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There is definitely a market for this. When you hit really high levels of the corporate or governmental world, time becomes enormously more valuable than money. The market might bear a cost many times that of a private jet flight if the time were this short.

This is an incredible idea for subsidizing the Mars rocket program via rapid transit for executives, heads of state, etc.

Of course it would also have to be demonstrated to be at least as safe as air travel first before it would hit the mainstream in that market.

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As I recall, that was the justification for Concorde. The market said otherwise, and that was before video conferencing had become too cheap to meter.

Concorde was run at a significant profit for years. R&D costs where not recuperated, but that that's just a question of scale.

It was in fact the justification for the first commercial airplane travel in general. Initially only well off people traveled by commercial passenger plane. It was extremely dangerous and very uncomfortable.

Fortunately we didn't stop our pursuit of progress due to such challenges. Now 3.5 billion or so passengers take extraordinarily safe, comfortable flights every year.

Concorde is about 4x faster than an airliner with a fairly limited range. BFR is 10x faster with global range. The point being that you can do 10x the trips and make 10x the money compared to airlines. Plus there's no taxiing around an airport. It's purely refuel and go.

Even if my numbers are out Concorde was borderline viable and BFR should be more capable of bringing in money.

Plus you go into frigging space. Branson wants to sell just that, this gets you into space and down to China.

Another advantage I can think of over Concorde is that there should be more space and the trip is only ever 30-40 mins, so no cramping up in the seat.

Finally a Concorde ticket was about $12,000, BFR was mentioned to be $1-2k at the end of the video.

That ticket price is definitely relevant. For some reason I thought Concorde was “only” $2500.

However, your point about cramped space made me realise that although the BFR isn’t going to be volume limited, that’s because it’s mass limited. Every 10kg of luggage will add about $250 to the price.

I have yet to see any mention of how the passenger experience is going to be. I assume it is much worse than some ear pain on take off and landing. Can the average person handle this trip comfortably? Or do they have to pass some astronaut-like conditioning test?

> Or do they have to pass some astronaut-like conditioning test?

I wonder about military applications. One would imagine that special forces groups would meet requirements. Being able to move SEALs around the world in a matter of minutes would be a boon for force projection.

Rocket launches take a certain amount of planning and favorable weather. Plus, they are impossible to hide. All in all, not desirable.

Ah, I forget that rockets are no where close to planes...

At best one could maybe speed up pre-planned movements, as opposed to allowing a QRF to more rapidly react.

Some of the things Burt Rutan has said over the years imply that this niche is already filled.

Forget about comfort. Rocket engines are dangerous and unreliable compared to planes and any other mode of transportation. People aren't going to tolerate the risk.

>Rocket engines are dangerous and unreliable compared to planes

To be fair, that's the problem they are trying to fix. This is like telling Microsoft that personal-computers will never work because they are big, expensive, difficult to use, and crash all the time.

To be fair, only half of those statements have changed. Computers still crash all the time, just less frequently than they used to.

But there's a magnitude difference there from "the early days".

Plane crashes still happen too, but with significantly less frequency.

>Computers still crash all the time

My personal XP is 20 years my computer crashed 1-5 times a day, now days my computer crashes maybe once every 4-6 months. That is considerable.

In general if your PC crashes you don’t explode though.

But now we have computers running our planes, running our cars, running our pacemakers.

Your PC might not kill you, but the software running the drive-by-wire system in your car will.

Still, my point wasn't to get into a discussion about the differences between software and rockets, but more to point out that their goal is to change those things about rockets. To make them reliable, safe and cheap.

You can think they won't be able to pull it off, but saying that it will never work because it doesn't currently work that way seems a bit silly.

> This is like telling Microsoft that personal-computers will never work because they are big, expensive, difficult to use, and crash all the time.

That's not a fair comparison. The energy difference between a rocket engine and an airplane combustion engine is huge. Rockets are all about raw energy output and are essentially a bomb. The fuel is volatile, and rockets use a lot more fuel than planes. If a failure happens with rockets, the whole thing usually ends up blowing up catastrophically.

Rockets are inherently more dangerous. But hey, more power to them. I would love it if we can make rocket flight safe enough for everyday use by everyone.

Assuming 1) a trip is about 10,000 miles in distance, 2) acceleration is constant and speeding up for 15 minutes and slowing down for 15 minutes, they are looking at (very roughly) 0.4g of additional acceleration i.e. you would feel 1.4 times as heavy as you do standing still on takeoff and landing. As you angled horizontally, the effect of earth's gravity would be counteracted by your centripetal acceleration so that you would feel approximately 0.4g at the midpoint of the flight. So 1.4g at takeoff and landing, 0.4g at the midpoint (again assuming constant acceleration due to thrust)

That sounds not too bad. Two 15 minute burns sounds in the realm of possibility.

