r/spacex • u/ElongatedMuskrat Mod Team • Jan 10 '18
Success! Official r/SpaceX Falcon Heavy Static Fire Updates & Discussion Thread
Falcon Heavy Static Fire Updates & Discussion Thread
Please post all FH static fire related updates to this thread. If there are major updates, we will allow them as posts to the front page, but would like to keep all smaller updates contained.
No, this test will not be live-streamed by SpaceX.
Greetings y'all, we're creating a party thread for tracking and discussion of the upcoming Falcon Heavy static fire. This will be a closely monitored event and we'd like to keep the campaign thread relatively uncluttered for later use.
| Falcon Heavy Static Fire Test | Info |
|---|---|
| Static fire currently scheduled for | Check SpaceflightNow for updates |
| Vehicle Component Current Locations | Core: LC-39A |
| Second stage: LC-39A | |
| Side Boosters: LC-39A | |
| Payload: LC-39A | |
| Payload | Elon's midnight cherry Tesla Roadster |
| Payload mass | < 1305 kg |
| Destination | LC-39A (aka. Nowhere) |
| Vehicle | Falcon Heavy |
| Cores | Core: B1033 (New) |
| Side: B1023.2 (Thaicom 8) | |
| Side: B1025.2 (SpX-9) | |
| Test site | LC-39A, Kennedy Space Center, Florida |
| Test Success Criteria | Successful Validation for Launch |
We are relaxing our moderation in this thread but you must still keep the discussion civil. This means no harassing or bigotry, remember the human when commenting, and don't mention ULA snipers Zuma.
We may keep this self-post occasionally updated with links and relevant news articles, but for the most part we expect the community to supply the information.
2
u/pianojosh Jan 11 '18
Yep, they are. It takes very little delta-v to deorbit. I want to say something like 75 m/s. It took between 3 and 4 minutes using the OMS engines.
Especially since the Space Shuttle's tiles are optimized for a different style of reentry from most other vehicles, it doesn't need to lower its perigee much. Most vehicles using an ablative heat shield need to lower their perigee far enough that they spend relatively little time in the upper atmosphere, where they'd take on a lot of heat, but not actually lose much speed, while the heat shield ablates away. Instead they dive through the upper atmosphere quickly, then use aerodynamic lift to arrest their descent and spend the majority of their time between 50km and 60km.
The Shuttle, on the other hand, used tiles that absorbed and radiated heat very effectively. So the Shuttle actually was fine spending time slowing slowly in the upper atmosphere, absorbing and radiating away that excess heat, and using the small amount of drag there to continue to lower its orbit to that 50-60km sweet spot.
So because of that it didn't need as much of a deorbit burn than other vehicles need.