Author Topic: Could a Falcon 9R fly to 100km altitude and land back?  (Read 21221 times)

Offline aceshigh

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I donīt know how much media and the general population perception is important to a company like SpaceX, which in the end, doesnīt really deal with the general public.

All the while, Blue Origin plans to sell suborbital tourist flights. So marketing is more important to them.

But if marketing is important to SpaceX too, I wonder if the F9R they did those 1000m flights could be used for a 100km flight and then land back. In the short term.

Send a F9R to do the same thing as the Blue Origin rocket in a short term from now, then prepare a press conference to EDUCATE people on the differences between reaching space and reaching orbit, and how much more difficult is to land a rocket coming from a horizontal speed of 30 thousand kilometers per hour on a barge on the middle of the ocean to land a rocket flying straight up and down.


CNN was basically MOCKING SpaceX for BlueOrigin doing it "first" than SpaceX while the F9 crashed. As if they were the same thing.

And Musk tweet will fall on deaf and ignorant ears.


So, would the F9R prototype or the Grasshopper be capable of after short adaptations fly to 100km altitude??

Offline joek

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #1 on: 11/25/2015 12:59 AM »
So, would the F9R prototype or the Grasshopper be capable of after short adaptations fly to 100km altitude??

That was the original plan: to fly, or re-fly an F9R booster to ~100km from Spaceport America.  We still may see it, but SpaceX apparently decided those early tests were better served by their current approach: piggy-backing on existing launches with ASDS recovery.
« Last Edit: 11/25/2015 01:01 AM by joek »

Offline Robotbeat

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #2 on: 11/25/2015 01:00 AM »
Yes, as long as it was mounted like a typical F9 launch and had a nosecap of some sort attached.

Should be a piece of cake, actually. On the way down, they should have enough delta-v left over that they could stay below Mach 1, basically "hovering" all the way down to the ground.
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Offline laika_fr

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #3 on: 11/25/2015 01:11 AM »
Of course it could, but they may be planning a different type of rocket/engine to do so ...

Has previously said SpaceX took a different path over the years and spaceport america was not required anymore.
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Online Johnnyhinbos

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #4 on: 11/25/2015 01:30 AM »
I would think everyone in the "Elon stated that the stage is flying back from the barge to mainland as part of the reuse program" camp would have an opinion on this one.

Personally I feel that SpaceX has the tech maturity to accomplish this, but it would come across as a bit pedantic.

Instead I'd prefer SpaceX focus on its business plan and not be bothered by such distractions, which I'm sure is exactly what it's doing.

Today was a fantastic day in the space industry. We all should pause and marvel at the achievement. My hats off to Blue Origin!

At the same time, do you really suppose SpaceX has put all plans and development on pause during the RTF hold? Do you think that they've not continued to make improvements to their systems from avionics to additive manufacturing during this time? Of course they have. It's an exciting time right now, and I for one can't wait what December will bring...
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Offline aceshigh

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #5 on: 11/25/2015 01:32 AM »
Yes, as long as it was mounted like a typical F9 launch and had a nosecap of some sort attached.

Should be a piece of cake, actually. On the way down, they should have enough delta-v left over that they could stay below Mach 1, basically "hovering" all the way down to the ground.

yes, but my question is more regarding if it would be possible to do it on the short term, just to show the media "if we wanted to do something as simple as that, we would already have done it".

and for the short term, it would be a question of : does the F9R used on those tests (1000m high maximum or there was one that went higher?) is still available? Why didnīt they made any other tests with more altitude? I agree that specifically for SpaceX, there was no use (not their market) , but wasnīt that F9R maybe done JUST for those tests and lacked some components for higher altitudes?

could SpaceX just come in 2 weeks and beat Blue Origin if they wanted? Or would they need much more time for such test?

Offline aceshigh

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #6 on: 11/25/2015 01:34 AM »
I would think everyone in the "Elon stated that the stage is flying back from the barge to mainland as part of the reuse program" camp would have an opinion on this one.

Personally I feel that SpaceX has the tech maturity to accomplish this, but it would come across as a bit pedantic.

Instead I'd prefer SpaceX focus on its business plan and not be bothered by such distractions, which I'm sure is exactly what it's doing.

Today was a fantastic day in the space industry. We all should pause and marvel at the achievement. My hats off to Blue Origin!

At the same time, do you really suppose SpaceX has put all plans and development on pause during the RTF hold? Do you think that they've not continued to make improvements to their systems from avionics to additive manufacturing during this time? Of course they have. It's an exciting time right now, and I for one can't wait what December will bring...

And I quite frakked actually. It was a good achievement by Blue Origins.

But Bezzos media statement made it seem much more than it really was and the media and public swallowed it all! They are comparing DIRECTLY between SpaceX failed Falcon9 landing and Blue Origin landing.

Online eriblo

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #7 on: 11/25/2015 02:32 AM »
Yes, as long as it was mounted like a typical F9 launch and had a nosecap of some sort attached.

Should be a piece of cake, actually. On the way down, they should have enough delta-v left over that they could stay below Mach 1, basically "hovering" all the way down to the ground.

yes, but my question is more regarding if it would be possible to do it on the short term, just to show the media "if we wanted to do something as simple as that, we would already have done it".

and for the short term, it would be a question of : does the F9R used on those tests (1000m high maximum or there was one that went higher?) is still available? Why didnīt they made any other tests with more altitude? I agree that specifically for SpaceX, there was no use (not their market) , but wasnīt that F9R maybe done JUST for those tests and lacked some components for higher altitudes?

could SpaceX just come in 2 weeks and beat Blue Origin if they wanted? Or would they need much more time for such test?
I don't really feel the need for one-upmanship but I believe the answer to your questions are:

Maybe, technically, but no because of red tape. 2 x It blew up. Don't think so. 2 x See answer 1.

F9R-Dev was designed to do this, but had to terminate (save the cows!) on one of the test flights building up to this. (I think that Grasshopper is too heavy to reach 100 km). Both the last F9 1.1 and the RTF F9FT first stage could easily do this and might be ready in two weeks, but it would have to be from Spaceport America and we haven't heard that the ground equipment is ready (and they don't have an active permit AFAIK). Technically it might be possible to truck Jason 3's stage to McGregor, treat it as a F9R-Dev and launch it (although it would likely need to much modification). It would also kill the company and fill a prison block or two.

IMHO, what they are going to do is this: take the RTF F9FT stage and, maybe as soon as three weeks from now, launch it from Florida both higher and and faster while weighted down for sport. Then they are going to land it on a barge as described in some patent (after asking nicely one last time if they might not land it at the launch site instead). And get a big check for it as well.

Offline Elmar Moelzer

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #8 on: 11/25/2015 02:42 AM »
From what I remember, the apogee of the F9 first stage during a normal orbital launch trajectory (with first stage recovery) is 160 km. Mind you that at stage separation, the it is also very far down range and has a very high horizontal velocity (Mach 6, IIRC). So it should easily(!) be able to go up to 100 km and come straight down again. In fact, according to Elon Musk, the first stage alone could do SSTO (but with zero payload).
Either way, the exercise seems rather pointless, since the stage is already coming back from an altitude way above the karman line, even during normal launches (with recovery).
« Last Edit: 11/25/2015 02:46 AM by Elmar Moelzer »

Offline shuttlelegs

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #9 on: 11/25/2015 04:36 AM »
What height did the DC-X ever get to ?



Offline RonM

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Offline spacefairer

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #11 on: 11/25/2015 05:37 AM »
Not yet.  They still need to figure out how to land.  Its tricky I hear.

