“Testing discovers errors...
...but when the Crewed Dragon’s sibling - the Cargo Dragon - attaches to the hyper-expensive and manned ISS on a regular basis...
...then NASA and SpaceX have a responsibility to better communicate the state of the investigation.”
The system in question isn’t present on uncrewed Dragon capsules. It’s an emergency escape system.
Sorry for the late reply...
Yes, only Crew Dragon has the SuperDraco rocket engines, BUT both have Draco thrusters, and both Draco and SuperDraco thrusters pull on the same hypergolic fuel supply in the craft.
Hence it is not unreasonable to imagine that there are at least some shared components between Crew and Cargo variants when it comes to that hypergolic fuel supply.
Someone told me yesterday on Twitter that NASA and SpaceX had stated at a press conference for the Cargo Dragon launch a few weeks ago that they were satisfied by "working through the fault tree" that the same issue (still not truly known) that caused the explosion could not happen on Cargo Dragon. I guess that is the answer I was looking for. NASA and SpaceX really should have communicated that in a more obvious way.