totm nov 2023 SpaceX Discussion Thread

[CatastrophicFailure]

10 minutes ago, Kr0noZ said:

Isn't that a part of LA or something? Right next to LAX?
I don't see them being cool with dropping rockets on a massive city...

Dammit.  That’s what I get for posting before my morning energy drink. 

I meant McGregor, TX. 

[magnemoe]

4 hours ago, Kr0noZ said:

Maybe this is all barking up the wrong tree anyway.
Since that upper stage goes into some kind of orbit anyway, couldn't they have it come around entirely and, you know, "land" it properly, like, on land?

That would solve the sea water issue completely...
There's some nice large desert areas in the US where that wouldn't be so bad I guess.

Perhaps not even land, second stage is 4 ton, that make it plausible to snatch with an helicopter, you can unwind wire and brake that over some hundred meters to make it softer so max force on helicopter is 6-7 ton, think letting an large fish wind out your line then fishing. 
This is much like the ULA plan for reuse first stage engines. 
 

4 hours ago, tater said:

Wow, that's an interesting idea. The current model is that the recovery ship, Mr. Steven, has to chase down the chute and do some of the work. I'm unsure how accurate they can deliver a parachute. I wonder how big you could make a circus net?

You have some control of parachutes, precision landing is an sport for skydivers and bullet eye is 30 cm. 
US army has an system to automatically land supply drops using gps. Here the ship and the stage can talk and the ship can tell the stage to go on position the ship will be in at intercept. 

[cubinator]

You could almost put some small control surfaces and wheels on S2 and glide it onto a runway with a parafoil.

Somebody want to volunteer to give it a shot in RSS?

Edited April 23, 2018 by cubinator

[Wjolcz]

That joke about Elon lurking... Yeah, maybe somebody should link him this thread. Just in case. The SpaceX team and he probably know all this already but you can never be 100% sure, right?

A lot of these ideas actually make sense. Not sure how much payload would have to be sacrificed for this kind of recovery though. For FH it's clearly not a problem since it's crazy powerful. CRS missions would probably not be hurt that much either. If F9 is about to become even more powerful (Block 5) and it can RTLS during CRS missions then it should also be OK landing on the barge after delivering Dragon and S2 with extra "bounciness".

Edited April 24, 2018 by Wjolcz

[tater]

 

Starlink will cost ~10 B$ to deploy.

Inside fairing payload diameter 8m.

Her model for making P2P travel cost effective is rate of flight. Her statement was that the vehicle costs a little more than a huge airliner, and while an airline can fly NYC to Sydney once in a day or two (round trip), and they can fly several times a day with the same vehicle. I hadn't even considered that aspect (because turning a rocket around in a couple hours is not something in my head, lol). She said cost bestwen economy and business class (different than what Elon said)/

Edited April 24, 2018 by tater

[sh1pman]

6 hours ago, tater said:

 

Starlink will cost ~10 B$ to deploy.

Inside fairing payload diameter 8m.

Her model for making P2P travel cost effective is rate of flight. Her statement was that the vehicle costs a little more than a huge airliner, and while an airline can fly NYC to Sydney once in a day or two (round trip), and they can fly several times a day with the same vehicle. I hadn't even considered that aspect (because turning a rocket around in a couple hours is not something in my head, lol). She said cost bestwen economy and business class (different than what Elon said)/

So, when she said that they’re going to build bigger BFRs in the future, does that mean they may possibly return to the 12m ITS design? Keep BFR doing work in near-Earth space, and use the bigger ITS for interplanetary flights?

[sevenperforce]

9 hours ago, tater said:

Inside fairing payload diameter 8m.

Nice.

9 hours ago, tater said:

Her model for making P2P travel cost effective is rate of flight. Her statement was that the vehicle costs a little more than a huge airliner, and while an airline can fly NYC to Sydney once in a day or two (round trip), and they can fly several times a day with the same vehicle. I hadn't even considered that aspect (because turning a rocket around in a couple hours is not something in my head, lol). She said cost bestwen economy and business class (different than what Elon said)/

Sure, rate of flight is great and all, but it reminds me of selling lemonade at a loss and making it up in volume. If the fuel costs of a single flight approach the maximum possible revenue from a single flight, enhanced flight rate is hardly a help.

And is the market really big enough to support thousands of business-class-priced tickets between NYC and Sydney each day?

