totm nov 2023 SpaceX Discussion Thread

[PB666]

2 hours ago, DAL59 said:

It runs on methane, which isn't that hard to obtain.  

https://en.wikipedia.org/wiki/Bell_Boeing_V-22_Osprey#Specifications_.28MV-22B.29

It could carry 6 of them.  

Talk about something that would be completely useless on Mars (Insufficient pressure, no oxygen) or Venus (no oxygen, too hot for a turbo prop to function).

[tater]

4 minutes ago, PB666 said:

Talk about something that would be completely useless on Mars (Insufficient pressure, no oxygen) or Venus (no oxygen, too hot for a turbo prop to function).

This was related to military utility.

[StrandedonEarth]

Well, one BFR+BFS has a cargo of what, 150 tons? It could drop ten fifteen-ton reentry pods each containing an unmanned tank drone, without even needing to land near hostiles.

[CatastrophicFailure]

@Nibb31 @PB666 I can already think of one very specific situation on the other side of the Pacific right now where the need to rapidly deploy large numbers of special forces in a nearly un-interceptable manner might be useful. This is not to say that they wouldn't have support by other means, but it can be very handy to drop troops one place when you've got your adversary focused on another. 

We can what-if this all day, it's all speculation one way or another. I'm just saying, I can see how such a thing would be one possible reason why the USAF would be interested.

[sh1pman]

On 30.09.2017 at 3:12 AM, tater said:

P2P is more useful to the military than it will be for travel. Redefines "rapid response."

 

7 hours ago, tater said:

Point to point is not something of much utility to the military I think.

 

Edited November 20, 2017 by sh1pman

[tater]

The sortie timing more than anything else. P2P means you could fly from one USAF facility to another—overflying a target area while in space.

thats the P2P they would use, not landing in a hostile area, I’d think.

This allows single, unpredictable passes pretty much anywhere on Earth.

36 minutes ago, sh1pman said:

 

 

 

@CatastrophicFailure, that particular area is particularly mountainous. 

Overflight is a different issue.

[James Kerman]

I could also see a role in humanitarian missions.  Disasters are unpredictable and always require a rapid response.

[PB666]

Well if its a rocket you can launch it from Diego Garcia and you don't need BFR. You don't need to reach orbit. The US has bases in the Indian Ocean, in the Atlantic, at several points in the Pacific. There is no need for an 150 t payload to orbit.

One other thing, how are you going to load 2 tanks into a rocket in an emergency. It would be cheaper to take a used 747 from the desert and put two tanks in it, and land the 747 in another desert and roll the tank out wasting the 747.

This whole line of thought is silly and is about as off-topic as one can get while still mentioning something space X.

[softweir]

49 minutes ago, PB666 said:

Well if its a rocket you can launch it from Diego Garcia and you don't need BFR. You don't need to reach orbit. The US has bases in the Indian Ocean, in the Atlantic, at several points in the Pacific. There is no need for an 150 t payload to orbit.

One other thing, how are you going to load 2 tanks into a rocket in an emergency. It would be cheaper to take a used 747 from the desert and put two tanks in it, and land the 747 in another desert and roll the tank out wasting the 747.

This whole line of thought is silly and is about as off-topic as one can get while still mentioning something space X.

It would be even cheaper to use a couple of C-17s and fly them out after the drop-off.

[tater]

1 hour ago, James Kerman said:

I could also see a role in humanitarian missions.  Disasters are unpredictable and always require a rapid response.

It's not enough cargo to be meaningful in a serious disaster, and risks rather a lot, but as someone who watched the Thunderbirds back in the day, I don't hate the idea  

1 hour ago, PB666 said:

Well if its a rocket you can launch it from Diego Garcia and you don't need BFR. You don't need to reach orbit. The US has bases in the Indian Ocean, in the Atlantic, at several points in the Pacific. There is no need for an 150 t payload to orbit.

