itchief
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Re: SpaceX - Tests, Launches, Developments

Tue Dec 04, 2018 1:51 pm

parapente wrote:
Great to see they aced another launch and touchdown- particularly as this booster was 'pre loved' for the third time.But yup seems like the catcher 'mit' boat just doesn't work however big you make it.Cant say they didn't try their hardest.

https://www.teslarati.com/spacex-ceo-el ... sed-catch/

But as above it looks like strategy No2 is coming into play.In many ways the whole returning of these giant fairings has been an outstanding success.This time they brought both halves back from outer space to a gentle touchdown in the sea.Thats an incredible achievement.
It also appears that they can return them accurately enough to land within a few 100 meters of the mother ship. This means it's only in the water for a very short time.It really can't be very hard to ensure that the outer shell is salt water proof.
However the inside must be harder.If they can achieve proofing the inside then clearly all is not wasted and they can simply pick them up and give them a 'wash and brush'.
In some ways ( once they achieve this) it's is the end of a chapter.Full recovery and reuse of the first stage booster and third stage fairings.
Elon has announced some time ago that they have given up on trying to recover the second stage from orbit.So the Falcon 9 development programme is now essentially complete.It will simply run as a very efficient business machine,particularly ( cross fingers) when it achieves a full NASA 'man rating' early next year.
They could do more with FH but again Elon has stated that they don't intend to ( man rate) and concentrate on the Starship programme.However it's (FH) always there If needed.
Quite how any other space organisation can compete with the efficiency of the Falcon system I do not know considering all others are expendable systems.


I have to agree with you on the water landing. Many comments on here about the bad affects of the salt water on these fairings. It does not add up that they can't be reused since the Dragon goes into the sea with much more force/heat/over all abuse and is reused.
 
parapente
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Re: SpaceX - Tests, Launches, Developments

Tue Dec 04, 2018 2:24 pm

Yup the external 'shell' must be relatively easy.I note Elon suggested even these two halves will be reused.This suggests plan B has been around a while and effectively sorted ( if these 2 are to be reused as stated).
Bad weather ( wind ,storms/seastate ) will still be an issue hence I guess the preference to land direct on board.Still better than nothing.Next west coast launch it would be nice to see the giant clamshells arriving on film.I wonder whether the present secrecy is so not to give the detailed game away exactly how they achieve this incredible feat to competitors - who would no doubt also like to reuse their fairings.
 
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casinterest
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Re: SpaceX - Tests, Launches, Developments

Tue Dec 04, 2018 6:27 pm

Apparently today's launch has been delayed due to moldy mouse food. The trials and tribulations of space travel .

Same time tomorrow.
Older than I just was ,and younger than I will soo be.
 
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JetBuddy
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Re: SpaceX - Tests, Launches, Developments

Wed Dec 05, 2018 6:30 pm

Wow, looks like the booster started swerving just before landing burn. Apparantly it landed in the ocean right outside Cape Canaveral. My guess is it detected something was wrong after it started swerving and aimed for the ocean instead of land. You could see the gridfins being turned to try to stop the motion, but it couldn't.

Either way, this is a secondary objective. Primary objective is to deliver the Dragon with payload to the ISS, and that seems to be going just fine.
 
Armodeen
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Re: SpaceX - Tests, Launches, Developments

Wed Dec 05, 2018 6:38 pm

Yep it lost rotational control and started to spin just before they killed the stream. I bet it’s ‘water landing’ wasn’t very gentle!
 
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JetBuddy
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Re: SpaceX - Tests, Launches, Developments

Wed Dec 05, 2018 7:01 pm

According to Elon Musk on Twitter, this is what happened:

"Grid fin hydraulic pump stalled, so Falcon landed just out to sea. Appears to be undamaged & is transmitting data. Recovery ship dispatched."

Scott Manley then asks him if there's only one hydraulic pump, and Musk answers:

"Pump is single string. Some landing systems are not redundant, as landing is considered ground safety critical, but not mission critical. Given this event, we will likely add a backup pump & lines."
 
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Tugger
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Re: SpaceX - Tests, Launches, Developments

Wed Dec 05, 2018 8:07 pm

JetBuddy wrote:
According to Elon Musk on Twitter, this is what happened:

"Grid fin hydraulic pump stalled, so Falcon landed just out to sea. Appears to be undamaged & is transmitting data. Recovery ship dispatched."

Scott Manley then asks him if there's only one hydraulic pump, and Musk answers:

"Pump is single string. Some landing systems are not redundant, as landing is considered ground safety critical, but not mission critical. Given this event, we will likely add a backup pump & lines."

