Here are the key project details of the XB-70 Valkyrie, one of the most ambitious aircraft programs of the Cold War:
Original (1960s) Dollars
Total program cost: $1.5 billion (USD)
Adjusted for Inflation (Today’s Dollars)
$12–14 billion USD (depending on inflation index used)
This makes the XB-70 one of the most expensive experimental aircraft programs ever, especially considering:
No production aircraft
Only one prototype survived
Prototypes & Fate
A must watch detail video below.
XB-70A #1 (AV-1)
First flight: 1964
Retired: 1969
Currently at National Museum of the USAF (Ohio)
XB-70A #2 (AV-2)
Crashed in 1966
Cause: Mid-air collision during a formation flight (pilot Joe Walker killed)
Overview
Official name: North American XB-70 Valkyrie
Manufacturer: North American Aviation
Country: United States
Role: Prototype supersonic strategic bomber
Program period: 1957–1969
Built: 2 prototypes (XB-70A)
Purpose of the Project
The XB-70 was designed to: Penetrate Soviet airspace at Mach 3+ and Fly at extreme altitude (above 70,000 ft)
Deliver nuclear weapons while outrunning interceptors and surface-to-air missiles
It was intended to replace the B-52 Stratofortress.
Key Technical Specifications
Max speed: Mach 3.1 (3,300 km/h / 2,050 mph)
Cruise speed: Mach 3
Service ceiling: 77,000 ft (23,500 m)
Range: 4,300 miles (6,900 km)
Engines:
6 × General Electric YJ93-GE-3 turbojets
Crew: 2 (pilot + co-pilot)
Innovative Technologies
Compression Lift
Used shockwaves generated at Mach 3 to increase lift efficiency
Folding wingtips (drooped down 25–65 degree) trapped shockwaves under the wings
Materials
Extensive use of stainless steel honeycomb structures
Titanium was considered but rejected due to cost and fabrication issues
Advanced Aerodynamics
Delta wing design
Canard foreplanes for stability at high speed
Armament (Planned)
Internal bomb bay for nuclear weapons
Never armed in practice (prototypes only)
Why the Program Was Cancelled
Soviet SAM advancements (e.g., SA-2 Guideline)
Shift in US strategy toward:
ICBMs
Submarine-launched ballistic missiles
Extremely high cost
Vulnerability despite speed
The role of high-altitude bombers became less viable.
Now looking back on those facts outlined above would you kill the project even before starting it? why should any body invest into such a meaning less project. Just to drop nuclear bombs with mach 3 speed? Doesn’t it look stupid… Why should anybody invest on generation ++ fighter jets. Wouldn’t it be meaningless to fly fighter missions with pilots on board? Do we need them in the plane? Same is true for many many projects run by internal teams in our companies…