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Gwynne Shotwell: SpaceX's Plan to Fly You Across the Globe in 30 Minutes [video] (ted.com)
89 points by logancg 10 months ago | hide | past | web | favorite | 101 comments

Rocket based travel will never ever ever happen on a widespread scale simply because of the G forces involved. Passengers on an airliner will begin feeling uncomfortable at around 1.2 G's and > 20 degrees of bank angle. The thought of subjecting regular paying passengers to 3+ G's and a full 360 degrees of pitch/roll is absurd. It could definitely be a niche thing for people that are physically fit, but this just isn't the way to go for high speed transportation. More traditional airframes and scramjets are far more likely to make hypersonic travel a reality.

20 minutes of discomfort to save 12+ hours of flight time? Sounds worth it to me.

Sure, but will your grandma say the same? My point is that this will never be a normal every day thing for the masses like air travel today.

True, but I don't think BFR is ever meant for the masses. And airplanes, which are gentle but can be uncomfortable, are barely for the masses (in 2015 only 45% of Americans flew on a plane).


...only? that's a first world problem if i've ever seen one :)

haha well I meant only 45% of the population isn't really "the masses"

I'd argue that it is, that's almost half the total population and an even larger percentage of working age adults.

How many of that 45% took a first class or business class international flight?

My grandma isn't travelling on a plane 12 hrs to anywhere. Long haul travel is more for the youngish anyway (think baby boomers). And my parents would take a 30 minute roller coaster over a 12 hr flight even if that meant using a puke bag every time.

At the price point, I imagine it won't be as competitive as a business class fare, which 99% of people will choose over 30 mins of non-stop barfing. No?

If you can bear with modern air travel today, the process, the rush, the waiting, the hassle with luggage, and worst of all being cramped in little seats with hundreds of other people around for really long periods of time, then I think you will probably be able to handle the rocket. The devil is in the details though.

Regardless, not only do I think I would I appreciate the shorter, more violent flight more as I got older, I would also appreciate the roll of the dice that if anything goes wrong we just all die instantly. Not a bad way to go, really.

Ever been bobsledding? I question how well even a fit adult deals with G forces that high. I consider myself pretty fit, but I found my experience at 4Gs to be completely unexpected. I could barely keep my head out of my lap. Sure, it was fun, and I didn't die, but they would not let the elderly, those with spinal injuries, or pregnant women ride a bobsled even for 90 seconds.

To that I would say the G-force strength and direction should be predictable, known even when they are designing the seats before building the rocket. So the passengers should be in an optimal position where they don't need to hold up their heads against the Gs but are cradled by the seat. I think that is very different from the bobsled analogy where the G-forces are changing intensity and direction all the time and you are not in an optimal position.

If the G-forces are unpredictable, well something went really really wrong.

But you are probably right in that there will be more medical restrictions than there are now. But someone with a spinal injury, or who is very pregnant, or very weak from age probably isn't going to be flying in today's aircraft either.

> we just all die instantly

It's surprising (to me at least) that it's not always instant. For example on the space shuttle Columbia, the astronauts went unconscious after a few seconds as the spacecraft was tumbling and breaking apart [1] but it's plausible that they could have regained consciousness if they survived the violent episode inside the shuttle as it broke apart.

1. https://www.nytimes.com/2008/12/31/science/space/31NASA.html

Normal people won't be able to afford this. It will serve a small market of wealthy, willing, healthy people.

Don’t underestimate the discomfort of spending a dozen hours in economy class. I’d take the rocket ride every day and twice on Sunday over that, and I’m not terribly fond of crazy rides.

I'm guessing C-levels are going to start getting into shape if they have 20+ less hours on planes during their day.

You seem to underestimate how annoying modern air travel is, at least in America. One has to stand in at least 3 different lines (baggage, security, boarding) before getting on the plane. Whether in the terminal or on the aircraft, the seating feels like it was designed to be as uncomfortable as possible.

I imagine that there will be people willing to travel via rocket just because of the 3+ G's. And I'd take a 30 minute roller coaster ride over a 10 hr first class flight any time, all the time. Less time spent flying > comfort while flying. One immediate benefit is that one doesn't have to take a week or more off of work for intercontinental travel. Weekend jaunts to Pattaya or the Alps are possible when you aren't spending 20+ hours in transit.

I wonder if 3G's while lying on your back on a gel cushion isn't a lot easier to take than 3G's standing on your feet?

It certainly is more comfortable; is it more comfortable enough? I'm betting a lot of people would be fine with it.