The issue and such a change will delay its "man rating" won't it? I wonder if this means a January launch of the crew is off (it is not a "launch function" so I don't know).

Tugg
I don’t know that I am unafraid to be myself, but it is hard to be somebody else. - W. Shatner
Productivity isn’t about getting more things done, rather it’s about getting the right things done, while doing less. - M. Oshin
 
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JetBuddy
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Re: SpaceX - Tests, Launches, Developments

Wed Dec 05, 2018 8:31 pm

Tugger wrote:
JetBuddy wrote:
According to Elon Musk on Twitter, this is what happened:

"Grid fin hydraulic pump stalled, so Falcon landed just out to sea. Appears to be undamaged & is transmitting data. Recovery ship dispatched."

Scott Manley then asks him if there's only one hydraulic pump, and Musk answers:

"Pump is single string. Some landing systems are not redundant, as landing is considered ground safety critical, but not mission critical. Given this event, we will likely add a backup pump & lines."



The issue and such a change will delay its "man rating" won't it? I wonder if this means a January launch of the crew is off (it is not a "launch function" so I don't know).

Tugg


In theory it should delay it unfortunately. But I wonder if they'll let this one slide because it's related to the landing system and not the launch system. Or if they insist any modification will delay the human rating, maybe Musk will decide not to implement the change on the Block 5.
 
itchief
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Re: SpaceX - Tests, Launches, Developments

Wed Dec 05, 2018 8:38 pm

Tugger wrote:
JetBuddy wrote:
According to Elon Musk on Twitter, this is what happened:

"Grid fin hydraulic pump stalled, so Falcon landed just out to sea. Appears to be undamaged & is transmitting data. Recovery ship dispatched."

Scott Manley then asks him if there's only one hydraulic pump, and Musk answers:

"Pump is single string. Some landing systems are not redundant, as landing is considered ground safety critical, but not mission critical. Given this event, we will likely add a backup pump & lines."

The issue and such a change will delay its "man rating" won't it? I wonder if this means a January launch of the crew is off (it is not a "launch function" so I don't know).

Tugg


There is no January crew launch scheduled. SpaceX has to launch the un-manned test flight to the ISS first. How will this change the "man rating", people will not be landing with the 1st stage booster?
 
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Tugger
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Re: SpaceX - Tests, Launches, Developments

Wed Dec 05, 2018 8:59 pm

itchief wrote:
Tugger wrote:
JetBuddy wrote:
According to Elon Musk on Twitter, this is what happened:

"Grid fin hydraulic pump stalled, so Falcon landed just out to sea. Appears to be undamaged & is transmitting data. Recovery ship dispatched."

Scott Manley then asks him if there's only one hydraulic pump, and Musk answers:

"Pump is single string. Some landing systems are not redundant, as landing is considered ground safety critical, but not mission critical. Given this event, we will likely add a backup pump & lines."

The issue and such a change will delay its "man rating" won't it? I wonder if this means a January launch of the crew is off (it is not a "launch function" so I don't know).

Tugg


There is no January crew launch scheduled. SpaceX has to launch the un-manned test flight to the ISS first. How will this change the "man rating", people will not be landing with the 1st stage booster?

Sorry, yes I wasn't very clear. I know no human crew will be sent up, I meant the crew version, the "Crew Dragon".
My bad, thanks for clarifying.

Tugg
I don’t know that I am unafraid to be myself, but it is hard to be somebody else. - W. Shatner
Productivity isn’t about getting more things done, rather it’s about getting the right things done, while doing less. - M. Oshin
 
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flyingturtle
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Re: SpaceX - Tests, Launches, Developments

Thu Dec 06, 2018 12:14 am

https://www.youtube.com/watch?v=-gYDHmcCztc third-party video of the "landing". Sadly, the final seconds occur behind a shrubbery.


David
Keeping calm is terrorism against those who want to live in fear.
 
parapente
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Re: SpaceX - Tests, Launches, Developments

Thu Dec 06, 2018 9:13 am

Thanks flying turtle good piece of vid'.Looks like it was a very soft touchdown but....in the wrong place.Shame.It's got nothing to do with launches of course so should not affect this area at all.
All a learning curve,as Elon has stated perhaps it needs some level of redundancy built in.Remember BFS ( Starship) will also land vertically-but will have people on board.So getting the landing 'fool proof' is highly important.
 
parapente
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Re: SpaceX - Tests, Launches, Developments

Thu Dec 06, 2018 10:04 am

Sorry quick question.We know all the engines are test fired prior to T/O and I think also at the factory.All the electrical systems are also checked.
But are the grid fins checked and actively tested??
This is/was a brand new rocket and the gridfins appeared to malfunction immediately after deployment ( the spin started immediately).It suggests that the hydraulic pump was faulty from installation.And perhaps never robustly tested -unless installed incorrectly.
It has not been an issue before.
 
