A small parachute used to slow down a space vehicle, deployed prior to the main parachute. Astronauts in NASA's Mercury, Gemini, and Apollo modules experienced a hard jolt after re-entry as the drogue parachute opened before splashdown (and a harder jolt when the main parachute was deployed). The space shuttle escape suit worn by astronauts on launch and re-entry also includes a drogue and a main parachute.