How do SpaceX and Boeing launch abort systems work?

CAPE CANAVERAL, FLORIDA — Last Saturday, SpaceX's Crew Dragon capsule exploded after suffering what the company referred to as an 'anomaly' during engine tests in Cape Canaveral, Florida. Here is how the launch abort systems work in case of emergency.

According to Space.com, crewed launch missions are usually aborted through either the 'pull' or 'push' method. The 'pull' method is the oldest abort mechanism. Capsules that use this method have rocket boosters on the tip of the capsule. These thrusters pull the capsule away from the rocket in the event of a mission abort.

Newer capsules, such as SpaceX's Crew Dragon use the 'push' mechanism. The Crew Dragon has thrusters mounted on the exterior of the capsule's wall and eight SuperDraco engines installed in the hull. These engines help 'push' the capsule away from the rocket.

According to SpaceX founder, Elon Musk, these thrusters and the parachutes installed in the Crew Dragon are designed to help secure a safe landing.

Boeing's CST-100 Starliner also uses a 'push' mechanism similar to the one on the Crew Dragon, however, their capsules are equipped with four RS-88 engines built by Aerojet Rocketdyne.