Bombers from B-70 to Stealth
Only one new American bomber, the Rockwell B-1A, appeared during the 1970s. It was intended to replace the B-52 for the SAC mission of penetrating enemy defenses to deliver nuclear or conventional weapons on strategic targets.
After several years of Air Force mission-requirement studies, President Nixon’s new Defense Secretary, Melvin Laird, was more sympathetic to a manned bomber program, so in April 1969 the B-1A designation was authorized and on November 3, a Request for Proposals was issued. To rank bids, Air Force Evaluation Boards had increased from three captains and four lieutenants in 1924 to some 600 specialists in 1970, and had returned to a “fly-before-buy” basis which was the pre-1939 system of requiring satisfactory flight-test performance before launching production.
North American Rockwell won the B-1 contract award on June 5, 1970, for five prototypes. Powered by four 29,850-pound thrust General Electric F101 engines with variable intake ramps, the B-1A was two-thirds the size of the B-52, but carried twice the weapons load over a greater range at over twice the high-altitude speed. Low-level attacks, guided by APQ-146 terrain-following radar, could be made at Mach .95 and Mach 2.2 could be reached at high altitudes.
Survival in a surprise missile attack was a prime concern. The B-1A could be dispersed to smaller air bases that could not easily accommodate B-52s and was expected to be able to takeoff from and clear a threatened base within four minutes.
Combining high speed with short takeoff required a swing-wing configuration enabling the wing to fold back, like the F-111, 67.5-degrees during high-speed flight. Four crewmen sat in a self-contained capsule that could be detached for emergency escapes, and a pair of horizontal vanes near the nose was part of a Low-Altitude Ride Control system to reduce the effects of air turbulence.
Each of the three internal weapons bays could accommodate a rotary launcher for eight 2,247-pound AGM-69A missiles, which could be directed by an ASQ-156 system at targets within 100 miles of the aircraft, or up to 50,000 pounds of other stores, such as 12 B-43, 24 Mk 84, 30 M117, or 84 Mk 82 bombs. No guns were carried, but extensive ALQ-161 ECM equipment was provided.
Materials used in the airframe were 41.3% aluminum, 6.6% steel, and 21% titanium, the later percentage limited by cost considerations. Costs also reduced the program on January 18, 1971, to three aircraft and much slippage delayed construction.
Accompanied by an extensive publicity campaign, the first B-1A rolled out of the Palmdale, California, factory on October 26, 1974, before an audience of senior officers, politicians and writers, since the plane’s future depended on political actions. Flight tests began on December 23, joined by a second plane on March 26, 1976, and a third on June 14. By November 1977 the prototypes had made 144 flights, had attained Mach 2.1 (1,350 mph) at 50,000 feet, and been up over ten hours on a single flight. From a performance viewpoint, the B-1A seemed entirely successful and far more capable than the B-52.
Air Force leaders such as Chief of Staff General George Brown advocated the B-1 as necessary to the TRIAD concept, in which land-based and submarine-launched missiles are combined with manned bombers to be a deterrent against hostile attack or threats. Manned bombers offer a flexibility of response impossible for missiles, and the B-1 was seen as “the most efficient and effective manned penetrating weapons system ever conceived.”
The chief obstacle to a production program was the high cost of the 244 aircraft desired by 1986, quoted at $22.9 billion in 1976 for the total program in “then-year” dollars, or more than $84 million per unit, including development and inflation costs. Questions of cost effectiveness arose, comparing this cost with that of the missiles required to destroy the same targets. The nation, which had just expended some $150 billion on the war in Vietnam – enough to pay for several B-1 programs – no longer seemed willing to accept the inflationary costs of a possibly redundant system.
On June 30, 1977, as President Jimmy Carter faced the beginning of his first fiscal year, he canceled the B-1A production program as unnecessary and too expensive, allowing completion of the flight tests and the fourth prototype. Instead, the emphasis was shifted to cruise missiles (ACLM) that could be carried inside modified B-52s, which could then attack targets without themselves penetrating enemy defense areas.
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