The Grumman S-2 Tracker was the first purpose-built, single airframe anti-submarine warfare (ASW) aircraft to enter service with the U.S. Navy. The Tracker was intended as a replacement for the Grumman AF Guardian, which was the first purpose-built aircraft system for ASW. This system used two aircraft, one with the detection gear, and the other with the weapon systems. The Tracker combined both functions in one aircraft.
Designed and initially built by Grumman, the Tracker was of conventional design, with twin engines, a high wing and tricycle undercarriage.
The first flight was conducted on 4 December 1952, and production aircraft entered service with VS-26, in February 1954.
Grumman produced 1,185 Trackers. Up to one hundred aircraft carrying the CS2F designation were manufactured in Canada under license by de Havilland Canada. U.S.-built versions of the Tracker were sold to various nations, including Australia, Japan, Turkey and Taiwan.
In general terms, the Tracker was designed to carry two lightweight torpedoes or one nuclear depth charge. There were also six underwing hard points for rocket pods and conventional depth charges or up to four additional torpedoes.
Early model Trackers had an Electronic Surveillance Measures (ESM) pod mounted dorsally just aft of the front seat overhead hatches and were also fitted with a smoke particle detector or 'sniffer'. A 70 million candlepower searchlight was mounted on the starboard wing, and smoke dispensers were mounted on the port ventral surface of the nacelles in groups of three each. Later, the S-2,s had the sniffer removed and had the ESM antennae moved to four rounded extensions on the wingtips.
The engine nacelles carried JEZEBEL sonobouys in the rear, 16 in early models, and 32 in the S-2E/G that Australia used.
In addition to USA and Australia, Argentina, Brazil, Canada, Italy, Japan, Netherlands, Peru, South Korea, Taiwan (Republic of China), Thailand, Turkey, Uruguay, and Venezuela also used these aircraft. Argentina and Brazil are the last countries still using the Tracker.
Many retired Trackers were sold to private owners for fire-fighting duties in Canada, France, Netherlands and the United States. Some were rebuilt with turboprop engines.
Introduced in 1952 the Tracker saw service in the USN until the last Navy S-2 was withdrawn from service on 29 August 1976. Trackers continued to provide excellent service with the naval forces of other countries for years after the U.S. discontinued them. For example, the Royal Australian Navy continued to use Trackers as front line ASW assets until the mid-1980’s.
The Royal Australian Navy ordered 32 aircraft, which were delivered between 1966 and 1977, allowing the FAA to operate two Squadrons of S-2E and S-2G variants, primarily based at HMAS Albatross, between 1967 and 1984. These were 816 front line squadron, which flew from HMAS Melbourne, as part of the 21st Carrier Air Group whenever that ship was deployed; and 851 training squadron.
During approximately 17 years of operation of the Tracker, the RAN lost only one S-2 during aircraft operations, this due to an accident at sea on 10 February 1975. However, on 4 December 1976, a deliberately lit fire in a hangar at Nowra destroyed or badly damaged a large proportion of the RAN's complement of Trackers. These were subsequently replaced with ex-USN aircraft. The replacement aircraft were all S-2Gs. This saw the introduction of AQA-7 acoustic gear into RAN service, and all the remaining RAN operational Trackers were subsequently modified to this standard.
These aircraft had a crew of four, consisting of two pilots and two detection systems operators; they were 43 feet 6 in (13.26 m) long, 17 feet 6 in (5.33 m) high and had a Wingspan of 72 feet 7 in (22.12 m), giving them a wing area of 485 foot² (45.06 m²). Their power plant consisted of two Wright R-1820-82WA radial engines, delivering 1,525 hp (1,137 kW) each.
They had a maximum speed of 265 mph at sea level, and could cruise at 150 mph (240 km/h) for 9 hours, or for 1,350 miles (2,170 km). their service ceiling was 21,000 feet.
The Australian Grumman Trackers could carry a payload of 4,800 lb (2,200 kg) in the internal bomb bay and on their six under-wing hardpoints. This allowed them to carry two anti submarine torpedoes or 4 depth charges in its bomb bay, plus 6 underwing racks for rockets, torpedoes or 250 lb bombs, plus their active and passive Sonobuoys.
Today, Australian Trackers are on display at the Queensland Air Museum, at the Fleet Air Arm Museum, at HMAS Albatross, and at the National Vietnam Veterans Museum at Phillip Island in Victoria.