The RB-57 is a reconnaissance version of the B-57. The B-57 is a modified version of the English Electric Canberra which was first flown in Britain on May 13, 1949, and later produced for the Royal Air Force. After the Korean Conflict began in 1950, the USAF looked for a jet medium bomber to replace the again Douglas B-26 Invader. In 1951, the United States broke a long-standing tradition by purchasing a foreign military aircraft to be manufactured in quantity for the US Air Force.
The single-seat RB-57D featured a substantially altered B-57B fuselage, new wings, more powerful engines, and components that varied, according to the aircraft's many specialized roles. Specifically, the fuselage bomb-bay was permanently closed off, the fuselage fuel tanks were removed, and 4 camera windows were installed forward of the nose wheel well. The RB-57D's large nose and tail radomes further lengthened the fuselage. The aircraft empennage incorporated a power-driven rudder and yaw damper. Fuel cells were integral with the RB-57D wing, which was of honeycomb construction-the first time that such a structural feature had been used in a piloted aircraft. The new wings, with their 105-foot span and their 1,500 square-foot area (replacing the 64-foot span and 960 square-foot area of the regular B-57), completely changed the appearance of the airplane.
The RB-57D initially housed two 7,200 lb static thrust J65 engines that gave the RB-57D a maximum ceiling of about 65,000 ft. However, the RB-57Ds were later re-fitted with either two J57-P-9 engines or two J57-P-27 engines, both giving the RB-57D much more power. The J57-P-9 boasted 10,000 lbs of static thrust, giving the RB-57D a ceiling of about 70,000 ft. The J57-P-27 exerted 10,500 lbs of thrust giving a ceiling of 67,900 ft. In addition to these new engines, the RB-57D was equipped with anti-icing equipment that could be used at altitudes over 65,000 feet. Furthermore, to increase range, all but the first 6 RB-57Ds were equipped for air refueling.
Martin's Model 294, which ultimately became the RB-57D, developed from a study concluded in December 1952 by the Wright Air Development Center. This study showed that it should be possible to develop "in a relatively short time period" a turbojet-powered special reconnaissance aircraft, with a radius of 2,000 nautical miles at altitudes of 65,000 feet. Anticipating a formal requirement for such an aircraft, the center established design Project MX-2147, which also specified that subsonic speed would be acceptable and that no defense armament would be required.
The advertisement of Project MX-2147 in April 1953 was followed by the award of 3 design contracts-to Bell, Fairchild, and Martin. The Martin study contract was initiated by a June 29, 1953 letter contract, amounting to $31,406. This document, as revised in October, bound Martin to submit reports on its design study by 11 December 1953 and allowed a $2,784 cost increase.
The Air Force decided in June of 1954 that 6 of the B-57Bs currently on order would be built in the configuration of Model 294. The decision was based on several factors. Martin's high altitude design offered "relatively good performance, an operational date 12 to 18 months earlier, and lower costs" than Bell's X-16.2' Martin's new planes, designated B-57Ds in August 1954, became RB-57Ds in April 1955-after the Air Force made it known that the airplanes would be used exclusively for strategic reconnaissance.
January 3, 1955, the Air Force increased the specialized reconnaissance B-57D program to 20 airplanes-the final total-and attached an overriding priority to the whole project. The forthcoming RB-57Ds, all destined for the Strategic Air Command, were ordered in 3 versions. The original 6, plus 6 of the additional 14, would be 1-man RB-57Ds carrying among other components 2 K-38 and 2 KC-1 split vertical cameras. One RB-57D, singled out as the RB-57D-1, would be equipped with the AN/APG-56 high-resolution, side-looking radar for day or night radar mapping reconnaissance. The RB-57D-1 would also carry a crew of 1. The remaining 6 RB-5713s, identified as RB-57D-2s, would be fitted with ferret electronic countermeasures equipment and would have a crew of 2-pilot and electronic countermeasures operator. All but the first 6 airplanes would be equipped for in-flight refueling by KC-97 tankers. Air-refueling would be done via a boom slipway door, aft of the canopy. The 20 RB-57Ds would have an autopilot and the D-1 and D-2s would feature the AN/APN-59 navigational equipment.
