Coolant Leak Delays SpaceX ISS Resupply Mission

SpaceX Falcon 9 launch
Credit: NASA file photo

SpaceX has delayed by a day the planned launch from the Kennedy Space Center of the company’s 26th NASA-contracted resupply mission to the International Space Station (ISS), to address a small leak in a thermal control system.

Launch of the Falcon 9 rocket and Dragon resupply capsule has been reset for Nov. 22 at 3:54 p.m. EST, leading to an automated docking with the station’s U.S. segment on Nov. 23 at 6:30 a.m. EST. On board is a 7,700-lb. cargo that includes two new ISS Roll Out Solar Arrays (iROSAs) to continue upgrades to the orbital science laboratory’s solar power system

Forecasters, however, are predicting only a 30% chance of favorable weather due to low clouds and rain associated with a storm system moving through the Gulf of Mexico. NASA and SpaceX are working with the 45th Weather Sqdn. at Patrick Space Force Base, Florida, and the FAA to assess possible backup launch opportunities on Nov. 26 and 27.

The launch date change was announced during a Nov. 18 pre-launch news briefing that followed a NASA Launch Readiness Review.

The additional time is needed to address a coolant leak from the Dragon capsule’s thermal-control system loops that was traced to a rubber O-ring seal that was not seated properly, Sarah Parker, SpaceX’s Dragon mission management director, told reporters.

The coolant system was drained of the fluid to replace the seal, perform a helium leak check and begin the process of restoring the coolant, Parker added.

The Dragon’s science and technology payload includes the latest in a series of experiments focused on growing food in space as a source of nutrition for astronauts assigned to long-term deep-space missions. Another project is developing diagnostic techniques for drawing blood samples from astronauts and transmitting images of them back to Earth for analysis by medical experts.

So far, ISS astronauts have installed two of six planned iROSA upgrades across the orbital lab’s long solar power truss. The two iROSAs launching aboard the latest resupply mission are slated for installation during NASA spacewalks planned for Nov. 29 and Dec. 3.

Mark Carreau

Mark is based in Houston, where he has written on aerospace for more than 25 years. While at the Houston Chronicle, he was recognized by the Rotary National Award for Space Achievement Foundation in 2006 for his professional contributions to the public understanding of America's space program through news reporting.