Grumman AF

Grumman AF Guardian
Grumman AF-2S from the US Museum of Naval Aviation
Type:	Anti-submarine aircraft
Design country:	United States
Manufacturer:	Grumman Aircraft Engineering Corporation
First flight:	December 19, 1945
Commissioning:	October 1950
Production time:	1950 to 1953
Number of pieces:	389

An AF-2S lands on the USS Badoeng Strait in 1954

AF-2W and AF-2S of the VS-25 anti-submarine squadron

AF-2S with the bomb bay open

3-sided tear of an AF-2S

The Grumman AF Guardian was a United States Navy anti-submarine aircraft (ASW) . To date, the Guardian is the largest single-engine piston -engined aircraft ever to be mass-produced .

construction

The AF Guardian was originally planned as a torpedo bomber with jet and propeller engines in order to be able to evade attacks more quickly. The jet engine caused big problems, however, and it was never used in flight. The machine was to be used together with an unarmed version with search radar as a so-called hunter / killer team. These hunter / killer teams consisted of a machine with bombs or torpedoes and a machine with search radar.

history

The AF was originally intended to replace the TBF Avenger in the US Navy . It emerged from the three prototypes XTB3F (Grumman G-70), which the Bureau of Aeronautics had commissioned from Grumman in 1946 . The XTB3F-1 Guardian first flew on December 19, 1945 . Five days after the first flight, the Navy came to the conclusion that they actually didn't need a new torpedo bomber. The program was activated again in 1947 to implement anti-submarine defense by a hunter / killer team. One aircraft used radar to search for submarines (the "hunter" = fighter), while a second aircraft was used to attack the submarines (the "killer" = destroyer). In May 1948 the Navy ordered 30 machines and in October 1948 the original third prototype XTB3F-1S flew in which the jet engine was replaced by additional avionics and fuel. The aircraft AF-2W and AF-2S, modified as Hunter / Killer , flew for the first time in November 1948. In February 1949, the Patuxent River Naval Air Test Center checked the Guardian for serviceability and shortly afterwards the first series orders for the two AF versions were received -2S and AF-2W. The Guardian's first squadron flew the VS-25 at North Island Naval Air Base on October 18, 1950. The Guardian's career did not last long, however. Already on August 31, 1955 it was replaced by the S-2 Tracker , which combined the hunter / killer tasks in one aircraft. But she flew some combat missions in Korea .

Versions

XTB3F-1

Prototype of a torpedo bomber, two built.

XTB3F-1S

Prototype with large radar under the fuselage (conversion from XTB3F).

AF-2S

This version was the gun bearer of the Hunter / Killer team. A weapon load of up to 1814 kg could be carried internally. 6 HVAR rockets or 113 kg depth charges could be carried on the carrier under the wings. A radar vessel AN / APS-31 hung under the right wing and an AN / AVQ-2 high-performance searchlight under the right wing. In addition, this version could still carry sonar buoys. 193 aircraft of this version were built.

AF-2W

unarmed version with AN / APS-20 radar, 153 aircraft built.

AF-3S

improved version of the AF-2S. They carried additional ASW equipment with them, e.g. B. a MAD boom, 40 built.

production

Acceptance of Grumman AF by the US Navy:

version	1949	1950	1951	1952	1953	TOTAL
AF-2S	1	25th	58	110	14th	208
AF-2W	1	26th	50	60	16	153
AF-3S					25th	25th
TOTAL	2	51	108	170	55	386

Technical specifications

Grumman AF-2S Guardian

Type:	2-seat submarine fighter
Engine:	an 18-cylinder double radial engine Pratt & Whitney R-2800 -48W with 1780 kW (2420 hp)
Span:	18.49 m
Length:	13.21 m
Height:	4.93 m
Wing area:	52.02 m²
Top speed:	510 km / h at an altitude of 4875 m
Service ceiling:	9905 m
Range:	2414 km
Empty mass:	6613 kg
Max. Takeoff mass:	11567 kg
Armament:	one 907 kg torpedo or 2 907 kg bombs or 2 726 kg depth charges

Web links

Commons : Grumman AF Guardian  - collection of images, videos and audio files

Individual evidence

1. ^ Scott Johnson: Grumman's Goliath , Airplane Monthly, July 1979, p. 367
2. ↑ FliegerRevue March 2012, pp. 52-55, Grumman AF-2 Guardian
3. ↑ Statistical Digest of the USAF 1949, p. 164 ff .; 1951, p. 153 ff .; 1952, p. 153 ff .; 1953, p. 185