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SpaceX BFR [video]

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211–220 of 277 posts

Re: SpaceX BFR [video]

#212

Cost per seat should be about the same as full fare economy in an aircraft. Forgot to mention that. - Elon https://www.instagram.com/p/BZnVfWxgdLe/ Looks like fun. I'd love to see the in-flight safety video! "Make sure there's nothing in your pockets because we'll be hitting 3 Gees. If anything goes wrong, we're all probably toast." I think this was just an interesting idea thrown out at the end of a talk that had mu…

Note that the Instagram post is a little misleading. “Full Fare economy” is not as cheap as you think, it’s more like what you would pay for business class. So, maybe $3k for a transatlantic flight.

True but its for a vastly superior service.

Re: SpaceX BFR [video]

#213
post #152

Earlier quoted context omitted.

If they build a rocket fuel plant on Earth the carbon footprint will be negative.

So a solar powered rocket fuel generator would be a carbon sink?

If all the carbon came from Earth and some is burned in space then the footprint on Earth is negative I think

Re: SpaceX BFR [video]

#215

Earlier quoted context omitted.

It would be different if this was coming from the mouth of the Comcast CEO but it's coming from Musk who has a series of successful achievements of his own, a profitable space company with the worlds first re-usable rockets, the first company to successfuly market an electric car, fastest growing battery storage solution on the market. These things matter.

They do, but the crux of every Musk fantasy is a radical drop in the cost of these things, a promise he has never delivered on.

Delta IV Heavy: ~450 million

Falcon 9: ~100 million

Re: SpaceX BFR [video]

#216

Earlier quoted context omitted.

Loss rate for space launches is largely due to the fact that the systems are essentially munitions (i.e. expendable, single-use) and flight rates are very low. Rocket failures for crewed rocket launches are extremely rare, occurring once every couple decades. It's hard to improve on that because low flight rates make data very hard to come by. Airplanes fail much more often in absolute terms, giving you a lot more da…

The problem is that to increase flight rates by 5 orders of magnitude, you need demand to increase by that much. And people are unlikely to demand rocket flights until after they're as safe as plane flights. Early passenger planes were pretty dangerous to, but they got around the above problem by a) being much faster than trains, making the risk worth it, b) having clear military applications, the military being less…

You answered your own question: military applications.

The US Armed Forces would pay a LOT of money to move 100+ tons of personnel and materiel anywhere on earth with a flat landing spot in under 60 minutes.

You could have tanks on the ground that were fully operational in under 3 hours (probably half that if they left the BFR packed and fueled for takeoff at all times), or a disaster recovery base set up within 24 hours of the winds dying down (to pick a more topical example.)

Re: SpaceX BFR [video]

#217

Earlier quoted context omitted.

The primary purpose of the cabin crew in an airliner is to handle emergencies. When SHTF, they'll figure out the right course of action, open emergency exits, and get people outside. I'm not sure if the BFR ship would have any emergency survivability. It looks to me like the sort of thing where the flight goes well or everybody dies. In which case, yes, no need for cabin crew! (And to be clear, I have nothing against…

An emergency landing on water followed by everyone exiting the vehicle and using their seat cushion as a flotation device seems like the obvious counterexample. That seems survivable enough (I bet that ship would float better than a 747) but you'd want people on hand to help everyone out.

I can't come up with a scenario where the BFR ship would make an emergency water landing. (Of course, it could just be that I lack knowledge or imagination.) Airliners can do them because they glide, so water landings are a possibility after fuel exhaustion or engine failure. BFR won't glide well enough to land softly, so it would have to be a propulsive water landing. And if you can land propulsively in the water, surely you can land propulsively at the landing pad.

Re: SpaceX BFR [video]

#218
post #124

Earlier quoted context omitted.

No more deep vein thrombosis. Or screaming kids kicking the back of your chair cause they've got nothing to do for 10 hours. London to Sydney would be a massive improvement because often you have to stop halfway. Plus you get all the benefits of paying for a Virgin Galactic trip

Auckland to Vilnius is at least 3 flights and 24+ hours of flight time. Door to door is basically 2 days. Elon please save me.

How often do you think you can find a rocket's worth of people who want to go from Auckland to Vilnius?

Re: SpaceX BFR [video]

#219

Earlier quoted context omitted.

The primary purpose of the cabin crew in an airliner is to handle emergencies. When SHTF, they'll figure out the right course of action, open emergency exits, and get people outside. I'm not sure if the BFR ship would have any emergency survivability. It looks to me like the sort of thing where the flight goes well or everybody dies. In which case, yes, no need for cabin crew! (And to be clear, I have nothing against…

An emergency landing on water followed by everyone exiting the vehicle and using their seat cushion as a flotation device seems like the obvious counterexample. That seems survivable enough (I bet that ship would float better than a 747) but you'd want people on hand to help everyone out.

The point is with a rocket, if you can't land at your original destination, you probably don't have the capability to safely land anywhere else. Maybe I'm overlooking a scenario you have in mind, but IMO you're looking at two classes of problems:

1) Problem during launch. There's been one successful use of a launch escape system in rocketry history[1], and such a system has never been developed for a shuttle type craft.

2) Problem after entering orbit. Cutting your orbital flight short isn't going to change the fact that you still have to survive re-entry stresses and have a working vertical landing system.

[1](https://en.wikipedia.org/wiki/Launch_escape_system#Usage)

Re: SpaceX BFR [video]

#220

I think if we measure the travel time from door to door the benefits of the fast rocket shrink in a relation to where is located. With airplanes this is solved, by the big infrastructure ( cities sometimes have even 2-3 airports ). Where I live ( Berlin ) with a flight to NYC would look like : 1. City center -> TXL - 20m 2. Check-in / security - 30m ( no joke, the airport is small ) 3. Flight - 9h 15m 4. Check-out /…

Wasn't the commute to and from the terminals also one of the things that killed the Hyperloop?

I believe the rumors of its demise are greatly exaggerated.
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