A pad abort test is a kind of test of a launch escape system which conducted by setting the system along with the spacecraft still on the ground and let the system activate to carry the spacecraft flying away, then separate in the air and make the spacecraft land safely. The purpose of the test is to determine how well the system could get the crew of a spacecraft to safety in an emergency on the launch pad. As the spacecraft is set still on the ground, the test is also called "zero-altitude abort test" in against "high-altitude abort test".