New Mars Forums

Official discussion forum of The Mars Society and MarsNews.com

You are not logged in.

Announcement

Announcement: As a reader of NewMars forum, we have opportunities for you to assist with technical discussions in several initiatives underway. NewMars needs volunteers with appropriate education, skills, talent, motivation and generosity of spirit as a highly valued member. Write to newmarsmember * gmail.com to tell us about your ability's to help contribute to NewMars and become a registered member.

#1376 2021-08-06 18:17:36

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,078

Re: Starship is Go...

Of course, but it's a fresh start like the USA was after old Europe-Africa.

kbd512 wrote:

Louis,

Interplanetary transport is a technological innovation to expand our reach into the solar system, not an escape mechanism.  Humanity's problems are caused primarily by humans, not the Earth itself.  All the problems humanity has will be brought with us, wherever we go, and anyone who thinks otherwise is beyond naive.


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

Offline

#1377 2021-08-06 18:19:44

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,078

Re: Starship is Go...

Good video from SpaceXcentric including a nice summary of recent events at Boca Chica.

https://www.youtube.com/watch?v=4EpyGUfIc3k

He's going into surgey next week for some reason, so I am sure we all wish Kevin the best.


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

Offline

#1378 2021-08-06 19:09:42

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 23,799

Re: Starship is Go...

There will be many more trials of the super bfr rocket long before any men will be riding even sub-orbit let along to full orbit. Then there is that added difficulty of how fast the next stack and fueling can happen as the waiting starship is only capable of deorbit or getting to the station and that is it. I hope others are tracking the time to assemble testing before, we see that its not short enough due to fuel on orbit boiloff...its that fuel that it must have before it can be useful to the moon or mars. The current versions can not connect to the station so that leaves only the last remaining option to sit there in orbit or go home.

The combined craft measures a towering 400 feet tall, making it the tallest rocket in history. And with the orbital launch stand that measures 75 feet, the entire system is larger than the Great Pyramid in Giza.AAN1rEg.img?h=480&w=799&m=6&q=60&o=f&l=f

A massive crane picked up Starship Serial Number 20 (SN20) and slowly lowered it on top of booster early Friday morning, after Super Heavy was brought to the launch pad at SpaceX’s site in Boca Chica, Texas on Wednesday.

One needs to remember that the Super Heavy, and starship both go through a series of pressurization and engine tests long before they are blessed for flight.

Online

#1379 2021-08-07 08:53:14

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,249

Re: Starship is Go...

Tim Dodd, the Everyday Astronaut, scored an exclusive tour of Starbase hosted by Elon Musk. It's a 3 part presentation, but here's the link to the first episode:

https://www.youtube.com/watch?v=t705r8ICkRw

Offline

#1380 2021-08-07 15:50:36

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,249

Re: Starship is Go...

Here is the link to part 2 of the Elon Musk tour of Starbase"

https://www.youtube.com/watch?v=SA8ZBJWo73E

This is truly incredible for the lovers of Raptor engines!

Offline

#1381 2021-08-07 16:07:08

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,078

Re: Starship is Go...

A week to finish off the tiles and check everything out. Three weeks for cryo pressure tests and static firing. A September launch is looking good.


SpaceNut wrote:

There will be many more trials of the super bfr rocket long before any men will be riding even sub-orbit let along to full orbit. Then there is that added difficulty of how fast the next stack and fueling can happen as the waiting starship is only capable of deorbit or getting to the station and that is it. I hope others are tracking the time to assemble testing before, we see that its not short enough due to fuel on orbit boiloff...its that fuel that it must have before it can be useful to the moon or mars. The current versions can not connect to the station so that leaves only the last remaining option to sit there in orbit or go home.

The combined craft measures a towering 400 feet tall, making it the tallest rocket in history. And with the orbital launch stand that measures 75 feet, the entire system is larger than the Great Pyramid in Giza.https://img-s-msn-com.akamaized.net/tenant/amp/entityid/AAN1rEg.img?h=480&w=799&m=6&q=60&o=f&l=f

A massive crane picked up Starship Serial Number 20 (SN20) and slowly lowered it on top of booster early Friday morning, after Super Heavy was brought to the launch pad at SpaceX’s site in Boca Chica, Texas on Wednesday.