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flyingturtle
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Re: SpaceX - Tests, Launches, Developments

Thu Dec 06, 2018 1:51 pm

Another video, showing the splash-down: https://www.bbc.com/news/av/technology- ... elf-to-sea


David
Keeping calm is terrorism against those who want to live in fear.
 
GST
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Re: SpaceX - Tests, Launches, Developments

Thu Dec 06, 2018 4:40 pm

itchief wrote:
Tugger wrote:
JetBuddy wrote:
According to Elon Musk on Twitter, this is what happened:

"Grid fin hydraulic pump stalled, so Falcon landed just out to sea. Appears to be undamaged & is transmitting data. Recovery ship dispatched."

Scott Manley then asks him if there's only one hydraulic pump, and Musk answers:

"Pump is single string. Some landing systems are not redundant, as landing is considered ground safety critical, but not mission critical. Given this event, we will likely add a backup pump & lines."

The issue and such a change will delay its "man rating" won't it? I wonder if this means a January launch of the crew is off (it is not a "launch function" so I don't know).

Tugg


There is no January crew launch scheduled. SpaceX has to launch the un-manned test flight to the ISS first. How will this change the "man rating", people will not be landing with the 1st stage booster?


I don't see any reason why this needs to delay the man-rating. That requires a number (10?) of successful flights of identical boosters, so they can use boosters of the current specification for initial manned flights, and droneship the landings (weather permitting) rather than boosting back to the cape. That keeps everyone on he ground safe and they'll still get the rocket back most of the time. Simultaneously they can fly the new variant with increased grid fin system redundancy exclusively on unmanned flights until they have the requisite number of consecutive successes to man-rate the new configuration.

Yesterday's event was an excellent (and successful) test of the flight control system's handling of unexpected events and of its landing abort capability.
 
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Tugger
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Re: SpaceX - Tests, Launches, Developments

Thu Dec 06, 2018 5:14 pm

flyingturtle wrote:
Another video, showing the splash-down: https://www.bbc.com/news/av/technology- ... elf-to-sea

David

It's actually quite impressive that it almost "stood up" the landing even with the out of control rotation caused by the fin pump failure. Just watching how the systems worked to compensate real time and do a soft if failed landing.

Here is a better view of the landing: https://twitter.com/elonmusk/status/1070446975642812416

Tugg
I don’t know that I am unafraid to be myself, but it is hard to be somebody else. - W. Shatner
Productivity isn’t about getting more things done, rather it’s about getting the right things done, while doing less. - M. Oshin
 
itchief
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Re: SpaceX - Tests, Launches, Developments

Thu Dec 06, 2018 5:33 pm

Tugger wrote:
flyingturtle wrote:
Another video, showing the splash-down: https://www.bbc.com/news/av/technology- ... elf-to-sea

David

It's actually quite impressive that it almost "stood up" the landing even with the out of control rotation caused by the fin pump failure. Just watching how the systems worked to compensate real time and do a soft if failed landing.

Here is a better view of the landing: https://twitter.com/elonmusk/status/1070446975642812416

Tugg


Recovering the hardware to see what caused the failure should not be a problem. It sure did look like a good landing even though it was off target. They could alway add some floaties to the landing legs:-)
 
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casinterest
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Re: SpaceX - Tests, Launches, Developments

Thu Dec 06, 2018 6:06 pm

Pretty good explanation of what happened, and what may get done for it using Elon's tweets.

https://www.youtube.com/watch?v=Ge1_6MUWAYg

As stated in the video, an engineering opportunity to make a better rocket.
Older than I just was ,and younger than I will soo be.
 
DarkKnight5
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Re: SpaceX - Tests, Launches, Developments

Fri Dec 07, 2018 2:39 am

I’m still kind of shocked that such an important system does not have built in redundancy. I understand NASA/FAA may not have required it, but it seems it’s cheaper to have redundant hydrolics than to have to scrap a new booster after a water landing. Maybe that’s just 20/20 hindsight.
 
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Francoflier
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Re: SpaceX - Tests, Launches, Developments

Fri Dec 07, 2018 3:17 am

The next F9 booster will also end up in the drink, albeit intentionally this time, after launching the GPS III-1 mission in about 10 days' time.

No more booster landings for 2018...

