Question

What is the Mach number of Hypersonic Aircraft?

1. <0.8
2. 1.2 to 1.5
3. 0.8 to 1.2
4. 5 to 10

Answer 1

Correct Answer - Option 4 : 5 to 10

The correct option is 5 to 10.

The Mach number is the ratio of the speed of the aircraft to the speed of sound. 

• Flight that is faster than Mach 5 is known as Hypersonic.
• Flight that is faster than Mach 1 is supersonic. Supersonic includes speeds up to five times faster than the speed of sound, or Mach 5.
• Subsonic flights have Mach number less than 0.8.