Offline Paul_G

Yes, as long as it was mounted like a typical F9 launch and had a nosecap of some sort attached.

Should be a piece of cake, actually. On the way down, they should have enough delta-v left over that they could stay below Mach 1, basically "hovering" all the way down to the ground.

Isn't the thrust/weight ratio too high for this - this is why we have the hover slam manoeuvre in the first place - you can't continuously fire the engine as the stage would rise up again.

Out of interest do we know the descent profile of Blue Origin - how many burns does it make on the way down?

Paul

Online Coastal Ron

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #13 on: 11/25/2015 05:47 AM »
Not yet.  They still need to figure out how to land.  Its tricky I hear.

Landing on land back at your launch point is relatively easy.  SpaceX has already demonstrated the ability to do that.  Landing on a small barge at sea after launching from hundreds of miles away and pushing a payload into a precise orbit - that is a lot harder.
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Offline funkyjive

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #14 on: 11/25/2015 06:00 AM »
Yes, as long as it was mounted like a typical F9 launch and had a nosecap of some sort attached.

Should be a piece of cake, actually. On the way down, they should have enough delta-v left over that they could stay below Mach 1, basically "hovering" all the way down to the ground.

Isn't the thrust/weight ratio too high for this - this is why we have the hover slam manoeuvre in the first place - you can't continuously fire the engine as the stage would rise up again.

Out of interest do we know the descent profile of Blue Origin - how many burns does it make on the way down?

Paul
A single landing burn.

Offline spacefairer

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #15 on: 11/25/2015 06:07 AM »
Not yet.  They still need to figure out how to land.  Its tricky I hear.

Landing on land back at your launch point is relatively easy.  SpaceX has already demonstrated the ability to do that.  Landing on a small barge at sea after launching from hundreds of miles away and pushing a payload into a precise orbit - that is a lot harder.

spacex has only ever landed a rocket that has been going relatively slow, a hundred km/h or so.  Quickly going from supersonic to landing is the tricky part.  There have been dozens of short hop rockets that have demonstrated VTOL, its the descent speed that makes 100 km tricky.

-edit- removed an extraneous 'if'
« Last Edit: 11/25/2015 06:25 AM by spacefairer »

Offline guckyfan

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #16 on: 11/25/2015 06:57 AM »
SpaceX could do it with Falcon 9R but they have little interest to do so. They had it planned but then switched to testing with spent stages of orbital flights. Their present plan is to use flown stages for that kind of test. I doubt they will change that plan just to show they can do it similar to Blue Origin.

It has been pointed out that Blue and the Falcon 9R go through not too much different speed ranges. But it is still very, very different. Falcon 9R is a part of an orbital vehicle with razor thin margins and those margins are not getting better through reuse. So they cannot afford hover.

The Blue vehicle in contrast has as much margin as the engineers care to give it and they made generous use of that as the hover and traverse close to the ground shows.

Offline Lumina

Fuel margin is a big deal. Hovering just above the ground fixes all control loop problems that software could not fix in real-time just before. So it's really apples and oranges just on that dimension. The only way to have plenty of fuel margin is to specify a rocket that is too big for its payload task.

There was another factor making it easier for BO to nail the landing. The day and time of the New Shepard flight seems to have been cherry-picked for zero ground-level crosswind at the BO private landing site. See the stationary billowing landing dust cloud in the video here: https://www.youtube.com/watch?v=9pillaOxGCo?t=123.

Low altitude crosswinds further complicate vertical propulsive pinpoint landings, so BO naturally eliminated the crosswind by launching according to a weather forecast. However, for SpaceX a station-keeping barge out in the ocean is virtually guaranteed to have crosswinds and in any case, they can't cherry pick the date of launch.
« Last Edit: 11/25/2015 08:35 AM by Lumina »

Offline tleski

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #18 on: 11/25/2015 11:51 AM »
A pretty decent article in The Verge discussing why Blue Origin's  landing should not be compared with attempts to recover the first stage of F9:

http://www.theverge.com/2015/11/24/9793220/blue-origin-vs-spacex-rocket-landing-jeff-bezos-elon-musk

According to them the F9's first stage reaches the altitude of 124 miles with speeds between 5.5 to 7.5 Mach, which is a lot of energy to dissipate on its way back to the Earth's surface.
I personally don't think SpaceX needs to replicate Blue's experiment just to prove the point.

Offline Jim

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #19 on: 11/25/2015 01:45 PM »
I donīt know how much media and the general population perception is important to a company like SpaceX, which in the end, doesnīt really deal with the general public.

All the while, Blue Origin plans to sell suborbital tourist flights. So marketing is more important to them.

But if marketing is important to SpaceX too, I wonder if the F9R they did those 1000m flights could be used for a 100km flight and then land back. In the short term.

Send a F9R to do the same thing as the Blue Origin rocket in a short term from now, then prepare a press conference to EDUCATE people on the differences between reaching space and reaching orbit, and how much more difficult is to land a rocket coming from a horizontal speed of 30 thousand kilometers per hour on a barge on the middle of the ocean to land a rocket flying straight up and down.


CNN was basically MOCKING SpaceX for BlueOrigin doing it "first" than SpaceX while the F9 crashed. As if they were the same thing.

And Musk tweet will fall on deaf and ignorant ears.


So, would the F9R prototype or the Grasshopper be capable of after short adaptations fly to 100km altitude??

Don't see what the problem is here.   Spacex is also known for stretching the truth.  And the actual speeds do really matter,  it is only a difference in propellant carried.
« Last Edit: 11/25/2015 01:45 PM by Jim »

Offline aceshigh

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #20 on: 11/25/2015 01:47 PM »
A pretty decent article in The Verge discussing why Blue Origin's  landing should not be compared with attempts to recover the first stage of F9:

http://www.theverge.com/2015/11/24/9793220/blue-origin-vs-spacex-rocket-landing-jeff-bezos-elon-musk

According to them the F9's first stage reaches the altitude of 124 miles with speeds between 5.5 to 7.5 Mach, which is a lot of energy to dissipate on its way back to the Earth's surface.
I personally don't think SpaceX needs to replicate Blue's experiment just to prove the point.

according to Wikipedia (and it lists sources), on at least two flights the F9 first stage made itīs turn around at Mach 10 and altitude of 160km.

Offline cdleonard

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #21 on: 11/25/2015 01:52 PM »
SpaceX can definitely do it. They should repurpose the F9R Dev2 for this and fly to no less that 101km. That'll show'em who has the bigger rocket!
« Last Edit: 11/25/2015 01:52 PM by cdleonard »

Offline aceshigh

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #22 on: 11/25/2015 01:53 PM »
A pretty decent article in The Verge discussing why Blue Origin's  landing should not be compared with attempts to recover the first stage of F9:

http://www.theverge.com/2015/11/24/9793220/blue-origin-vs-spacex-rocket-landing-jeff-bezos-elon-musk

According to them the F9's first stage reaches the altitude of 124 miles with speeds between 5.5 to 7.5 Mach, which is a lot of energy to dissipate on its way back to the Earth's surface.
I personally don't think SpaceX needs to replicate Blue's experiment just to prove the point.


this article looked good until...
"The New Shepard isn't meant to go as far up as the Falcon 9, however, which is echoed in the rocket's shape. The vehicle is only designed to take people to sub-orbital space for about four minutes. An object at this height isn't going fast enough to make a full rotation around Earth, so it hasn't quite broken free of the bonds of the planet's gravity and will eventually be pulled back down to the surface."

It looks like if the author thinks orbit is dependent on altitude instead of speed.

also, if you are on orbit, you did not break free of the bonds of the planet's gravity...


