Martin B-57 Canberra

The Martin B-57 Canberra is a United States-built, twin jet engine tactical bomber and reconnaissance aircraft that entered service with the United States Air Force (USAF) in 1953. The B-57 was a licence-built version of the English Electric Canberra; the Glenn L. Martin Company later modified the design to produce several unique variants.

The Canberra was the first U.S. jet bomber to drop bombs during combat.^[4] Its retirement in 1983 ended the era of the tactical bomber that had its beginning with the World War I De Havilland DH-4. The two remaining flightworthy WB-57Fs are technically assigned to the NASA Johnson Space Center, next to Ellington Field in Houston, as high-altitude scientific research aircraft,^[1] but are also used for testing and communications in the U.S. and Afghanistan.^[5]

Development

At the outbreak of the Korean War in 1950, the USAF found itself in dire need of an all-weather interdiction aircraft. The piston-engined Douglas A-26 Invaders were limited to fair weather operations and were in short supply. On 16 September 1950, the USAF issued a request for a jet-powered bomber with a top speed of 630 mph (1,020 km/h), ceiling of 40,000 feet (12,190 m), and range of 1,150 miles (1,850 km). Full all-weather capability and secondary reconnaissance role had to be included in the design. To expedite the process, only projects based on existing aircraft were considered. The contenders included the Martin XB-51, and the North American B-45 Tornado and AJ Savage.^{[citation needed]}

Unusually, the service considered foreign aircraft, including the Canadian Avro Canada CF-100 Canuck and the new British English Electric Canberra, which had not yet officially entered service with the Royal Air Force (RAF). The AJ and B-45 were quickly dismissed, because their outdated designs had limited growth potential. The CF-100, an all-weather interceptor, was too small and lacked sufficient range. The XB-51, while very promising and much faster, had limited maneuverability, a small weapons bay and limited range and endurance.

On 21 February 1951, a British Canberra B.2 flown by Roland Beamont became the first jet to make a nonstop unrefueled flight across the Atlantic Ocean, arriving in the United States for USAF evaluation. In a 26 February flyoff against the XB-51, the Canberra emerged a clear winner.^{[citation needed]} It was officially taken up by the USAF on 25 May 1951.

However, because its production lines were working at full capacity to meet the Royal Air Force orders, English Electric was unable to produce additional aircraft quickly enough for USAF requirements, and on 3 April 1951,^{[citation needed]} Martin was granted a license to build Canberras, designated B-57 (Martin Model 272) in the United States. To expedite production, the first B-57As were largely identical to the Canberra B.2, with the exception of more powerful Armstrong Siddeley Sapphire engines of 7,200 lbf (32 kN) of thrust instead of Rolls-Royce Avons, also license-built in the United States as Wright J65s. In addition, canopy and fuselage windows were slightly revised, the crew was reduced from three to two, wingtip fuel tanks were added, engine nacelles were modified with additional cooling scoops, and the conventional "clamshell" bomb bay doors were replaced with a low-drag rotating door originally designed for the XB-51.^[6]

The first production aircraft flew on 20 July 1953, and was accepted by the USAF a month later on 20 August. During the production run from 1953 to 1957, a total of 403 B-57s were built.

Operational history

The B-57A was not considered combat-ready by the USAF and the aircraft were used solely for testing and development. One of the aircraft was given to the National Oceanic and Atmospheric Administration (NOAA) which fitted it with a new nose radome and used it to track hurricanes. The aircraft was placed into limited production. Particularly contentious were the cockpit arrangement and the lack of guns, the Canberra having been designed as a high-speed, high altitude bomber rather than for close air support. The definitive B-57B introduced a new tandem cockpit with a bubble canopy, the engines were now started with a pyrotechnic cartridge, the airbrakes were moved from the wings to the sides of the fuselage for increased effectiveness, the controls were now boosted, four hardpoints were fitted under the wings, and the aircraft was given gun armament in the form of eight 0.50 in (12.7 mm) Browning machine guns in the wings, later replaced by four 20 mm M39 cannons. The first B-57B flew on 18 June 1954. The aircraft initially suffered from the same engine malfunctions as the RB-57As and several were lost in high-speed low-level operations due to a faulty tailplane actuator which caused the aircraft to dive into the ground. The USAF considered the B-57B inadequate for the night intruder role and Martin put all aircraft through an extensive avionics upgrade. Regardless, by the end of 1957, the USAF tactical squadrons were being re-equipped with supersonic North American F-100 Super Sabres. The complete retirement was delayed, however, by the start of the Vietnam War.

