AF Guardian
Encyclopedia
{
The Grumman AF Guardian was the first purpose-built anti-submarine warfare
(ASW) carrier-based aircraft
to enter service with the United States Navy
. It consisted of two airframes, one for detection gear, the other for weapons. The Guardian remained in service until August 1955, when it was replaced by the twin-engine Grumman S-2 Tracker. The Guardian was the largest single-engine piston-powered carrier aircraft ever to see service.
The original design concept for the aircraft that would become the Guardian, the XTB2F of 1944, was to be a twin-engined aircraft with a 3,600 lb (1,633 kg) warload and a range of 3,700 mi (5,950 km). This was considered to be too large for practical use from an Essex class aircraft carrier
, and was canceled in 1945, replaced by a modified Grumman F7F Tigercat, the XTSF-1
.
However, this too was considered impractical, and another alternative, the internally-developed Grumman Model G-70, was selected instead, being given the Navy designation XTB3F. This was designed as mixed-power aircraft, with a Pratt & Whitney Double Wasp radial engine in the nose and a Westinghouse 19XB
turbojet in the tail. This was found to be unsuitable and the jet engine was removed without ever having been used in flight. The XTB3F-1S carried a crew of two seated side-by-side and an armament of two 20 mm cannon
and 4,000 lb (1,814 kg) of bomb
s, torpedo
es and/or rocket
s, and made its first flight on 19 December 1945.
On 24 December 1945, the Navy changed the role of the aircraft from torpedo-bomber to anti-submarine warfare. All the required equipment could not be fitted into a single aircraft, consequently two variants would be produced, one as a "guppy" (hunter) and another as a "scrapper" (killer). The hunter aircraft would not carry any armament, but instead two additional crew members and a ventral radome for APS-20 search "eyes" (radar
) and Electronic Countermeasures
(ECM) "ears", consisting of an APR-98 Countermeasures Receiver and AP-70 Bearing Indicator. This aircraft, the XTB3F-1S, first flew in November 1948. The "killer" deleted the cannon of the torpedo bomber, but retained the bomb bay, added a third crewmember, a searchlight
, and short-range radar, and (as the XTB3F-2S) first flew in January 1949.
Redesignated as AF-2W (TB3F-1S) and AF-2S (TB3F-2S), the Guardian entered fleet service on 27 September 1950 with three aircraft delivered to VS-24,with full service introduction shortly after with VS-25. A total of 193 AF-2S Guardians were built. In 1952, the AF-3S (hunter) was introduced, fitting a magnetic anomaly detector
(MAD) for the detection of submerged submarines; 40 of this variant were built. The last Guardian was delivered to the Navy in March 1953, with a total of 389 built.
The Guardian saw service in the maritime patrol role during the Korean War
, however it proved unpopular with pilots, being underpowered and heavy on the controls; the aircraft suffered from a severely high accident rate. Shortly after the end of the war, it began to be replaced by the Grumman S2F Tracker, the first purpose-built single airframe ASW airplane to serve the U.S. Navy. The last AF retired from active service on 31 August 1955, but it remained in service with the US Naval Air Reserve until 1957.
XTB3F-1
XTB3F-1S
AF-2S
AF-2W
AF-3S
Grumman Model G-90
California in the forest fire-fighting role, the last being retired in 1978.
On 30 March 1954, after encountering engine trouble while on a rescue mission, pilot Lt. John W. Miller with his two crew, Bill Burris and Walter G. Brown ditched an AF Guardian in the water near Santa Cruz Island. A rescue helicopter picked them up that afternoon but the Grumman AF Guardian remains in 60 ft of water to become a living reef and no efforts have been made since to recover the aircraft.
The Grumman AF Guardian was the first purpose-built anti-submarine warfare
Anti-submarine warfare
Anti-submarine warfare is a branch of naval warfare that uses surface warships, aircraft, or other submarines to find, track and deter, damage or destroy enemy submarines....
(ASW) carrier-based aircraft
Carrier-based aircraft
Carrier-based aircraft are military aircraft designed specifically for operations from aircraft carriers. The term is generally applied only to fixed-wing aircraft, as naval helicopters are able to operate from a wider variety of aviation-capable ships. Carrier-based aircraft must be relatively...
to enter service with the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
. It consisted of two airframes, one for detection gear, the other for weapons. The Guardian remained in service until August 1955, when it was replaced by the twin-engine Grumman S-2 Tracker. The Guardian was the largest single-engine piston-powered carrier aircraft ever to see service.
Design and development
Essex class aircraft carrier
The Essex class was a class of aircraft carriers of the United States Navy, which constituted the 20th century's most numerous class of capital ships with 24 vessels built in both "short-hull" and "long-hull" versions. Thirty-two were originally ordered; however as World War II wound down, six were...