One other thing, how are you going to load 2 tanks into a rocket in an emergency. It would be cheaper to take a used 747 from the desert and put two tanks in it, and land the 747 in another desert and roll the tank out wasting the 747.

This whole line of thought is silly and is about as off-topic as one can get while still mentioning something space X.

Remember that BFS is a SSTO with a ~10 ton payload. That means TO and landing from any USAF base with methlox tanks pre-installed. Not to deliver tanks (which is absurd), but to overfly as a spy plane (or bomber, frankly). The payload could be larger without the SSTO requirement, so you could launch from say Australia, and land in the UK, overflying the sandbox area in a great circle.

I think this explains USAF interest.

[PB666]

BFS is the new ITS, similarly undefined thing.

[Nibb31]

You guys are forgetting that the lead time in "rapid response" isn't flight time. It's all the logistics that happen before and after the flight: deciding what equipment is needed, preparing, checking, and transporting the equipment to the staging base. This typically takes several days in the best cases because modern armies can't afford to have all their best equipment packed up in crates and ready to go. Then it's unpacking and readying the equipment and getting it to where it's needed in a hostile environment. The flight time is only a small factor here, and it is offset by the additional complexity of loading and unloading the top of a rocket instead of rolling it out of a C-17.

Edited November 21, 2017 by Nibb31

[Nibb31]

On 20/11/2017 at 1:51 AM, CatastrophicFailure said:

@Nibb31 @PB666 I can already think of one very specific situation on the other side of the Pacific right now where the need to rapidly deploy large numbers of special forces in a nearly un-interceptable manner might be useful. This is not to say that they wouldn't have support by other means, but it can be very handy to drop troops one place when you've got your adversary focused on another. 

For how long has that situation been escalating ? It has nothing to do with long range rapid response because US has been deploying forces in military bases and sending carrier groups in the area for months. In situations like these, the slow deployment of forces is actually useful because it puts progressive pressure on the opponent in diplomatic timescales.

If a conflict was to erupt, then forces could be flown in from Japan an South Korea in hours, but it would more probably be done by airstrikes from regional USAF bases and Navy carriers. They wouldn't fly in special forces from Fort Lauderdale on a rocket, because they are already in South Korea waiting for the word.

Landing a rocket full of special forces in Pyongyang would be a stupid idea. The rocket would be a sitting duck that could be taken out by an Soviet-era RPG or an AN-2, and the wreckage would also be a free technology boost for the North Korean missile program.

Quote

We can what-if this all day, it's all speculation one way or another. I'm just saying, I can see how such a thing would be one possible reason why the USAF would be interested.

It wouldn't.

If the military has an interest in BFS, its for its inspection and interception capabilities. This is something that the military has been working on for decades: the ability to rendezvous with hostile satellites, intercept or disrupt communications, and eventually disable the satellite if necessary. The BFS could even kidnap enemy sats and bring them back (not very realistic though).

Edited November 21, 2017 by Nibb31

[Josh IN SPACE]

I also think about launch delays. You have the ship ready to go for what's supposed to be a quick trip, when suddenly launch is scrubbed for the day/week due to unfavorable conditions. Those conditions might not be so unfavorable to the aircraft sitting on standby, and so everyone just loads up on the plane and makes it to the destination, albeit not as fast the rocket would have, but faster than the rocket now that it's delayed. 

[PB666]

4 hours ago, Nibb31 said:

If the military has an interest in BFS, its for its inspection and interception capabilities. This is something that the military has been working on for decades: the ability to rendezvous with hostile satellites, intercept or disrupt communications, and eventually disable the satellite if necessary. The BFS could even kidnap enemy sats and bring them back (not very realistic though).

Maybe.

A 90 lb robotic cube sat with a couple of solar panels and ION drive. http://www.busek.com/index_htm_files/70008514 RevD Busek Ion Thrusters.pdf on a metal cage with some solar panels.

How about sticking a insulate probe in the satellite and discharging 100 kV.