Reconnaissance and Electronic warfare B-57s

See also: 7407th Support Squadron, Martin RB-57D Canberra, Martin RB-57F Canberra, Martin WB-57F Canberra

While the USAF found the B-57A lacking, the photo reconnaissance RB-57A saw some operational use. First flying in October 1953, RB-57As fully equipped the 363rd Tactical Reconnaissance Wing at Shaw Air Force Base by July 1954. The aircraft were also deployed with USAF squadrons in Germany, France, and Japan. However, operational readiness was poor and the aircraft suffered from significant production delays because of engine problems. Wright had subcontracted production of J65 engines to Buick, which resulted in slow deliveries and a tendency for engine oil to enter the bleed air system, filling the cockpit with smoke. The problems were ameliorated when Wright took over engine production in 1954. RB-57As also suffered from a high accident rate caused in part by poor single-engine handling. This resulted in the entire fleet spending much of 1955 on the ground. By 1958, all RB-57A craft were replaced in active service by the Douglas RB-66B and McDonnell RF-101A. Air National Guard units extensively used the RB-57A for photographic surveys of the United States until 1971.

A number of modified RB-57As were used by the 7499th Support Group at Wiesbaden AB, West Germany in Operation "Heart Throb" reconnaissance missions over Europe.^[7] Ten aircraft were pulled off Martin's production line and modifications were performed in August 1955 by the Wright Air Development Center and by Martin. All equipment not absolutely essential for the daytime photography role was eliminated. The bomb bay door was removed and the area was skinned over. The seat for the system operator/navigator was removed, and an optical viewfinder was installed in the nose so that the pilot could perform all the reconnaissance duties without the assistance of the navigator. The clear plexiglass nose cone was replaced by an opaque fiberglass cone, but with a small optical glass window cut for the viewfinder. The plane's J65-BW-5s were replaced by higher-thrust J65-W-7s. The aircraft was referred to as RB-57A-1. The weight reduction program shaved 5665 pounds off the weight of the RB-57A, and the ceiling was increased by 5000 feet.^[8]

Two RB-57A-1s were used by the Republic of China Air Force for reconnaissance missions over China; one was shot down by a Chinese Mikoyan-Gurevich MiG-17 on 18 February 1958 and the pilot killed. In 1959, two RB-57Ds were delivered to replace the A-types; one of them was shot down over China by a SA-2 Guideline missile, marking the very first successful operational engagement of surface-to-air missiles. Two other RB-57As were used by the Federal Aviation Administration to plan high-altitude airways for the upcoming jet passenger aircraft.

Starting in 1959, Martin began to modify retired RB-57As with electronic countermeasures (ECM) equipment in the bomb bay. Redesignated EB-57A, these aircraft were deployed with Defense Systems Evaluation Squadrons which played the role of aggressors to train the friendly air defense units in the art of electronic warfare. Subsequent bomber variants were also modified to fulfill this role. Although initially conducted by active duty Air Force units, the EB-57 mission eventually migrated to selected units of the Air National Guard.^[9][10][11] The ANG's EB-57s were replaced, in the 1980s, by the USAF's more advanced General Dynamics/Grumman EF-111A Raven operated by the active-duty USAF.