One needs to remember that the Super Heavy, and starship both go through a series of pressurization and engine tests long before they are blessed for flight.


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

Offline

#1382 2021-08-07 16:17:01

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,078

Re: Starship is Go...

Thanks for the link OF. I saw this come up on YT and will try and view it through in the next few days.

Having watched a few mins, he makes the important point that rocket design is relatively easy, given all that has gone before, but developing the process for manufacturing the rockets is what requires much greater effort.

Musk looks like he is on the Trump diet but far more overworked and stressed out. Hope his health holds out.


Oldfart1939 wrote:

Tim Dodd, the Everyday Astronaut, scored an exclusive tour of Starbase hosted by Elon Musk. It's a 3 part presentation, but here's the link to the first episode:

https://www.youtube.com/watch?v=t705r8ICkRw


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

Offline

#1383 2021-08-07 16:27:58

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 23,799

Re: Starship is Go...

One issue is the reuse of a landed asset for refueled and set back onto the launch pad time frame is an unknown.

The building of new components takes a fair amount of time which seems hard to pin down.

Just the mating of pieces at the launch pad which seems to be in excess of a month time frame with the testing separately for each component before they can be stacked.

Online

#1384 2021-08-07 16:57:59

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,078

Re: Starship is Go...

I seem to recall Musk or someone associated with Space X referencing possibly three flights a day - so a turnaround of something like 7 hours. Sounds phenomenal, but I guess if you think of a rocket more as a glorified Jumbo Jet, then perhaps it's not so crazy.  The sort of turbulence jets experiencing on a regular basis is probably the equivalent of the stresses endured by a rocket.


SpaceNut wrote:

One issue is the reuse of a landed asset for refueled and set back onto the launch pad time frame is an unknown.

The building of new components takes a fair amount of time which seems hard to pin down.

Just the mating of pieces at the launch pad which seems to be in excess of a month time frame with the testing separately for each component before they can be stacked.


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

Offline

#1385 2021-08-07 17:38:08

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 23,799

Re: Starship is Go...

Not of the same scale but something for reasonable comparison is the Falcon 9 booster are on the order of 30 plus days.....

https://en.wikipedia.org/wiki/List_of_F … e_boosters

Online

#1386 2021-08-07 22:07:53

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,249

Re: Starship is Go...

Elon's presentation to Tim Dodd was pretty revealing about the goals for Starship Booster 4 and Starship 20; "Don't blow up and get off the ground; if the second stage doesn't make it to orbit--that's still progress."

The SpaceX dictum of design it--build it--fly it--break it--fix it and repeat the process until "it don't break no more."

Offline

#1387 2021-08-07 22:10:30

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 6,890
Website

Re: Starship is Go...

louis wrote:

A week to finish off the tiles and check everything out. Three weeks for cryo pressure tests and static firing. A September launch is looking good.

My question is how do the conduct static firing of the upper stage, Starship, while stacked? Do they intend to remove Starship to a suborbital launch platform for that test?

Offline

#1388 2021-08-07 22:22:42

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 7,970

Re: Starship is Go...

For RobertDyck re #1387

Great question ... is there a chance that was done before the stack?

It is certainly possible the engines were tested at McGregor before they were installed.  Is that sufficient?

(th)

Offline

#1389 2021-08-08 09:12:53

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 4,682
Website

Re: Starship is Go...

Louis,

Re:  your post 1367,  note that I stand by what I wrote in my post 1366.  Here is why:

Agency decisions made politically?  That’s not generally the way it works in the US.  The top appointed agency-head positions are very political,  yes,  but they usually don’t make the decisions,  except as final approvals in some cases.  The rank-and-file bureaucrats that actually do the work and create agency positions on issues,  are career civil service,  and for the most part,  value the agency mission above personal preferences. 

It’s not absolute,  of course,  but that’s the way it usually goes within most of our agencies.  The decisions are made in a process that works its way up the multiple levels of the agency.  They are not usually made by one person at all.  Because multiple people are involved,  it is much harder to abuse for political ends,  although it can be cumbersome and time-consuming.  That tradeoff has mostly worked well for us.

