History

How fast did the X-15 rocket plane fly?

4,520 mph. That is Mach 6.7, almost seven times the speed of sound, and no crewed airplane has beaten it since.

How close would your guess have been?

In the game we ask it like this: “What top speed in mph did the rocket-powered X-15 plane reach in 1967?”

Type a number — scored exactly the way a round in the game is.

The answer

4,520mph

Quest Giggle turns questions like this one into 30-second duels. Closest guess takes the round — free on iOS and Android.

2–4 player duels