Live Updates: NASA's Boeing Starliner capsule returns from the International Space Station

Starliner encountered some problems on the way to the space station in June.

And Boeing and NASA have been working for weeks to understand these problems.

But what exactly does NASA fear could happen?

This is exactly what Steve Stich, the space agency’s Commercial Crew Program Manager, talked about during a press conference on August 7.

But first, here is a brief introduction to Starliner technical jargon:

Power module: This is the part of the Starliner spacecraft that has experienced helium leaks and engine problems. The module is designed to separate from the crew cabin on its return to Earth and not survive the trip home.

Dog houses: Compartments on the outside of the service module that house engines.

Reaction control system nozzles: The Starliner's service module has 28 of these thrusters (and one will likely not work at all on the return flight). The RCS thrusters are used to orient the Starliner in space. Five of them malfunctioned in June en route to the International Space Station.

Jet aircraft for orbital maneuvers and attitude control: There are 20 of these engines in the Starliner's service module. To date, none of them have malfunctioned. Each OMAC has about 17 times the thrust of an RCS jet.

“For a (safe and normal) de-orbit burn, we fire 10 OMAC engines in each of the four doghouses, and then the RCS jets are just there to maintain orientation,” Stich said.

However, Stich added, the outcome could be dire if OMAC's engines fail due to helium leaks.

“The worst case scenario would be an integrated failure mechanism between the helium leaks and the RCS engines,” Stich said. “Then you could have cases that are not easily controlled, and those are the really more stressful cases that the team is worried about.”