New Armstrong speculation thread

[sevenperforce]

3 minutes ago, Bill Phil said:

BFR is already this, at least the booster is...

31 engines. More than N-1.

Obviously, haha. I meant, is the NA going to be a megacluster?

[Bill Phil]

1 minute ago, sevenperforce said:

Obviously, haha. I meant, is the NA going to be a megacluster?

We have no information on the vehicle, so I can't tell you.

[NSEP]

Just now, sevenperforce said:

Obviously, haha. I meant, is the NA going to be a megacluster?

I think so, the greater the amount of engines, the less an engine failure would matter. Right?

That is, unless you are fighting someone who is way in front of you, and you just think it has to be done, quick. *Cough* N-1 *Cough*

4 minutes ago, Bill Phil said:

We have no information on the vehicle, so I can't tell you.

Indeed, all we have is the name and an ''Its gunna be huuugee''

[sh1pman]

1 minute ago, NSEP said:

Indeed, all we have is the name and an ''Its gunna be huuugee

BFR gonna be like: do you even refuel, bro?

[NSEP]

1 minute ago, sh1pman said:

BFR gonna be like: do you even refuel, bro?

If NA can't refuel its going to be useless. Heck, even ULA is working on a refuelable upper stage !

[sh1pman]

2 minutes ago, NSEP said:

If NA can't refuel its going to be useless. Heck, even ULA is working on a refuelable upper stage !

Yeah, refueling is a great way to cheat the rocket equation. If Bezo is serious about his Moon colony plans, he needs to figure out the automated refueling.

Edited March 20, 2018 by sh1pman

[Canopus]

Just now, sh1pman said:

Yeah, refueling is a great way to cheat the rocket equation. If Bezo is serious about his Moon colony plans, he needs to figure out the automated refueling.

They said that Space tugs are something they want to do. And that would have to involve refueling.

[DAL59]

What if its 7 meters, and very tall?  Or three first stages strapped together?

[sevenperforce]

11 minutes ago, DAL59 said:

What if its 7 meters, and very tall?  Or three first stages strapped together?

Much taller than New Glenn, and you get into stability problems due to fineness ratio. Not to mention not having enough surface area on the base for engines. 

I doubt they'd do a New Glenn Heavy...or if they did, I doubt they'd call it a New Armstrong.

[hms_warrior]

It's funny that they talk about their second orbital-class rocket before their first had even a test-fire...

[tater]

1 hour ago, hms_warrior said:

It's funny that they talk about their second orbital-class rocket before their first had even a test-fire...

Given development times, and competition, they have to be thinking about their next steps years in advance.

[NSEP]

 I think it is possible for the NA to be a high-mass lunar lander, and not a launch vehicle. The BE-3 doesn't have a very high thrust, unlike the Raptor. So if they had a heavy lander that uses one or two BE-3 engines (maybe with a couple of reserves just in case) they could gently land on the Moon, like the Apollo LM, unlike the BFR wich has a thrust too high to do a gentle landing, and thus has to do a suicide burn instead..

4 hours ago, hms_warrior said:

It's funny that they talk about their second orbital-class rocket before their first had even a test-fire...

Even when you are just out of the water, you still want to plan ahead into the future. If this wasn't the case, development would be slower and the future uncertain.

[sevenperforce]

16 minutes ago, NSEP said:

 I think it is possible for the NA to be a high-mass lunar lander, and not a launch vehicle. The BE-3 doesn't have a very high thrust, unlike the Raptor. So if they had a heavy lander that uses one or two BE-3 engines (maybe with a couple of reserves just in case) they could gently land on the Moon, like the Apollo LM, unlike the BFR wich has a thrust too high to do a gentle landing, and thus has to do a suicide burn instead..

Elon said the moon landings would be set up for direct ascent returns, so they'd have substantial propellant reserves on landing. The BFR should be able to downthrottle its core engines enough to hover, even on the moon.

[NSEP]

3 minutes ago, sevenperforce said:

Elon said the moon landings would be set up for direct ascent returns, so they'd have substantial propellant reserves on landing. The BFR should be able to downthrottle its core engines enough to hover, even on the moon.

Scott Manley said otherwise, i think.

Skip ahead to 11:34

[sevenperforce]

8 minutes ago, NSEP said:

Scott Manley said otherwise, i think.

