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#326 2019-09-07 22:03:16

Oldfart1939
Member
Registered: 2016-11-26
Posts: 1,719

Re: Starship is Go...

Another thing I like about Elon--no lack of ambition! He thinks BIG!

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#327 2019-09-08 08:35:19

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 16,181

Re: Starship is Go...

The flight rate I think is risky for a recycled starship at 24 lauches per year.
Current rocket configuration they are near or closing in on the 20 a year but thats with a fairly well tested ship design.
Size or scale of a falcon dragon combinations is tiny in comparision.

SpaceX Starship Rate of Progress Four Times Faster than the Reusable Falcon 9

Screen-Shot-2019-03-19-at-10.51.03-AM-730x430.jpg

Screen-Shot-2019-03-19-at-10.51.12-AM.jpg]

Screen-Shot-2019-01-10-at-8.52.13-AM-1024x839.png

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#328 2019-09-08 09:30:57

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,924

Re: Starship is Go...

Isn't the idea of the Starship that is replaces everything = Falcon 9 and Falcon 9H and Crew Dragon.

On that basis we should expect that rate of launch I would think. A Mars Mission will need something like 36 launches over 2.5 years alone.


SpaceNut wrote:

The flight rate I think is risky for a recycled starship at 24 lauches per year.
Current rocket configuration they are near or closing in on the 20 a year but thats with a fairly well tested ship design.
Size or scale of a falcon dragon combinations is tiny in comparision.

SpaceX Starship Rate of Progress Four Times Faster than the Reusable Falcon 9

https://www.nextbigfuture.com/wp-conten … 30x430.jpg

https://www.nextbigfuture.com/wp-conten … 12-AM.jpg]

https://www.nextbigfuture.com/wp-conten … 24x839.png


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#329 2019-09-08 15:47:15

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 16,181

Re: Starship is Go...

Not true as the capacity is not needed for all mission types plus its empty of fuel so it can do nothing else once in orbit when its got all of its payload onboard.

Boiloff over time is the issue since a launch window for mars is just 1 plus or minus of the critical day...for departure.
Sure the unmanned crafts are not an issue but the ones with the crew would be as you are in orbit all that time waiting for all fuel and cargo ships to get ready.

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#330 2019-09-08 17:20:09

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,924

Re: Starship is Go...

Nice pic showing the developing Starship.  I was able to enlarge the pic and you really get a sense of scale when you do! A recent shot I believe...


https://i.redd.it/96lkghgxkel31.jpg

H/T to

https://www.reddit.com/r/SpaceXLounge/


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#331 2019-09-12 17:04:18

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,924

Re: Starship is Go...

The rocketeers among you may enjoy this:

Speculative visualisation of the Florida and Texas Starships -

https://www.reddit.com/r/SpaceXLounge/c … s_version/


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#332 2019-09-16 14:28:22

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,924

Re: Starship is Go...

Felix seems to have his finger on the pulse:

https://www.youtube.com/watch?v=FKEpJBChBeM

Strong progress on all fronts would be my summary!

Last edited by louis (2019-09-16 14:28:47)


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#333 2019-09-17 17:10:34

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,924

Re: Starship is Go...

Great vid from LabPadre - really gives a good idea of the frenetic pace of activity at Boca Chica...I'm starting to be a a 2024 believer again!

https://www.youtube.com/watch?v=66U56mp5Cg0

I think Musk is really going for goal! Will be of huge interest to see what he says, if anything, about the 2024 timeline.

There is still a path to 2024 if all goes well, is my view. Space X clearly aren't messing around - which I presume is why we are seeing this external build of prototypes.

If they can go orbital by early 2020, it's still game on.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#334 2019-09-18 05:00:54

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,924

Re: Starship is Go...

A good video from "AMTDX" (first time I've come across them) setting out clearly where we are on the Starship:

https://www.youtube.com/watch?v=9G6992_MaTQ

The video notes Space X's impressive pace in putting together their Starship prototypes and lauds their "rapid innovation".

Space X do seem to be making very rapid progress. Let's hope they can continue this rapid pace so a Starship is in orbit by early 2020!


