Whereas procurement of the B-70 was doubtful even before the prototype flew, the next aircraft designed as a B-52 replacement came much closer to actually entering service’ and did in fact eventually lead to a derived production model. The General Dynamics FB-111A was bought as a replacement for the B-58 and some early B-52s, but although this gave SAC a modern medium bomber, the FB-111 was too small and short-ranged to meet all the service’s needs. Throughout the 1960s, the USAF investigated various heavy bomber concepts, coming to concentrate on an aircraft that could evade Soviet defenses by flying fast at low level, while retaining a high-altitude dash capability. Under the Advanced Manned Strategic Aircraft program, Rockwell International, Boeing, and General Dynamics all put forth competing designs, and in 1969, an airframe contract was awarded to Rockwell, with General Electric to build to the F101 turbofan engines to power it. The new aircraft, to be designated B-1A, was a variable-geometry, four-engined design suitable for both high and low-level missions, and optimized for survivability in a nuclear environment.
Originally, the B-1A was intended to have a supersonic capability on the deck, but this requirement was lowered to Mach .85 to allow the use of lower-cost aluminium structures in place of the titanium that would otherwise be necessary.
One of the principal weapons of the B-1A was to have been the AGM-69B SRAM-B. This improved missile was to have a more powerful motor and a new W80 warhead in place of the AGM-69A’s W69. The new W77 gravity bomb was also being developed for use by the B-1A, and the aircraft would also be suitable as a carrier for the new Air Launched Cruise Missile. The B-1A had three weapons bays with rotary launchers, and production aircraft would have had the capability to carry ordnance on two external pylons.
Procurement plans for the B-1A called for the purchase of no fewer than 240 aircraft, to be put into service by the early 1980s. Although small compared to the bomber programs of the 1940s and 1950s, this would nonetheless allow for a roughly one-for-one replacement of the newest B-52 models with an aircraft at least twice as effective.
Rockwell’s Plant 42 at Palmdale, California was where the B-1s were assembled, with roll out of the first prototype taking place in October 1974. Originally, there were to be six flight test aircraft, but defense cutbacks later reduced this figure to four. The first flight of a B-1 occurred on 22 December 1974, and by March 1976 three aircraft were flying.
SAC’s plans were derailed in June 1977, when President Jimmy Carter announced that procurement of the B-1 would not go forward. Carter, who had never been a proponent of the costly program, believed that the AGM-86 ALCM would keep the B-52 viable until the Advanced Technology Bomber became available in the 1980s. Construction of the incomplete fourth prototype was allowed to proceed; this aircraft, 76-0174, flew in February 1979, and was distinguished externally by the Cross Eye ECM system, with its large dorsal fairing. This aircraft also lacked the escape capsule of the earlier prototypes, having conventional (and less heavy) ACES II ejection seats. Cross Eye was later removed.
Following their use as B-1B flight test articles, two of the three surviving B-1As became museum articles, while the third was dismantled and used as an electromagnetic testbed by the Rome Air Development Center.
B-1A at the Air Force Museum, summer of 1988. Note the pointed tailcone as opposed to the more rounded unit on the B-1B.
“Potential AMSA Design Illustrated” Aviation Week & Space Technology September 16, 1968 p.34 1 illustration
“B-1 Design Has Forward Fins” Aviation Week & Space Technology May 4, 1970 p.53
Photo: “B-1 Radar Contender Tested on KC-135” Aviation Week & Space Technology February 1, 1971 p.51
Cecil Brownlow “Major Incentives Offered for B-1” Aviation Week & Space Technology June 15, 1970 p.12-13 1 illustration
“B-1 Armament Already Under Study” Aviation Week & Space Technology June 15, 1970 p.13
Michael L. Yaffee “GE Ships Final Engine for Flight-Test B-1” Aviation Week & Space Technology May 27, 1974 p.45-50 5 photos 2 illustrations
Donald E. Fink “B-1 Tests Aim to Show Mission Capability” Aviation Week & Space Technology June 3, 1974 p.48-52
“B-1 First Flight to Evaluate Systems” Aviation Week & Space Technology June 3, 1974 p.51
“Air Force Seeks to Avoid Break in B-1” Aviation Week & Space Technology July 15, 1974 p.117-122 3 photos
Photo: “B-1 prototype rolls out” Aviation Week & Space Technology November 4, 1974 front cover
“First B-1 Bomber Prototype Rolls Out” Aviation Week & Space Technology November 4, 1974 p.14-15 3 photos
“B-1 Completes Two Major Test Milestones” Aviation Week & Space Technology March 24, 1975 p.19
Photo: “B-1 Continues Test Program” Aviation Week & Space Technology April 14, 1975 p.17
“B-1 Completing Flutter Tests Prior to Supersonic Evaluation” Aviation Week & Space Technology June 9, 1975 p.24
“USAF Cuts B-1 Maximum Speed” Aviation Week & Space Technology June 16, 1975 p.18
“B-1 Antenna, Radome Tests Near End” Aviation Week & Space Technology July 14, 1975 p.51-55 5 photos
Donald E. Fink “Work Begins on Fourth B-1 Test Aircraft” Aviation Week & Space Technology August 25, 1975 p.16-18 3 photos
Donald E. Fink “Rockwell Gears for B-1 Production” Aviation Week & Space Technology December 6, 1976 p.13-14 1 photo
Cecil Brownlow “B-1 Production Plan Approved” Aviation Week & Space Technology December 6, 1976 p.12
Benjamin M. Elson “Smooth B-1 Avionics Transition Sought” Aviation Week & Space Technology April 25, 1977 p.86-91
“Carter Blocks Production of B-1” Aviation Week & Space Technology July 4, 1977 p.14-16
Donald E. Fink “Rockwell Seeks Funding To Complete Two B-1s” Aviation Week & Space Technology September 26, 1977 p.20-21
Photo of the third B-1A launching an AGM-69 SRAM Aviation Week & Space Technology November 21, 1979 p.15
Graham Wilmer “From B-1 to LRCA” Air International July 1982 includes several color shots of the camouflaged fourth prototype
The Encyclopedia of World Air Power Bill Gunston, editor 1980 p.304: B-1A 3-view
Michael J.H. Taylor Warbirds Illustrated No. 30 Strategic Bombers 1945-1985 p.2-3: Photo of the second B-1A, fitted out as a partial B-1B prototype, seen taking off.
Military Aircraft of the 1970s by Gerry Manning p.119: photo of B-1A 74-0159