SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/aero-hypersonic-mach-five

At what speed does flight enter the hypersonic range?

Hypersonic flight begins at about Mach 5.

Start playing free

  1. Mach 0.5
  2. Mach 2
  3. Mach 5 ✔

Why: Mach numbers compare speed with the local speed of sound. Aircraft designed for Mach 5 or faster operate in the hypersonic range.

Huh, didn't know that: The speed of sound changes with atmospheric conditions, so Mach 5 is not one fixed miles-per-hour value everywhere.

The dad joke
Why was Mach 5 late to class? It zoomed past the school!
Like this card?
Play the game

References

Answer: Mach 5. Mach numbers compare speed with the local speed of sound. Aircraft designed for Mach 5 or faster operate in the hypersonic range.

  1. Civil Air Patrol, Journey of Flight Teacher's Guide www.gocivilairpatrol.com/media/cms/2nd_edition_Teachers_Guide_5D3166D76F9B1.pdf
    Hypersonic transports are designed to travel at Mach 5 and greater.
    Checked 2026-10-10.

Think this answer is wrong? Tap "Challenge this answer" on the card in the game and tell us why.

Test yourself in the game

Flying & DronesThe rocket-powered X-15 set a speed record of about what?Flying & DronesFlight faster than about what speed is called hypersonic?Flying & DronesNASA's X-43A set a speed record using what kind of engine?

That's stuff everyone should know.