Strategic Air Command employed 20 RB-57D aircraft from 1956 until 1964. Little is known about their use. The aircraft were retired due to structural fatigue and the advent of the U-2 and SR-71.^[12]

For many years two WB-57F Canberras (NASA 926 and NASA 928) were flown and maintained by NASA for high altitude atmospheric research. These same two aircraft also deployed alternately to Afghanistan for use as communications platforms that fly high over an area linking various communications devices on the battlefield and in the air. This is the Battlefield Airborne Communications Node system (BACN).^[13] In 2011 it was determined that a third aircraft was needed to satisfy mission requirements and an additional WB-57 was removed from the 309th AMARG after over 40 years at Davis-Monthan AFB and returned to flight status in August 2013 as NASA 927. ^[14]

Vietnam War

See also: Patricia Lynn Project

Although intended as a bomber and never before deployed by the USAF to a combat zone, the first B-57s to be deployed to South Vietnam were not operated in an offensive role. The need for additional reconnaissance assets, especially those capable of operating at night, led to the deployment of two RB-57E aircraft on 15 April 1963. Under project Patricia Lynn these aircraft provided infrared coverage using their Reconofax VI cameras.^[15] Later in August 1965, a single RB-57F would be deployed to Udon, RTAB in an attempt to gather information about North Vietnamese SAM sites, first under project Greek God and then under project Mad King. In December another RB-57F would be deployed for this purpose, under project Sky Wave. Neither project garnered useful results and they were terminated in October 1965 and February 1966 respectively.^[16]

The deployment of actual combat capable B-57Bs from 8th and 13th Bomb Squadrons to Biên Hòa in August 1964 began with two aircraft lost and one damaged in collisions on arrival.^[17] An additional five aircraft were destroyed with another 15 damaged by a Viet Cong mortar attack in November of the same year. Low level sorties designated as training flights were conducted with the hope of it having a psychological effect. As a result the first combat mission was only flown on 19 February 1965.^[18] The first excursion into North Vietnam took place on 2 March as part of Operation Rolling Thunder. The aircraft typically carried nine 500 lb (227 kg) bombs in the bomb bay and four 750 lb (340 kg) bombs under the wings. In April, Canberras began flying night intruder missions supported by USAF's Fairchild C-123 Provider or Lockheed C-130 Hercules flare ships and USN's EF-10B Skyknight electronic warfare aircraft.

U.S. B-57 Canberras were primarily used for dive bombing and strafing, with the early models mounting eight .50 caliber machine guns, four per wing. Later models mounted four 20mm cannons, two per wing, for strafing. These weapons combined with their bomb loads, and four hours of flight time made them excellent ground support aircraft, as well as exceptional truck killers along the Ho Chi Minh trail.^[19] Deployed along the notorious "trail" for much of their eight years in Vietnam, Canberras participated in truck hunting campaigns during operations Barrel Roll, Steel Tiger, and Tiger Hound, gaining reputations with their "Centurion Club" which consisted of Canberra crews which attained 100 truck kills.^[20]

On 16 May 1965, an armed B-57B exploded on the runway at Biên Hòa, setting off a chain reaction that destroyed 10 other Canberras, 11 Douglas A-1 Skyraiders, and one Vought F-8 Crusader. Due to combat attrition, in October 1966, B-57Bs were transferred to Phan Rang where they supported operations in the Iron Triangle along with Australian Canberra B.20s. The aircraft also continued to fly night interdiction missions against the Ho Chi Minh trail. Of the 94 B-57Bs deployed to Southeast Asia, 51 were lost in combat and seven other Canberras were lost to other causes. Only nine were still flying by 1969.^[21]

B-57s returned to Southeast Asia in the form of the Tropic Moon III B-57G, deployed to Thailand during the fall of 1970.^[22] Intended as a night intruder to help combat movement along the Ho Chi Minh trail, these aircraft were equipped with a variety of new sensors and other equipment, and were capable of dropping laser guided munitions.^[23] The relative kill rates per sortie during Operation Commando Hunt V between the B-57G and the AC-130A/E showed that the former was not as suited to the role of trucker hunter.^[24] An attempt to combine both led to one B-57G being modified to house a special bomb bay installation of one Emerson TAT-161 turret with a single M61 20mm cannon as a gunship under project Pave Gat. After delays in testing at Eglin AFB, Florida, due to competition for mission time from the Tropic Moon III B-57Gs, Pave Gat tests proved "that the B-57G could hit stationary or moving targets with its 20mm gun, day or night. Loaded with 4,000 rounds of ammunition, the Pave Gat B-57G could hit as many as 20 targets, three times as many as the bomb-carrying B-57G. The Pave Gat aircraft could avoid antiaircraft fire by firing from offset positions, while the bomb carrier had to pass directly over the target." Deployment to SEA was resisted, however, by the Seventh and Thirteenth Air Forces and others as the decision had been made in August 1971 to return the B-57G squadron to the U.S. in early 1972, leaving insufficient evaluation time. Project Pave Gat was terminated 21 December 1971.^[25] The B-57G was removed from Thailand in May 1972. Plans remained for the continuation of the B-57G program but post-conflict spending cuts forced the abandonment of these plans.^[26]

