Introduced in 1952, the Grumman S-2 Tracker was a conventional design, single airframe with twin engines, a high wing and tricycle undercarriage, originally built for the U.S. Navy for carrier-based anti-submarine warfare (ASW). The S-2 was also exported to navies around the world.

In the 1970’s CAL FIRE, which has long been the premier firefighting aviation program with the largest fleet of aerial firefighting equipment in the world, converted and completely reconditioned the S-2 Tracker into a fire fighting airtanker, fitting them with modern, powerful turboprop engines, making the aircraft faster, safer, and more maneuverable, utilizing the S-2 for fast initial attack delivery of fire retardant on wildland fires.