As an intended replica of the English Electric Canberra B. Mk.2, the B-57A featured no outstanding innovations. Nonetheless, because of the American mass production methods, standards, and uses of different materials, tools, gauges, wiring, and techniques, the plane differed from its British pattern in several aspects. The B-57A had a slightly modified cockpit and canopy that afforded better visibility and more room for the crew (reduced from 3 to 2). Two Wright Aeronautical J65 turbojet engines were substituted for the Canberra's 2 Rolls Royce Avon turbojets. Other changes included the addition of wing tip tanks (to increase loiter time) and replacement of the British "clam shell" type bomb bay doors. Developed by Martin for the B-57A, the pre-loaded revolving bomb bay door rotated 180 degrees and eliminated the drag caused by an opened bomb bay compartment during the bombing run.
Although the Wright J65 Sapphire engine,(The Sapphire was a hand tooled production of the British firm Armstrong Siddeley for which the Curtiss Wright Corporation at Wood Ridge, N. J., had acquired a manufacturing license. Production of the Wright YJ-65, as the Sapphire engine was redesignated, was not expected to begin before September 1951.) due to power the B-57, and some equipment the Air Force wanted on the airplane would be furnished by the government, the urgent delivery schedules specified by the production letter contract of March 1951 presented difficult tasks. As a result, Martin began immediately to plan ahead and on 1 July subcontracted 60 percent of the actual production work. Its principal subcontractors were the Kaiser Products of Bristol, Pennsylvania, for the wings and special weapons bomb bay doors; and the Hudson Motors Corporation of Detroit, Michigan, for the aft portions of the plane.
Martin tested its first British Canberra from April to October 1951, accumulating 41 hours of flying time in the process: The second imported plane reached Martin in September, was test flown not more than 4 hours, and disassembled. Appropriate sections of the plane were then shipped to Martin's main subcontractors. Eventually reassembled. this Canberra went to the Sampson AFB Museum, Geneva. N.Y, on 2 June 1954. It was scrapped 2 years later. USAF pilots began test flying the first Canberra in the fall of 1951. A 21 December accident, in which the plane was completely destroyed, accounted for some of the slippage that plagued the B-57 program from the start.
The Mockup Board's inspection of the B-57A was not an overwhelming success. The board approved the location of the eight .50 caliber forward firing guns (placed in the wings instead of the fuselage nose), but noted numerous shortcomings. It also pointed out that the aircraft would have to be modified to carry special weapons, that a compatible bombing system was required, and that pylons were needed to support external stores. Particularly dissatisfied with the B-57A cockpit, the board insisted that it should be redesigned.
The Aircraft laboratory of the Wright Air Development Center examined Martin's first B-57 specifications in August 1951. The laboratory was well prepared for its chores. In January, it had thoroughly evaluated the Canberra and indicated that an Americanized production from the British drawings and data would not satisfy USAF requirements. In August, the laboratory's criticism grew. Besides sharing the mockup board's concern, it found fault with the aircraft's landing gear, the brake actuating system, the absence of winterization, and many other items. Moreover, the laboratory concluded that, as currently planned, Martin's tip tank installation, engine mounting, and nose gear swivel angle would be inadequate.
In January 1952, Wright Air Development Center decided to challenge the B-57's production philosophy. So far, the center noted, the Board of Senior Officers had approved the correction of only 6 deficiencies. Yet, some of the 35 design faults uncovered by the center's engineers could affect the safety, utility, and maintenance of the future B 57. In fact, the Royal Air Force (RAF) had refused to accept the Canberra from the English Electric Company until many of the very same flaws were eliminated. It therefore appeared inconsistent to carry any of these deficiencies into the American production of the plane. At first, Wright Center's position was not well received. Air Materiel Command was quick to point out that the center previously had made no attempt to integrate its list of deficiencies into the production schedule of the plane, even though it made no sense to discuss one without the other. Any configuration changes adopted at this late date, AMC emphasized, would cause unacceptable production delays. Moreover, in the command's opinion, several of the corrections suggested by the air development center were superfluous, at least for the B 57A. The Air Materiel Command agreed, however, that the B 57 production guidelines ran counter to the USAF regulations calling for technical excellence. Another month of debate failed to alter the production restrictions of March 1951, but it did bring AMC around to support Wright Air Development Center's position. And, as events soon proved, the center's effort would have significant impact on the program.