For a short period South Vietnamese Air Force personnel operated four B-57B aircraft. The VNAF never officially took control of the aircraft, and, after accidents and other problems, including apparent claims by VNAF pilots that the B-57 was beyond their physical capabilities, the program was terminated in April 1966, and the aircraft were returned to their original USAF units.^[27]

B-57 Canberra losses during the Vietnam War^[28]

Lost to Ground Fire	Lost to Mortar Fire/Ground Attack	Lost to Mid Air Collision	Lost to Airfield Accidental Bomb Explosion	Lost to Operational Causes	Lost to Unknown Causes
26	5	4	10	7	6	Total: 58

Figures include two B-57E Canberras from the 1st Det 33rd Tactical Group.

Pakistan

The Pakistan Air Force was one of the main users of the B-57 and made use of it in two wars with India. In the Second Kashmir War of 1965, B-57s flew 167 sorties, dropping over 600 tons of bombs. Three B-57s were lost in action, along with one RB-57F electronic intelligence aircraft.^[29] However, only one of those three was lost as a result of enemy action.^[30] During the war, the bomber wing of the PAF was attacking the concentration of airfields in north India. In order to avoid enemy fighter-bombers, the B-57s operated from several different airbases, taking off and returning to different bases to avoid being attacked.^[31] The B-57 bombers would arrive over their targets in a stream at intervals of about 15 minutes, which led to achieving a major disruption of the overall IAF effort.^[30] PAF's B-57 Squadron was the first to form a regular formation aerobatics team of four such aircraft.^[32] The unknown Pakistani flying ace, 8-Pass Charlie, was named by his adversaries for making eight passes in the moonlight, to bomb different targets with each of the B-57's bombs.^[33][34]

During the Indo-Pakistani War of 1971, the PAF again made use of the B-57. On the very first night, 12 IAF runways were targeted and a total of 183 bombs were dropped rendering the Indian airfields useless for 6 hours to 6 days.^[35] As the war progressed, PAF B-57s carried out many night missions. There was a higher attrition rate than in 1965, with at least five B-57s being put out of service by the end of the war.^[29][36] They were retired from PAF service in 1985.

Variants

B-57A

First production version; eight built.

B-57B

Definitive production version, tandem cockpit, 8x 0.50 in (12.7 mm) machine guns or 4x 20 mm cannons, four underwing hardpoints; 202 built.

B-57C

Dual-control trainer, first flight: 30 December 1954; 38 built.

B-57E

Target tug, first flight: 16 May 1956; 68 built.

B-57G

B-57Bs modified as night intruders with FLIR, LLTV and laser designator in the nose, capable of using laser-guided bombs; 16 converted.

EB-57A

Electronic aggressor aircraft converted from RB-57As.

EB-57B

ECM aircraft converted from B-57Bs.

EB-57D

ECM aircraft converted from RB-57Ds.

EB-57E

Electronic aggressor aircraft converted from RB-57Es.

RB-57A

Photo reconnaissance version with cameras installed aft of the bomb bay; 67 built. RB-57A avionics included an AN/APS-11A transponder and AN/APA-90 Indicator Group for command guidance (LEFT, RIGHT, CLIMB, DESCEND, BOMB, etc.) and was tested for "MSQ-1 controlled pinpoint photography" in 1954 ("Night Photo Bombing" capacity was 21 M-120 Photoflash Bombs).^[37]

RB-57B

Photo-reconnaissance aircraft converted from B-57Bs.

RB-57D

see: Martin RB-57D Canberra

High-altitude strategic reconnaissance version, J57-P-9 engines, wingspan increased to 105 ft (32.00 m), first flight: 3 November 1955; 20 built.