SpaceX can definitely do it. They should repurpose the F9R Dev2 for this and fly to no less that 101km. That'll show'em who has the bigger rocket!

I think everyone knows SpaceX has the biggest rocket, the question is that the man with the smaller rocket is saying he can go for a "second round" while SpaceX canīt. Well, of course, he barely broke a sweat in the "first round"!
« Last Edit: 11/25/2015 01:55 PM by aceshigh »

Offline MattMason

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #23 on: 11/25/2015 02:06 PM »
A pretty decent article in The Verge discussing why Blue Origin's  landing should not be compared with attempts to recover the first stage of F9:

http://www.theverge.com/2015/11/24/9793220/blue-origin-vs-spacex-rocket-landing-jeff-bezos-elon-musk

According to them the F9's first stage reaches the altitude of 124 miles with speeds between 5.5 to 7.5 Mach, which is a lot of energy to dissipate on its way back to the Earth's surface.
I personally don't think SpaceX needs to replicate Blue's experiment just to prove the point.


this article looked good until...
"The New Shepard isn't meant to go as far up as the Falcon 9, however, which is echoed in the rocket's shape. The vehicle is only designed to take people to sub-orbital space for about four minutes. An object at this height isn't going fast enough to make a full rotation around Earth, so it hasn't quite broken free of the bonds of the planet's gravity and will eventually be pulled back down to the surface."

It looks like if the author thinks orbit is dependent on altitude instead of speed.

also, if you are on orbit, you did not break free of the bonds of the planet's gravity...


SpaceX can definitely do it. They should repurpose the F9R Dev2 for this and fly to no less that 101km. That'll show'em who has the bigger rocket!

I think everyone knows SpaceX has the biggest rocket, the question is that the man with the smaller rocket is saying he can go for a "second round" while SpaceX canīt. Well, of course, he barely broke a sweat in the "first round"!

Elon Musk's little Twitter storms about the differences of his rocket to Blue Origin's great achievement included a link to an XKCD What-If infographic discussion about the principles of suborbital and orbital flight. The XKCD creator is well-versed in physics, so it bears review for most of us non-space industry folks as a primer to the contrasts of Blue's and SpaceX's attempts.

In short, the New Shepard has little lateral speed--it's not trying to achieve orbit with its payload. A Falcon 9 is moving laterally as well as vertically and needs much more energy to also turn around ("boost back") before then landing after reaching speeds of nearly Mach 10.

(What-If: Orbital Speed)
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Online Coastal Ron

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #24 on: 11/25/2015 02:06 PM »
There have been dozens of short hop rockets that have demonstrated VTOL, its the descent speed that makes 100 km tricky.

Then you haven't been watching what SpaceX has already been able to do with re-entry.

Not taking anything away from Blue Origin, but what SpaceX has been attempting (landing at sea hundreds of miles from the launch site), using a very incremental approach, is far harder than what Blue Origin just accomplished (landing on land back at the launch site).

All of this discussion between and about these two companies is really a tempest in a teapot though, since in two years it will not have mattered who did what first, only who is doing what then.
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Offline randomly

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #25 on: 11/25/2015 02:10 PM »
also, if you are on orbit, you did not break free of the bonds of the planet's gravity...

Well maybe not breaking the bonds of gravity, but neatly sidestepping it...

Offline HMXHMX

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #26 on: 11/25/2015 02:47 PM »
There have been dozens of short hop rockets that have demonstrated VTOL, its the descent speed that makes 100 km tricky.

Then you haven't been watching what SpaceX has already been able to do with re-entry.

Not taking anything away from Blue Origin, but what SpaceX has been attempting (landing at sea hundreds of miles from the launch site), using a very incremental approach, is far harder than what Blue Origin just accomplished (landing on land back at the launch site).

All of this discussion between and about these two companies is really a tempest in a teapot though, since in two years it will not have mattered who did what first, only who is doing what then.

See my comment in the Blue Origin discussion:

http://forum.nasaspaceflight.com/index.php?topic=10685.msg1449488#msg1449488

Offline mvpel

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #27 on: 11/25/2015 02:52 PM »

Quote from: spacefairer link=topic=38879.msg1449350#msg1449350
spacex has only ever landed a rocket that has been going relatively slow, a hundred km/h or so.

They have repeatedly demonstrated landing rockets from hypersonic velocities, starting April 18, 2014. Just because there wasn't a solid surface under CRS3 doesn't mean it didn't make a successful autonomous soft touchdown.
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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #28 on: 11/25/2015 03:02 PM »
Why does it matter what an F9 might or might not be capable of?  The F9 and New Shepard are very different rockets for very different applications but have made individual accomplishments that are similar.  The NS stuck the landing, post mission, first.  The comparison is relative and not all that valuable.

When the F9 sticks the landing, hopefully with the next launch, they will be the first to have accomplished a powered VTOL rocket landing of truly operational hardware after a full mission and not as part of some incremental test.
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Offline tleski

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #29 on: 11/25/2015 03:16 PM »

this article looked good until...
"The New Shepard isn't meant to go as far up as the Falcon 9, however, which is echoed in the rocket's shape. The vehicle is only designed to take people to sub-orbital space for about four minutes. An object at this height isn't going fast enough to make a full rotation around Earth, so it hasn't quite broken free of the bonds of the planet's gravity and will eventually be pulled back down to the surface."

It looks like if the author thinks orbit is dependent on altitude instead of speed.

also, if you are on orbit, you did not break free of the bonds of the planet's gravity...


Well, it is not so rare for people not writing about science/space every day to be confused in this area. That's why I called it "pretty decent" instead of "very good". Apart from this, it is a really nice text and very different from the great majority of other press coverage, which claimed that SpaceX was beaten by Blue in the race to develop a reusable rocket.

Offline spacefairer

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #30 on: 11/25/2015 05:47 PM »
SpaceX could do it with Falcon 9R but they have little interest to do so. They had it planned but then switched to testing with spent stages of orbital flights. Their present plan is to use flown stages for that kind of test. I doubt they will change that plan just to show they can do it similar to Blue Origin.

It has been pointed out that Blue and the Falcon 9R go through not too much different speed ranges. But it is still very, very different. Falcon 9R is a part of an orbital vehicle with razor thin margins and those margins are not getting better through reuse. So they cannot afford hover.

The Blue vehicle in contrast has as much margin as the engineers care to give it and they made generous use of that as the hover and traverse close to the ground shows.

Engineering without margin is gambling.  If Spacex doesn't have any margin then they will never be able to reliably land.  I guarantee they have margin and would do this if they could, but their engine can't throttle enough.

When the F9 sticks the landing, hopefully with the next launch, they will be the first to have accomplished a powered VTOL rocket landing of truly operational hardware after a full mission and not as part of some incremental test.


Spacex landing is the definition of an 'incremental test.'  So was Blue's flight.  A vehicle able to fly the same mission multiple times is a 'truly operational hardware,'  which Blue will have if they can land this thing its next flight.  Spacex landing will not be truly operational hardware until it flies another orbital boost mission.

Offline Elmar Moelzer

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #31 on: 11/25/2015 05:53 PM »
I guarantee they have margin and would do this if they could, but their engine can't throttle enough.
I am wondering how that changes after the latest update to F9. The engine now has a lot more thrust and the vehicle is quite a bite bigger and supposedly also heavier. So assuming that it can still throttle down to the same thrust levels as before (why wouldn't it?), it might not need to slam quite as radically. Not sure if it can hover now, though (even though it almost looked like it hovered last time already).