[Tullius]

9 hours ago, tater said:

Her model for making P2P travel cost effective is rate of flight. Her statement was that the vehicle costs a little more than a huge airliner, and while an airline can fly NYC to Sydney once in a day or two (round trip), and they can fly several times a day with the same vehicle. I hadn't even considered that aspect (because turning a rocket around in a couple hours is not something in my head, lol). She said cost bestwen economy and business class (different than what Elon said)/

A380 costs 500 million dollars, which creates a cost of 100,000 dollars per day, if you operate it for 20 years. On the other hand, the A380 costs 50$ per seat and hour, which makes it cost 300,000$ per day, if we assume 500 passengers and 12 hours of operation, i.e. the operational cost is what is dictating the price tag of a ticket. Doing more flights per day, reduces the former, but not the latter.

In short, it doesn't matter what the BFS acquistion costs are, but how much a single flight costs. If it is less than 150,000$ for 250 passengers, it is a win. If not, it is a loss, since, as Concorde proved, very few people are actually willing to pay a premium for faster flights.

[wumpus]

11 hours ago, tater said:

Starlink will cost ~10 B$ to deploy.

I expect that Verizon and Comcast (and other non-US communication companies) paid a lot more for the same volume of last mile (and last km) connectivity.  And Starlink has a much better idea of how many customers they can expect.  For a business project dreamed up to justify a Mars rocket, this one seems pretty good.  Not sure if you can round up 250 passengers for a single exorbitant intercontinental trip.

[tater]

4 hours ago, sh1pman said:

So, when she said that they’re going to build bigger BFRs in the future, does that mean they may possibly return to the 12m ITS design? Keep BFR doing work in near-Earth space, and use the bigger ITS for interplanetary flights?

Bezos and Musk (and now Shotwell) have all said something long known to be true. if the goal is building people stuff in space, then bigger is always better. Mass fractions can only improve so much, then the way to get big stuff to space, is to make a big enough rocket that the 3% that makes it to space is large. Bezos said that NG would be the smallest orbital rocket they ever build. So yeah, if they follow their stated goals, rockets can only get larger. propellant is cheap.

1 hour ago, sevenperforce said:

And is the market really big enough to support thousands of business-class-priced tickets between NYC and Sydney each day?

She said between coach and business. A flight from NYC to Sydney tomorrow is ~$1000 coach, and ~$4-5000 (on a decent airline) for business class (1 way). So $2500-$3000 via BFR. At 100 passengers, that's $300,000 a flight in revenues. They'd need reflights in the 1000s to be able to make money on that. She mentioned starting with 100 people, which is too low. The internal volume is large enough for A380 levels of people, all in economy sized seats (well north of 500 people), so they could get revenues way up. With just 100 people in those small seats (28 min flight doesn't need much), perhaps it might be possible to forego the booster, and fly the BFS as a single stage?

24 minutes ago, wumpus said:

I expect that Verizon and Comcast (and other non-US communication companies) paid a lot more for the same volume of last mile (and last km) connectivity.  And Starlink has a much better idea of how many customers they can expect.  For a business project dreamed up to justify a Mars rocket, this one seems pretty good.  Not sure if you can round up 250 passengers for a single exorbitant intercontinental trip.

Concorde was ~$6000 each way as I recall. Shotwell is talking half that price. For a 5-6 hour flight, cutting the time in half is not worth a 2X price increase. To cut a 20 hour flight to 30 minutes? I'd pay that, I hate long flights.

[sh1pman]

10 minutes ago, tater said:

fly the BFS as a single stage?

500 people with luggage will be something like 35-50t. Probably too much for single stage, NYC-Sydney flight. But transatlantic flights, with optimized engine setup (e.g. 5 SL and 3 Vac Raptors), IMO, can happen.

Edited April 24, 2018 by sh1pman

[tater]

With only 1 stage, they might be able to fly with fewer people since the prop costs would be substantially lower.

[Wjolcz]

Today workmen came and started installing fiber optics in the building I live in and it got me thinking if perhaps it's because of Starlink and if the company installing it is trying to get and keep as many customers as possible before Starlink becomes a thing. Not like I live in some remote place, but it feels like these kind of internet providers are at a boom right now.

Another boring story: three days ago I showed my friend the Starman video and the double booster landing. He literally said "but this is reversed" and when I told him it wasn't he was in shock. He didn't know it happened. Really reminded me of when I first saw a rocket come down and explode on the barge. Got used to seeing them landing but it's still something very unusual.