GW


GW Johnson
McGregor,  Texas

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

Offline

#1390 2021-08-08 09:19:27

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 4,682
Website

Re: Starship is Go...

As for the stacked Starship/Superheavy intended for the orbital test:  the environmental impact issue will have to be satisfied before a license to launch can be granted.  If that process is circumvented,  it is unlikely in the extreme that they will ever launch again from any US territory.  Given the investments made in facilities on US soil,  a conscious decision to violate the rules and launch without a license seems unlikely in the extreme. 

This looks more like testing the procedures to create the two-stage stack to me.  There is no reason at all that a Starship cannot be put on a test platform,  partially fueled,  and static-tested.  It could then be de-fueled and stacked.  The fly in that ointment is that the actual ascent engines are vacuum Raptors whose nozzles will not flow full at sea level.  Such a test had better be at most a second or two long,  lest damage occur.


GW Johnson
McGregor,  Texas

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

Offline

#1391 2021-08-08 09:39:12

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,078

Re: Starship is Go...

I don't want to make this thread political so I'll leave it there. The only thing that matters at this stage is whether FAA give the green light. As long as they do, I will be happy.  We are so close to an orbital launch. A successful orbital launch means we really on for the Mars project.

GW Johnson wrote:

Louis,

Re:  your post 1367,  note that I stand by what I wrote in my post 1366.  Here is why:

Agency decisions made politically?  That’s not generally the way it works in the US.  The top appointed agency-head positions are very political,  yes,  but they usually don’t make the decisions,  except as final approvals in some cases.  The rank-and-file bureaucrats that actually do the work and create agency positions on issues,  are career civil service,  and for the most part,  value the agency mission above personal preferences. 

It’s not absolute,  of course,  but that’s the way it usually goes within most of our agencies.  The decisions are made in a process that works its way up the multiple levels of the agency.  They are not usually made by one person at all.  Because multiple people are involved,  it is much harder to abuse for political ends,  although it can be cumbersome and time-consuming.  That tradeoff has mostly worked well for us.

GW


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

Offline

#1392 2021-08-08 09:42:40

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,078

Re: Starship is Go...

As I understand things. the environmental impact of a methane burn is a lot less than the stuff used on the Apollo mission (or was it the Space Shuttle) that used to coat everything for miles around in solid pollutants. The noise impact is obviously going to be a big one but can't we expect Musk and co. to have an innovative approach to that as well?

GW Johnson wrote:

As for the stacked Starship/Superheavy intended for the orbital test:  the environmental impact issue will have to be satisfied before a license to launch can be granted.  If that process is circumvented,  it is unlikely in the extreme that they will ever launch again from any US territory.  Given the investments made in facilities on US soil,  a conscious decision to violate the rules and launch without a license seems unlikely in the extreme. 

This looks more like testing the procedures to create the two-stage stack to me.  There is no reason at all that a Starship cannot be put on a test platform,  partially fueled,  and static-tested.  It could then be de-fueled and stacked.  The fly in that ointment is that the actual ascent engines are vacuum Raptors whose nozzles will not flow full at sea level.  Such a test had better be at most a second or two long,  lest damage occur.

Last edited by louis (2021-08-08 09:56:01)


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

Offline

#1393 2021-08-08 09:44:39

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,078

Re: Starship is Go...

The folks at NASA Spaceflight were suggesting that would be happening I believe. I don't know if that was guesswork on their part or something more. But I guess they need a fully fuelled Starship on top for a proper test of how the booster works.

RobertDyck wrote:
louis wrote:

A week to finish off the tiles and check everything out. Three weeks for cryo pressure tests and static firing. A September launch is looking good.

My question is how do the conduct static firing of the upper stage, Starship, while stacked? Do they intend to remove Starship to a suborbital launch platform for that test?


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

Offline

#1394 2021-08-08 09:48:07

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,078

Re: Starship is Go...

Yep - I've said before that I am always impressed by how if they fix a problem it seems to stay fixed. That may be because Musk brings a creative rather than bureaucratic approach to design and manufacturing development.