Offline deltaV

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #32 on: 11/25/2015 06:51 PM »
spacex has only ever landed a rocket that has been going relatively slow, a hundred km/h or so.  Quickly going from supersonic to landing is the tricky part.  There have been dozens of short hop rockets that have demonstrated VTOL, its the descent speed that makes 100 km tricky.

SpaceX's experiments piggybacking on customer F9 flights have demonstrated that they can do the "tricky part" of going from supersonic to just before landing. They've demonstrated the landing part during the grasshopper program and their landing on the sea. They have all the pieces they just haven't done everything right in one flight yet.

Offline spacefairer

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #33 on: 11/25/2015 06:59 PM »
spacex has only ever landed a rocket that has been going relatively slow, a hundred km/h or so.  Quickly going from supersonic to landing is the tricky part.  There have been dozens of short hop rockets that have demonstrated VTOL, its the descent speed that makes 100 km tricky.

SpaceX's experiments piggybacking on customer F9 flights have demonstrated that they can do the "tricky part" of going from supersonic to just before landing. They've demonstrated the landing part during the grasshopper program and their landing on the sea. They have all the pieces they just haven't done everything right in one flight yet.

Grasshopper was ballasted so T=W could be done with M1D.  So no.

Offline guckyfan

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #34 on: 11/25/2015 07:04 PM »
I guarantee they have margin and would do this if they could, but their engine can't throttle enough.
I am wondering how that changes after the latest update to F9. The engine now has a lot more thrust and the vehicle is quite a bite bigger and supposedly also heavier. So assuming that it can still throttle down to the same thrust levels as before (why wouldn't it?), it might not need to slam quite as radically. Not sure if it can hover now, though (even though it almost looked like it hovered last time already).

The first stage is mostly the same, just a little longer interstage. Question is does the full thrust Merlin have the same lowest thrust setting as before? Probably yes so no notable difference.

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #35 on: 11/25/2015 07:20 PM »
When the F9 sticks the landing, hopefully with the next launch, they will be the first to have accomplished a powered VTOL rocket landing of truly operational hardware after a full mission and not as part of some incremental test.

Spacex landing is the definition of an 'incremental test.'  So was Blue's flight.  A vehicle able to fly the same mission multiple times is a 'truly operational hardware,'  which Blue will have if they can land this thing its next flight.  Spacex landing will not be truly operational hardware until it flies another orbital boost mission.
Nice job missing the point and parsing out context!  SX hardware is doing this while performing commercial operations on orbital missions and BO hardware is performing sub-orbital tests.  I'm trying to illustrate that SX and BO operations are not comparable despite the similar goals of launch-land-relaunch.
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Offline spacefairer

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #36 on: 11/25/2015 07:37 PM »
When the F9 sticks the landing, hopefully with the next launch, they will be the first to have accomplished a powered VTOL rocket landing of truly operational hardware after a full mission and not as part of some incremental test.

Spacex landing is the definition of an 'incremental test.'  So was Blue's flight.  A vehicle able to fly the same mission multiple times is a 'truly operational hardware,'  which Blue will have if they can land this thing its next flight.  Spacex landing will not be truly operational hardware until it flies another orbital boost mission.
Nice job missing the point and parsing out context!  SX hardware is doing this while performing commercial operations on orbital missions and BO hardware is performing sub-orbital tests.  I'm trying to illustrate that SX and BO operations are not comparable despite the similar goals of launch-land-relaunch.

Sorry, I was assuming that this the detail that you were using to say that spacex will be "the first to have accomplished a powered VTOL rocket landing of truly operational hardware after a full mission and not as part of some incremental test."  since Blue just "accomplished a powered VTOL rocket landing of truly operational hardware after a full mission." 

So please explain to me how the following statement is true:
When the F9 sticks the landing, hopefully with the next launch, they will be the first to have accomplished a powered VTOL rocket landing of truly operational hardware after a full mission and not as part of some incremental test.

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #37 on: 11/25/2015 07:41 PM »
When the F9 sticks the landing, hopefully with the next launch, they will be the first to have accomplished a powered VTOL rocket landing of truly operational hardware after a full mission and not as part of some incremental test.

Spacex landing is the definition of an 'incremental test.'  So was Blue's flight.  A vehicle able to fly the same mission multiple times is a 'truly operational hardware,'  which Blue will have if they can land this thing its next flight.  Spacex landing will not be truly operational hardware until it flies another orbital boost mission.
Nice job missing the point and parsing out context!  SX hardware is doing this while performing commercial operations on orbital missions and BO hardware is performing sub-orbital tests.  I'm trying to illustrate that SX and BO operations are not comparable despite the similar goals of launch-land-relaunch.

So are you saying that Chuck Yeager wasn't the first pilot to break the sound barrier since he was a test pilot in an experimental plane? It was in fact the pilot who did it first with operational hardware? I don't know who that was... Do you?

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #38 on: 11/25/2015 07:53 PM »

Sorry, I was assuming that this the detail that you were using to say that spacex will be "the first to have accomplished a powered VTOL rocket landing of truly operational hardware after a full mission and not as part of some incremental test."  since Blue just "accomplished a powered VTOL rocket landing of truly operational hardware after a full mission." 

So please explain to me how the following statement is true:
When the F9 sticks the landing, hopefully with the next launch, they will be the first to have accomplished a powered VTOL rocket landing of truly operational hardware after a full mission and not as part of some incremental test.
By "operational" I am indicating commercial operation.  SX operational versus BO test.  SX production hardware versus BO prototype hardware.
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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #39 on: 11/25/2015 08:03 PM »
Nice job missing the point and parsing out context!  SX hardware is doing this while performing commercial operations on orbital missions and BO hardware is performing sub-orbital tests.  I'm trying to illustrate that SX and BO operations are not comparable despite the similar goals of launch-land-relaunch.
So are you saying that Chuck Yeager wasn't the first pilot to break the sound barrier since he was a test pilot in an experimental plane? It was in fact the pilot who did it first with operational hardware? I don't know who that was... Do you?
The Chuck Yeager moment of sticking a rocket landing is long past.
gyatm . . . Fern

Offline spacefairer

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #40 on: 11/25/2015 08:16 PM »
Please remind me the last time a rocket landed vertically after a hypersonic flight.  If spacex's "landings on the ocean" were controlled and precise enough to be recoverable had it been on land then they would have landed a stage on the barge by now.  It sounded impressive back then when they claimed it would be easy to transition from that to landing on a barge, but that clearly was not the case.

Spacex's landing attempts are tests.  Just ask Elon.

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #41 on: 11/25/2015 08:26 PM »
Nice job missing the point and parsing out context!  SX hardware is doing this while performing commercial operations on orbital missions and BO hardware is performing sub-orbital tests.  I'm trying to illustrate that SX and BO operations are not comparable despite the similar goals of launch-land-relaunch.
So are you saying that Chuck Yeager wasn't the first pilot to break the sound barrier since he was a test pilot in an experimental plane? It was in fact the pilot who did it first with operational hardware? I don't know who that was... Do you?
The Chuck Yeager moment of sticking a rocket landing is long past.

So is the moment of thinking SpaceX would stick a rocket landing first ;-)

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #42 on: 11/25/2015 09:49 PM »
Yes, as long as it was mounted like a typical F9 launch and had a nosecap of some sort attached.