RB-57E

see: Patricia Lynn Project

B-57Es modified to all-weather reconnaissance aircraft, used in "Patricia Lynn" missions during the Vietnam War; six converted.

RB-57F

see: Martin RB-57F Canberra

High-altitude strategic reconnaissance version developed by General Dynamics. Pratt & Whitney TF33 turbofan engines, wingspan increased to 122 ft (37.5 m), first flight 23 June 1963; 21 built.

WB-57D

Air Weather Service RB-57Ds used for nuclear atmospheric sampling testing.

WB-57F

Air Weather Service RB-57Fs re-designation after June, 1968

Operators

 Pakistan

• Pakistan Air Force
  • No. 31 Bomber Wing ^[38]
    • No. 7 Squadron Bandits
    • No. 8 Squadron Haiders

 Republic of China

• Republic of China Air Force

 United States

• United States Air Force

List of B-57 units of the United States Air Force

• NASA
• NCAR/High Altitude Mapping Missions, Inc,^[39]
• National Oceanic and Atmospheric Administration of the United States Commerce Department^[40]

Aircraft on display

.

RB-57A

• 52-1426 - Yankee Air Museum in Belleville, Michigan.^[41]

• 52-1446 - Glenn L. Martin Maryland Aviation Museum, Middle River, Maryland.^[42]

• 52-1456 - Selfridge Military Air Museum and Air Park, Selfridge ANGB, Michigan.^[43]

• 52-1467 - Glenn L. Martin Maryland Aviation Museum, Middle River, Maryland.^[44]

• 52-1475 - Museum of Aviation at Robins AFB, Georgia.^[45]

• 52-1482 - USAF History and Traditions Museum, Lackland AFB, San Antonio, Texas.^[46]

• 52-1485 - Selfridge Military Air Museum and Air Park, Selfridge ANGB, Michigan.^[47]

• 52-1488 - New England Air Museum, Windsor Locks, Connecticut.^[48]

• 52-1492 - Hill Aerospace Museum at Hill AFB, Utah. In April 1968, this aircraft was delivered to the National Museum of the United States Air Force at Wright-Patterson AFB in Dayton, Ohio, and was displayed there until 1982.^[49]

B-57B

• 52-1576 - Air Force Flight Test Center Museum, Edwards AFB, California.^[50]

• 52-1584 - Kalamazoo Aviation History Museum, Kalamazoo, Michigan.^[51]

EB-57B

• 52-1499 - National Museum of the United States Air Force, Wright-Patterson AFB, Dayton, Ohio. This aircraft was assigned to Wright-Patterson Air Force Base in Dayton, Ohio as a test aircraft in the early 1960s. In 1965, it was returned to combat configuration to replace combat losses in Southeast Asia. It was assigned to the 8th Bomb Squadron at Phan Rang AB, South Vietnam in 1967, where it flew combat missions for 2½ years. Upon return to the United States, it was converted to an electronic countermeasures EB-57B and was flown to the museum in August 1981. It is on display in the Museum's Modern Flight gallery where it replaced an RB-57A (AF Ser. No. 52-1492) that had been on display at the Museum since April 1968. In 2012 Museum staff reconverted it to stock B-57B configuration and placed it back on display.^[52]

• 52-1500 - Vermont Air National Guard's Burlington ANGB (158th Fighter Wing) at Burlington International Airport in Burlington, Vermont.^[53]

• 52-1504 - Dyess Linear Air Park, Dyess AFB, Texas.^[54]

• 52-1505 - Malmstrom AFB Museum and Air Park, Malmstrom AFB, Montana.^[55]

• 52-1509 - Laughlin AFB, Texas.^[56]

• 52-1516 - Air Force Armament Museum at Eglin AFB, Florida.^[57]

• 52-1519 - March Field Air Museum, March ARB, Riverside, California.^[58]

• 52-1526 - Edward F. Beale Museum, Beale AFB, California.^[59]

• 52-1548 - South Dakota Air and Space Museum, Ellsworth AFB, Rapid City, South Dakota.^[60]

RB-57D

• 53-3982 - National Museum of the United States Air Force at Wright-Patterson AFB in Dayton, Ohio. This is one of the 13 photo reconnaissance RB-57Ds. It is painted as it appeared in the late 1950s while serving in the 4025th Strategic Reconnaissance Squadron (L). It went on display in the Museum's Cold War gallery in 2004.^[61]