On 11 August 1952, production of the B-57A's reconnaissance version, ordered earlier in the year, was reduced by one third. More importantly, and to Wright Air Development Center's great satisfaction, procurement of the B-57A was virtually canceled. Only 8 B-57AS would be built. Despite slight alterations, these aircraft would be recognized as direct copies of the Canberra. As actually recommended 2 years before by the Boyd Committee, the B-57A would be used for testing, thereby paving the way for production of a similar but better aircraft.
The unexplained Canberra loss of late 1951 and ensuing testing setback undoubtedly accounted for part of Martin's production slippage. But a major initial delay was caused by the government furnished Sapphire jet engines that were due to power all B-57s. The Sapphire was a hand tooled production of the British firm Armstrong Siddeley for which the CurtissWright Aeronautical Division at Wood Ridge N.J., had acquired a manufacturing license. However, the J65, as the Air Force version of the Sapphire was designated, was perhaps more difficult to adapt to American specifications and manufacturing methods than the British plane. Although the Wright production had been set to begin in September 1951, the J65 prototype engines consistently failed to meet USAF requirements. The new engine was also earmarked for the Republic F-84F Due to the urgent need for improved fighter bombers since the outbreak of the Korean War, the Air Force in December 1950 selected the Buick Division of the General Motors Corporation as the second source for the Sapphire engine.
In June 1952, when the Air Force finally accepted the first 2 YJ65-W-1 engines, neither had yet completed the required 150 hour qualification test. Still, there were other problems of equal consequence. In April of the same year, a technical status report could only state that the B-57 manufacturer and subcontractors had begun the fabrication of "bits and pieces." In June 1952, while the B-57A basic engineering seemed to be completed, projected test flights were postponed to mid 1953 because of continuing engine and cockpit troubles.
The Martin twin jet B-57A night intruder bomber at long last took to the air on 20 July. Company officials described the 46 minute flight as entirely successful. On 20 August, the plane underwent its official Air Force flight acceptance test at the Martin airfield at Middle River, Maryland. In attendance, among high ranking Air Force officials, were General Twining, Air Force Chief of Staff since 30 June 1953; Lt. Gen. Edwin W. Rawlings, Commander of Air Materiel Command; and Lt. Gen. Donald L. Putt, Commander of Air Research and Development Command. Newspaper accounts of the B-57A performance were enthusiastic, more so than subsequent USAF appraisals.
Relegated to the testing status, none of the B-57A productions entered operational service. Yet, 1 or 2 eventually participated in a few special projects.
The Air Force accepted the first B-57A on 20 August, but lent it immediately to Martin and never took delivery of the plane (This plane (Serial No. 52-1418) remained with the Martin Company from its completion until 19 June 1957, when it was transferred to the National Advisory Committee for Aeronautics. The contractor received the airplane under Bailment Contracts AF 33 (038)-32001 and AF 33 (600)-2407 of 6 August 1953 and 21 February 1956. Martin test pilots flew the plane 292 hours in 284 flights.). Hence, USAF testing did not start until December 1953, when all other B-57As were delivered. Once underway, however, testing was extensive. USAF pilots test flew the second B-57A (Serial No. 52-1419) for no less than 101 hours, reached in 80 flights. While testing would go on for years, by late 1954 the Air Force knew without doubt that the B-57A was somewhat superior to the original Canberra. Yet the overall improvement carried a price. Added equipment and the more powerful J65 engines had increased the aircraft's empty weight by 3,700 pounds, in turn reducing speed, distance, and altitude.
All B 57As were received in FY 54. The Air Force accepted but never physically possessed the first B 57A in August 1953. It took delivery of the remaining 7 in December.
The B-57A had a flyaway cost per production model of $9.3 million-Airframe, $8,937,886; engines (installed), $349,357; electronics, $20,780; ordnance, $7,442; armament and others, $33,704.
The high cost of the B-57A was explained by the fact that only 8 of them were built, and that Martin's initial and one time manufacturing costs were prorated among those first few aircraft. But for rare exceptions, the higher the production, the lower the cost. Although only 67 RB-57As entered the inventory, the reconnaissance B-57A showed a significant price decrease. And despite important improvements, the unit cost of the subsequent and more numerous B-57B was still cheaper.
Attrition, conversions, and special projects gradually absorbed the few B-57As. By mid 1961, the aircraft no longer appeared in the Air Force inventory.
Early in 1957, the Air Force lent the second B-57A to the Weather Bureau of the Department of Commerce. Following modification, the plane participated in the National Hurricane Project.
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