Should be a piece of cake, actually. On the way down, they should have enough delta-v left over that they could stay below Mach 1, basically "hovering" all the way down to the ground.

yes, but my question is more regarding if it would be possible to do it on the short term, just to show the media "if we wanted to do something as simple as that, we would already have done it".

and for the short term, it would be a question of : does the F9R used on those tests (1000m high maximum or there was one that went higher?) is still available? Why didnīt they made any other tests with more altitude? I agree that specifically for SpaceX, there was no use (not their market) , but wasnīt that F9R maybe done JUST for those tests and lacked some components for higher altitudes?

could SpaceX just come in 2 weeks and beat Blue Origin if they wanted? Or would they need much more time for such test?
Only if the launch pad at Spaceport America were ready (and it's not).  They can't do vertical "hops" at KSC or Vandenberg.  They don't have a proper lunch pad at McGregor because they would never get FAA clearance there (among other limitations).  But most importantly, there is no point.

Elon lost some bragging rights today.  He'll live.  Gwynne will tell Elon to suck it up.  Gravity willing, SpaceX will RTF.  Blue will go back to super secret "we only show our successes mode" for another completely indeterminate amount of time.  If Blue play their cards right, they might fly (suborbital) with people on board before SpaceX ferries astronauts to the ISS.  If so, Bezos will poke at Elon.  If not, Elon will poke at Bezos.

It takes a big ego to start a rocket company.  It takes a resilient ego to stay in the business.  Musk and Bezos have big resilient egos and rocketry is all the better for it.
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Offline Darkseraph

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #43 on: 11/25/2015 10:06 PM »
Could you omit the second stage, fly the first stage (or an F9 derived stage) on a very high suborbital trajectory, land it on the barge and then land a dragon derived capsule either in the water for recovery or a powered landing on a barge?


That probably would be much more expensive than what everyone else is doing because of the expensive hardware and a barge doesn't allow for quick turn around times. But I am just throwing it out there as a suggestion for how they could attempt some suborbital tourism thingy. This thread is presumably a response to what Blue Origin has just achieved.

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Offline tleski

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #44 on: 11/25/2015 11:28 PM »
Could you omit the second stage, fly the first stage (or an F9 derived stage) on a very high suborbital trajectory, land it on the barge and then land a dragon derived capsule either in the water for recovery or a powered landing on a barge?
(...)

This has already been extensively discussed here:

http://forum.nasaspaceflight.com/index.php?topic=36738.0

Offline Robotbeat

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #45 on: 11/25/2015 11:36 PM »
Not yet.  They still need to figure out how to land.  Its tricky I hear.
They landed Grasshopper and F9Rdev1 multiple times and came very near for many F9 booster recoveries (failed due to loss of hydraulics and a defect in one of the valves or due to not having a droneship to land on). 100km is so easy in comparison they could add a bunch of ballast propellant like F9dev1 did and do basically the same thing F9dev1 demonstrated many, many times.
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Offline Robotbeat

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #46 on: 11/25/2015 11:37 PM »
Nice job missing the point and parsing out context!  SX hardware is doing this while performing commercial operations on orbital missions and BO hardware is performing sub-orbital tests.  I'm trying to illustrate that SX and BO operations are not comparable despite the similar goals of launch-land-relaunch.
So are you saying that Chuck Yeager wasn't the first pilot to break the sound barrier since he was a test pilot in an experimental plane? It was in fact the pilot who did it first with operational hardware? I don't know who that was... Do you?
The Chuck Yeager moment of sticking a rocket landing is long past.

So is the moment of thinking SpaceX would stick a rocket landing first ;-)
DC-X stuck it first.
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

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Offline mvpel

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #47 on: 11/25/2015 11:48 PM »
Please remind me the last time a rocket landed vertically after a hypersonic flight.  If spacex's "landings on the ocean" were controlled and precise enough to be recoverable had it been on land then they would have landed a stage on the barge by now.

That doesn't follow. The two ASDS landing failures arose from very specific circumstances: 1. running out of hydraulic fluid for the new grid fins, and 2. throttle valve stiction. The CRS-3 video doesn't show any indications of being anything other than controlled and precise enough to be recoverable on land in the same manner as the F9R-Dev1 flights.
"Ugly programs are like ugly suspension bridges: they're much more liable to collapse than pretty ones, because the way humans (especially engineer-humans) perceive beauty is intimately related to our ability to process and understand complexity. A language that makes it hard to write elegant code makes it hard to write good code." - Eric S. Raymond

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #48 on: 11/25/2015 11:49 PM »
Nice job missing the point and parsing out context!  SX hardware is doing this while performing commercial operations on orbital missions and BO hardware is performing sub-orbital tests.  I'm trying to illustrate that SX and BO operations are not comparable despite the similar goals of launch-land-relaunch.
So are you saying that Chuck Yeager wasn't the first pilot to break the sound barrier since he was a test pilot in an experimental plane? It was in fact the pilot who did it first with operational hardware? I don't know who that was... Do you?
The Chuck Yeager moment of sticking a rocket landing is long past.

So is the moment of thinking SpaceX would stick a rocket landing first ;-)
DC-X stuck it first.

Heck yea it did! Does the Apollo Lunar Module get any recognition for a vertical landing vertical takeoff? Or does it have to be in the proper order ;)

Offline PreferToLurk

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #49 on: 11/26/2015 12:39 AM »
Grasshopper was ballasted so T=W could be done with M1D.  So no.

Grasshopper was ballasted but there is at least one verified landing at T > W.


http://forum.nasaspaceflight.com/index.php?topic=32718.msg1116648#msg1116648


The video analysis done in the linked thread show a Grasshopper landing with T/W at 1.8

Offline meekGee

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #50 on: 11/27/2015 05:11 AM »
Yes, as long as it was mounted like a typical F9 launch and had a nosecap of some sort attached.

Should be a piece of cake, actually. On the way down, they should have enough delta-v left over that they could stay below Mach 1, basically "hovering" all the way down to the ground.

yes, but my question is more regarding if it would be possible to do it on the short term, just to show the media "if we wanted to do something as simple as that, we would already have done it".

and for the short term, it would be a question of : does the F9R used on those tests (1000m high maximum or there was one that went higher?) is still available? Why didnīt they made any other tests with more altitude? I agree that specifically for SpaceX, there was no use (not their market) , but wasnīt that F9R maybe done JUST for those tests and lacked some components for higher altitudes?

could SpaceX just come in 2 weeks and beat Blue Origin if they wanted? Or would they need much more time for such test?
I don't really feel the need for one-upmanship but I believe the answer to your questions are:

Maybe, technically, but no because of red tape. 2 x It blew up. Don't think so. 2 x See answer 1.

F9R-Dev was designed to do this, but had to terminate (save the cows!) on one of the test flights building up to this. (I think that Grasshopper is too heavy to reach 100 km). Both the last F9 1.1 and the RTF F9FT first stage could easily do this and might be ready in two weeks, but it would have to be from Spaceport America and we haven't heard that the ground equipment is ready (and they don't have an active permit AFAIK). Technically it might be possible to truck Jason 3's stage to McGregor, treat it as a F9R-Dev and launch it (although it would likely need to much modification). It would also kill the company and fill a prison block or two.

IMHO, what they are going to do is this: take the RTF F9FT stage and, maybe as soon as three weeks from now, launch it from Florida both higher and and faster while weighted down for sport. Then they are going to land it on a barge as described in some patent (after asking nicely one last time if they might not land it at the launch site instead). And get a big check for it as well.

Bezos was obviously trolling Musk (one good turn deserves another), with some (BO inspired) headlines proclaiming that BO's rocket "went to outer space and back".

Eye roll.

And then Elon fed the troll, and now all the other trolls see that there's food, so they come out to eat...

---

The BO flight one-upped the GH flights, but in the grand scheme of things if you compare to the combined achievement of GH and F9R, the BO flight is a distant second place.

Too subtle of an argument for the general media, but who cares.

