Campbell, ever superstitious,[citation needed] chose a lucky date to hold a press conference at the Charing Cross Hotel on 7 July 1965 to announce his future record breaking plans: ...
The Americans are already making plans for such a vehicle and it would be tragic for the world image of British technology if we did not compete in this great contest and win.
Ken Norris had calculated using rocket motors would result in a vehicle with very low frontal area, greater density, and lighter weight than if he went down the jet engine route.
In Bluebird Mach 1.1 application, the combined 16,000 lbf (71 kN) thrust would be equivalent of 36,000 bhp (27,000 kW; 36,000 PS) at 840 mph (1,350 km/h).
The main structure of the car was both elegant and simple, yet it would ensure significant torsional strength and also allow separate storage of the two liquids used as the propellant.
This would provide the frame to which were attached the rocket engines, one above and one below, as well as the propellant tanks – hydrogen peroxide on top, kerosene underneath to keep two very volatile fuels apart.
[1] After Campbell's death, the project continued at a low key for some years, still involving Leo Villa, with Norris as Design Consultant from 1968-1971.