B-57E

• 55-4244 - Strategic Air and Space Museum in Ashland, Nebraska.^[62]

• 55-4274 - Pima Air and Space Museum adjacent to Davis-Monthan AFB in Tucson, Arizona.^[63]

EB-57E

• 55-4253 - Castle Air Museum (former Castle AFB) in Atwater, California.^[64]

• 55-4279 - Peterson Air and Space Museum at Peterson AFB in Colorado Springs, Colorado.^[65]

• 55-4293 - Wings Over the Rockies Air and Space Museum in Denver, Colorado.^[66]

WB-57F

• 61-13501 - Pima Air & Space Museum adjacent to Davis-Monthan AFB in Tucson, Arizona.^[67]

• 63-13293 - Museum of Aviation at Robins AFB, Georgia.^[68]

Specifications (B-57B)

Data from Quest for Performance^[69]

General characteristics

• Crew: 2 (pilot,navigator )
• Length: 65 ft, 6 in (20.0 m)
• Wingspan: 64 ft 0 in (19.5 m)
• Height: 14 ft 10 in (4.52 m)
• Wing area: 960 ft² (89 m²)
• Empty weight: 27,090 lb (12,285 kg)
• Loaded weight: 40,345 lb (18,300 kg)
• Max. takeoff weight: 53,720 lb (24,365 kg)
• Powerplant: 2 × Wright J65-W-5 turbojets, 7,220 lbf (32.1 kN) each
• *Zero-lift drag coefficient: 0.0119
• Drag area: 11.45 ft² (1.06 m²)
• Aspect ratio: 4.27

Performance

• Maximum speed: Mach 0.79 (598 mph, 960 km/h) at 2,500 ft (760 m)
• Cruise speed: 476 mph (414 knots, 765 km/h)
• Stall speed: 124 mph (108 knots, 200 km/h)
• Combat radius: 950 mi (825 nm, 1,530 km)with 5,250 lb (2,380 kg) of bombs
• Ferry range: 2,720 mi(2,360 nm, 4,380 km)
• Service ceiling: 45,100 ft (13,745 m)
• Rate of climb: 6,180 ft/min (31.4 m/s)
• Wing loading: 42 lb/ft² (205 kg/m²)
• Thrust/weight: 0.36
  
• Lift-to-drag ratio: 15.0

Armament

• Guns: 4× 20 mm (0.787 in) M39 cannon, 290 rounds/gun
• Bombs: ** 4,500 lb (2,000 kg) in bomb bay, including nuclear bombs
  • 2,800 lb (1,300 kg) on four external hardpoints, including unguided rockets

Avionics

• APW-11 Bombing Air Radar Guidance System
• SHORAN bombing system
• APS-54 Radar Warning Receiver

See also

Related development

• English Electric Canberra
• Martin RB-57D Canberra
• Martin/General Dynamics RB-57F Canberra

Aircraft of comparable role, configuration and era

• Avro CF-100
• Ilyushin Il-28
• Martin XB-51
• North American AJ Savage
• North American B-45 Tornado

Related lists

• List of bomber aircraft
• List of military aircraft of the United States

References

Notes

Bibliography

External links

Wikimedia Commons has media related to B-57 Canberra.

• NASA / JSC High Altitude Research Program

v t e Glenn L. Martin Company and Martin Marietta aircraft Model numbers 66 67 70 123 130 139 145 146 156 162 166 167 170 179 182 187 190 210 219 223 234 237 247 270 272 316 Airliners M-130 202 303 404 Attack aircraft A-15 A-22 A-23 A-30 A-45 AM Bombers B-10 B-12 XB-13 XB-14 XB-16 B-26 XB-27 B-33 B-48 XB-51 B-57 XB-68 BM MB Maritime patrol PBM P4M P5M P6M Military transports C-3 JRM RM Military trainers T/TT N2M Scout/Torpedo bombers S MS TM T2M T3M T4M T5M T6M Reconnaissance aircraft RB-57D RB-57F Martin Marietta 845 SV-5J X-23 X-24A X-24B

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