I am really skeptical of Musk's claim that they might re-use B1050 after fishing it out...
I'm pretty sure the engines are toast and I would say that most of the more delicate systems in there would not have appreciated being bathed in warm saltwater for a while either. I really can't see how it would be worth refurbishing. Was he just trying to save face or to minimize the failure?

The good thing is that they can get it back intact and know exactly why it failed and how to prevent it from happening again.
I'll do my own airline. With Blackjack. And hookers. In fact, forget the airline.
 
DarkKnight5
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Re: SpaceX - Tests, Launches, Developments

Fri Dec 07, 2018 6:55 am

Francoflier wrote:
The next F9 booster will also end up in the drink, albeit intentionally this time, after launching the GPS III-1 mission in about 10 days' time.

No more booster landings for 2018...

I am really skeptical of Musk's claim that they might re-use B1050 after fishing it out...
I'm pretty sure the engines are toast and I would say that most of the more delicate systems in there would not have appreciated being bathed in warm saltwater for a while either. I really can't see how it would be worth refurbishing. Was he just trying to save face or to minimize the failure?

The good thing is that they can get it back intact and know exactly why it failed and how to prevent it from happening again.


I thought he said they “might” use it for an “internal SpaceX mission.” This to me says to things:
1) they have no clue if it will be flyable again.
2) even if it is, no customer is going to pay to use it.

So, if they use it, it will be for a test of some kind (hello crew dragon launch abort test) or for something where only their own hardware is at risk, aka Starlink.

If they can get it into a flying condition again, I would speculate they don’t try to recover it after launch and just let it sink.

Luckily, they know how to hold-down fire the whole booster so they can put it through a bunch of test burns if they need to.
 
parapente
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Re: SpaceX - Tests, Launches, Developments

Fri Dec 07, 2018 12:10 pm

Yup. They have two decent choices.
1. A refurb and use it for some kind of Spaces test.
2. Strip it and keeep/refurb all the expensive bits.Titanium grid fins and hopefully ( most of) the motor parts.No doubt many othe bits and pieces.
I am sure he would love to reply it if poss' if only to make a point (ego).
 
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Tugger
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Re: SpaceX - Tests, Launches, Developments

Fri Dec 07, 2018 2:45 pm

Another view of the water landing. https://twitter.com/elonmusk/status/107 ... 00/video/1

parapente wrote:
I am sure he would love to reply it if poss' if only to make a point (ego).

I'm pretty sure you meant "refly" (auto-incorrect to the rescue?) and if so then to me, I think the biggest thing it would prove is how actually durable the system(s) actually is. People think of space systems as big, powerful, expensive, but often fragile things. If this can successfully re-fly that would be really impressive.

It would show that just like an aircraft that suffers a crash/incident but is then repaired and returned to service. That's a big deal.

Tugg
I don’t know that I am unafraid to be myself, but it is hard to be somebody else. - W. Shatner
Productivity isn’t about getting more things done, rather it’s about getting the right things done, while doing less. - M. Oshin
 
parapente
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Re: SpaceX - Tests, Launches, Developments

Tue Dec 11, 2018 2:27 pm

Soooo the BFR is now going to be metal! I guess we all want to see and hear the new - new ,latest news - sometime in the next week or so.I note that ( from what I understand) the on again off again - now on again mini BFR ( aka F9 modified second stage) will also now fly.Perhaps.
Elon's rush runs unabated.
But just what is the rush?
I don't believe it's Mars at all.Perhaps never has been.At least not in the time frames he invents.
He is like a snake oil salesman.He makes crazy statements and all the journo's who know nothing about the space engineering and logistics simply print what pretty pictures He gives them.
Using BFR chemical rockets there is nearly no way back from Mars.
Correction one engineering mathematician calculated it would take circa 60 launches.Of course that involves in space refusing of hundreds of tonnes of cryogenically cold liquids each time.Who has ever tried - no contimplated doing this? No one.Not even in LEO let alone in Mars orbit or on the surface.Nope he just says we will make it there when we get there.Sorry that's pure bollocks.Again the maths ,100 tonnes of the stuff? Each time -Come on just stop and think - don't be 'told'.

So if not that what's it all about?
Elon Musk is a (V good) businessman ( much as he would like us to consider himself a scientist).
The answer is STARLINK .Its also the reason for the rush.

Even with the BFR it's going to take 30-40 launches to put up the required satellites.He will have the only rocket capable of launching them commercially.Perhaps except ...A man from Amazon.Who has been working on his giant rocket longer ( but just more quietly).

So Elon needs to get this giant 'satellite launcher' ( yup that's what it really is)working and working fast.And needs to perfect his comm's sat fast ( just fired the last CEO of this business) was a Microsoft man and apparently wasn't working fast enough.The guy who gets this new comms system up first will make billions $$$.
It's gonna be Elon.

