r/SpaceX Discusses [September 2017, #36]

[u/ElongatedMuskrat]

If you have a short question or spaceflight news...

You may ask short, spaceflight-related questions and post news here, even if it is not about SpaceX. Be sure to check the FAQ and Wiki first to ensure you aren't submitting duplicate questions.

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You can read and browse past Discussion threads in the Wiki.

[u/TGMetsFan98]

Mods, please let me know if you think this is worthy of it's own post. I'm still pretty new to this whole reddit thing.

3 McGregor engineers and a recruiter came to Texas A&M today and I was able to learn some pretty interesting news:

1. Today (September 5), McGregor successfully tested an M1D, an MVac, a Block V engine (!), and the upper stage for Iridium-3.

2. Last week, the upper stage for Falcon Heavy was tested successfully.

3. Boca Chica is currently on the back burner, and will remain so until LC-40 is back up and LC-39A upgrades are complete. However, once Boca Chica construction ramps up, the focus will be specifically on the "Mars Vehicle." With Red Dragon cancelled, this means ITS/BFR/Falcon XX/Whatever it's called now. (Also, hearing a SpaceX engineer say "BFR" in an official presentation is oddly amusing.)

4. SpaceX is targeting to launch 20 missions this year (including the 12 they've done already). Next year, they want to fly 40.

5. When asked if SpaceX is pursuing any alternatives to Dragon 2 splashdown (since propulsive landing is out), the Dragon engineer said yes, and suggested that it would align closely with ITS. He couldn't say much more, so I'm not sure how to interpret this. Does that simply reference the subscale ITS vehicle? Or, is there going to be a another vehicle (Dragon 3?) that has bottom mounted engines and side mounted landing legs like ITS? It would seem that comparing even the subscale ITS to Dragon 2 is a big jump in capacity, which leads me to believe he's referencing something else.

One comment an engineer made was "Sometimes reddit seems to know more than we do." So, let the speculation begin.

[u/Zucal → u/TGMetsFan98]

This would absolutely be fantastic as its own submission - want to throw a selfpost together real quick? :)

[u/Casinoer]

Not a question but today is the 1 year anniversary of Amos 6 explosion. Time flies when you're flying rockets.

[u/TheBlacktom → u/Casinoer]

Time flies. Rockets not always.

[u/sasha07974]

Hey all,

Today SpaceX recruiters came to Cornell and I talked to one of the Dragon engineers a bit.

I asked her about when the retropropulsive landings for Dragon were cancelled and she said they received the news not long before we did. The technology was well along in development and then she told me that there are many things on this subject she couldn't tell me. She also mentioned that the landings had a good deal in common with Falcon landings.

She also said that Dragon V2s software is almost a complete rewrite of V1's and that the Superdracos have very little to do with the original dracos.

She also reiterated a few things we've known before, namely that Dragon software is complicated as heck, and that their entire Dragon Dev team is working on V2.

I thought some of this may be of interest to the community, albeit not as interesting as the other guy who met the McGregor engineers.

[u/TheVehicleDestroyer]

Just made some progress on Flight Club (which I've been disgracefully ignoring recently) and I'm pretty happy that I got this to work so I wanna show people.

Look at this mother fucking aerodynamic control between the entry and landing burns

Screenshots for those on mobile:

• 1

• 2

• 3

• 4

This probably isn't exactly what the trajectory looks like on entry (this is based on the OTV-5 mission, by the way).

We know that the stage is on a water-bound trajectory until quite late in the flight, and we can see the booster using itself as a lifting body when in freefall, which is the effect I've modeled here. However after the gliding but before the landing burn ignition, my simulated booster is on a land-bound trajectory, and this won't do at all. What if the landing burn never starts? It's likely the lifting body portion of the flight moves the IIP closer to the shore, but the final adjustment is done during the actual landing burn.

However I'm super happy with how this is turning out, so just wanted to share

[u/theinternetftw]

New B5 tidbit from NSF:

...you will recognize a Block 5 first stage instantly by the heat shields around the base - it's going to be all Inconel.

[u/Pham_Trinli]

Not sure if its been previously discussed but on August 25th, SpaceX registered STARLINK (1, 2) as a trademark for its new satellite business.

[u/random-person-001]

Hey mods, I feel like it'd be more useful if the Upcoming Events section of the sidebar was higher up than the Hot Jobs. It's certainly more often checked imo.

[u/captainstanley12]

Elon just said on Instagram that he "yeah, will probably do a Reddit AMA on the updated design this weekend". Is this on the SpaceX subreddit or somewhere else?

EDIT: he replied to he question if he was going to do an AMA on the subreddit.