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#335 2019-09-18 13:13:54

tahanson43206
Member
Registered: 2018-04-27
Posts: 1,072

Re: Starship is Go...

For Louis re #334 ...

Thanks! (th)

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#336 2019-09-18 14:32:05

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,924

Re: Starship is Go...

Nice pic from Elon (taken from within the Boca Chica big tent):

https://twitter.com/elonmusk/status/1173872132880662528

Last edited by louis (2019-09-18 14:32:32)


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#337 2019-09-18 17:45:11

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 16,181

Re: Starship is Go...

Funny that even his twitter page gets spammed...

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#338 2019-09-19 12:41:42

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,924

Re: Starship is Go...

It's Felix time!

https://www.youtube.com/watch?v=mWzT-Ob3RN0

Work continuing at "extreme pace" at Boca Chica. Great to hear!


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#339 2019-09-22 16:53:29

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 16,181

Re: Starship is Go...

Not a video....Elon Musk tweets a sneak peek at his vision for SpaceX’s Starship mega-rocket

190922-starship2-630x627.jpg

Starship Mk1, which looks like a silvery silo equipped with rocket fins as it sits at SpaceX’s Boca Chica facility in South Texas. The 30-foot-wide, roughly 150-foot-tall prototype — and a similar Mk2 structure taking shape at SpaceX’s site in Florida — are meant to blaze a trail for an even bigger two-stage rocket, with the pointy-ended Starship sitting atop a Super Heavy first-stage booster.

Nose tip has forward movable fins, cold gas attitude control thrusters, header tanks for landing, composite pressure vessels, several large batteries, etc. Placed up there to balance high mass of Raptors & rear fins at the bottom.

Seems there is quite a bit of disent on 2 or 3 fins for stability...

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#340 2019-09-22 17:03:09

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,653
Website

Re: Starship is Go...

I have already said on these forums that the final product for "Starship" after testing will look little like the concepts advanced before testing.  That's just the facts of life testing flying machines.

And there's a lot more to testing than just getting off the ground.  This thing must be capable of reaching LEO and returning intact,  just to fulfill its primary function.  To leave LEO,  it must survive very much more demanding entry heating environments.  By that time it WILL NOT be a bare metal airframe!  Trust me,  I know what I am talking about!

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#341 2019-09-22 17:53:51

Oldfart1939
Member
Registered: 2016-11-26
Posts: 1,719

Re: Starship is Go...

Another thing that needs addressed: stability of vehicle while landing in rough terrain. The internal landing legs won't be same as the final vehicle. External legs, vis a vis Falcon 9 will be required, otherwise a big junk pile on it's side somewhere where it's impossible to fix!

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#342 2019-09-22 18:02:34

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 16,181

Re: Starship is Go...

Which is one more reason the winged thing does not make sense even for mars.
The evidence is in with the drill from insight that we can not predic the underneath ground holding capability.
GW has run the size of the pads and even the leg spread distance for a tall ship and BFR does not show its capability for landing until a surface is prepared for it.

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#343 2019-09-22 18:26:19

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,924

Re: Starship is Go...

I thought they are fins not wings - for stabilising on entry adjustments. Isn't the issue with the Starship flying at much higher speeds than the Falcon 9 ever has? I think it's something to do with that.


SpaceNut wrote:

Which is one more reason the winged thing does not make sense even for mars.
The evidence is in with the drill from insight that we can not predic the underneath ground holding capability.
GW has run the size of the pads and even the leg spread distance for a tall ship and BFR does not show its capability for landing until a surface is prepared for it.

Last edited by louis (2019-09-22 18:30:48)


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#344 2019-09-22 18:51:17

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 16,181

Re: Starship is Go...

The Falcon 9 rocket has small, foldable heat-resistant wings called grid fins. But the location says more to what they are intended to do...
The fins on the upper nose of the BFR are for guidance as they move but the lower do not move and are wings simular to the effects of a badmitten birdy or shuttlecock... for how it flys through the atmosphere.

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#345 2019-09-23 03:18:58

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,924

Re: Starship is Go...

