A 'hot doghouse' problem is plaguing Boeing Starliner and NASA is working to fix it

Boeing Starliner astronauts Sunita Williams and Butch Wilmore are stranded in space as their spacecraft has malfunctioned. No one knows when will they return to Earth as NASA is still working to resolve the problem with the space capsule. As per the latest, the Starliner is suffering from overheating thrusters owing to a design flaw, which the space agency admitted to a few days back. The fault in the thrusters also led to the Starliner facing issues while docking with the space station. The agency has been testing out one of the spacecraft's thrusters on Earth for the past month, as per a report by Ars Technica.

A design flaw is apparently causing the propulsion devices to overheat. The Starliner has four thrusters fitted around the circumference of the rocket in propulsion pods, which NASA officials call "doghouses". NASA has been probing the issue at the White Sands, New Mexico test facility, where the engineers found that a design flaw is to blame for the overheating of the thrusters. The doghouses are creating a thermos-like insulation due to which the heat remains caught inside, causing them to overheat.

Besides the doghouse problem, the thrusters also seem to be thrusting too much.

"What we have found in this flight is we have fired the thrusters more than expected, and I would say more frequently," explained Steve Stich, NASA's commercial crew programme manager.

Stich added that they are trying to understand the heating effects of the pulses the thrusters saw and "make sure there’s no unintended consequences of those pulses".

Timeline of Boeing Starliner's journey

Boeing Starliner was initially supposed to take its first crewed journey in May, but technical issues kept delaying it until it finally took off on June 5. Sunita Williams and Butch Wilmore were supposed to be in space for a week, but the problem with the thrusters has kept them there longer. NASA says that there is no risk to the health of the two astronauts as the space station had sufficient supplies for the two Starliner crew and the seven regular crew members. The ISS crew will be rotated in August and NASA would have to get the two back before then.