Edit: changed some numbers and my conclusion.

There was some analysis on the SpaceX subreddit saying the G loads would peak out at 4 Gs. So a bit worse than those carnival rides where you stick to the pads on the periphery of a spinning room, which IIRC are only 3 Gs. With a well padded reclining seat it should only be mildly unpleasant for healthy adults but I worry that there are potential customers who won't be able to deal with it.

While I agree with you that there's a desire for this I'm not yet convinced there's a market for it.

As you say, this needs to be proven to be at least as safe as air travel.

Beyond that, for certain wealthy individuals, government dignitaries and the like commercial flight represents an unacceptable risk and cost in time eg Apple's board requires Tim Cook to fly private now.

Next, if the launch and landing pads are indeed offshore and otherwise remotely, this adds travel time at either end.

Also, rockets are subject to weather much more than planes are. If your landing pad is offshore then those weather effects are more pronounced as you have to deal with sea conditions too.

Lastly, current SpaceX landing is a "dead stop" approach (vertical velocity is designed to hit 0 when altitude is 0), which seems like it may not have the safety margins for mass transit. Future designs may of course improve on this.

So much as we'd like this, I'm not yet sure how we get there. Planes have to log many thousands of hours to be certified for passenger flight. Will we have enough launches to certify rockets this way? Even reusable rockets are, in comparison to planes, expendable because they're combusting huge amounts of fuel. Like I don't see you reusing the same rocket every day for 30 years like you can with a plane.

I don't understand your point about dead stop approach. What would be the alternative?

It's an issue of safety margins. Just consider the airplane.

- A two-engine plane can operate on just one engine

- In the event of losing power or losing both engines, a plane has a certain glide capability

- Runways are built allowing a certain amount of overshooting

- A bad approach allows you to circle back around and try again

- Planes can land and takeoff with significant winds and precipitation (including cross winds)

- A plane can actually land in a body of water (as happened on the Hudson).

Now compare the safety margins for a dead stop rocket reentering from space at Mach 30.

To address your first point - the rocket has 3 sea-level engines on the spaceship stage, each of which has enough thrust to land the ship on its own if the other two fail. (This is partly a byproduct of it being much lighter during landing than takeoff as most fuel has already been burned.)

I think the issue with the current hoverslam solution is that the timing of the rocket relight is critical to the rocket hoverslamming (and not just regular slamming). I don't have the answer to this but imagine that if an engine fails to relight at the correct time there's a much smaller (or maybe non-existent?) margin of error.

A plane on the other hand has two engines and can also generally just glide to the ground in the event that neither of them are working.

>time becomes enormously more valuable than money

In some sense this is true, but keep in mind you're not actually creating more time -- time spent on business jets can be quite productive, in-person encounters are not always necessary, and it is often possible to use scheduling to get two powerful people in a room together when they happen to be near each other anyway.

Also not sure if the video goes into this, but rocket launches are LOUD, and so tend to be away from densely populated areas -- plan on another 20-30 minutes on each side to get to/from the pad.

(Maybe tunnels will help with this? Load yourself into a tunnel pod, which then gets robotically loaded on the rocket, so door-to-door transport? Man, the future's gonna be sweet!)

20-30 minutes for checked luggage. 20-30 minutes for security groping. 20-30 minutes waiting for that idiot to find his seat. 20-30 minutes waiting for luggage or the carousel.

Putting on a pressure suit, guaranteeing your body can handle 5-6 Gs sustained for a few minutes, having a death rate of 1.5 percent.

Flying a VIP (semi-private) airline avoids all of this, and surely anyone that would take a rocket is already flying a fully private airline.

Using this as an example because I make this trip often: I can fly Cincinnati, OH to Charlotte, NC on a VIP airline for $500 round trip. I drive my car right up to the plane, and there is a rental car waiting for me at the plane exit on the other side. The entire plane is first class only. There is no baggage check, no TSA, no nothing. I can walk on to the plane 5 minutes before takeoff.

I am still awaiting a day when you can be projected anywhere and acceptance of it as a means of face to face. The old hologram style of science fiction interaction.

You're thinking like a technical person. The management caste needs face to face time, in person, where you can get social cues. Drinks, meals, walks together, golf games. Not Facetime or Skype.

Don't forget the girly bars. Never forget the girly bars.

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