You could launch a 200 of these from an F9 and have them wandering LEO shadowing potential target ready to strike at a moments notice. 1/2 meter cubed, about the size of space junk. You could even give them a legit function of pushing bits of space junk into atmosphere intercepting orbits, with 8500 DV to play with they can pull themselves out many times.

placing a probe along a tangential surface and giving that surface 50 dV of thrust (uncontrollable spin). Then have a sophisticated computer that pulse thrust sending the satellite into the atmosphere.

Think of this something that clamps onto the satellite, then fills a large parachute shape plastic bag 100s of feet across with an aerogel increasing drag by 100 or 1000 fold and also drills a hole in the monopropellant tank.

 

[kerbiloid]

200 sats with ion drives, wouldn't this be too expensive for a short-living pack of junk pieces?

Spoiler

That sat with a horn reminds me of Nautilus with its ram.

 

[PB666]

Why short lived, xexon can be stored indefinitely (argon is a cheap replacement).

 

[Racescort666]

There was literally no mention of P2P in that article which was already very speculative to begin with. I suspect that Shotwell is on track with the Air Force being interested in having a gigantic rocket to play with and launch new payloads on:

Quote

Shotwell said after the talk that BFR could be used to launch some of the heaviest national security payloads envisioned by the Air Force in the 2020s.

“I do anticipate that there is residual capability of that system that the government will be interested in,” she said. “I do see that we would likely get some funding from the government for BFR and BFS.” 

And the fact that they have already received funding for Raptor development that has the following verbiage specifically mentioning EELV: https://www.defense.gov/News/Contracts/Contract-View/Article/1348379/

Quote

Space Exploration Technologies Corp., Hawthorne, California, has been awarded a $40,766,512 modification (P00007) for the development of the Raptor rocket propulsion system prototype for the Evolved Expendable Launch Vehicle program.  Work will be performed at NASA Stennis Space Center, Mississippi; Hawthorne, California; McGregor, Texas; and Los Angeles Air Force Base, California; and is expected to be complete by April 30, 2018.  Fiscal 2017 research, development, test and evaluation funds in the amount of $40,766,512 are being obligated at the time of award.  The Launch Systems Enterprise Directorate, Space and Missile Systems Center, Los Angeles AFB, California, is the contracting activity (FA8811-16-9-0001).

So Raptor being complete by April 20th of next year sounds exciting.

Also, in regard to other SpaceX happenings, what's the deal with the fairings? I don't see this holding up FH static fire but I'm hoping with fingers crossed that they launch when I'm down in Florida for New Years.

[CatastrophicFailure]

23 minutes ago, Racescort666 said:

Also, in regard to other SpaceX happenings, what's the deal with the fairings? I don't see this holding up FH static fire but I'm hoping with fingers crossed that they launch when I'm down in Florida for New Years.

Every day Zuma goes unlaunched pushes FH back another day, I would think. They can’t really work on the TEL while there’s a rocket sitting in it. 

[CastleKSide]

Is there a rocket still sitting on it? I thoight they had taken it down.

[CatastrophicFailure]

3 minutes ago, CastleKSide said:

Is there a rocket still sitting on it? I thoight they had taken it down.

It’s still (presumably) on the TEL tho, that’s also how they move the assembled stack between the hangar and launchpad. AFAK, it’s the TEL that needs the last few modifications for FH, which can’t be done when it’s in use or planned to be in use. 

[cubinator]

23 hours ago, CastleKSide said:

 

Would it even have the capability of landing on unprepared ground? Ie not on a foot of concrete?

Well, there's no concrete on Mars, so...

[Racescort666]

21 minutes ago, cubinator said:

Well, there's no concrete on Mars, so...

Yet...

The point remains that something will have to land on an unimproved surface.

[tater]

 

Edited November 20, 2017 by tater

[Brotoro]

I find myself displeased with this Zuma thing.

Edited November 20, 2017 by Brotoro