In 1962, research and development studies were initiated on the Low Altitude Manned Penetrating System (LAMPS), redesignated the advanced manned strategic aircraft (AMSA) in 1965. The requirement called for a high-altitude supersonic/low-altitude high subsonic, long-range bomber to replace the B-52 by 1980. The Department issued requests for proposal in November of 1969, and North American Rockwell (now Rockwell International) was selected in 1970 to build three prototype flight test aircraft and one ground test aircraft. An additional flight test aircraft was later procured as a preproduction prototype and funded in the FY 1976 Defense Budget.
The initial study phase was unusually long for two reasons: one was that the Air Force did not want to run into the problems of the B-58 and XB-70, and secondly, and more importantly, Secretary of Defense McNamara preferred ICBMs over bombers. Because he felt the FB-111 would fill the bomber void for the time being, he postponed the B-1 development in 1966 in favor of ICBMs. In testimony before Congress, Secretary of Defense McNamara said, "The strategic missile forces for 1967-71 will provide more force than is required for 'Assured Destruction' . . . a new advanced strategic aircraft does not at this time appear justified." But a change in administration resulted in renewed interest since it was felt that the B-1 aircraft would be in keeping with President Nixon's revised flexible response strategy that required a credible response across a broad range of options short of general nuclear war.
The first B-1A rolled out on October 26, 1974 and made its maiden flight on December 23, 1974. In 1974, AIL was awarded the development contract for the B-1 ECM system; the most comprehensive ECM program ever initiated. The development schedule was in excess of 4 years and was for a 77 Line Replaceable Unit (LRU) band 4 through 7 system. AIL Subcontractors included Litton, Sedco, Northrop, and Tasker. The third prototype, designed as an avionics testbed, carried the initial AIL AN/ALQ-161.
Production of an original quota of 244 B-1 aircraft was funded in the FY 1978 Defense Budget approved by the Ford Administration. On June 30, 1977, President Carter canceled the production of the B-1 as the priority shifted to the development of the cruise missile. AIL's development was only partially complete when the B-1 Program was terminated.
Cancellation led to new DoD studies designed to evaluate alternative aircraft to serve as cruise missile carriers. These studies yielded a B-1 derivative as a best candidate solution. Congress authorized and appropriated funding in the FY 1981 Defense Budget for a multi-role strategic bomber. The final USAF study led to the selection of the derivative B-1B as the nation's next strategic bomber.
The Rockwell design incorporated the FB-lll swing wing which provided both high- and low-altitude performance. High-altitude flight was designed at Mach 2 plus and low altitude at high subsonic speed with supersonic dash capability. The weapons load was to be greater than the B-52 for nuclear bombs, conventional bombs, and SRAMs. The range was designed to be equivalent to the B-52 but with a lower total gross weight and a much shorter takeoff ground roll. This would have permitted much more flexibility in basing since the B-52 is limited by its heavy gross weight and long takeoff ground roll. The avionics systems were to be integrated and under the control of computer processors, a feature considered especially important for changing ECM systems computer programs that, in turn, could provide additional flexibility for continually modifying ECM gear with limited hardware changes. Space capacity was designed in for future modifications, and 244 B-l's were to be built. Four prototypes were developed, the B- 1A models.
The B-1A design includes four jet engines with afterburner, with two jet engines located under each wing root. The fuselage and wing are blended together, and the variable geometry allows a 15 wing sweep in the forward position and 67.5 when fully swept. The B-1A employs a sensor-controlled automatic system, using movable foreplane vanes to combat low level turbulence. The three bomb bays are capable of carrying eight SRAMs or 25,000 pounds of nuclear or conventional bombs each. In addition, there are four external hard points each capable of carrying two SRAMs or 10,000 pounds of bombs. The B-1A has a crew of four: pilot, copilot, offensive systems operator, and defensive systems operator. Originally, the crew was in an escape module, but ejection seats were substituted to save cost and weight. The B-1A has a length of just over 150 feet, a wing span of 136 feet, 8.5 inches in a fully spread configuration and 78 feet, 2 inches in a swept mode, with a height of 33 1/4 feet, 7 inches. The maximum gross takeoff weight is 395,000 pounds. The engines have a self-start capability and, therefore, do not require cartridge start.
Alert reaction time for safe escape was to be a significant improvement over its predecessors. Terrain following radar would also enable the B-1A to fly at lower altitudes than the B-52 which relied upon a terrain avoidance system. Although President Carter canceled production of the B-1 in 1977, the flight testing continued through 1981 with four prototypes. Cited by the President as a principal reason for his decision was the high unit cost which had grown from original estimates of $30 million to $100 million per aircraft. Consequently, the President elected to produce the ALCM which was deemed less expensive. Also, the ALCM, with an RCS smaller by an order of magnitude, was considered less vulnerable to SAM defenses than the B-1.
|Primary Function:||Long-range, multi-role, heavy bomber|
|Builder:||Rockwell International, North American Aircraft|
|Operations Air Frame and Integration:||Offensive avionics, Boeing Military Airplane; defensive avionics, AIL Division|
|Power Plant:||Four General Electric F-101 GE-100 turbofan engine with afterburner|
|Thrust:||30,000-plus pounds (13,500-plus kilograms) with afterburner, per engine|
|Wingspan:|| 136.7 feet extended forward
78.2 feet swept aft
|Weights:|| Normal Operating 389,800 lbs.
Maximum Take-Off - 395,000 lbs.
Max Speed: Mach 1.2 at sea level (900+ mph)
Max Speed: Mach 2.3 at 50,000 feet (1,450 mph / 1,259 knots)
Cruise speed: 560 mph (487 knots) to 650 mph (1040 Km/H / 560 Kt)
|Range:||6,100 miles unrefueled|
|Ceiling:||Over 30,000 feet (9,000 meters)|
|Crew:||Four (aircraft commander, pilot, offensive systems officer and defensive systems officer)|
24 AGM-69B SRAMconventional bombs:
75,000 lbs internal plus 40,000 lbs external 32 SRAM
|Date Deployed:||Cancelled 1977|
4 built, 2 crashed and 2 on display