Oldfart1939 wrote:

Elon's presentation to Tim Dodd was pretty revealing about the goals for Starship Booster 4 and Starship 20; "Don't blow up and get off the ground; if the second stage doesn't make it to orbit--that's still progress."

The SpaceX dictum of design it--build it--fly it--break it--fix it and repeat the process until "it don't break no more."


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

Offline

#1395 2021-08-08 10:06:29

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,249

Re: Starship is Go...

They already de-stacked the upper stage. Probably for a short static fire at reduced power settings on the vacuum Raptors? Elon said that there's a huge maze of internal work remaining.
If he can get an FAA license to fly the vehicle by 1 September, he'll be very lucky.

Offline

#1396 2021-08-08 10:23:44

GW Johnson
Member
From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 4,682
Website

Re: Starship is Go...

To fire a vacuum engine at sea level,  you use full power setting to get the highest expansion pressure you can,  at the shock-separation point up in the bell.  That puts the shock-separation point as far down the bell as you can get it.  If it is too close to the throat,  you are quite likely to unchoke the throat,  which throws all your engine controls "off".  That makes a lot of damage or even an explosion likely. 

Methane-oxygen is a lot cleaner than solid composite,  for sure.  You do get some oxides of nitrogen where the slightly fuel-rich plume exterior is afterburning as it mixes with atmospheric air.  Not much.  You also get a little bit of soot from the carbon in the methane,  just very fine,  far smaller in size than what you get from kerosene.  The solid junk Louis mentioned from the shuttle SRB's is mostly aluminum oxide powder mixed with some unburned carbon soot.  It's a nuisance,  but not very dangerous. 

It's what you don't see that is dangerous.  There is hydrogen chloride (acid) vapor in the exhaust,  coming from the chlorine in the ammonium perchlorate oxidizer.  It is toxic to breathe these fumes,  and the H-Cl becomes hydrochloric acid as it mixes with atmospheric moisture.  If it were not for the particulate smoke,  you would see the condensation "smoke" that is the hydrochloric acid cloud interacting with the humidity.  The more humid it is,  the more of this you get. 

Could be worse,  though.  Could be NTO and one of the hydrazines.  Hydrazine is about like anhydrous ammonia for its toxicity danger,  which is rather high.  But NTO is far worse,  as any Titan missile crew could testify.

As an unrelated side note:  my wife is recovering very well. 

GW

Last edited by GW Johnson (2021-08-08 10:27:39)


GW Johnson
McGregor,  Texas

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

Offline

#1397 2021-08-08 17:48:04

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,078

Re: Starship is Go...

Scott Manley's video is very informative.

https://www.youtube.com/watch?v=-Lsbi-bVfk0

It appears that part of the stacking was a bit of showmanship - a lot of the rocket engines have never been tested yet so have already been taken down for individual testing and validation.

Interesting detail on the heat tiles as well.


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

Offline

#1398 2021-08-08 18:48:12

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,078

Re: Starship is Go...

One thing I've gleaned from the second Everyday Astronaut interview with Musk - he's not looking to incorporate a launch escape system for humans into Starship. So that's something that won't delay development, assuming the FAA will live with that.


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

Offline

#1399 2021-08-08 20:04:31

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 23,799

Re: Starship is Go...

One is not needed as starship can seperate from the booster and still perform a landing as you have already seen..all that is needed is the booster to stop its engines so that seperation can occur for starship....

Online

#1400 2021-08-08 21:25:56

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 6,890
Website

Re: Starship is Go...

YouTube by Marcus House
SpaceX Starship Fully Stacked for the first time, Starliner and Starlink Updates
This one points out Starship was only mounted only long enough to confirm fit and take pictures. It was then removed and rolled back to the high bay. Scott Manley's video posted by louis pointed out several engines still are white on the inside of the bell, indicating they've never been test fired. These engines have been removed. Presumably the engines not tested will be taken to McGregor for testing.

So I guess that answers my earlier question. Engines will be tested separately. Then Starship will most likely be static tested on a suborbital launch platform. Super Heavy will be static tested on the orbital launch platform. Then re-integration for launch.

Marcus also told us the payload for the first orbital test: a wheel of cheese.

Offline

Board footer

Powered by FluxBB