Author Topic: SpaceX Falcon Landing legs - General Discussion Thread  (Read 247970 times)

Offline Lar

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Re: SpaceX Falcon Landing legs - General Discussion Thread
« Reply #620 on: 06/05/2016 01:59 pm »
The legs (and engines for that matter) are able to be refurbished in a queue, and next four go back on next up reused booster.  With a significant launch rate, I suspect that SpaceX will queue up refurb'd cores, components, etc. to keep launch tempo up instead of refurbishing the returned booster as a unit -- at least until process is mature enough for something approaching gas-n-go.

That is good guesswork, it sounds plausible to me if they are not yet done with changes to things that require disassembly anyway.
« Last Edit: 06/05/2016 01:59 pm by Lar »
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Offline AncientU

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Re: SpaceX Falcon Landing legs - General Discussion Thread
« Reply #621 on: 06/05/2016 04:26 pm »
The legs (and engines for that matter) are able to be refurbished in a queue, and next four go back on next up reused booster.  With a significant launch rate, I suspect that SpaceX will queue up refurb'd cores, components, etc. to keep launch tempo up instead of refurbishing the returned booster as a unit -- at least until process is mature enough for something approaching gas-n-go.

That is good guesswork, it sounds plausible to me if they are not yet done with changes to things that require disassembly anyway.

...and then they reassemble the launcher like Lego elements.  See, rockets are LEGOs.  ;)
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Offline Lar

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Re: SpaceX Falcon Landing legs - General Discussion Thread
« Reply #622 on: 06/05/2016 05:12 pm »
The legs (and engines for that matter) are able to be refurbished in a queue, and next four go back on next up reused booster.  With a significant launch rate, I suspect that SpaceX will queue up refurb'd cores, components, etc. to keep launch tempo up instead of refurbishing the returned booster as a unit -- at least until process is mature enough for something approaching gas-n-go.

That is good guesswork, it sounds plausible to me if they are not yet done with changes to things that require disassembly anyway.

...and then they reassemble the launcher like Lego elements.  See, rockets are LEGOs.  ;)

<stamps foot> LEGO **elements** not "LEGOs"    </stamps foot> 
I see what you did there. And no they aren't, the legs don't just snap on, you have to use pins or bolts, so more like Meccano/Erector Set stuff :)
"I think it would be great to be born on Earth and to die on Mars. Just hopefully not at the point of impact." -Elon Musk
"We're a little bit like the dog who caught the bus" - Musk after CRS-8 S1 successfully landed on ASDS OCISLY

Offline IntoTheVoid

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Re: SpaceX Falcon Landing legs - General Discussion Thread
« Reply #623 on: 06/05/2016 08:27 pm »
<stamps foot> LEGO **elements** not "LEGOs"    </stamps foot> 
I see what you did there. And no they aren't, the legs don't just snap on, you have to use pins or bolts, so more like Meccano/Erector Set stuff :)

IMHO if you must call LEGO blocks and components "LEGO elements", then you failed to properly and sufficiently enjoy your LEGOs as a child.  :'(
I suppose you never used a Band-Aid either, only a "Band-Aid brand adhesive bandage". :P

Offline nacnud

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Re: SpaceX Falcon Landing legs - General Discussion Thread
« Reply #624 on: 06/05/2016 10:02 pm »
Well I've used elastoplast to cover the holes that standing on lego has made. So many holes, it took lots of maths to count them....

PS did you know that all words are made up?
« Last Edit: 06/05/2016 10:02 pm by nacnud »

Offline Lar

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Re: SpaceX Falcon Landing legs - General Discussion Thread
« Reply #625 on: 06/06/2016 05:06 am »
<stamps foot> LEGO **elements** not "LEGOs"    </stamps foot> 
I see what you did there. And no they aren't, the legs don't just snap on, you have to use pins or bolts, so more like Meccano/Erector Set stuff :)

IMHO if you must call LEGO blocks and components "LEGO elements", then you failed to properly and sufficiently enjoy your LEGOs as a child.  :'(
Wrong. Although I enjoy them as an adult far more than ever.
Quote
I suppose you never used a Band-Aid either, only a "Band-Aid brand adhesive bandage". :P
Correct.

But let's stay on topic.
"I think it would be great to be born on Earth and to die on Mars. Just hopefully not at the point of impact." -Elon Musk
"We're a little bit like the dog who caught the bus" - Musk after CRS-8 S1 successfully landed on ASDS OCISLY

Offline whitelancer64

Do we know where the crush core is located? It seems to me the most likely location of the crush core is in the second to last portion of the extendable leg sections. The portion closest to the "foot" of the leg is much shorter than the rest of the sections.
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Offline JamesH65

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Re: SpaceX Falcon Landing legs - General Discussion Thread
« Reply #627 on: 09/13/2016 03:15 pm »
Do we know where the crush core is located? It seems to me the most likely location of the crush core is in the second to last portion of the extendable leg sections. The portion closest to the "foot" of the leg is much shorter than the rest of the sections.

Would have to be at that end, as the rest of the sections house the next section down when retracted.