> a full 360 degrees of pitch/roll

Can't this be somewhat alleviated with some sort of free 360 deg. rotating suspension of the passenger cabin? So that the G forces are at least pointing "down".

This may be a stupid question, but could people be put under for 30 minutes and just be woken up at landing?

So you'd need a licensed anesthesiologist monitoring every passenger? Sounds expensive.

It's a matter of monitoring and dosage. You can easily do mass scale sedation with proper monitoring and appropriate patient selection. If your BMI is over 25 or you have OSA, you wouldn't qualify. If you're healthy, fit, and consenting, you could be sedated for a long haul flight and have minimal hangover, perhaps even feeling rested.

No. General anesthesia is a risky procedure, requiring constant one-on-one monitoring by a anesthesiologist.

Sounds like an industry ready for disruption. If only these damn regulations weren't holding us back.

/s (sort of).

GE has been trying to disrupt anesthesia for quite some time:


Edit: Since its not obvious, they have some machines that can go in autonomous mode and alert the hospital if the patient needs an actual doctor to fix something.

Can you show me a GE product which doesn't need an anesthesiologist present at all times?

As far as I can tell, none of those devices acts autonomously or even close to it.

If John Glenn could do a Shuttle flight at 77, I suspect you're overstating the difficulties here. People voluntarily subject themselves to 3+ Gs and 360 degrees pitch/roll at amusement parks daily, with fairly minimal levels of physical fitness being required.

You know John Glenn's name precisely because he is exceptional. I would certainly choose the discomfort of a 2-minute roller coaster over the discomfort of a 2-hour commercial flight, but... a man who set milestones in American spaceflight and was trained by NASA for a shuttle mission is hardly the baseline.

John Glenn is an exceptional case however. His career was in rocket travel and experimental aircraft.

If the full 30 minute flight is like a roller coaster, I would be green by the time we got there and probably have a full puke bag. But I'd still prefer that to a 12 hr long haul flight in coach.

If you could afford flying on a rocket, I bet you can also afford flying first-class. Would that alter your preference?

The main thing I'm thinking of is noise pollution. You think living near an airport is loud? I cannot even imagine what living near a BFR spaceport would be like. For coastal cities maybe it would be worth it to build a landing pad on an ocean platform some miles out to sea, but what about for cities like Atlanta or Beijing? There's nowhere around them to build that isn't already a suburb.

Perhaps, but maybe the model ends up being only a handful of BFR ports on each continent. Would you fly 1 hour to Mojave so you could rocket to SE Asia and fly another 1 hour to Singapore? Sign me up!

Floating platforms do, in fact, feature prominently in their point-to-point travel concept video. No clue what they'd do for travel to, say, Denver or Paris.

I'd expect a city like Atlanta to be served by an off-shore landing zone, with high speed rail (hyperloop!) as the connection.

Atlanta is very open to running public transit lanes into the area and land acq is cheap OTP. /s

I think SpaceX should just sell this service to military clients. The other comments here are talking about noise pollution, G-forces, bank angles, and other negative downsides of the service. However, if you have a bunch of active-duty, trained personnel who need to get across the globe ASAP, this is something I could see the military paying for. Moreover, most bases are not directly next to large population centers, which helps with the noise pollution argument.

As a business model I think SpaceX should be a manufacturer and not in the transportation business akin to Boeing or Airbus. There is a ton of logistics involved in transporting people globally. Of course there is the safety issues as well.

Boeing (later United Aircraft) used to operate their own airline (later United Airlines). They also bought Pratt & Whitney, Hamilton Standard, Chance Vought, National Air Transport, and Pacific Air Transport. They were vertically integrated across the airline industry by the end of the 1920s.

This all culminated in the Air Mail Act of 1934 [1] which prohibited airlines and airplane manufacturers from operating under the same corporate umbrella.

It will be interesting to see where this ends up with SpaceX integrating the consumer facing airline operation with rocket manufacturing. Something commercial airlines are not able to do.

>> safety issues as well.

And vomit. 4+G on launch. Freefall during cruise. 5+ G on reentry. Give me the first class ticket on a BA flight any day.

That sounds amazing actually. As of today, I'd consider a few minutes of micro gravity to be a once-in-a-lifetime experience. If that ever becomes something you can experience for the price of an airline ticket, I'd consider the ride itself to be worth the price of admission all on its own.

Obviously not for everyone, but you don't really need to be able to service _everyone_ to be profitable.

You can do it today for the price of a reduced-gravity aircraft ticket (~$5,000, https://www.gozerog.com)

The vomit can be fixed by the standard issue vomit bag! \s

SpaceX already are in the transportation business...they launch payloads into space today. Boeing and Airbus are manufacturers of those payloads and aircraft and whatever else, but they don't routinely operate them.

