Born to hunt Soviet submarines, Grumman’s S-2 Tracker or Stoof has been adapted to do several jobs over the years. From the C-1A Trader COD to the Stoof with a Roof E-1 Tracer AEW platform and the ubiquitous US-2 utility transport, the aircraft has done everything asked of it. Nowadays a few Stoofs and CODs fly in civilian hands as warbirds. Over the years Trackers were also adapted for use as aerial firefighting tankers. Today, the California Department of Forestry & Fire Protection or Cal Fire operates 23 turbine-powered S-2T aerial firefighting, or fire-hunting, tankers.During and since the 1970s Cal Fire and others operated Firecats, which were Trackers powered by the original Wright R-1820-82WA radial engines but modified with a raised cabin floor to fit a retardant tank in the bomb bay. Today’s S-2Ts are relatives of those first Tracker Tankers. All Tracker conversions removed the anti-submarine warfare (ASW) mission equipment and faired over the ventral radar housing (radome) and the tail-mounted magnetic anomaly detector (MAD) sensor and extending boom located under the rudder aft. The plumbing for hot loading the retardant tank is connects there now. These modifications removed about 3,300 pounds from the Tracker. There are no more radial engine-powered Trackers in firefighting service.
Built by Grumman Aerospace at their Bethpage plant on New York’s Long Island at least one generation ago, the S-2Ts were mostly S-2E or S-2G variants while operated by the US Navy. Cal Fire acquired the S-2 airframes in 1996 and Marsh Aviation in Arizona converted them to aerial firefighting tankers. The Turbine Trackers are faster than stock S-2s but their Garrett TPE331-14GR turbine engines only put out about 100 more horsepower each than the original Wright R-1820-82WA radial engines did. The S-2Ts are also usually crewed by a single pilot and can haul up to 1,200 gallons of retardant or water.