THE development of a commercially profitable supersonic transport is a very difficult and complex undertaking. I believe that this country must take, in the words of Senator Monroney, "time for deliberate, proven development" and time to make certain that this will be the best supersonic in the world's airways.
Note: The statement was made public as part of a White House release which noted that the President had that day directed the Administrator of the Federal Aviation Agency to extend the current contracts of the engine and airframe manufacturers so that they could continue to study the problems associated with a commercial supersonic transport. The release also noted that the President's Advisory Committee on Supersonic Transport was expected to make recommendations early in 1965, following completion of economic studies by the Department of Commerce and of studies on sonic boom phenomena by the National Academy of Sciences.
See also Items 294 [5] and 355.
Lyndon B. Johnson, Statement by the President on the Supersonic Transport Program. Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/241442