Objective number 2 is probably to make the SLS redundant -God knows it costs enough.If the BFR system can be seen to work NASA ( gov't)are very likely to terminate it.Indeed NASA has already indicated they would do so -in public.They used the diplomatic word 'retire'.

After that ? The Moon - because that's what the president wants - and thus will pay for.(remember he us a businessman first and foremost).

Then,then perhaps after that he may try for a Mars shot.But he still needs to explain how astronauts are going to return ( not relying on some pie in the sky giant manufacturing and chilling/compressing factory that will be needed -that isn't there).Or even proven technically.

The key to any magician is to make you look one way when really it's all going on in the other hand.This is Musk.Someone needs to ask him some of the real questions instead of sitting there open mouthed.He will get stuck very quickly I assure you.

All this may sound harsh.Its not.The man is a genius,but he can't defy the laws of physics or the need for $ gazillions and time to achieve what his photoshop images show.
But he will (I hope) deliver us Starlink,and he may well be the guy who puts American boots on the Moon once more.Just don't hold your breath for boots on Mars!

And regarding Mars.What did the greatest -Von Braun ,think was required to get to Mars ( because he had it all planned).
First stage -The Saturn 5,not so different to the first stage BFR except that reusable.
Final stage(s) a Mars lander and ascent veichle (think Apollo).But what was in the all important middle?

A Nuclerar thermal rocket stage.Why? Because a chemical rocket simply does not have the energy density required.
By 1972 ( after 10 years development) they had one perfected,fully land tested and ready.The next stage was to use a Saturn5 to test it in space.This rocket engine could take to Mars ( fast),could slow you down into low Mars Orbit.Coukd happily wait there.Once the ascent veichle had returned and docked it still has the fuel to.
Blast you out of Mars gravity well,
Take you back to Earth ( fast -,think radiation issues).
Could slow you down to LEO.Dock with an Earth re-entry veichle and home.

Note the Russians have now stated that they are going to reactivity their Nuclear Thermal Rocket programme ( yup they had also realised it was and is the only way).Thats what they are working on right now.
Perhaps they should give Elon a call!Perhaps they already have?
 
parapente
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Re: SpaceX - Tests, Launches, Developments

Tue Dec 11, 2018 2:27 pm

Soooo the BFR is now going to be metal! I guess we all want to see and hear the new - new ,latest news - sometime in the next week or so.I note that ( from what I understand) the on again off again - now on again mini BFR ( aka F9 modified second stage) will also now fly.Perhaps.
Elon's rush runs unabated.
But just what is the rush?
I don't believe it's Mars at all.Perhaps never has been.At least not in the time frames he invents.
He is like a snake oil salesman.He makes crazy statements and all the journo's who know nothing about the space engineering and logistics simply print what pretty pictures He gives them.
Using BFR chemical rockets there is nearly no way back from Mars.
Correction one engineering mathematician calculated it would take circa 60 launches.Of course that involves in space refusing of hundreds of tonnes of cryogenically cold liquids each time.Who has ever tried - no contimplated doing this? No one.Not even in LEO let alone in Mars orbit or on the surface.Nope he just says we will make it there when we get there.Sorry that's pure bollocks.Again the maths ,100 tonnes of the stuff? Each time -Come on just stop and think - don't be 'told'.

So if not that what's it all about?
Elon Musk is a (V good) businessman ( much as he would like us to consider himself a scientist).
The answer is STARLINK .Its also the reason for the rush.

Even with the BFR it's going to take 30-40 launches to put up the required satellites.He will have the only rocket capable of launching them commercially.Perhaps except ...A man from Amazon.Who has been working on his giant rocket longer ( but just more quietly).

So Elon needs to get this giant 'satellite launcher' ( yup that's what it really is)working and working fast.And needs to perfect his comm's sat fast ( just fired the last CEO of this business) was a Microsoft man and apparently wasn't working fast enough.The guy who gets this new comms system up first will make billions $$$.
It's gonna be Elon.

Objective number 2 is probably to make the SLS redundant -God knows it costs enough.If the BFR system can be seen to work NASA ( gov't)are very likely to terminate it.Indeed NASA has already indicated they would do so -in public.They used the diplomatic word 'retire'.

After that ? The Moon - because that's what the president wants - and thus will pay for.(remember he us a businessman first and foremost).

Then,then perhaps after that he may try for a Mars shot.But he still needs to explain how astronauts are going to return ( not relying on some pie in the sky giant manufacturing and chilling/compressing factory that will be needed -that isn't there).Or even proven technically.

