Boeing and Aerojet Rocketdyne have begun a series of developmental hot-fire tests with two launch abort engines similar to the ones that will be part of Boeing’s CST-100 Starliner service module, in the Mojave Desert in California. The engines, designed to maximize thrust build-up, while minimizing overshoot during start up, will be fired between half a second and 3 seconds each during the test campaign. If the Starliner’s four launch abort engines were used during an abort scenario, they would fire between 3 and 5.5. seconds, with enough thrust to get the spacecraft and its crew away from the rocket, before splashing down in the ocean under parachutes.