Offline dorkmo

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Re: SpaceX Falcon Landing legs - General Discussion Thread
« Reply #628 on: 07/30/2018 11:04 pm »
https://cdn.teslarati.com/wp-content/uploads/2018/07/F9-B1048-recovery-details-Pauline-Acalin-11c.jpg

Quote
PART# 00059670-516 REV. B
SERIAL #13
LANDING-LEG V2
CLOCKING DEGREE 315
WO# 747400/T1

Offline wannamoonbase

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Re: SpaceX Falcon Landing legs - General Discussion Thread
« Reply #629 on: 11/28/2018 01:57 am »
I haven't been paying as close attention to the latest launches and recoveries.  But I don't think they've recovered a booster without removing the legs yet.

Any word or hint on what's up with not leaving the landing legs attached?
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Offline woods170

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Re: SpaceX Falcon Landing legs - General Discussion Thread
« Reply #630 on: 11/28/2018 06:33 am »
I haven't been paying as close attention to the latest launches and recoveries.  But I don't think they've recovered a booster without removing the legs yet.

Any word or hint on what's up with not leaving the landing legs attached?

From what I hear from sources: the new leg design was supposed to have been "fold-n-go" but SpaceX ran into trouble when they first tried this, with the new leg design, on a flown stage. The legs wouldn't properly "sit" against the core stage body when re-folded, resulting in non-latching of the legs. So, they are back to the drawing board.
For now it means that, like the original leg model, the legs will be removed before the booster stage going horizontal.

Offline HMXHMX

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Re: SpaceX Falcon Landing legs - General Discussion Thread
« Reply #631 on: 11/28/2018 11:40 pm »
I haven't been paying as close attention to the latest launches and recoveries.  But I don't think they've recovered a booster without removing the legs yet.

Any word or hint on what's up with not leaving the landing legs attached?

From what I hear from sources: the new leg design was supposed to have been "fold-n-go" but SpaceX ran into trouble when they first tried this, with the new leg design, on a flown stage. The legs wouldn't properly "sit" against the core stage body when re-folded, resulting in non-latching of the legs. So, they are back to the drawing board.
For now it means that, like the original leg model, the legs will be removed before the booster stage going horizontal.

I sympathize.  At Rotary, we spent a lot of time (and money) on the gear.  Ours operated just as SpaceX desires: fold up on the pad, deploy once for recovery (gravity down-lock) and then tow the landed vehicle using gadgets we designed (yellow dollies in photo) to lift and position the stage.  Pictures of the design below.  I show the approximate position of appropriately scaled gear on a sketch of a landed F9.  (Apologies to original author who I believe is on NSF; happy to give credit if I am advised who they were.)

We originally planned DC-X type gear (pistons) similar to what SpaceX uses, but they proved to be non-optimal.  You want to avoid big sliding pistons on a vehicle that is going to see the side and vertical loads experienced by a landing F9 stage.

Offline kdhilliard

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Re: SpaceX Falcon Landing legs - General Discussion Thread
« Reply #632 on: 12/04/2018 08:50 pm »
From the CRS-16 pre-launch press conference transcript (compliments of theinternetftw -- thanks!)
Quote
Ken Kremer, SpaceUpClose: Hi, Ken Kremer for Hans. Going back to the 24-hour recycle. What I've noticed, when you've come back to Cape Canaveral, you've had some difficulty, it seems like, with the leg retraction. I'm wondering if you could talk a little about that. They've been retracted against the side, and then they were let down flush and then they were all dissected. I thought your goal was to retract them and bring them in, and not have to disassemble them and put them back on. Some I'm wondering if you could talk a little bit about that. ...

Hans Koenigsmann, SpaceX: Yeah, on the legs. I don't have the details on why we take them off right now, if what you say-- But I can confirm folding them up, basically in the launch configuration, that is the ultimate goal. Otherwise you lose too much time, obviously. So yeah, that's the goal. I'm not sure what the current process or problem is. Sorry.

Offline cambrianera

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Re: SpaceX Falcon Landing legs - General Discussion Thread
« Reply #633 on: 12/05/2018 05:44 pm »
Every time Falcon legs are folded after landing:
- three "stay open" latches has to be unlocked,
- seven "stay close" latches has to be locked,
- one opening pusher has to be retracted and folded.
Anyone of these devices failing is a loss of the stage.
Compare it with the linear design of the ROTON legs.
While successful, I find actual design of Falcon legs really complicate and I would never reuse one without a full check.
Save me the usual dissing, full disclaimer is:
This is only my opinion!
Oh to be young again. . .

Offline JamesH65

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Re: SpaceX Falcon Landing legs - General Discussion Thread
« Reply #634 on: 12/10/2018 11:56 am »
Every time Falcon legs are folded after landing:
- three "stay open" latches has to be unlocked,
- seven "stay close" latches has to be locked,
- one opening pusher has to be retracted and folded.
Anyone of these devices failing is a loss of the stage.
Compare it with the linear design of the ROTON legs.
While successful, I find actual design of Falcon legs really complicate and I would never reuse one without a full check.
Save me the usual dissing, full disclaimer is:
This is only my opinion!

How can we compare with the Roton? You've stated what the F9 has to do, but not the Roton.

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