<snip>

Skip ahead to 11:34

Manley is great, but this seems like a bit of an offhand comment that wasn't thought through. Getting from the lunar surface back to Earth entry requires about 3 km/s if you're going to do a propulsive landing once you arrive. Dry mass of the Spaceship BFS variant is about 85 tonnes. If we suppose 10 tonnes of payload (which is probably conservative) and we assume 360 seconds of isp on the engines (since you won't be using the vacuum Raptors the whole time), you'd need to have 127 tonnes of propellant onboard at lunar touchdown.

Lifting 222 tonnes on the moon with a TWR of 1 requires 360 kN of thrust. Each of the three SL Raptor landing engines on the BFS has a vacuum thrust of 1900 kN. They can also all vector through the CoM independently. So if they can throttle down to around 20%, they can hover. I think 20% is the deep-throttle rating of Raptor.

[NSEP]

4 minutes ago, sevenperforce said:

Manley is great, but this seems like a bit of an offhand comment that wasn't thought through. Getting from the lunar surface back to Earth entry requires about 3 km/s if you're going to do a propulsive landing once you arrive. Dry mass of the Spaceship BFS variant is about 85 tonnes. If we suppose 10 tonnes of payload (which is probably conservative) and we assume 360 seconds of isp on the engines (since you won't be using the vacuum Raptors the whole time), you'd need to have 127 tonnes of propellant onboard at lunar touchdown.

Lifting 222 tonnes on the moon with a TWR of 1 requires 360 kN of thrust. Each of the three SL Raptor landing engines on the BFS has a vacuum thrust of 1900 kN. They can also all vector through the CoM independently. So if they can throttle down to around 20%, they can hover. I think 20% is the deep-throttle rating of Raptor.

Okay, makes sense, assuming the BFR is even heavier with extra fuel for return and a payload.

The only problem with BFR doing Moon missions now is ISRU and its Methalox fuel. Methalox is way harder to get on the Moon than Hydrolox. So you can't really push Lunar colonization to the max with BFR. It would make sense for New Armstrong to go for Hydrolox instead, considering its easier to get on the Moon.

[tater]

The Moon will not be colonized. Gravity is too low. BFS can do a round trip, no need for isru.

[Canopus]

8 minutes ago, tater said:

The Moon will not be colonized. Gravity is too low. BFS can do a round trip, no need for isru.

Mars won't be colonized either, at least not before the bone loss problem is solved anyway.

[NSEP]

10 minutes ago, tater said:

The Moon will not be colonized. Gravity is too low. BFS can do a round trip, no need for isru.

I agree, but instead, they want to colonize it anyways.

[sevenperforce]

17 minutes ago, tater said:

The Moon will not be colonized. Gravity is too low. BFS can do a round trip, no need for isru.

But it's so damn close.

[NSEP]

3 minutes ago, Canopus said:

Mars won't be colonized either, at least not before the bone loss problem is solved anyway.

Heck we don't even know if the bone loss problem exist in lower, (NOT ZERO/MICRO) gravity conditions yet (although it is likely it will be a problem).

Wait, who mentioned the colonization of Mars here again?

[Canopus]

1 minute ago, NSEP said:

I agree, but instead, they want to colonize it anyways.

You don't need people constantly living on the moon to utilize it's resources. And the short trip time also makes it likely that people could actually move back and to the moon more than once in their live.

[NSEP]

Just now, Canopus said:

You don't need people constantly living on the moon to utilize it's resources. And the short trip time also makes it likely that people could actually move back and to the moon more than once in their live.

True, say that to Jeff Bezos, im not wanting humans to colonize Luna.

[Canopus]

1 minute ago, NSEP said:

True, say that to Jeff Bezos, im not wanting humans to colonize Luna.

I don't think he explicitly want's to colonize Moon in the same sense Musk wants to do Mars. I think his idea is to drive or be part of the new cislunar economy. 

[NSEP]

Just now, Canopus said:

I don't think he explicitly want's to colonize Moon in the same sense Musk wants to do Mars. I think his idea is to drive or be part of the new cislunar economy. 

Maybe that is the case, although there are some sources that say Jeffy wants a permanent base on the surface of the Moon. Jeffy probably wants to build Moon hotels and science bases.