The Air Force intended to carry Martin's high-altitude B-57 on Contract AF 33(600)-22208, which followed the first definitive contract-AF 33(038)-22617-initiated by the letter contract of March 1951. However, negotiations for this second contract, like those of its predecessor, were complicated by the many changes that kept on afflicting the whole B-57 program. After discovering that less than 20 percent of the new aircraft's parts matched those of the B-57B, the Air Force had to alter its plans. The programmed quantity of B-57Bs was reduced by 20, and the 20 airframes (completed to the extent components were common to both B and D airplanes) were booked against contract AF 33(600)-25825, even though this document had been designed to cover nothing more than a pure development study. The stripped-down airplanes, transferred on paper as government-furnished equipment, were valued at $6 million. This sum, like subsequent costs for the D airplanes, was charged to the AF 33(600)-25825 development contract. This cost-plus-fixed fee agreement was allowed a high fixed fee rate of 7 percent, because of the program's urgency and the many imponderables faced by Martin in undertaking such a project. In early 1958 the total estimated cost of the entire D program was about $60 million-$1 million short of the final amount.
The high-altitude, daylight photo-reconnaissance RB-57D was first flown on 3 November 1955. The flight lasted 50 minutes and the results were satisfactory.
Because of the urgency of the program for which the RB-57Ds were built, flight testing had to be limited and all tests ended in 1956. To begin with, Category II testing (a joint contractor-USAF effort) was not allowed to linger. Started on 29 November 1955, these tests were completed on 7 December. Just the same, RB-57D deliveries slipped to the spring of 1956.
It took until May 1956 for Strategic Air Command (SAC) to get its first RB-57Ds, even though the aircraft had been scheduled for delivery in late 1955. Strikes at Lear, Incorporated, which supplied the radars, caused delays in equipping the aircraft. Westinghouse, another main subcontractor, also had labor problems that created a shortage of autopilots. But the overall situation improved. By the end of September, SAC's inventory counted 11 RB-57Ds. Four B-57C trainers, brought up to the reconnaissance configuration, accompanied the new aircraft.
Material deficiencies accounted for 20 of 22 unsatisfactory sorties, flown during June 1957 by the specialized RB-57Ds of the 4025th Strategic Reconnaissance Squadron. The Pratt and Whitney J57-P-9 engines, Westinghouse autopilots, and some of the more complicated electronic countermeasures systems did not function properly. In addition, it was difficult to obtain parts for the new electronic countermeasures components. The greatly enlarged wing also kept causing problems. First, the main wing spar had to be strengthened as did sections of the wing panels. Then, the Martin-developed "honey-comb" wing surfaces were subject to water seepage and wing stress. These shortcomings taken care of, the RB-57Ds served SAC's purposes well for several years.
The RB-57D production ended in December 1956, but the Air Force did not take delivery of the last plane before March 1957.
A total of 20 RB-57Ds were accepted.
The Air Force accepted 12 RB-57Ds in FY 56 and 8 in FY 57.
The RB-57D had a flyaway cost per production aircraft of $3.05 million-Airframe, $2,531,437; engines (installed), $313,974; electronics, $171,271; others, $39,750.
On 24 December 1957, a USAF RB-57 was shot down by Soviet fighters over the Black Sea, and in February 1958 and October 1959 RB-57Ds operated by the Chinese Nationalists were shot down over Communist Mainland China. On 14 December 1965 (1968 according to other accounts) an RB-57F was shot down by a SAM over the Black Sea near Odessa. The two crewmembers remained missing.
Other B-57s served as tactical aircraft in Vietnam. One very unique feature about the B-57 was its rotating bomb bay door. The bombs were loaded on the door assembly itself which would rotate completely inside the bomb bay prior to weapon release. The EB-57B electronic warfare version dispensed chaff to jam hostile radar transmissions. Other B-57s were used to tow targets and as transitional trainers for jet aircrews.
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