James E. Webb
Cobb lobbied, along with other Mercury 13 participants, including Jane Briggs Hart, to be allowed to train alongside the men. However, at the time NASA requirements for entry into the astronaut program were that the applicant be a military test pilot, experienced at high speed military test flying, and have an engineering background enabling them to take over controls in the event it became necessary. Since all military test pilots were men at the time, this effectively excluded women. Liz Carpenter, the Executive Assistant to Vice President Lyndon Johnson, drafted a letter to NASA administrator James E. Webb questioning these requirements, but Johnson did not send the letter, instead writing across it: "Let's stop this now!"