SpaceX Falcon 9 historic landing thread (1st landing attempt & most recent missions)

Now I have a countdown for the next 1:32:45....

Aha! Countdown timer just restarted at roughly T-90 minutes...

It appears that the clock just reset for 7:36 this evening. I guess I have time to mow the lawn...

help us George - when is it going ???

Launch postponed until tomorrow, looks like same time. Issue with upper stage engine actuator according to Musk.

Nate

mad4hws said:

Even though a lot of us dont say much, i for one can say I really really appreciate all of the backstory that you provide George. Thanks for taking the time and effort to do so. (should have said thank you sooner than now... But, thank you! )

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+1 Thanks to you George.

Just under 5 and a half hours to go! Hopefully they managed to resolve the technical issue.

This thread would be boring without George!

Thanks for the comments. After the crap that went on the last 2 weeks, and a backhanded insult from someone in charge who said I only ought to post rocket content, I haven't felt like posting any rocket content on TRF (Don't ask publicly about that, or maybe this thread could get removed). I'll consider this more "space" than "rocket"......

That said:

Launch set for today at 5:39 PM EDT.

Weather may be a problem:

New forecast issued. Weather doesn't look very cooperative, 60% chance of violation. Heavy clouds and liftoff winds being the primary concern. 24 hour delay isn't much better either, 50% chance of violation due to lightning.

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Although with long launch window and only 30 mins for propellant loading maybe SpaceX will delay loading if start of the window looks bad.

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So, if it is delayed a bit it may be delayed up to a couple of hours, or more (Launch window is 2.5 hours). Pretty aggravating the way they mishandled communicating the delay yesterday…. tune into YouTube to see a counting clock, then at zero, nothing for no reason, then mysteriously starting a new count, then later nothing again or whatever (I went out for a bike ride once I saw a report elsewhere the delay could be a couple of hours). SpaceX does not have to go with live humans on camera to at least put some text onto screen to say what’s going on…… even if they don’t have or do not want to say a detailed reason (say “technical issue with vehicle causing delay, launch window does not expire until xx:xx PM EDT", or the like). I mean, whoever turned the onscreen countdown clock on and off could have done that.

So, whenever this launch happens, the landing will be the same type as last time since the launch of a GTO satellite of this mass leaves very little fuel left. So another “hot” re-entry and 3-engine “suicide burn” landing. So this again will be a high-risk landing even though the previous one landed safely (albeit VERY toasted, some issues to address for future re-use. Some parts of the grid fins had melt damage).

It’ll be in daylight this time. Video-wise, there may only be the onboard ASDS cameras, so the acoustical vibrations of the exhaust may again cause the satellite uplink of the video signal to break up until after landing. The great video that was sent back for the CRS-8 landing, that apparently was from a NASA aircraft, but then that was a NASA payload. So that aircraft may not be out there to get video of this launch.

Welcome back, George.
This thread wasn't the same without you.

Speculation at NSF is that the weather may force them to stand down until after the holiday. I hope they're wrong.

Weather had been 40% favorable for launch today, now 60%.

Weather trending at 60% favorable for today's launch window.
2-hour window opens at 5:39pm ET, 9:39pm UTC

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Countdown continuing on the Youtube feeds. With a 2.5 hour window, if weather does not look good but if it is likely to improve they can do a hold to move to a launch time when weather would be better.

Takes about 30-35 minutes to load propellants, due to the super chilled LOX the Falcon-9 now uses. They can't sit around and wait long once the load is complete or it "warms up" too much. So that's why they load it fast and launch ASAP.

Youtube Live Feeds just came on, screensaver and music for now.

Launch in less than 29 minutes if it goes on schedule.

did it look like there was a jet trail above the rocket at t minus 2?

Launch in a few seconds!

Good liftoff.

Past Max-Q

Staging. Wow you could see the 2nd stage pitch a bit and correct itself.

Fairings separated.

WOW LIVE ONBOARD video on Falcon!!

See TECHNICAL webcast!!!

NOW have it on the hosted webcast.

Landing burn soon!

MADE IT!!!!!

THREE ASDS landings in a row! WOW!!!

They Got it!

Amazing live video from stage 1, never expected that. Looked like the first stage was moving pretty fast from left to right as it approached, but apparently not enough to throw it off!

Nate

Welcome back, George. I always appreciate your postings, be they rocketry related or on any subject.