What matters is how far each company has to go until they recover first stages, and the answer is that SpaceX is on the verge of doing so, and BO doesn't even have a real vehicle to recover.

So good for BO, but they'll join the club when they reach orbit - just like SpaceX did.  They are on the right track though (unlike the other suborbital ventures) and will get there soon enough.
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Offline CuddlyRocket

DC-X stuck it first.

Heck yea it did! Does the Apollo Lunar Module get any recognition for a vertical landing vertical takeoff? Or does it have to be in the proper order ;)

'The first reusable rocket'. What a tangle of definitions!

Are we just talking about rockets that get into space? Because if not, I wouldn't be surprised of one of Goddard's rockets or those of other pioneers weren't reused. What definition of space are we using? Bezos, Musk and the media seem to be using the notional Karman line definition, which seems to becoming generally accepted for these record-breaking debates. Joseph Walker did that twice in an X-15 in 1963.

Of course, a rocket is only reusable in principle (if at all) until it's actually reused to get into space a second time. Assertions of capability are just words; demonstrated capability is what's required. I'm not sure if Walker used the same X-15, but Spaceship One was reused - for that matter, so were the various Space Shuttle Orbiters.

Are we insisting the rocket launch under its own power? Then Bezos probably does have the bragging rights once he's actually got the same rocket into space a second time.

Musk does have some points to make about the difference between sub-orbital and orbital rockets. But even if the F-9 first stage could make it into orbit by itself it cannot then land and be reused. Of course, once he sticks a landing and gets the same stage into space again he can then claim the rights to the first orbital-capable, reusable rocket - well, once he's demonstrated such a stage can actually get into orbit!

Regardless though, Musk would have been well advised not to make any of his points himself and to just stuck to his congratulations. There would be plenty of people making similar arguments and he could respond to questions on that line at a later date.
« Last Edit: 11/27/2015 05:34 AM by CuddlyRocket »

Offline leaflion

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #52 on: 11/27/2015 05:40 AM »
...BO doesn't even have a real vehicle to recover.

Sorry, what did they recover on Monday then?

Clearly you've drunk the "It doesn't matter if it isn't going to orbit" Kool-aid.  When did the "orbital club" become so pretentious that anything that doesn't fly orbitally (which F9R doesn't do) isn't a vehicle.

Excuse them for accomplishing something.

Offline guckyfan

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #53 on: 11/27/2015 06:17 AM »
Musk does have some points to make about the difference between sub-orbital and orbital rockets. But even if the F-9 first stage could make it into orbit by itself it cannot then land and be reused. Of course, once he sticks a landing and gets the same stage into space again he can then claim the rights to the first orbital-capable, reusable rocket - well, once he's demonstrated such a stage can actually get into orbit!

That first stage does not need to make orbit for that claim. It is part of a commercial orbital vehicle. That means it has to work on a razor thin margin to deliver meaningful payload to orbit even considered the first stage never makes orbit. The Blue Origin vehicle has no such constraint. It can have all the margin the designers care to give it and they gave plenty of margin as the translate and hover demonstrate. This is what makes the design of the Falcon 9 first stage so much more demanding.

To be sure, the Blue Origin success in launch and landing is still a major achievement. I have not seen anyone denying that.

Regardless though, Musk would have been well advised not to make any of his points himself and to just stuck to his congratulations. There would be plenty of people making similar arguments and he could respond to questions on that line at a later date.

True, Elon Musk was clearly frakked off and did not hide it. He probably should have.
« Last Edit: 11/27/2015 06:18 AM by guckyfan »

Online AncientU

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #54 on: 11/27/2015 11:41 AM »
Competition is great.
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Offline rpapo

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #55 on: 11/27/2015 11:59 AM »
In competition such as this, the real winner is the customer.  The competitors get stronger and more efficient, and the customer gets a better product for a lower price.

Providing the competitors survive.  So please, let's root for both sides in this battle.
An Apollo fanboy . . . fifty years ago.

Offline laszlo

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #56 on: 11/27/2015 12:08 PM »
The only way to have plenty of fuel margin is to specify a rocket that is too big for its payload task.

That's funny. Remember back when the only way to make rockets recoverable was if the rocket was too big for its payload task?

The rocket equation hasn't changed, must be the fan base.

Offline laszlo

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #57 on: 11/27/2015 12:10 PM »
Heck yea it did! Does the Apollo Lunar Module get any recognition for a vertical landing vertical takeoff? Or does it have to be in the proper order ;)

Not to mention SSTO and a rendezvous and being man-rated.

Offline meekGee

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #58 on: 11/27/2015 03:05 PM »
...BO doesn't even have a real vehicle to recover.

Sorry, what did they recover on Monday then?

Clearly you've drunk the "It doesn't matter if it isn't going to orbit" Kool-aid.  When did the "orbital club" become so pretentious that anything that doesn't fly orbitally (which F9R doesn't do) isn't a vehicle.

Excuse them for accomplishing something.
Ever since the goal was to get to orbit.  Suborbital flight is something completely different.

F9R first stage is indeed suborbital, but is part of an orbital system.

BO's system is not.  It is using technology that is on the right track of becoming one, but is still far from doing so.
ABCD - Always Be Counting Down

Offline QuantumG

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #59 on: 11/28/2015 01:38 AM »
Personally, I'll judge the winner on the price of their stock.. and seeing as I can't buy either of them, they're both losers.  ;D
Jeff Bezos has billions to spend on rockets and can go at whatever pace he likes! Wow! What pace is he going at? Well... have you heard of Zeno's paradox?

Offline Zed_Noir

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #60 on: 11/28/2015 04:13 AM »
Personally, I'll judge the winner on the price of their stock.. and seeing as I can't buy either of them, they're both losers.  ;D

You could contribute a $1B or so like Alphabet Inc. :P

Offline MP99



Personally, I'll judge the winner on the price of their stock.. and seeing as I can't buy either of them, they're both losers.  ;D

Perhaps they'll both be winners when we get to the stage that the stock price goes up on the back of "colonize Mars" talk, and down on "we're reining in our plans".

Cheers, Martin

Offline OxCartMark

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #62 on: 12/03/2015 04:06 PM »
Regardless though, Musk would have been well advised not to make any of his points himself and to just stuck to his congratulations. There would be plenty of people making similar arguments and he could respond to questions on that line at a later date.

Offline Ludus

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #63 on: 12/06/2015 03:27 AM »
I don't think there's much doubt that if SpaceX wanted to compete with Blue Origin and Virgin Galactic in the suborbital space tourism market, they could have had a version of grasshopper and "Tourist Dragon" taking people on hops above the Karman line for a few minutes for $250K a ticket.

If they did that once a week all year they'd get about as much revenue as 1 orbital launch and contribute very little if anything to developing tech they're interested in.

Offline QuantumG

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #64 on: 12/06/2015 04:43 AM »
How about developing support for the multi-billion dollar space program they want the public to pay for? The entire culture could be changed by suborbital tourism... if anyone would actually start flying, already.
Jeff Bezos has billions to spend on rockets and can go at whatever pace he likes! Wow! What pace is he going at? Well... have you heard of Zeno's paradox?

Offline woods170

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #65 on: 12/07/2015 06:38 AM »
How about developing support for the multi-billion dollar space program they want the public to pay for? The entire culture could be changed by suborbital tourism... if anyone would actually start flying, already.

Bezos is probably closest to doing that and sub-orbital flights on that vehicle will be for the very-rich only. If and when VG finally starts flying they will face a similar situation. You may have noticed that the number of paying customers for VG is not exactly running into the many thousands.

