Developments in submarine technology following end of World War II led the US Navy to carry out a reappraisal of its carrier-based airborne anti-submarine capability. It approached Grumman to design a compact aircraft able to combine the then separate roles of submarine hunter and submarine killer into a single platform. Grumman responded with the radial-engine G-89, which the Navy went on to acquire in large numbers, and christened the Tracker. Re-engineered versions of the G-89 were also purchased to provide an airborne early warning capability for the carrier strike force, and for the vital, but unsung, role of taking passengers, stores and mail to and from deployed aircraft carriers.
Although the G-89 family was retired by the US Navy in the late-1980s, its service life is only now coming to an end. Following the retirement of Taiwan’s fleet of S-2Ts on 1 Dec 17, just one aircraft remains in active military service (in Argentina). A small number of Trackers remain active on the warbird circuit.
First flight: 4 Dec 52 (XS2F-1 129137)
Production: 1,361 at Bethpage, NY (made up of 1,186 Trackers, 87 Traders and 88 Tracers) and 99 at Downsview, ON (all Trackers).
First delivery: Feb 54, to the US Navy
Last delivery: 5 Oct 67, to the Royal Australian Navy (N12-153607 and N12-153608, c/n 351C and 352C respectively)
Principal variants: G-89/XS2F-1 – prototype, powered by Wright R-1820-76WA radials (2 built);
YS2F-1 – developmental batch, redesignated YS-2A in 1962 (15 built);
S2F-1 – initial production version, powered by uprated R-1820-82WA radials, redesignated S-2A (740 built, first flight 7 Jul 53);
CS2F-1 – S2F-1 optimised for Canada, featuring some Canadian systems (42 built at Downsview, ON; first flight 31 May 56, c/n DHC-02, 1503)
S2F-2 – improved version with lengthened fuselage, enlarged weapons bay and enlarged tail surfaces, redesignated S-2C (77 built, first flight 12 Jul 54);
CS2F-2 – improved version of the CS2F-1 featuring Canadian systems but retaining the fuselage dimensions of the CS2F-1 (57 built at Downsview, ON; first flight 9 Oct 58, c/n DHC-43, 1544);
G-121/S2F-3 – version with further improvements, including enlarged forward fuselage, increased wing-span and additional fuel capacity, redesignated S-2D (100 built, first flight 20 May 59);
S2F-3S – final production version, equipped with passive and active sonar gear from S2F-1S (see conversions), redesignated S-2E (252 built);
G-96/TF-1 – version with weapons systems deleted and redesigned fuselage for use as carrier on-board delivery platform, redesignated C-1A (87 built, of which four completed as G-125/TF-1Q (later EC-1A) for electronic warfare; first flight 19 Jan 55)
G-117/WF-2 – version optimised for airborne early warning, featuring AN/APS-82 search radar in an almost comically large radome mounted over the fuselage, and modified tail section, redesignated E-1B (88 built, first flight 18 Feb 56, by a TF-1 modified as an aerodynamic test platform under the designation WF-1).
Conversions: S2F-1T/TS-2A – 207 S2F-1s modified for training (S2F-1T designation also used for conversions undertaken in the 1970s for use in aerial firefighting on behalf of the California Department of Forestry); US-2A – 51 S-2As modified for use as target tugs; S2F-1S/S-2B – unknown number of S2F-1s modified with the addition of passive and active sonar gear, some being further modified as S2F-1S1/S-2F; US-2B – 66 S-2As and most surviving S-2Bs converted as utility transports;S-2 S2F-2U/US-2C – 48 S2F-2 modified for use in utility roles; S-2G – 50 S-2Es modified from 1972 with improved mission equipment; CS2F-3 – 45 CS-2F-2s upgraded with revised electronics equipment and sensors from 1964 (survivors redesignated CP-121 in 1968). Firecat – version developed by Conair of Abbotsford, BC, featuring a 3,296-litre retardant tank fitted in the weapons bay (32 conversions, first flight in 1978, c/n DHC-36, C-GHQZ); these were preceded by small number of similar conversions carried out by Field Aviation at Calgary, AB and De Havilland Canada at Downsview, ON.
Turbine conversions: Turbo Tracker – conversion engineered by Marsh Aviation of Mesa, AZ, based on the Garrett TPE-331-14GR turboprop (25 conversions completed, mostly from S-2Es, of which 22 were supplied to the California Department of Forestry as S2F-3AT although some were completed from kits; first flight 21 Nov 86, c/n 522, N426DF). Turbo Firecat – Conair-engineered conversion based on the Firecat, developed for France’s Sécurité Civile and featuring the Pratt & Whitney PT6A and enlarged retardant tank (13 conversions, including 9 from Firecats; first flight 7 Aug 88). S-2T – conversion by Grumman for Taiwan using the Garrett TPE-331-15AW and modern avionics (2 converted by Grumman and 25 of a planned 27 completed by AIDC in Taiwan from kits; first flight Jul 88). S-2UP – version developed by Bedek using engine conversion kits supplied by Marsh Aviation and Israeli avionics systems; sold only to Argentina (1 converted in Israel and 3 of a planned 5 converted by the Argentine Navy at Bahía Blanca). Turbo Tracker – version developed by IMP of Halifax, NS, based on the PT-6A-67CF (2 conversions; first flight Sep 88, c/n DHC-84, C-GTRT). The second IMP conversion was the first of a planned 12 for Brazil under the designation P-16H, but the project was cancelled. A more recent attempt by Brazil to obtain Turbo Trackers, from Marsh Aviation, also failed.