NASA and SpaceX stand down on Dragon launch to study hydrazine issue

[Elderberry]

arsTECHNICA by Eric Berger - 6/7/2022

Misplaced hypergols are not something one messes around with.

NASA and SpaceX have delayed the launch of a Cargo Dragon spacecraft for at least a couple of weeks due to an issue during the prelaunch loading of hypergolic propellants.

The space agency had been planning to launch the spacecraft on June 12 but announced the delay in an email on Monday evening to reporters.

"During propellant loading of the Cargo Dragon spacecraft, elevated vapor readings of mono-methyl hydrazine were measured in an isolated region of the Draco thruster propulsion system," the space agency's statement said. "The propellant and oxidizer have been offloaded from that region to support further inspections and testing."

More: https://arstechnica.com/science/2022/06/nasa-delays-cargo-dragon-flight-due-to-a-propellant-issue/

[Elderberry]

Cause of Leaky SpaceX Cargo Vehicle Sourced to Faulty Inlet Joint

GIZMODO By Passant Rabie 6/14/2022

The propellant leak and ensuing investigation has resulted in a one-month delay to the CRS-25 cargo mission.

A SpaceX cargo mission to the International Space Station has been pushed back to no earlier than July 11 after teams discovered elevated vapor levels of propellant. The mission was originally scheduled for launch on June 10, but ground teams noticed a potential hydrazine leak while loading cargo.

On Monday, officials with NASA met with SpaceX to discuss the findings of an investigation into the problematic vapor leak. Following additional inspections and testing of the Dragon spacecraft, the investigators managed to identify the source of the leak as being a faulty Draco thruster valve inlet joint, which controls the flow of propellant. The Dragon spacecraft has 16 Draco thrusters that maneuver it in orbit, and each thruster has two valve inlet joints used for fuel.

“Teams will now remove the specific hardware to replace it ahead of flight,” NASA wrote. “NASA and SpaceX are now targeting no earlier than July 11 for launch of the CRS-25 cargo resupply mission.”

More: https://gizmodo.com/spacex-nasa-crew-dragon-cargo-1849058549