- cross-posted to:
- [email protected]
- cross-posted to:
- [email protected]
The fourth flight test of Starship could launch as soon as June 5, pending regulatory approval.
The fourth flight test turns our focus from achieving orbit to demonstrating the ability to return and reuse Starship and Super Heavy. The primary objectives will be executing a landing burn and soft splashdown in the Gulf of Mexico with the Super Heavy booster, and achieving a controlled entry of Starship.
To accomplish this, several software and hardware upgrades have been made to increase overall reliability and address lessons learned from Flight 3. The SpaceX team will also implement operational changes, including the jettison of the Super Heavy’s hot-stage following boostback to reduce booster mass for the final phase of flight.
Flight 4 will fly a similar trajectory as the previous flight test, with Starship targeted to splashdown in the Indian Ocean. This flight path does not require a deorbit burn for reentry, maximizing public safety while still providing the opportunity to meet our primary objective of a controlled Starship reentry.
I find it interesting that the hot stage jettison is after the boostback burn. That implies to me that the purpose of the jettison isn’t for weight reduction. I wonder if there are aerodynamic control reasons to jettison the hot stage.
I also wonder if the hot stage ring is expected to sustain enough damage to be a single use part anyway.
The renders for Starship V2 have a dramatically redesigned hot stage mechanism. My guess is as good as any, but it’s possible the current HSR is so bulky and has nothing in common with the future version that they feel it’s actually more representative to throw it away.
I saw a video by CSI Starbase that speculated that during IFT3 the hot stage ripped off in an uncontrolled manner due to failure of the latches holding it in place. Since the latched-on nature of the interstage is a temporary measure anyway they may have figured “who cares, we’re not trying to make this bit work so just throw it away so we can properly test the stuff we do want to do.”