OrbitalHub

Wikipedia dicit:

A launch escape system (LES) or launch abort system (LAS) is a crew-safety system connected to a space capsule that can be used to quickly separate the capsule from its launch vehicle in case of an emergency requiring the abort of the launch, such as an impending explosion. The LES is typically controlled by a combination of automatic rocket failure detection, and a manual activation for the crew commander’s use. The LES may be used while the launch vehicle is still on the launch pad, or during its ascent. Such systems are usually of two types: solid-fuelled rocket or ejection seats.

A solid-fuelled rocket, mounted above the capsule on a tower, which delivers a relatively large thrust for a brief period of time to send the capsule a safe distance away from the launch vehicle, at which point the capsule’s parachute recovery system can be used for a safe landing on ground or water. The tower and rocket are jettisoned from the space vehicle in a normal flight at the point where it is either no longer needed, or cannot be effectively used to abort the flight. These have been used on the Mercury, Apollo, Soyuz, and Shenzhou capsules.

The crew are seated in seats that eject themselves (ejection seats) as used in military aircraft; each crew member returns to Earth with an individual parachute. Such systems are effective only in a limited range of altitudes and speeds. These have been used on the Vostok and Gemini capsules.

Credit: NASA’s Ames Research Center