Offline NovaSilisko

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #66 on: 12/07/2015 08:32 AM »
How about developing support for the multi-billion dollar space program they want the public to pay for? The entire culture could be changed by suborbital tourism... if anyone would actually start flying, already.

Bezos is probably closest to doing that and sub-orbital flights on that vehicle will be for the very-rich only. If and when VG finally starts flying they will face a similar situation. You may have noticed that the number of paying customers for VG is not exactly running into the many thousands.

I can see Blue Origin's ads already.

"Virgin Galactic customers! Still grounded? Come take a ride on the New Shepard, with an exclusive 25% discount! Limited time offer!"

 ::)
« Last Edit: 12/07/2015 08:33 AM by NovaSilisko »

Offline woods170

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #67 on: 12/07/2015 11:19 AM »
How about developing support for the multi-billion dollar space program they want the public to pay for? The entire culture could be changed by suborbital tourism... if anyone would actually start flying, already.

Bezos is probably closest to doing that and sub-orbital flights on that vehicle will be for the very-rich only. If and when VG finally starts flying they will face a similar situation. You may have noticed that the number of paying customers for VG is not exactly running into the many thousands.

I can see Blue Origin's ads already.

"Virgin Galactic customers! Still grounded? Come take a ride on the New Shepard, with an exclusive 25% discount! Limited time offer!"

 ::)
Nope. Not gonna happen. That's not Jeff's style.

Offline majormajor42

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #68 on: 12/07/2015 12:43 PM »
Could you omit the second stage, fly the first stage (or an F9 derived stage) on a very high suborbital trajectory, land it on the barge and then land a dragon derived capsule either in the water for recovery or a powered landing on a barge?
(...)

This has already been extensively discussed here:

http://forum.nasaspaceflight.com/index.php?topic=36738.0

Thanks for posting that thread. I remembered the "joyride" discussion as well. I think the general consensus was "sure, but why would they?"

SpaceX is hunting down $100/lb launch costs. That is the main reason that landing the first stage will be so celebrated, as a giant leap in the direction of frequent less expensive access to space and the disruptive possibilities that it allows.
...water is life and it is out there, where we intend to go. I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man or machine on a body such as the Moon and harvest a cup of water for a human to drink or process into fuel for their craft.

Online dror

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #69 on: 12/16/2015 05:51 PM »
This has already been extensively discussed here:
http://forum.nasaspaceflight.com/index.php?topic=36738.0
Thanks for posting that thread. I remembered the "joyride" discussion as well. I think the general consensus was "sure, but why would they?"

"Could a Falcon 9R fly to 100km altitude and land back?"
"sure, but why would they?"

So,

"Could a Falcon 9 seconed stage fly a Dragon 2 from ground up to 100km altitude and land back together?"

If it's not fully fuled,
with sea-level merlin
and some legs...
Flying attached and landing together with the dragons superdracos.

Can somebody here calculate to which hight could this system get?
« Last Edit: 12/16/2015 05:52 PM by dror »
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Offline Zed_Noir

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #70 on: 12/16/2015 06:35 PM »
Quote

So,

"Could a Falcon 9 seconed stage fly a Dragon 2 from ground up to 100km altitude and land back together?"

If it's not fully fuled,
with sea-level merlin
and some legs...
Flying attached and landing together with the dragons superdracos.

Can somebody here calculate to which hight could this system get?

Not workable. The excessive thrust from the Merlin will make landings in your configuration almost impossible. One Merlin is already too powerful for the Falcon 9 core which is heavier than your configuration.

Online dror

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #71 on: 12/16/2015 07:01 PM »
Quote

So,

"Could a Falcon 9 seconed stage fly a Dragon 2 from ground up to 100km altitude and land back together?"

If it's not fully fuled,
with sea-level merlin
and some legs...
Flying attached and landing together with the dragons superdracos.

Can somebody here calculate to which hight could this system get?

Not workable. The excessive thrust from the Merlin will make landings in your configuration almost impossible. One Merlin is already too powerful for the Falcon 9 core which is heavier than your configuration.
I meant that the combo will not seperate.
The two components will fly and land attached to each other using the merlin for liftoff and the capsule's built in superdracos for landing.
So the Merlin being too powerfull for landing is irrelevant for that question.
That aside, I am more interested in the theoretical altitude to which a singel full thrust merlin can lift a dragon 2 than in the feasibility of that to actually work.
« Last Edit: 12/16/2015 07:44 PM by dror »
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Offline S.Paulissen

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #72 on: 12/17/2015 03:19 PM »
My back of the envelope calculations suggest that a Falcon9 second stage with a 6000kg Dragon 2 payload and 5900 dry weight (the estimated 4900kg  mass of the v1.1 second stage plus 1000kg 'landing kit' and 90000kg propellant) going straight up would achieve in the ballpark of 700km assuming that the super dracos had enough performance in the 6000kg to land the stack on their own from terminal velocity and that air resistance doesn't effect acceleration much when launching straight up.  I also conservatively assumed 290s average ISP from the single merlin engine for the duration of its burn.

Details:   
The average acceleration was ~5.9m/s^2 for a 389s duration burn that imparts 6109m/s dV. 

When 389s of gravity losses are accounted for, the stage would be accelerated to ~2300m/s (Mach 7.8) after having traveled to 446.7km altitude. 

The stage would then coast for 223.6s to reach apogee after travelling another 268.7km for a total altitude of ~715km. 

If I figure in 1000m/s of aerodynamic velocity losses velocity at MECO is only 1300m/s (Mach 4.3) and at 252km altitude.  The coast would only last 132s before apogee reaching 'only' 338km altitude.
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Offline deltaV

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #73 on: 12/20/2015 07:42 PM »
The stage would then coast for 223.6s to reach apogee after travelling another 268.7km for a total altitude of ~715km.

Have you estimated the acceleration the capsule would encounter on re-entry from that altitude? I fear it would exceed what people would volunteer for.

Offline S.Paulissen

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #74 on: 12/21/2015 12:00 AM »
The stage would then coast for 223.6s to reach apogee after travelling another 268.7km for a total altitude of ~715km.

Have you estimated the acceleration the capsule would encounter on re-entry from that altitude? I fear it would exceed what people would volunteer for.

Understatement of the decade, right there!    It's around 27.4g.  EDIT: which is actually a pretty good estimation based on the old ICBM-monkey launches that pulled ~26g with straight up and down launches (the monkey lived!)

EDIT:  I have to thank you, for making me go back and review my reentry estimations.  I also calculated that New Shepard, reentry at somewhere around 5g if they reentered without a braking burn from 100km, this is an overestimation because the equation I use ignores gravity as the dominant force is drag, which is not exclusively true with these straight up and down hops to the edge of the atmosphere rather than reentering from orbital velocity. 
« Last Edit: 12/21/2015 04:32 AM by Exclavion »
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Offline CJ

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #75 on: 12/22/2015 02:12 AM »

I suspect that tonight, we've seen SpaceX provide a definitive answer to this thread's title question: "Could a Falcon 9R fly to 100km altitude and land back?".

They answered it by doing it.

I don't know the altitude at staging, but if memory serves it's often around 80km. The boostback burn puts the F9 on a lob trajectory back to the pad, so I really don't see how that could happen without the stage exceeding 100km altitude after the boostback burn.

