Boeing's Starliner Completes Major Propulsion Test

Engineers at Boeing have completed the hot fire test on a flight-like model of the Starliner crew capsule, clearing a major hurdle before a pad abort test and a demonstration flight to the International Space Station later this summer, Boeing announced on Friday.

Boeing's CST-100 Starliner. Credit: NASA/Boeing

The successful hot fire test of the service module at NASA's White Sands Test Facility in New Mexico wraps up a key phase of Starliner's development. During an earlier round of service module hot fire test last June, the valves in the craft's abort engines failed to fully close after a brief burn, resulting in a propellant leak on the test stand at White Sands, which delayed Boeing's Starliner demonstration flight for months.

Boeing halted propulsion testing after the accident, and engineers implemented hardware and software fixes to resolve the valve problem, according to remarks last fall by Chris Ferguson, a Boeing test pilot and former NASA astronaut who will fly on the ship’s first piloted demonstration mission to the space station.

Boeing said in a statement that teams ran multiple tests on the service module, which will fly into space attached to the rear of the company’s CST-100 Starliner crew compartment. The service module contains the spacecraft’s thrusters for a launch abort and in-space maneuvers.

At the end of each mission, the Starliner will jettison the service module to burn up during re-entry into Earth’s atmosphere. The crew module will descend under parachutes for an airbag-cushioned landing at one of several candidate sites in the Western United States.

The service module test rig used in the recent hot fire testing included fuel and helium tanks, reaction control system, orbital maneuvering and attitude control thrusters, launch abort engines, and all necessary fuel lines and avionics, according to Boeing.

Each Starliner service module carries four launch abort engines, built by Aerojet Rocketdyne. The engines would only fire in flight in the event of a launch emergency, igniting with 40,000 pounds of thrust each for a few seconds to propel the capsule away from its rocket.