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Engineering

How a Ramjet Transitions from Low to Hypersonic Speeds

Quick fact

A ramjet cannot produce thrust until the vehicle is already moving at supersonic speeds—typically above Mach 2—so it must be accelerated by a rocket booster or another aircraft before it can take over and push to hypersonic speeds.

Why this is interesting

You've probably seen ramjets in hypersonic missiles, but did you know they can't even start from zero speed? So how does a ramjet go from standing still to flying at five times the speed of sound?