The key to any magician is to make you look one way when really it's all going on in the other hand.This is Musk.Someone needs to ask him some of the real questions instead of sitting there open mouthed.He will get stuck very quickly I assure you.

All this may sound harsh.Its not.The man is a genius,but he can't defy the laws of physics or the need for $ gazillions and time to achieve what his photoshop images show.
But he will (I hope) deliver us Starlink,and he may well be the guy who puts American boots on the Moon once more.Just don't hold your breath for boots on Mars!

And regarding Mars.What did the greatest -Von Braun ,think was required to get to Mars ( because he had it all planned).
First stage -The Saturn 5,not so different to the first stage BFR except that reusable.
Final stage(s) a Mars lander and ascent veichle (think Apollo).But what was in the all important middle?

A Nuclerar thermal rocket stage.Why? Because a chemical rocket simply does not have the energy density required.
By 1972 ( after 10 years development) they had one perfected,fully land tested and ready.The next stage was to use a Saturn5 to test it in space.This rocket engine could take to Mars ( fast),could slow you down into low Mars Orbit.Coukd happily wait there.Once the ascent veichle had returned and docked it still has the fuel to.
Blast you out of Mars gravity well,
Take you back to Earth ( fast -,think radiation issues).
Could slow you down to LEO.Dock with an Earth re-entry veichle and home.

Note the Russians have now stated that they are going to reactivity their Nuclear Thermal Rocket programme ( yup they had also realised it was and is the only way).Thats what they are working on right now.
Perhaps they should give Elon a call!Perhaps they already have?
 
ZaphodHarkonnen
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Re: SpaceX - Tests, Launches, Developments

Tue Dec 11, 2018 11:16 pm

DarkKnight5 wrote:
I’m still kind of shocked that such an important system does not have built in redundancy. I understand NASA/FAA may not have required it, but it seems it’s cheaper to have redundant hydrolics than to have to scrap a new booster after a water landing. Maybe that’s just 20/20 hindsight.


Such redundancy would eat into payload capacity.

The return trajectory is designed so that if something goes wrong the booster will impact well away from anything important. The final landing burn includes a translation to take the booster over the landing pad. In this case it worked entirely as designed. For this sort of thing it would make more sense to up the reliability of the failed part than duplicate it. Think of it like with planes going from 4 to 3 and then 2 engines.
 
DarkKnight5
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Re: SpaceX - Tests, Launches, Developments

Wed Dec 12, 2018 12:02 am

ZaphodHarkonnen wrote:
DarkKnight5 wrote:
I’m still kind of shocked that such an important system does not have built in redundancy. I understand NASA/FAA may not have required it, but it seems it’s cheaper to have redundant hydrolics than to have to scrap a new booster after a water landing. Maybe that’s just 20/20 hindsight.


Such redundancy would eat into payload capacity.

The return trajectory is designed so that if something goes wrong the booster will impact well away from anything important. The final landing burn includes a translation to take the booster over the landing pad. In this case it worked entirely as designed. For this sort of thing it would make more sense to up the reliability of the failed part than duplicate it. Think of it like with planes going from 4 to 3 and then 2 engines.


Yes I understand all of those points. And yet Musk himself has said they’re probably going to make it redundant. I assume in hindsight it’s an easy decision to trade a few pounds of payload to keep the Booster and engines commercially reusable rather than dropping it in the ocean, thereby protecting the business model of the company at the expense of a little performance.

Even with your airliner example, two engines are redundant. Not sure we’ll see the day when a single engine airliner is commercially flying passengers around. The grid fins had no redundancy whatsoever.
 
parapente
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Re: SpaceX - Tests, Launches, Developments

Wed Dec 12, 2018 10:24 am

Not having a go at Elon ( seems like I do though).But only the previous week he stated that the BFR ( or scale prototype) did not need to practice vertical landings as they ' had this cracked'.Hmmmm.There are and will never be any people on F9/H first stage landings.But there most certainly will on 'Starship'.So getting redundancy sorted is critical ( now) if he wants people to have any sort of confidence.
Having said that ( re above) it's probably only going to be used to put thousands of comm's sat's up for the first few years anyway.( he will refund the deposit later).But even here the economics only works if they land successfully each time.
 
DarkKnight5
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Re: SpaceX - Tests, Launches, Developments

Wed Dec 12, 2018 1:26 pm

parapente wrote:
Not having a go at Elon ( seems like I do though).But only the previous week he stated that the BFR ( or scale prototype) did not need to practice vertical landings as they ' had this cracked'.Hmmmm.There are and will never be any people on F9/H first stage landings.But there most certainly will on 'Starship'.So getting redundancy sorted is critical ( now) if he wants people to have any sort of confidence.
Having said that ( re above) it's probably only going to be used to put thousands of comm's sat's up for the first few years anyway.( he will refund the deposit later).But even here the economics only works if they land successfully each time.