, and was canceled in 1945, replaced by a modified Grumman F7F Tigercat, the XTSF-1
Grumman XTSF
|-See also:-External links:* , The Grumman Pages.* , U.S. Military Aircraft and Weapon Designations...
.
However, this too was considered impractical, and another alternative, the internally-developed Grumman Model G-70, was selected instead, being given the Navy designation XTB3F. This was designed as mixed-power aircraft, with a Pratt & Whitney Double Wasp radial engine in the nose and a Westinghouse 19XB
Westinghouse J30
-See also:...
turbojet in the tail. This was found to be unsuitable and the jet engine was removed without ever having been used in flight. The XTB3F-1S carried a crew of two seated side-by-side and an armament of two 20 mm cannon
Cannon
A cannon is any piece of artillery that uses gunpowder or other usually explosive-based propellents to launch a projectile. Cannon vary in caliber, range, mobility, rate of fire, angle of fire, and firepower; different forms of cannon combine and balance these attributes in varying degrees,...
and 4,000 lb (1,814 kg) of bomb
Bomb
A bomb is any of a range of explosive weapons that only rely on the exothermic reaction of an explosive material to provide an extremely sudden and violent release of energy...
s, torpedo
Torpedo
The modern torpedo is a self-propelled missile weapon with an explosive warhead, launched above or below the water surface, propelled underwater towards a target, and designed to detonate either on contact with it or in proximity to it.The term torpedo was originally employed for...
es and/or rocket
Rocket
A rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction...
s, and made its first flight on 19 December 1945.
On 24 December 1945, the Navy changed the role of the aircraft from torpedo-bomber to anti-submarine warfare. All the required equipment could not be fitted into a single aircraft, consequently two variants would be produced, one as a "guppy" (hunter) and another as a "scrapper" (killer). The hunter aircraft would not carry any armament, but instead two additional crew members and a ventral radome for APS-20 search "eyes" (radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
) and Electronic Countermeasures
Electronic countermeasures
An electronic countermeasure is an electrical or electronic device designed to trick or deceive radar, sonar or other detection systems, like infrared or lasers. It may be used both offensively and defensively to deny targeting information to an enemy...
(ECM) "ears", consisting of an APR-98 Countermeasures Receiver and AP-70 Bearing Indicator. This aircraft, the XTB3F-1S, first flew in November 1948. The "killer" deleted the cannon of the torpedo bomber, but retained the bomb bay, added a third crewmember, a searchlight
Searchlight
A searchlight is an apparatus that combines a bright light source with some form of curved reflector or other optics to project a powerful beam of light of approximately parallel rays in a particular direction, usually constructed so that it can be swiveled about.-Military use:The Royal Navy used...
, and short-range radar, and (as the XTB3F-2S) first flew in January 1949.
Operational history
Magnetic anomaly detector
A magnetic anomaly detector is an instrument used to detect minute variations in the Earth's magnetic field. The term refers specifically to magnetometers used by military forces to detect submarines ; the military MAD gear is a descendent of geomagnetic survey instruments used to search for...
(MAD) for the detection of submerged submarines; 40 of this variant were built. The last Guardian was delivered to the Navy in March 1953, with a total of 389 built.
The Guardian saw service in the maritime patrol role during the Korean War
Korean War
The Korean War was a conventional war between South Korea, supported by the United Nations, and North Korea, supported by the People's Republic of China , with military material aid from the Soviet Union...
, however it proved unpopular with pilots, being underpowered and heavy on the controls; the aircraft suffered from a severely high accident rate. Shortly after the end of the war, it began to be replaced by the Grumman S2F Tracker, the first purpose-built single airframe ASW airplane to serve the U.S. Navy. The last AF retired from active service on 31 August 1955, but it remained in service with the US Naval Air Reserve until 1957.
Variants
- Prototypes of two-seat torpedo bomber powered by two 2,300 hp R-2800-46 engines and a Westinghouse turbojet; three built.
XTB3F-1S
- Two modified XTB3F-1 prototypes with turbojet removed and ventral radome , later re-designated as XAF-1.
AF-2S
- Production variant with 2,400 hp R-2800-48 engines, 193 built.
AF-2W
- Hunter variant with search radar in a ventral radome, 153 built.
AF-3S
- Hunter/Killer variant similar to AF-2S with retractable MAD boom, 40 built.
Grumman Model G-90
- Proposed combined AF-2S/-2W version, cancelled.
Operators
- United States NavyUnited States NavyThe United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
- Aero UnionAero UnionFor the Mexico City based cargo Airline see AeroUnionAero Union Corporation is an aircraft operation & maintenance company based in Chico, California, United States...
