In his 1986 State of the Union Address, President Ronald Reagan called for "a new Orient Express that could, by the end of the next decade, take off from Dulles Airport, accelerate up to 25 times the speed of sound, attaining low earth orbit or flying to Tokyo within two hours".

[1] Research suggested a maximum speed of Mach 8 for scramjet-based aircraft, as the vehicle would generate heat due to adiabatic compression, which would expend considerable energy.

The project showed that much of this energy could be recovered by passing hydrogen over the skin and carrying the heat into the combustion chamber: Mach 20 then seemed possible.

[2] In April 1986, McDonnell Douglas, Rockwell International, and General Dynamics were awarded contracts (each no more than $35 M) to develop technology for a hypersonic air-breathing SSTO vehicle/airframe.

[2] In 1990, the companies joined under the direction of Rockwell International to develop the craft, to deal with the technical and budgetary obstacles.

The demands of being a human-rated vehicle, with instrumentation, environmental control systems and safety equipment, made the X-30 larger, heavier, and more expensive than required for a technology demonstrator.

[citation needed] Temperatures on the airframe were expected to be 980 °C (1,800 °F) over a large part of the surface, with maxima of more than 1,650 °C (3,000 °F) on the leading edges and portions of the engine.

Titanium matrix composites were used by McDonnell Douglas to create a representative fuselage section called "Task D".