As I’ve said before: that’s not what Elon said. You’re extrapolating things and making it seem like he said something he didn’t.

He said that the scale-model Starship that would launch on F9 would be intended to test aerodynamic braking on the edge of the atmosphere as that was where they need to gain experience. Since that was the purpose of the test, they didn’t need to bother propulsive landing of the test article.

Low-altitude aerodynamics are well understood as is the technique for propulsive landing. No testing required to figure out how to do that. The landing failure was the result of a hydraulic failure.

As for the actual planned testing, they will do grasshopper tests in Texas, which includes a propulsive landing for each test. As you note, people won’t be riding starship until it’s man-rated, so it will have lots of propulsive landings under its belt and redundant systems to do that safely.

I don’t know what point you’re trying to make.
 
parapente
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Re: SpaceX - Tests, Launches, Developments

Wed Dec 12, 2018 3:28 pm

Well it's not what he said actually.He said he had got the vertical landing cracked - just before a brand new booster that turns out had zero back up systems went into the drink.
But the way an F9 booster returns and lands is totally and fundamentally different.Furthermore it will never carry humans.So yes I disagree with him he should imho test the tricky manoeuvre from high speed space re- entry into the vertical landing.If he looses a scale test veichle -well bad luck.But far better than losing a whole Starship!
We/he does not know how new Glen is progressing.OK it's not 'as' big but it's big ( enough).And the SLS? Yes it's expensive - but what if it works perfectly right out of the box ( which it probably will).
 
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Nomadd
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Re: SpaceX - Tests, Launches, Developments

Wed Dec 12, 2018 5:01 pm

parapente wrote:
Well it's not what he said actually.He said he had got the vertical landing cracked - just before a brand new booster that turns out had zero back up systems went into the drink.
But the way an F9 booster returns and lands is totally and fundamentally different.Furthermore it will never carry humans.So yes I disagree with him he should imho test the tricky manoeuvre from high speed space re- entry into the vertical landing.If he looses a scale test veichle -well bad luck.But far better than losing a whole Starship!
We/he does not know how new Glen is progressing.OK it's not 'as' big but it's big ( enough).And the SLS? Yes it's expensive - but what if it works perfectly right out of the box ( which it probably will).

Testing landing on a Falcon 2nd stage with some modifications to make it act like a BFS makes little sense, would have little value and probably isn't possible. It would be a completely different ship with different engines, fuel and flight characteristics, and the engine thrust to spacecraft weight ratio would make it un-doable in any case.
 
parapente
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Re: SpaceX - Tests, Launches, Developments

Wed Dec 12, 2018 7:59 pm

Fair answer nomadd.just wished he had said that as an honest and sensible reply rather than one of his flippant so called humarisms- which turned out to be wrong anyway a few days later.But since you are no doubt right it's gonna imho make for one hairy first test flight the first time they take a Starship for LEO to land.But of course I wish them the very very best.
Lots of speculation on the net as to his 'heavy metal' comments.Once again I wish he would report in a mature fashion. Clearly there are thousands of hard working guys and girls working on this project.They don't need the CEO pissing off NASA smoking joints and making stupid price sensitive comments on Tesla.Needs to think about others. No he's not Iron Man with a hair transplant.Just a good businessman.
 
DarkKnight5
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Re: SpaceX - Tests, Launches, Developments

Wed Dec 12, 2018 9:27 pm

parapente wrote:
Fair answer nomadd.just wished he had said that as an honest and sensible reply rather than one of his flippant so called humarisms- which turned out to be wrong anyway a few days later.But since you are no doubt right it's gonna imho make for one hairy first test flight the first time they take a Starship for LEO to land.But of course I wish them the very very best.
Lots of speculation on the net as to his 'heavy metal' comments.Once again I wish he would report in a mature fashion. Clearly there are thousands of hard working guys and girls working on this project.They don't need the CEO pissing off NASA smoking joints and making stupid price sensitive comments on Tesla.Needs to think about others. No he's not Iron Man with a hair transplant.Just a good businessman.


