The X-15 was not the first rocket-powered aircraft, but it is probably the best one ever built and flown. Before the first X-15 flew in the late 1950s, the fastest speed aircraft were Mach 3. The X-1
The United States Air Force and NASA developed the X-15 to better understand the flight in extreme conditions, including re-entry into the earth's atmosphere. More than half a century later, the exclusive airplane still holds the world record for piloted, powered aircraft after William Knight flew a vehicle at Mach 6.70 in 1967.
The X-15 is proud of its exceptional club pilots – only about a dozen aviators can claim to have flown the aircraft, which made a total of 199 flights. (They were all men, considering the era.) Before landing on the moon, Neil Armstrong flew seven X-15 missions between 1960 and 1962. The movie The First Man depicts one of these flights alive.  Another X-15 pilot, Joe Engle, also went on to a distinguished career at NASA. Planned to land on the moon during Apollo 17, along with Eugene Chernan, Engel embarks on this mission for political reasons, so that scientist Harrison Schmidt can be added to the last Apollo mission. Later, Engle will command the second space shuttle mission.
Engle is also the last of the X-15 pilots still alive. To mark the 60th anniversary of the first ever powered X-15 flight, during which Scott Crossfield raised the aircraft to 52,000 feet on September 17, 1959, Ars spoke with Engle about flying the worst aircraft the world has ever had. knew. Spoiler alert: It was exciting .
Engle graduated from the US Air Force pilot school in 1961 and served on the Fighter Group at Edwards Air Force Base in California. Two years later, after NASA's efforts to send humans to the moon began gaining traction, Engle and many other Air Force test pilots, such as Mike Collins, applied to become an astronaut as part of the agency's third class in 1963. This summer, Engle recalled being summoned to the office of the commander of the Edwards Air Force Test Center, Major-General Irving Branch, a legendary figure who led the attacks on the Pacific during World War II. Engle tried to figure out what he might have done wrong. Brunch ordered Angle to sit when he came in. "I see you applied for the NASA astronaut program," Brunch told Engle.
The test pilot allowed this, he applied to NASA for his third class of astronauts. It seemed like the next logical step in his career, and he liked the idea of going to the moon. This does not motivate a branch. As Angel tells the story, he says Branch has withheld his application to NASA and is torn in half.
"Well, I don't think I'll just approve," Brunch said.
After this unsuccessful meeting, Engle said he spent a lot of time trying to figure out what he could do to cross the boss. Weeks later, Engle learned that one of the X-15 pilots at the base, Robert White, was spinning off the program. Engel was to be his replacement.
A year earlier, White flew the X-15 to an altitude of 95 km, passing for the first time at the threshold of a space flight aboard an experimental aircraft. This qualifies White as an astronaut. Now Angle had a very good chance of following in his footsteps.
Getting in the cockpit
After joining the X-15 exploration program, Engle flies his first free flight in October 1963. He will continue to fly a total of 16 missions over two years, reaching a maximum of 85.5 km, above the threshold of the US Air Force to be considered an "astronaut". It also reached a top speed of 5.71 Mach.
Once selected for a specific mission, Engle said the pilot would spend most of his waking hours in a simulator or with test engineers to find out what data they hoped to receive from a particular flight. They also practice a lot on Lockheed F-104 Starfighter aircraft, particularly landing them on dry lake beds near Edwards Air Force Base in the event of engine damage during mission X-15.
Engineers had two major field profiles from which they wanted to collect flight data. During one designed for high altitude, the X-15 would fall from its B-52 aircraft, fire its rocket engine, and fly upward at a step as high as 45 degrees. This would provide enough energy and an elevator to send the plane on a ballistic flight, 107 km high. During such a flight, the X-15 will collect re-entry data. The other profile, in which the X-15 launches in steps of about 30 degrees, equalized about 30 km. During these flights, engineers look for high-speed flight data or heat due to impact, as air flows around the surfaces of the X-15.
On the night before the flight, technicians would rally the X-15 on the B-52 aircraft, squeezing the fuel tanks of the aircraft and preparing it for flight. As a pilot, Engle will arrive shortly after sunrise to put on a pressure suit and ensure the integrity of his PCBs. About 45 minutes before the departure of the aircraft, he will board the cockpit of the X-15 and contact life support.
The wheels will then roll and the B-52 will take off for uneven riding to a launch site and altitude of 13.7 km. It will take a little over an hour, during which time Angle will continue to look at his cue cards. In particular, he will remember the various dry pond bark he could make if there was a defect in the engine aboard the X-15, depending on how many seconds the engine burned before it was damaged. During the rare moments of reflection at this point, he does not remember being nervous. Rather, he said, "You are thrilled to die to be able to be there."
A leaflet from the United States Air Force