Edited April 24, 2018 by Wjolcz

[sevenperforce]

15 minutes ago, tater said:

She said between coach and business. A flight from NYC to Sydney tomorrow is ~$1000 coach, and ~$4-5000 (on a decent airline) for business class (1 way). So $2500-$3000 via BFR. At 100 passengers, that's $300,000 a flight in revenues. They'd need reflights in the 1000s to be able to make money on that. She mentioned starting with 100 people, which is too low. The internal volume is large enough for A380 levels of people, all in economy sized seats (well north of 500 people), so they could get revenues way up. With just 100 people in those small seats (28 min flight doesn't need much), perhaps it might be possible to forego the booster, and fly the BFS as a single stage?

I just don't see there being a market for 500 people all wanting to pay that kind of premium for international flights, no matter how brief.

And definitely not multiple flights per day. Are there really thousands of business-class travelers flying internationally every day between every major route?

 

[sh1pman]

2 minutes ago, sevenperforce said:

I just don't see there being a market for 500 people all wanting to pay that kind of premium for international flights, no matter how brief.

And definitely not multiple flights per day. Are there really thousands of business-class travelers flying internationally every day between every major route?

 

Doesn't have to be the same route multiple times per day. A single BFS can hop between major cities not too far from each other, carrying 100 or so people every time. 

[sevenperforce]

7 minutes ago, sh1pman said:

Doesn't have to be the same route multiple times per day. A single BFS can hop between major cities not too far from each other, carrying 100 or so people every time. 

Sure, just like regional jets do. But there is still a real volume issue.

[tater]

2 minutes ago, sevenperforce said:

And definitely not multiple flights per day. Are there really thousands of business-class travelers flying internationally every day between every major route?

Can't find numbers, but London to Dubai or Singapore is about 2 million passengers per year. That's 5-6000 flights, or about 13 a day. Delta has 28 1st class, and 220-something coach.on a 777. Looking at a few with business class, they have ~50 in business class, and 12 in 1st, then 250 in coach. If we call it 50 in some premium seating, then that's 650 a day from London to those distant places at insane prices.

British Airways has 72 people in premium seating on that aircraft (16 first, 56 business).

[sevenperforce]

5 minutes ago, tater said:

Can't find numbers, but London to Dubai or Singapore is about 2 million passengers per year. That's 5-6000 flights, or about 13 a day. Delta has 28 1st class, and 220-something coach.on a 777. Looking at a few with business class, they have ~50 in business class, and 12 in 1st, then 250 in coach. If we call it 50 in some premium seating, then that's 650 a day from London to those distant places at insane prices.

Maybe so, then.

[tater]

London to Singapore is ~$2500 business class, BTW. First is twice that (1 way).

I'd think you'd charge higher on BFS for windows, so 2-3 grand for regular, and charge business class for a window.

 

[CatastrophicFailure]

And static fire is in a week. 

 

[sevenperforce]

46 minutes ago, CatastrophicFailure said:

And static fire is in a week. 

 

IT'S HAPPENINGGGGGGGGGGGGGGGG

[tater]

Yeah, can't wait for block 5. Sad, it was supposed to have launched today...

ASDS landing, too (which apparently is easier on the booster than an RTLS landing).

[wumpus]

1 hour ago, tater said:

With only 1 stage, they might be able to fly with fewer people since the prop costs would be substantially lower.

The delta-v for a London-Sydney flight might as well be the same as to orbit.  NYC-China should need 90% of that.  NYC-Paris will be 75% (which  might get away without staging).

1 hour ago, tater said:

Concorde was ~$6000 each way as I recall. Shotwell is talking half that price. For a 5-6 hour flight, cutting the time in half is not worth a 2X price increase. To cut a 20 hour flight to 30 minutes? I'd pay that, I hate long flights.

If you have the opportunity to have a layover in orbit with the 20 hour flight replacement will you take it?  It will barely nudge the delta-v requirements...

PS: don't run out of ignition fluid...

Edited April 24, 2018 by wumpus

[sevenperforce]

3 minutes ago, tater said:

Yeah, can't wait for block 5. Sad, it was supposed to have launched today...

ASDS landing, too (which apparently is easier on the booster than an RTLS landing).

I wonder what that means, exactly. I think it means that given the choice between an RTLS landing and an ASDS landing on a high-margin mission, ASDS recovery is easier on the booster because it allows more propellant to be reserved for a longer, gentler single-engine landing burn. But maybe it has something to do with the stresses of a long-duration boostback burn.

[tater]

1 minute ago, sevenperforce said:

I wonder what that means, exactly. I think it means that given the choice between an RTLS landing and an ASDS landing on a high-margin mission, ASDS recovery is easier on the booster because it allows more propellant to be reserved for a longer, gentler single-engine landing burn. But maybe it has something to do with the stresses of a long-duration boostback burn.

Yeah, when I saw that mentioned somewhere, I was surprised. I think you are right about margin.