Survivors and aircraft on display
After disposal by the U.S. Navy five Guardians saw many years service with Aero Union based at ChicoChico
-Given name:* Chico Marx , actor and one of the Marx Brothers* Chico Buarque , Brazilian singer and writer* Chico DeBarge , R&B singer* Chico Ejiro, Nigeria film director* Chico Mendes , Brazilian environmental activist...
California in the forest fire-fighting role, the last being retired in 1978.
- An ex-Aero Union AF-2S, BuNo 123088, civil registration N3143G, is currently dismantled, and in storage in Ocala, FloridaOcala, FloridaOcala is a city in Marion County, Florida. As of 2007, the population recorded by the U.S. Census Bureau was 53,491. It is the county seat of Marion County, and the principal city of the Ocala, Florida Metropolitan Statistical Area, which had an estimated 2007 population of 324,857.-History:Ocala...
. While owned by Aero Union this aircraft was converted into a fire-bomber, but never saw service in that role. It is owned by Aero-Trans Corporation. This is the same aircraft advertised for sale by Aero Union in July 2003. - An ex-Aero Union AF-2S, BuNo 126731, civil registration N9993Z, is currently owned by the Commemorative Air ForceCommemorative Air ForceThe Commemorative Air Force , formerly known as the Confederate Air Force, is a Texas-based non-profit organization dedicated to preserving and showing historical aircraft at airshows primarily throughout the U.S. and Canada...
. The aircraft was restored in 1997, and flew briefly with the CAF as "Navy 126731/SM/10". The aircraft is currently on static display with its wings folded at the CAF's Mesa facility in Mesa, ArizonaMesa, ArizonaAccording to the 2010 Census, the racial composition of Mesa was as follows:* White: 77.1% * Hispanic or Latino : 26.54%* Black or African American: 3.5%* Two or more races: 3.4%* Native American: 2.4%...
. - An AF-2S, BuNo 126759, civil registration N3144G, is in open storage in Tulare, CaliforniaTulare, CaliforniaTulare is a city in Tulare County, California, United States. The population was 59,278 at the 2010 census.Just eight miles south of Visalia, it is part of the Census Bureau's designation of the Visalia Metropolitan Area. The city is named for the currently dry Tulare Lake, once the largest...
. - An ex-Aero Union AF-2S, BuNo 126792, civil registration N9995Z, is currently in the collection of Jimmy Leeward, and located at the Leeward Air Ranch at Ocala, FloridaOcala, FloridaOcala is a city in Marion County, Florida. As of 2007, the population recorded by the U.S. Census Bureau was 53,491. It is the county seat of Marion County, and the principal city of the Ocala, Florida Metropolitan Statistical Area, which had an estimated 2007 population of 324,857.-History:Ocala...
. This aircraft had flown as Tanker #E21 with Aero Union until 1977. It was owned by the EAA Aviation Foundation in Oshkosh, WisconsinOshkosh, WisconsinAs of the census of 2000, there were 62,916 people, 24,082 households, and 13,654 families residing in the city. The population density was 2,662.2 people per square mile . There were 25,420 housing units at an average density of 1,075.6 per square mile...
from 1984 until 1986, when it was acquired by Jimmy Leeward. It currently flies as "Navy 126792". - An ex-Aero Union AF-2S, BuNo 129233, civil registration N9994Z, is preserved at the Pima Air Museum, Tucson, Arizona. The aircraft is displayed in incorrect Aero Union fire-fighting markings as "N9995Z Tanker E21", the aircraft that is now at the Leeward Air Ranch (see above).
- Another ex-Aero Union AF-2S, BuNo 123100, civil registration N3144G, is on display at the National Museum of Naval AviationNational Museum of Naval AviationThe National Museum of Naval Aviation is a military and aerospace museum located at Naval Air Station Pensacola, Florida. The museum opened in 1962....
in Pensacola, FloridaPensacola, FloridaPensacola is the westernmost city in the Florida Panhandle and the county seat of Escambia County, Florida, United States of America. As of the 2000 census, the city had a total population of 56,255 and as of 2009, the estimated population was 53,752...
. It was the seventh AF-2S produced. The aircraft was operated as a firefighter until 1978. It was acquired by the museum in 1980. It is displayed in the colors of its first Navy assignment, though still carries the non-historical number "30" on the cowling, for many years the aircraft's call-sign while operating as a fire fighting aircraft;
On 30 March 1954, after encountering engine trouble while on a rescue mission, pilot Lt. John W. Miller with his two crew, Bill Burris and Walter G. Brown ditched an AF Guardian in the water near Santa Cruz Island. A rescue helicopter picked them up that afternoon but the Grumman AF Guardian remains in 60 ft of water to become a living reef and no efforts have been made since to recover the aircraft.