General Curtis LeMay needed Johnson to convert the A-12 variant of the Blackbird to an extended range deep penetration bomber that the Russians could not stop.
In June 1961 after President Kennedy and Premier Khrushchev had their meeting, Kennedy was convinced that they were on the brink of World War III. In fact the two leaders had discussed it. The meeting had not gone well.
General Curtis LeMay (at the time vice chief of staff of the US Air Force) called Kelly Johnson and asked for an immediate visit. This time he was bringing his paycheck. He needed Johnson to convert the A-12 Oxcart to an extended range deep penetration bomber that the Russians could not stop. ‘He wanted our Blackbird to Nuke’em back to the Stone Age!,’ Ben Rich writes in his book Skunk Works. The Q-bay located behind the cockpits (later the ANS bay) was envisioned as the bomb bay.
He ordered 10 YF-12 interceptor’s a month! Plus a two seat version of the A-12 for the US Air Force (SR-71). The plan for the two seat version of the A-12 was to survey the damage after World War III.
He wanted the full gambit, reconnaissance, bombers, interceptors.

Ben Rich writes “for once Kelly was speechless.”
Johnson was more than happy to comply with his request, but LeMay was more interested in the XB-70 Valkyrie Mach 3 strategic bomber.
At one point General LeMay wanted to order both.
Sep. 21 was the anniversary of the maiden flight of the XB-70 that took place on Sep. 21, 1964 when North American Aviation test pilots Alvin S. White and Col Joseph F. Cotton flew the Valkyrie for the first time in a flight from Palmdale to Edwards AFB.
Eventually, the XB-70 was cancelled and although an A-12 version of a supersonic bomber was proposed it never materialized. Then the YF-12 was canceled.

The worries about World War III where subsided when the US found out, that the Russians nuclear arsenal buildup had been exaggerated and that they were not on the brink of developing a supersonic bomber. But this was the beginning and this led to the Skunk Works building 31 SR-71s.
Today the XB-70 and the YF- 12 interceptor are together forever… on display side-by-side unaware of the competition! They are at the United States National Museum of the Air Force, Wright-Patterson Air Force Base, Ohio.
Be sure to check out Linda Sheffield Miller (Col Richard (Butch) Sheffield’s daughter, Col. Sheffield was an SR-71 Reconnaissance Systems Officer) Facebook Page Habubrats for awesome Blackbird’s photos and stories.
Photo credit: CIA and U.S. Air Force
