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SpaceX BFR [video]

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Re: SpaceX BFR [video]

#131

Post by ben_w »

jacquesm wrote: post #11
wayanon wrote: post #7

The security protections on the launch pads alone would have to be incredibly high. Looks vulnerable at sea like that.

Like the security precautions at airports? Any airport that I'm familiar with has access roads and roads around it that are accessible to the public from where any idiot with an RPG or possibly even a rifle could attempt to bring down a passenger jet. And yet it does not happen.

I wonder why it does not happen, given that terrorist attacks in general do occur. Great policing, or do the bad guys just lack imagination?

Hoping for the former, but if I were a civil servant I’d want to assume the latter and plan for surprise imagination.

Re: SpaceX BFR [video]

#132

Post by TremendousJudge »

giosalinas wrote: post #127
jokoon wrote: post #61

Aren't supersonic jets more affordable? I mean I know SpaceX is about changing the world, and I know SpaceX is about rockets, but in terms of market, I think having a new Concorde would better fit the idea of earth to earth travel. I like how SpaceX innovates, but I think this is a "too soon", bad product idea because it will be too expensive at first, and supersonic jets would be a better competitor. Although I have…

Aren't supersonic jets more affordable? - NO, end of story.

says who?

Re: SpaceX BFR [video]

#133

Post by Boothroid »

ben_w wrote: post #131
jacquesm wrote: post #11

Earlier quoted context omitted.

Like the security precautions at airports? Any airport that I'm familiar with has access roads and roads around it that are accessible to the public from where any idiot with an RPG or possibly even a rifle could attempt to bring down a passenger jet. And yet it does not happen.

I wonder why it does not happen, given that terrorist attacks in general do occur. Great policing, or do the bad guys just lack imagination? Hoping for the former, but if I were a civil servant I’d want to assume the latter and plan for surprise imagination.

There are tools available to help reduce the threat, e.g. http://www.cunningrunning.co.uk/sam-pras

'SAM-PRAS is a unique market-leading solution used by counter-terrorism agencies to identify potential MANPADS launch points within range of flight paths.'

I don't work for or have any association with this company BTW, just aware of their software.

Re: SpaceX BFR [video]

#135

Post by gbhn »

thinkcontext wrote: post #128
codeulike wrote: post #101

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…

It will have to do intercontinental cargo flights for a while before it can be FAA human certified. They'll probably need to invent whole new classes of safety requirements before it can take passengers.

To me this looked like it could be the key to the whole thing...

That is, the idea is that you build a high-speed airline with spaceports all over the world, refueled by huge solar arrays refining Ox and CH4 out of the air. Then it turns out your airliners, by virtue of the fact they are orbiters, can also launch satellites and go to Mars and other interplanetary destinations (where similar spaceport situations can be built).

The key to the whole thing is to make the second stage an orbiter big enough to do re-entry so the whole system is re-usable. Re-usable second stages are a giant pain, but if the secret is to get big, and that means you're kind of "accidentally" running an airliner, then perhaps SpaceX has found the right business model for commercial space flight in such high volume that things like going to Mars and asteroids and so forth are sort of on the cost order of chartering a private flight -- well within the reach of many organizations.

Re: SpaceX BFR [video]

#136

Post by madamelic »

ben_w wrote: post #131
jacquesm wrote: post #11

Earlier quoted context omitted.

Like the security precautions at airports? Any airport that I'm familiar with has access roads and roads around it that are accessible to the public from where any idiot with an RPG or possibly even a rifle could attempt to bring down a passenger jet. And yet it does not happen.

I wonder why it does not happen, given that terrorist attacks in general do occur. Great policing, or do the bad guys just lack imagination? Hoping for the former, but if I were a civil servant I’d want to assume the latter and plan for surprise imagination.

>Great policing, or do the bad guys just lack imagination?

Ease.

It is likely quite difficult to get an RPG without getting eyes on you, then driving to an airport with an RPG, then lining up a shot and hoping to hit a plane moving at 100+ MPH.

Or you can take a truck and drive it through a crowded mall.

Re: SpaceX BFR [video]

#137

Post by hossbeast »

awiesenhofer wrote: post #56
willyt wrote: post #53

Earlier quoted context omitted.

And if it becomes that common, in 150 years time, New York will be under water. I remember reading that the instantaneous power output of one Apollo rocket taking off is roughly the equivalent of the entire average electricity load of the UK. Surely burning a country's worth of rocket fuel every time you want to travel long distance is not sustainable?

Well, New York City probably will be largely underwater in 150 years anyways, but not because of the BFRs. SpaceX plans to synthesize the fuel by using water, solar power and captured carbon dioxide from the earths athmosphere - just like it will be done on mars.

Is it true that an extrapolation of existing trends puts NYC underwater in 150 years?

Re: SpaceX BFR [video]

#138

Post by simonh »

jokoon wrote: post #61

Aren't supersonic jets more affordable? I mean I know SpaceX is about changing the world, and I know SpaceX is about rockets, but in terms of market, I think having a new Concorde would better fit the idea of earth to earth travel. I like how SpaceX innovates, but I think this is a "too soon", bad product idea because it will be too expensive at first, and supersonic jets would be a better competitor. Although I have…

It’s a really good question. Supersonic jets were always heavily constrained due to noise pollution issues with the sonic boom. They weren’t allowed to fly over land at supersonic speeds, relegating them to trans-oceanic routes. Now yes this system will have such problems on launch, but as they go pretty much straight up out of the atmosphere compared to a jet, the vast majority of the journey is in space where that’s not a problem. Also supersonic jets had range restrictions preventing maximum use of their speed, while this thing can go literally anywhere on Earth. Finally the big killers with Concorde was recouping development costs and paying for ‘one-off’ spare parts, the costs were crippling. The BFR will (hopefully) exist anyway, so that’s not a factor.

In principle yes a supersonic airliner could be cheaper, but the noise pollution issue alone is one of those external factors that is a real killer. Now it’s quite possible this use of the BFR might run into issues like that of its own, but they’re likely to be different issues at least.

Re: SpaceX BFR [video]

#139

Post by hossbeast »

leonroy wrote: post #119
mtgx wrote: post #85

Earlier quoted context omitted.

Fusion power can't come soon enough. Maybe it's time for Musk to start working on that. He actually said in an older interview that he would like to tackle it eventually.

He recently said (paraphrasing) that it wasn’t particularly productive investing in Fusion when there’s a giant, very efficient fusion reactor in the sky. We’d be better off improving solar panel efficiency and energy storage solutions.

He's also said rockets are the only transportation where electric wont work.

Re: SpaceX BFR [video]

#140

Post by [deleted] »

jokoon wrote: post #61

Aren't supersonic jets more affordable? I mean I know SpaceX is about changing the world, and I know SpaceX is about rockets, but in terms of market, I think having a new Concorde would better fit the idea of earth to earth travel. I like how SpaceX innovates, but I think this is a "too soon", bad product idea because it will be too expensive at first, and supersonic jets would be a better competitor. Although I have…

[deleted]
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