Betting against Elon Musk is historically unprofitable but if there was one of those bets saying that SpaceX will never actually field this other than for PR purposes then I'd probably take it.

I'm glad Gwynne is talking about this rather than Elon as I always take what Elon says with a large grain of "execution" salt (as in sure you can do that but not when you think you can).

Things will be very different when BFRs are flying regularly. BFRs imply full reusability, and full reusability implies a short 'cycle' time, which implies a much greater earth to orbit capacity, with implies a greater supply and more reliability to orbit, which implies that it stops being crazy to require that you have three or four launches in a single year to get all of your "stuff" into orbit.

The logistics of space launch are still crazy. You can launch two rockets in a weekend using two launch pads but you can't yet launch multiple rockets a week from the same launch pad.

I think a major point that isn't being talked enough about in public (although I'm sure people in SpaceX have considered it before coming up with numbers) with the "point-to-point" transport system is simple demand-supply economics. Sure, let's say they can run 10 100-person flights per day from New York to Shanghai but do that many people even want to travel that route on that particular day?

More speculation here, I don't have any knowledge on the matter, but...

If the flight time drops from 12 hours to 30 minutes, and prices are in the same ballpark of $2,000, then there would be more demand.

The execs could all be in Shanghai for the board meeting and some of them could be back in NYC for dinner.

Not so, due to time zones. Although I fully realize that if you can rocket out, meet, and rocket back, and go to sleep in the same time zone you woke up in, it would be a very significant development.


a crown jewel of human innovation, used to make sure the plutocrats don't have to suffer from the terror of foreign 5 star chefs.

can We call it "The Integral" instead of BFR? [0]

[0] https://en.wikipedia.org/wiki/We_(novel)

This is going to be big with the crowd that has jumbo jets as a personal airplane.[1]

[1] http://www.businessinsider.com/boeing-747-8-vip-private-jet-...

How do you tell the difference between commercial scheduled rocket flights and incoming ICBM's?

The same way you tell the difference between commercial scheduled airline flights incoming kamikaze pilots?

Assume that there aren't commercial scheduled airline flights going straight through a warzone?

Assume there aren't commercial scheduled spaceline flights taking off from nuclear missile silos.

I haven't heard of missile defense systems that are capable of determining the origin of an ICBM while deciding if it should try and take it out.

Infrared boost phase detectors on satellites have been around since the 60s. The US and Russian detection systems, at least, certainly know the origin of any ICBMs. There's not many parties that don't have that data and also have counter-measures.

Heavy regulation and requiring all flights to be registered with NORAD with high precision, probably.

We'd also know where the launch comes from, and how many got launched.

Russia can already stick a nuke in a commercial airliner and set it off over NYC, if they want.

Presumably you see where they take off and where they are headed for its pretty straight forward. Current ICBM's seem to have "relatively" minor down range maneuverability so once you're ballistic you can plot a big circle of where you can land. Is that near a spaceport? cool. Is it near a missile silo? better check into it.

Bombers are the same way, there is nothing that prevents building a nuclear bomber in the shell of a 747 and calling it a cargo plane on its transponder.

Same way you differentiate between an airplane and an alien spaceship. One is common, the other is so absurdly rare its not even worth considering.

You just build second strike capabilities and call it a day. If {Russia, U.S.} gets off a first strike, then {U.S., Russia} can still get off a second strike, therefore neither will strike first.

Well, that's one option. Russia will need an early warning network to rival the American one either way, and given that and proper flight path registration... maybe there would be no confusion. Maybe.

Something like a rocket version of ADS-B that feeds to a central data collection point, from which nation-states that are nuclear powers (permanent UN security council members, for the most part) can receive a read-only data stream of rocket traffic.

Would require rockets with speed/altitude limit uncrippled GPS.

The ICBMs are usually not 9m wide, made of carbon fiber, carrying transponders, and making a gliding reentry.

What would be the environmental impact of ubiquitous rocket launches for business travel?

Not too huge. This person[1] did some math and found that a BFR trip across the world should take 40% to 240% as much carbon as a regular plane flight. For short trips this would be worse, though, because a plane's range goes up almost linearly with fuel use while a rocket's goes up much faster than linearly.

Rockets that use solid boosters like the Space Shuttle, SLS, or Atlas V do a good amount of ozone damage as they go up but the ozone damage from cryogenic propellants of the sort that a BFR uses is pretty small.