Offline QuantumG

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #76 on: 12/22/2015 02:25 AM »
The apogee of the first stage was 200 km.
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Online AncientU

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #77 on: 12/22/2015 02:27 AM »
Time to move along folks...  nothing to see here.
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Offline JAFO

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #78 on: 12/22/2015 02:29 AM »
I think the question now is: Could New Shepard fly to 200km altitude (and downrange ?? km) and land back?
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Offline QuantumG

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #79 on: 12/22/2015 02:40 AM »
Could a Falcon 9R fly to 100km altitude and land back after completing a full orbit? Maybe it could Virginia, maybe it could.
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Offline Ben the Space Brit

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #80 on: 12/22/2015 11:10 AM »
I still like the idea of putting a modified Crewed Dragon on top of an F9R and using it for suborbital tourist rides.
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Offline CraigLieb

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #81 on: 12/22/2015 06:38 PM »
Tangential question (requesting general speculation based on the last launch parameters): 
If after the 1st stage was done with its primary task, what if it used all its remaining fuel to boost to orbital velocity rather than return stage burns, landing burns, etc. Would it have been able to orbit at least once before reentry?
Given: somewhat empty stage 1, at altitude greater than 100 km, already at 5000 km/sec. what kind of delta v boost would it need to do a 100 km orbit?  Was the launch profile too lofted for that kind of thing?  Air resistance still too high at that altitude?

Any takers of the challenge?
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Offline hkultala

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #82 on: 12/22/2015 06:46 PM »
Tangential question (requesting general speculation based on the last launch parameters): 
If after the 1st stage was done with its primary task, what if it used all its remaining fuel to boost to orbital velocity rather than return stage burns, landing burns, etc. Would it have been able to orbit at least once before reentry?
Given: somewhat empty stage 1, at altitude greater than 100 km, already at 5000 km/sec.

5000km/sec speed is not close to orbital speed. It's much higher speed than escape speed from the solar system.

And Falcon 9 first stage cannot reach it.


The speed at staging was about 5900 km/h which means ~1640 m/s.

This is about 6km/s short of orbital velocity, so at least 6km/s delta-v is needed to get from that to orbit.
And 6km/s is way too much.  And there would be no point of having second stage on LEO launches if first stage would anyway reach orbital velocity.
« Last Edit: 12/22/2015 06:53 PM by hkultala »

Online Lars-J

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #83 on: 12/22/2015 06:48 PM »
Tangential question (requesting general speculation based on the last launch parameters): 
If after the 1st stage was done with its primary task, what if it used all its remaining fuel to boost to orbital velocity rather than return stage burns, landing burns, etc. Would it have been able to orbit at least once before reentry?

It would not be enough. Musk has mentioned that the stage 1 one could probably reach orbit on its own - with no upper stage or payload - although it would not be able to come back.

Given this information, it is pretty clear that after dropping off the 2nd stage and payload, it would have fallen far short of reaching orbit if it tried. Remember that the first stage in this mission only provided ~1/4th of the delta V needed for orbit.
« Last Edit: 12/22/2015 06:50 PM by Lars-J »

Offline Bob Shaw

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #84 on: 12/22/2015 07:14 PM »

Heck yea it did! Does the Apollo Lunar Module get any recognition for a vertical landing vertical takeoff? Or does it have to be in the proper order ;)

In that case, I bid Surveyor 5.

Offline JasonAW3

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #85 on: 12/22/2015 07:40 PM »
Amusing thought here;

     If the BFR winds up being capible of getting itself and a small payload into orbit with a single stage, I wonder how hard it would be to go, "Dry for Wet" with the stage and convert it into a "Super Skylab?

     Doing it with a Falcon 9 maybe possible, but I'm not sure the volume constraings would make the effort worth the cost.
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Offline QuantumG

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #86 on: 12/22/2015 10:53 PM »
It would not be enough. Musk has mentioned that the stage 1 one could probably reach orbit on its own - with no upper stage or payload - although it would not be able to come back.

By my math it'd do about 9500 m/s and still have whatever is usually required for a drone ship return. If your goal is to do a "single orbit" flight, that's excessive. You could do a bigger "boost back" burn to slow down for entry interface. If you put a heat shield inside a faring on top of the first stage, drop off the faring on ascent and use the heat shield to slow down for reentry, that should do it. Not that there'd be much point.

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Offline inventodoc

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #87 on: 12/22/2015 11:05 PM »
Amusing thought here;

     If the BFR winds up being capible of getting itself and a small payload into orbit with a single stage, I wonder how hard it would be to go, "Dry for Wet" with the stage and convert it into a "Super Skylab?

     Doing it with a Falcon 9 maybe possible, but I'm not sure the volume constraings would make the effort worth the cost.

Either a nice big dry space or Wet to Dry is the way to go!  I'd love to see Skylab and original Von Braun vision space stations. 

Offline Dante80

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #88 on: 12/27/2015 06:44 AM »
It would not be enough. Musk has mentioned that the stage 1 one could probably reach orbit on its own - with no upper stage or payload - although it would not be able to come back.

By my math it'd do about 9500 m/s and still have whatever is usually required for a drone ship return. If your goal is to do a "single orbit" flight, that's excessive. You could do a bigger "boost back" burn to slow down for entry interface. If you put a heat shield inside a faring on top of the first stage, drop off the faring on ascent and use the heat shield to slow down for reentry, that should do it. Not that there'd be much point.

The discussion is purely theoretical of course, but it would not be easy for that to work. Most on the mass is on the engine side, and the stage is 48m long. This means that trying to balance re-entry on the other side (interstage heat shield) would be very, very hard.
« Last Edit: 12/27/2015 06:45 AM by Dante80 »

Offline QuantumG

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #89 on: 12/28/2015 12:08 AM »
The discussion is purely theoretical of course, but it would not be easy for that to work. Most on the mass is on the engine side, and the stage is 48m long. This means that trying to balance re-entry on the other side (interstage heat shield) would be very, very hard.

Yep, it's called a "death swoop" and it generally requires a powered reentry.
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Offline Rik ISS-fan

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #90 on: 01/02/2016 04:09 PM »
The original question has been ansered. Could Falcon 9R fly to 100km altitude and land back. YES, Falcon 9R staged at 80km, with a speed of 5,? Km/h (roughly mach5). It restarted 3engines to return to the landing pad and reached a apogee of over 200km before it landed after two one engine burns. (Right?)
Lets change the question in: How does Falcon 9R compare to the Darpa XS-1 requirements?
With changes are required to reach the xs-1 requirements?

The requirements for Darpa XS-1 are:
- It should reach mach10,
- cost less than 5mln to launch.
- can launch 10 times in 10 days.
- with an expendable upper-stage a payload with a mass between 3000-5000 pounds can be launched

My impression is that F9R can launch more than 25 000 pounds for about 10mln. And can relaunch within 48 hours (so 5 launches in 10 days). But it stages at about half the speed so F9R relies much more on the upperstage. I think with 5 merlin 1d trust level lox-lch4 engines the darpa xs-1 requirement of 3000-5000 pounds and 10 launches within 10 days could be reached. I'm not sure if a higher speed att staging is a better approach than what spacex has chosen for F9R. please comment how you think about this and if you have beter data about F9R to compare it with the requirements.
« Last Edit: 01/02/2016 04:21 PM by Rik ISS-fan »

Offline deltaV

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Re: Could a Falcon 9R fly to 100km altitude and land back?
« Reply #91 on: 01/02/2016 11:25 PM »
The requirements for Darpa XS-1 are:
- It should reach mach10,
- cost less than 5mln to launch. [Emphasis added by deltaV]
- can launch 10 times in 10 days.
- with an expendable upper-stage a payload with a mass between 3000-5000 pounds can be launched
Those cost and launch tempo requirements are roughly 10 times better than what Falcon can do currently. Maybe they'll get there eventually, but not in time for the XS-1 program I'm guessing.

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