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Nov 07, 2024

NASA & Boeing Make Major Discoveries To Help Bring Crew Back Home On Boeing's Ship

This is not investment advice. The author has no position in any of the stocks mentioned. Wccftech.com has a disclosure and ethics policy. NASA and Boeing have made significant progress with their

This is not investment advice. The author has no position in any of the stocks mentioned. Wccftech.com has a disclosure and ethics policy.

NASA and Boeing have made significant progress with their ground tests for the Starliner spacecraft, currently docked to the International Space Station (ISS). Starliner took off on June 5th, and while the ship was initially expected to spend a week at the station, its return has been delayed because of helium leaks and thruster problems. As part of their process to understand the reasons behind the thruster anomalies, NASA and Boeing ran ground tests in White Sands.

Representatives from the agency and the company shared key learnings from the tests in a conference earlier today, which give them confidence in setting a launch date for Starliner's return.

NASA's Commercial Crew Manager Steve Stich started his opening remarks by sharing the progress of the agency and Boeing with their ground tests at White Sands. He explained that teams put "the thruster through the profile that it saw during the flight in terms of replicating the firings for the uphill phase, including the docking day where some of these thrusters failed off and then replicate the downhill phase." As part of this process, NASA and Boeing simulated the thruster firing to mimic the conditions it saw during docking to the ISS, which was the first time the thrusters lost power.

They also ran "five different downhill profiles." The last profile degraded the thruster, which provided key details similar to the degradation that the thrusters in space have experienced, including reduced thrust. NASA is now taking apart the thruster on the ground to understand the reasons behind the failure. These include analyzing the fuel and oxidizer valves, as well as a "bulge in a Teflon seal which can restrict the flow" of propellants to the thruster.

The key bit of analysis in this process is to see if "that particular seal survive the rest of the flight," explained Stich. This will determine the course of action that NASA and Boeing take when deciding to bring Starliner's crew home. Current tests show that the thruster could "survive, you know, up to five downhill legs," added Stich, with NASA's focus being to ensure that the seal remains intact throughout the rest of Starliner's journey.

NASA and Boeing ran tests before CFT on a secondary Starliner service module, and seals in this module have experienced "severe degradation from NTO vapor," according to the NASA official. NTO (nitrogen tetroxide) is the fuel for the thrusters, and teams are also working to understand this impact.

To further understand the degradation on Starliner's thrusters, NASA and Boeing will run another thruster firing over the weekend. As opposed to ground tests, this will fire the thrusters on the ship currently docked to ISS. It will fire 27 thrusters, excluding the thruster with low thrust, to ensure the "whole system performs the way we expect it, and the way it did last time we checked it," outlined Stich. NASA will run an agency review as early as late next week, after which it will decide when to bring the crew home.

According to Stich, the key parameters that NASA has to understand before it can bring the crew home are the helium leaks, leak stability and management in case they get worse, establishing an acceptable leak rate before departure, the weekend's test and understanding how the results from the ground tests might affect all thrusters on Starliner.

Boeing's Commercial Crew Manager Mark Nappi shared key details about the thruster leaks and the tests with the secondary service module. He explained that teams have "additional confidence" to undock from the station due to the tests. The thruster tests revealed that "there's some Teflon from a seal where the NTO enters the thruster, and that seal was eroded." According to Nappi, this material "lodged in a downstream filter," which "may be part of the cause of the degradation" that the crew experienced while they docked to the ISS.

According to Nappi, the "bigger" finding for the thruster anomaly involves the flow of the NTO to the thruster's injector. In this path, there is a "poppet that opens and closes and allows that NTO to go through." This poppet is similar in size to a bike tire's valve, and it has a Teflon seal that deformed because of the "heating and the natural vacuum that occurs with the thruster firing," which made it bulge out and restrict the fuel flow.

The Boeing executive believes these findings are "likely the root cause" and will lead to final fixes. Currently, Boeing is running a flow analysis with the clogged fuel filter and bulged Teflon to see if it can recreate the flight anomaly.

NASA's Stich stressed that his agency would fly the crew home on Starliner since the ship was designed to undock with crew on board. NASA is in the final stages of its flight rationale for return, and before the return, NASA and Boeing will hold more meetings, including an agency return review. The return includes crew recovery on Earth, which is crucial for NASA to test out with Starliner for the first time.

The test flight has allowed NASA to understand the integrated effect of commanding too many pulses on the thruster, having the thruster pointed towards the Sun, running additional firings and the thrusters located inside the doghouse, which acts as an insulator, according to Stich. These will lead NASA to decide whether the problem lies with the thrusters, its seals, the firing profile or other Starliner systems to solve the problem.