How do you propose they test a landing from orbit without going to orbit prior testing the landing from orbit? Excluding the hop test flights and landings they’re going to do, of course.
 
maxter
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Re: SpaceX - Tests, Launches, Developments

Thu Dec 13, 2018 8:28 am

parapente, you keep stating that " you are not having a go at Elon" but your posts inevitably become critical of Musk, offer back handed complements or seem to be dismissive of SpaceX's achievements. Not exactly sure where your claim and reality intersect, certainly elusive on these pages. While I have zero claim on any scientific or engineering skills or capability, I would really like to know what your bona fides are in comparison with the achievements of Musk.
maxter
 
parapente
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Re: SpaceX - Tests, Launches, Developments

Thu Dec 13, 2018 12:27 pm

Yes it is true my attitude has changed towards Elon - but not his companies and what he has achieved with them.I think like many I was initially sucked in by the whole ' iron man' image and style of language.But now feel that his enormous ego and attitude to everybody is somewhat disturbing.
If you take him on his face value he was 'Mr Pay Pal' but he wasn't -only a small part of it and indeed was fired from it.If you take his story he founded Tesla- no he didn't be was part of a round of additional funding and got the two founders and creators out.They even had to sign a legal document allowing him to be called a 'co founder'.If you believe his interviews on Spacex he 'read a book' on rocketry and designed it.No he didn't he hired the US' most brilliant rocket engineer Tom Mueller who used to work at TRW.He designed and ran incredible rocket engines with them and then went on to do the same in a personal capacity.He is the true genius.But you would not think so listening to Elon.

Then he takes us all for fools with his pretty pictures and glib comments.There are those who have actually worked out how many BFR launches it would take to get 2 cargo rockets to Mars ; non return) and one pax one that gets back.Its over 30 launches.So why not be honest rather than these childish presentations.
BFR is about getting Starlink up first.With his competitors having no way to economically to launch.That is what the big deal really is.

Having said all that I am a space junkie.As a little child I saw the moon landings on TV So of course after all these decades I am the first to be sucked in.
 
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Nomadd
Posts: 148
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Re: SpaceX - Tests, Launches, Developments

Thu Dec 13, 2018 11:22 pm

parapente wrote:
Yes it is true my attitude has changed towards Elon - but not his companies and what he has achieved with them.I think like many I was initially sucked in by the whole ' iron man' image and style of language.But now feel that his enormous ego and attitude to everybody is somewhat disturbing.
If you take him on his face value he was 'Mr Pay Pal' but he wasn't -only a small part of it and indeed was fired from it.If you take his story he founded Tesla- no he didn't be was part of a round of additional funding and got the two founders and creators out.They even had to sign a legal document allowing him to be called a 'co founder'.If you believe his interviews on Spacex he 'read a book' on rocketry and designed it.No he didn't he hired the US' most brilliant rocket engineer Tom Mueller who used to work at TRW.He designed and ran incredible rocket engines with them and then went on to do the same in a personal capacity.He is the true genius.But you would not think so listening to Elon.

Then he takes us all for fools with his pretty pictures and glib comments.There are those who have actually worked out how many BFR launches it would take to get 2 cargo rockets to Mars ; non return) and one pax one that gets back.Its over 30 launches.So why not be honest rather than these childish presentations.
BFR is about getting Starlink up first.With his competitors having no way to economically to launch.That is what the big deal really is.

Having said all that I am a space junkie.As a little child I saw the moon landings on TV So of course after all these decades I am the first to be sucked in.

Musk built Tesla himself. about the only thing he kept from those two "founders" was the name. They were just another startup with no business sense. He was the one who got them their initial funding before he got tired of their foolishness and took over operations himself.
He was also the main force behind PayPal, and the story of the founder being forced out is more applicable to that situation. They actually did it while he was on an international flight to keep him from interfering.
And saying that he claimed to design the Falcon by himself is pure nonsense. He's always given Tom Mueller credit. And Musk actually was behind a lot of the decisions, including highly technical ones that Mueller didn't like but later admitted were the right ones. Musk is a genius in engineering no matter how you measure it.
If anyone wants to know the real story, just read Ashley Vance's book. He's obviously not a Musk shill and writes about all the ugly stuff as well as the good things.
 
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flyingturtle
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Re: SpaceX - Tests, Launches, Developments

Tue Dec 18, 2018 3:03 pm

Aww, no, they have crapped the launch.


David
Keeping calm is terrorism against those who want to live in fear.
 
parapente
Posts: 2882
Joined: Tue Mar 28, 2006 10:42 pm

Re: SpaceX - Tests, Launches, Developments

Tue Dec 18, 2018 3:08 pm

And the New Shepherd launch earlier.Shows just how sensitive these things still are.Still better to be safe than sorry.Particulary important launch for Spacex.
Still both are due to try again tomorrow so should be fun.
Best of luck to both of them.

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