My understanding is that wings in atmospheric flight give lift but fins don't.  I don't think the Falcon 9 attachments are in any sense wings. My understanding about the nose cone fins on the Starship is that they are supposed to fine tune the stability given by the bigger, lower fins. Again, I haven't noticed any mention of them being wings (ie given lift during descent, like the old Space Shuttle).


SpaceNut wrote:

The Falcon 9 rocket has small, foldable heat-resistant wings called grid fins. But the location says more to what they are intended to do...
The fins on the upper nose of the BFR are for guidance as they move but the lower do not move and are wings simular to the effects of a badmitten birdy or shuttlecock... for how it flys through the atmosphere.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#346 2019-09-23 08:23:40

Oldfart1939
Member
Registered: 2016-11-26
Posts: 1,719

Re: Starship is Go...

An update appeared today on Teslarati: all 3 Raptor engines installed! The nose cone has been undergoing lots of work internally while still on the ground, and is scheduled to be mounted on the vehicle Wednesday. The rocket should be completed by Saturday 28 September, just in time for Elon's scheduled presentation at Boca Chica.

Here's a link to a presentation by Kevin at Spacexcentric: https://www.youtube.com/watch?v=FujAJG6K68A

Last edited by Oldfart1939 (2019-09-23 08:26:05)

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#347 2019-09-23 10:53:32

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,924

Re: Starship is Go...

Here's more on fins and wings...or fins that go bump in the flight...

https://www.youtube.com/watch?v=FujAJG6K68A


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#348 2019-09-23 10:55:11

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,924

Re: Starship is Go...

Sorry OF - didn't realise I was reposting the same video link as you...

Oldfart1939 wrote:

An update appeared today on Teslarati: all 3 Raptor engines installed! The nose cone has been undergoing lots of work internally while still on the ground, and is scheduled to be mounted on the vehicle Wednesday. The rocket should be completed by Saturday 28 September, just in time for Elon's scheduled presentation at Boca Chica.

Here's a link to a presentation by Kevin at Spacexcentric: https://www.youtube.com/watch?v=FujAJG6K68A


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#349 2019-09-23 11:59:03

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,653
Website

Re: Starship is Go...

Fixed fins generate lift,  in the form of a corrective force that reduces a yaw or pitch motion.  Same thing happens with the tail feathers on an arrow. 

In one version of the "Starship",  there are 3 tail fins,  and two canard fins near the nose.  Two of the tail fins are hinged to rotate way more streamline to the cross-flow during entry.  That reduces their corrective force effect,  which would act to pitch the nose back straight into the slipstream. 

The canards aren't hinged to fold like that,  instead they are pivoted to change their air bite angle relative to body centerline axis.  This is exactly how the design achieves fine pitch angle control. 

It is after the thing pitches up to tail first for the touchdown,  that the folded tail fins unfold to become the tripod landing leg set.  At the time Musk presented that design concept,  he was emphasizing that the fins were less about being aerodynamically-stabilizing fins,  and more about being landing legs. That's also part of why two got hinged to fold up out of the entry slipstream.

This thing doesn't enter the atmosphere nose first,  and it doesn't enter dead broadside,  either.  It comes back at strong pitch angle to the relative wind,  roughly the same way the space shuttle did.  About 30-40 degrees pitched,  if I had to guess a number.  Too little,  and your windows get fried by the hot slipstream.  Too much,  and you decelerate too fast and get crushed by the air loads. Remember,  you are way hypersonic for entry.  And the air load wind pressures are proportional to velocity squared!  Only linearly proportional to density.

Bear in mind that as they do their testing with these initial prototypes,  the basic design WILL INEVITABLY change.  That is just the nature of experimental flight vehicle work,  which this is.

GW

Last edited by GW Johnson (2019-09-23 12:03:39)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#350 2019-09-23 13:23:20

louis
Member
From: UK
Registered: 2008-03-24
Posts: 4,924

Re: Starship is Go...

It's Felix time again!

Full of interesting observations as always...

https://www.youtube.com/watch?v=kpy0_2yJySc


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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