This thread, especially, would not be the same without your detailed knowledge and insight.

Congrats yet again to SpaceX! And thanks for coming back George!

Musk: "Rocket landing speed was close to design max & used up contingency crush core, hence back & forth motion. Prob ok, but some risk of tipping."

https://twitter.com/elonmusk/status/736320322996076548

@elonmusk
Satellite deployed to 91,000 km apogee. All looks good.

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@elonmusk
Rocket landing speed was close to design max & used up contingency crush core, hence back & forth motion. Prob ok, but some risk of tipping

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Apparently the leg struts have some crushable material to absorb shock. The LEM had crushable honeycomb aluminum cores inside as shock absorbers, rather than springs or pneumatic, so apparently something like that (see link below).

https://heroicrelics.org/info/lm/landing-gear-strut-honeycomb.html

There is also speculation that the “crush core” was part of the lower section of the Falcon-9 booster itself, but that would be surprising if it was not the legs.

Update:

@elonmusk
Crush core is aluminum honeycomb for energy absorption in the telescoping actuator. Easy to replace (if Falcon makes it back to port).

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So the crush core is in the legs (well, in the diagonal strut that actuates and telescopes outwards).

Screengrab time:

Maneuvering…



Re-entry burn begun…



Re-entry heating causing a “fog” of charring stuff (paint at the least, and some ablative material around the base). The near-center of the grid fin on left showed some glowing before the camera got totally obscured. One of the hosts said that camera had a self-clearing system so that view should come back (A sacrificial clear material that could be discarded or scrolled away to allow a clean view later. NASCAR onboard cameras do that, albeit not at Mach-5 temperatures). Didn’t see that view again but perhaps it did clear but they wanted to switch to the ASDS view.



And…. after landing. The things that look like white "bags" on the deck, as though under the legs, were attached to a rail near the camera, not on the deck.

A 2:43 clip from the technical webcast, maneuvering just before the re-entry burn, thru the landing.

[video=youtube;XdtK0poWp20]https://www.youtube.com/watch?v=XdtK0poWp20[/video]

I recall someone previously posting that Space-X would quickly develop proficiency at recovering these things once they got the process down. That certainly seems to be the case. This goes a long way to quiet the naysayers and counter the armchair engineers that were second guessing if it was practical or even really possible. Once is a fluke, twice a coincidence. Three times starts to have substance, but four landings makes a pattern.

Now it needs to be shown that they can be refurbished and fly again. That means that the engines have to be good and all the propellant lines and tanks are in good shape. If that can be done, then the money will follow.

Here is a sped up version of the onboard camera during the whole re-entry until landing. Found on Elon Musk's Twitter.

[video=youtube;4jEz03Z8azc]https://www.youtube.com/watch?v=4jEz03Z8azc[/video]

I love this thread! It always reminds me of visiting the plant where they build the legs.

The F-9 booster will probably be returning to Port Canaveral tonight.

It has bene sighted far offshore, so far that curvature of the earth blocks the view of the tug, barge, and lower portion of the booster.



And YES, it is tilted. The landing was rough, stressing a leg, causing a built-in aluminum “crushable core” shock absorber to be crushed as designed, rather than allow the stress to break part of the leg structure (The Lunar Module used a crushable aluminum honeycomb inside the legs as shock absorbers, though in a bit different way).

So, it has been leaning ever since the landing. But has made it fine so far. And ought not be an issue for the crane to pick it up at dockside and lower it onto place on the pedestal assembly at the dock that holds it by the launch pad attachment hard points, not the legs.

The owners of the Port Canaveral Webcam got into a snit the last time and ended all video of any SpaceX coverage. So, unless sanity has prevailed, there probably will not be any live webcam footage of it returning to port, or anything at dockside. So, any video/photos will be by individuals or space news reporters who take pics or post videos afterwards.

Anybody know how Falcon Heavy will differ during landing?

georgegassaway said:

The owners of the Port Canaveral Webcam got into a snit the last time and ended all video of any SpaceX coverage.

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'Scuze me? A snit with who, exactly? Details if you have them, please.

John Beans said:

Anybody know how Falcon Heavy will differ during landing?

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There will be three of them

John Beans said:

Anybody know how Falcon Heavy will differ during landing?

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A google search turns up wonderful things:

[video=youtube;4Ca6x4QbpoM]https://www.youtube.com/watch?v=4Ca6x4QbpoM[/video]


Tony