The Fairchild Republic A-10 Thunderbolt II, better known as the Warthog, is a famously capable close-air support platform. Boasting a low stall speed, durable airframe, and ability to operate from short and/or unpaved runways, the Warthog is the only production-built aircraft flown by the U.S. Air Force that was designed specifically for the CAS mission. Although it entered service in 1977 with the intent to rip apart Soviet armor coming across the Fulda Gap in Germany, the A-10 cemented its legacy in the Middle East where it flew 8,100 sorties during Desert Storm and became a favorite of ground troops during the Global War on Terror. In 2014, when the Air Force announced its intention to retire the Warthog, one company saw new life for the aircraft as a firefighter.
On September 10, 2014, USA Firefighting Air Corps presented a proposal to the Colorado State Legislature’s Wildfire Matters Review Committee. The proposal called for USAFAC to collaborate with states (including Colorado) to invest in the development of an A-10-based airtanker while the states explore the acquisition of retired Warthogs from the Air Force. USAFAC also called for the development of long-term public-private partnership agreements to sustain the fire aviation program that they aimed to build on the A-10 “Firehog.”
First, the A-10 would be demilitarized, losing its famous GAU-8/A Avenger 30mm cannon, weapons pylons not used for external fuel tanks, and other military-specific equipment like the chaff and flare launcher. The fuel tanks would be rearranged to allow for the fitting of liquid tanks and a storage tank for concentrated fire retardant. Notably, the iconic protrusion of the gun from the front of the Warthog would be replaced with a refilling probe that would allow for inflight refilling.
“The airtanker can fly from the tanker base to a fire, drop its original liquid load, refill from an orbiting aircraft and drop a second time in 15 minutes, refill inflight and drop a third time in another 15 minutes, and then return to the tanker base for fuel and liquid in a total of 85 minutes,” USAFAC said in the proposal. “In other words, our new airtanker can deliver approximately 4500 gallons of liquid and be reloaded for takeoff from base in approximately the time it currently takes a common heavy airtanker to deliver 2500 gallons of liquid and reload.”
Certain military aspects of the A-10 could give it an advantage as a firefighter. USAFAC notes that an infrared vision system fitted to the A-10 would allow it to detect the IR radiation of a fire before smoke is visible, as well as detect fires in reduced visibility. Similarly, the A-10 is an all-weather aircraft with flight systems that allow it to fly in most weather conditions, day and night. The hazard of bird strikes is addressed by USAFAC with the addition of deflectors over the engine intakes. While the proposal uses the A-10 as an example platform, USAFAC highlights that different airframes could be used to achieve the same capabilities.
Ultimately, the proposal for a “Firehog” airtanker was not accepted. “[USAFAC’s] proposal uses arguments mentioned by other companies that have little to no experience in aerial firefighting — they emphasize electronics and technology that they claim will make their concept much better than existing air tankers,” Bill Gabbert wrote in Fire Aviation. “While there is room for improvement in constant flow retardant delivery systems, the A-10’s bomb sights and infrared sensors are not game changers.” Although the A-10 did not become a firefighter, the AH-1 Cobra was successfully converted to fly aerial reconnaissance and supervision missions for the USDA’s Fire Service as the Firewatch Cobra.