SAC Bomber projects B-70 to B-2

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After diving into my books for a couple of weekends I have finished this chronology. I hope it would be useful for everyone.

This is all I have so more info and pics will be wellcome!!!

Antonio


The Power’s U-2 shot down in 1960 forced planners to re-examine the high-altitude bomber philosophy. B-58 and B-70 are incapable to cross the Soviet Air Defences (SAM and high altitude interceptors).
The B-70 follow-on program started in the 60’s. From 1961 different studies followed:

1961 B-70 Production cancelled but 3 XB-70 authorized as high-speed aerodynamic research planes.
1961 Subsonic Low Altitude Bomber
1962 Extended Range Strategic Aircraft
1963 Low Altitude Manned Penetrator
(350 000 pound craft armed with laydown weapons)
1963 Advanced Manned Penetrator Concepts
1-All subsonic Low altitude
2-Subsonic Low altitude Medium Supersonic High altitude
3- Subsonic Low altitude High Supersonic High altitude
4-V/STOL
1963 Advanced Manned Penetrating Strategic Systems (Optimized Subsonic Low altitude High Supersonic High altitude)
1963 GD presents to the USAF a couple of basic F-111 bomber concepts as an interine bomber before the “Penetrator” could be available
1964 XB-70A Valkyrie first flight
1965  Advanced Manned Strategic Aircraft  
1965 The USAF dedided to order an austere F-111 bomber version as FB-111A
1966  Robert McNamara had reservations about the effectiveness of a manned bomber in the “missile age”. He talks about an aircraft armed with long range missiles and the manned bomber as a supplement to the ballistic missile.
1966  McNamara supports a strategic version of the F-111 aircraft, in contrast to the AirForce, which regarded such an aircraft as an interim AMSA system. F-111G proposal was an strategic bomber version with more range, bigger bomb bay, better avionics and greater overall dimensions than FB-111A. USAF show no interest on it.
1967 AMSA becomes B-1. Beginning of contract definition
1968 FB-111A first flight. 263 aircraft ordered but President Nixon orders production cut to 76 aircraft in favour of B-1.
1969 B-1 RFP issued
1969 FB-111A enters service with SAC.
1970 Rockwell selected as B-1 System Contractor
1972 Boeing unveils MC747. This B747 derivative can act as a launch platform for the Minuteman missile. Initial design can drop 4 missiles through massive doors along the bottom of the rear fuselage. A Minuteman was succefuly fired from a C-5 Galaxy in a proof-of-concept demonstration.
1974 B-1A First Flight
1976 B-1A Production decision for 241 aircraft.
1977 B-1A Cancelled by President Carter
1977 747 missile-carrier studies were drawn up around the ALCM.
      Side-arm launchers extending plug doors
      Rotary launchers or “stack racks” in internal bomb bays
      Trapeze in the lower rear fuselage
   AMST also studied as a ALCM carrier deployed from small airfields
1977 B-52 to be armed with ALCM
1977 FB-111H Proposal. Totally new design and far more capable than F-111 precedent bomber versions
1977 Long-Range Combat Aircraft program starts as B-1A replacement. IOC not later than 1987
GD works on FB-111 derivatives
Rockwell works on B-1A derivatives (Crew escape capsule deleted,high altitude capability reduced,  Mach 2 to Mach 1 reduced max speed, fixed wing…). Even B-1A production was cancelled, prototype flight testing continued at a steady rate.
1977 After XST demonstrator shown promising performance, the kind of operational stealth aircraft had to be examinated.
   “A airplane”: scaled-up Have Blue with fewest possible changes
   “B airplane”: around the size of a FB-111 and two member crew.
   “A airplane” is selected but continued to fund Lockheed’s studies for “B airplane”
1978 Conceptual work on stealth bombers starts under codename “Sabre Penetrator”
1979 USAF conducts a Bomber Penetration Study using the B-1 prototypes with great succes
1979 Lockheed’s “B airplane” design grows in size reaching nuclear bomber capability.
The shape has evolved: curved wings and rounded edges rather than facets but surfaces are curved in one dimension rather than two and the shape still retains flat surfaces.
1979 Northrop starts working on a flying wing stealth bomber rival to Lockheed’s “B airplane”. The technology is based in BSAX Tacit Blue.Soviet Air Defence are focused on low level penetrators so an stealthy bomber flying high can reach its targets. Alternative design is a diamond-shaped aircraft based in its XST Have Blue proposal.
1979 Boeing working in a series of bomber designs
1979 Rockwell studies flying wing bomber 23,5 m span and FB-111 performance class
1979 B-52 can’t reach ALCM launch areas because the new MiG-31 can push the air battle over the Artic
1980 USAF issued its RPF for an Advanced Technology Bomber. Lockheed team with Rockwell and Northrop with Boeing.
   Senior Ice: codename for Northrop design
Senior Peg: codename for Lockheed design (to date 2004 it is still classified. It seems it was stealthier and smaller tha Northrop’s aircraft)
1981 President Reagan decided to fund a fleet of 100 Rockwell B-1B Lancer bombers derivated from B-1A design. LRCA becomes B-1B. Nevertheless this is a low-risk boost to SAC’s strenght until the ATB could be fielded.
1981 132 ATB order awarded to Northrop. Program codenamed Senior CJ. Design evolves to low altitude penetrator. It grows bigger and heavier with increased warload.
1981 SAC plans for a radical modification of its FB-111 instead of B-1B order rejected
1982 B-1A scheduled to be operational with SAC
1984 First B-1B rolled-out
1984 Rockwell proposed 100 B-1C modified with stealth technology but the offer is rejected
1986 B-1B achieved Initial Operational Capability
1987 Planned B-2A first flight
1989 B-2A Spirit first flight
1991 Planned B-2A IOC
1991 B-2A Production frozen at 16 aircraft
1992 B-2A Production brught to 21 aircraft
1997 B-2A attained IOC

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North American-Rockwell AMSA

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North America-Rockwell AMSA

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North American-Rockwell AMSA

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North American-Rockwell AMSA

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North American-Rockwell AMSA

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Rockwell B-1A mock-up

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General Dynamics AMSA

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Lockheed AMSA

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Lockheed AMSA

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Boeing MC747 ALCM carrier

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Boeing MC747 ALCM carrier

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FB-111A versus FB-111H

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General Dynamics FB-111H

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Boeing Bomber Projects 1979-1980