The B-47B differed from the B-47A in many ways. It carried J47-GE-23 engines (6 of them) and solid fuel rockets for assisted take off. It had a Nesa glass (Trade name of glass coated with a transparent chemical conductor of electricity. Nesa glass, therefore, was easily kept free of ice.) windshield with rain repellant (in lieu of impractical windshield wipers), hydraulic boost on all control surfaces, a spoiler door (at the aircraft's main entrance) to ease in flight escape, plus a single point ground and air to air refueling receptacle. Finally, it featured a 2 gun tail turret controlled by radar sight, a B-4 fire control system, a K-4A bombing-navigational system, an AN/APS-54 warning radar, and many other improved electronic components, including AN/APT-5A electronic countermeasure devices. Some B-47Bs were equipped with special reconnaissance pods. The Boeing developed, 8-camera pod could easily be installed in the forward bomb bay, but only provided daylight photographic coverage.
Design of the B-47B started 5 years after Boeing began work on a multi-jet aircraft for photoreconnaissance and bombing missions with conventional weapons. The informal photographic reconnaissance requirements of 1943 were dropped the following year, when the need for a new medium bomber was clearly established. But by the time Boeing received a production go ahead, circumstances had changed. The Air Force now wanted its new jet bomber to carry atomic weapons as well as conventional bombs. The mounting urgency to build an atomic deterrent force despite the lack of funds posed grave problems in the fall of 1948. While the B-36 program was no longer in jeopardy, other programs had to be canceled or drastically reduced. Faced with far reaching decisions, the Air Force opted for the faster production of a more versatile and atomic capable B-47. This approach was not new. Back in 1946, the AAF had decided that all new planes capable of carrying bombs as heavy as the atomic bomb should be able to carry the A-bomb itself. Yet, long after the atomic attacks against Japan, the secrecy shrouding the bomb persisted. As in the B-36's case, this would be of no help to B-47 development. In addition, the photo reconnaissance requirements of several years past were revitalized.
The Air Force accepted this plane in March 1951 and 87 similar productions within a year. The 88 planes, like the B-47As, featured 6-J47-GE-11 engines until re-fitted with the more powerful J47-GE-23s that equipped subsequent B-47Bs. Testing by WIBAC in late July 1951 verified that the new B-47Bs could not possibly meet the Strategic Air Command's requirements.
The first SAC B-47B (Serial No. 50-008) was flown on 23 October 1951 from Wichita to MacDill by Col. Michael N. W. McCoy, Commander of the 306th Wing. Even though the plane was not combat ready, a beginning had been made and this was celebrated on 19 November, when the aircraft was named "The Real McCoy." Six more B-47Bs programmed for the 306th during that month were refused because of serious deficiencies, but a total of 12 were accepted before the end of the year.
In September, USAF test pilots pointed out that the plane's weight gain, from 125,000 to 202,000 pounds, had badly affected its flying qualities, making it unstable at high altitude and generally hard to maneuver.
Following extensive modifications (See Design Problems) fifty two RB-47s and 510 B-47Bs were ordered in June 1952, and 3 other production contracts were issued during the year. One in September called for 540 B-47Bs; 1 in October, for 70 RB-47s; and 1 in December, for another 193 B-47Bs. As it turned out, the Air Force reduced the number of B/RB-47s (1,760 aircraft) ordered in 1952, and most of these aircraft came off the production line as B-47Es.
SAC received 8 modified B-47Bs in October 1952, 23 in November, 34 in December, and 13 in January 1953. The aircraft immediately went to the 306th and 305th Wings.
A total of 397 B-47Bs were accepted. Ten of these aircraft were built by Douglas, 8 by Lockheed, and all others by Boeing.
The Air Force accepted 2 B-47Bs in fiscal year 1951 (1 each in April and May 1951); 204 in FY 52; 190 in FY 53, and a last one in FY 54 (July 1953).
The B-47B had a Flyaway Cost per Production Aircraft of $2.44 million-Airframe, $1,767,094; engines (installed), $283,082; electronics, $43,835; ordnance, $5,336; armament, $350,109.
Design of the RB-47B was started in March 1951. Based on experience, the aircraft's first flight was expected 2 years later. The Air Force at the time also figured that delivery of the new reconnaissance planes could well begin in mid 1953. Yet, in March 1952, the many problems associated with the bomber configuration implied that the reconnaissance B-47 the Air Force had in mind was a long way off. In fact, it was decided shortly before October 1952 that the plane would feature the scarce A-5 fire control system and the still experimental J47-GE-25 engines. The aircraft, therefore, most likely would not be completed until 1954 and when available, it would have little in common with the basic B-47B. Closely resembling the new E model, it would come to be known as the RB-47E.
While this marked the production demise of the RB-47B (which never appeared on the Air Force's financial accounts), so called RB-47Bs and YRB-47Bs came into being to fill SAC's reconnaissance vacuum of the early fifties. These planes, however, were nothing more than converted B-47Bs, equipped with special reconnaissance pods. The Boeing developed, camera pod could easily be installed in the forward bomb bay, but only provided daylight photographic coverage. The 91st Strategic Reconnaissance Wing (Medium) received its first YRB-47 in April 1953; the 26th, 3 months later. Most of the 90 converted reconnaissance planes were subsequently used as crew trainers for operational RB-47Es.
In effect, the B-47Bs ceased to exist in 1957. By then, most of these aircraft had been brought up to the 731st's configuration.
The B-47Bs were entirely phased out by 1957.
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