The X-15 hypersonic research airplane (see Fig. 5.92) set the altitude record for airplane...

The X-15 hypersonic research airplane (see Fig. 5.92) set the altitude record for airplanes on August 22, 1963, when test pilot Joseph Walker achieved 354,200 ft. What is the acceleration of gravity at this altitude? How much does it differ from that at sea level?

Fig. 5.92 The North American X-15, the first manned hypersonic airplane. (Source: U.S. Air Force.)