engagement” upgrades to the aircraft’s fire control system, electronic countermeasures, and targeting. More recent modifications include the addition of multifunction displays, high-speed satellite communication links, and increased external fuel tanks. In November 2011, the U.S. Air Force began “re-winging” or replacing wings on existing airframes as part of the A-10’s service life extension program (SLEP).
As of February 2016, analysts estimate modernized A-10C aircraft could operate to 2040 or beyond. With approximately 350 A-10 aircraft split between active U.S. Air Force, Air Force Reserve, and Air National Guard fleets, Terma’s IDIQ contract may increase from original delivery numbers of 150 to 200 3D-audio systems.