Remove 4 letters from this seq...Remove 4 letters from this sequence (SPEYSTTEIM.) to reveal a familiar English word.
Correct answers: 8
The first user who solved this task is Sanja Šabović.
Record altitude for X-15 rocket planeIn 1963, the X-15 rocket plane achieved a world record altitude of 354,200 feet (107,960 m, 67 miles) with U.S. Air Force pilot Joseph A. Walker, flight 91 of the series of test flights. Its internal structure of titanium was covered with a skin of Inconel X, a chrome-nickel alloy. To save fuel, the X-15 was air launched from a B-52 aircraft at about 45,000 ft. Test flights between 8 Jun 1959 and 24 Oct 1968 provided data on hypersonic air flow, aerodynamic heating, control and stability at hypersonic speeds and piloting techniques for reentry used in the development of the Mercury, Gemini, and Apollo spaceflight programs.«[Image: NASA artist's conception of the flight.]