Also I'm not sure where SpaceX gets its methane from. If it's from above-surface sources wouldn't its net carbon contribution essentially be zero?

Did a little googling. Methane is primarily obtained from natural gas fields which are below ground. Atmospheric concentrations are relatively low (on order of parts per billion) although it is still an important greenhouse gas (30x more potent than CO2 per ton). There's a lot of ongoing research into generating CH4 from CO2 using renewable energy but it's relatively energy intensive to date.

So there’s noise pollution on a grand scale, it depends on natural gas extraction or a breakthrough in electrolysis, and it will produce CO2 when burned in flight. Great. It will also cost a fortune, and even SST isn’t viable, yet somehow this will be?

I could not be more skeptical.

Most people replies are focusing on carbon footprint, but it might also be worth considering noise (e.g. how does the sound of a rocket launching off the coast of California affect whales?) and any atmospheric perturbations caused by the rocket. Launches damage the ionosphere, which hasn't been an issue in the past because as far as we know the damage doesn't have a huge impact, and the ionosphere usually is back to normal within a few hours (or even less depending on trajectory and some other factors). If launches are happening every hour in the same area, that might cause some problems with things like radios.

Does it damage the ionosphere? According to what definition of "damage"?

I honestly don't know, so if someone can explain how it really is damage, please do so by all means. But despite some popular suppositions to the contrary, "affects" != "damage". I know it affects it, probably from the same article from a week or so back as you, but that doesn't mean it's "damaged".

I guess "damage" is a judgement call I'm not really qualified to make. Someone could probably make the argument that humanity can't "damage" a natural system because we're part of nature. When half the electrons disappear over a few thousand square kilometers, it's not inherently better or worse. It may annoy someone at Arecibo Observatory or a HAM radio operator or a GPS user, but maybe there's also some positive aspects of that temporary depletion.

Depends on how many. Flying airplanes is around 1-2% of our total CO2 footprint. Of course, for an individual, doing 1 intercontinental flight with a full plane is equivalent to months if not a year of driving a car to work every day, but in total, not many people fly.

Depending on the efficiency of the rocket and the reduced number of people doing this, the numbers shouldn't be that much higher.

That's not really the case. Per passenger mile commercial aircraft get ~70MPG with longer flights tending to have better fuel economy. The trend is really interesting: http://www.slate.com/content/dam/slate/articles/business/the...

So, they are actually very efficient transportation for long trips. Absolute worst case flying around the world is 24,901 mi which uses the same fuel per person as a 35 MPG car commuting 26 miles each way for one year.

PS: You can double check this by considering ~1/3 of the cost of a seat as being spent on fuel.

Longer flights have better fuel economy only in short range regimes where the BFR is definitely not a consideration.


Fuel economy improves at first due to reduced overhead of taxiing, takeoff, and ascent, but as you go farther the fuel consumption increases due to the need to actually carry the fuel.

Aircraft choice plays a role here. Airlines tend to use more efficient aircraft for longer flights.

Airlines use longer range aircrafts for longer flights. That should be obvious, shouldn't it?

Efficiency is one way to increase range. Wingtip devices can reduce drag by inhibiting vortex formation, however they increase weight so there is a minimum flight distance before they are a net gain. https://en.wikipedia.org/wiki/Wingtip_device

There is a tradeoff of needing carry more fuel over a portion of the flight, but the aircraft also spends a higher percentage of it's fuel on flying vs taxiing etc.

What is not the case? 1-2% of total CO2 footprint? That flying a full plane is equivalent to months if not a year of driving a nontrivial distance every day?

I'm not saying cars are more efficient. It's just that the distance travelled is huge when one uses an airplane.

Many people use more fuel in a month getting to and from work than a round trip NYC to London flight. It comes down to both distance and fuel economy with some commuters putting in over 1000 miles a week. The range for commuting fuel uses vs transatlantic flight is much wider than 10x months to year.

Pretty similar to the environmental impact of jumbo jets. A 777-200LR burns around 145.5 tonnes of jet fuel to transport around 300 people 15,800 km. That's 31 grams of fuel per passenger-km, about 86% of the fuel is Carbon so that's roughly 27 grams of Carbon emissions per passenger-km. A BFR/BFS contains about 3,240 tonnes of propellant and allegedly will be able to transport around 850 passengers up to 20,000 km. The oxidizer to fuel ratio of the Raptor engine is currently unknown but it's likely it's around 3:1, meaning that 1/4 of the total propellant is Methane while 3/4 is liquid Oxygen, giving 810 of Methane per trip, give or take. Methane is 75% Carbon so a BFR flight should produce roughly 608 tonnes of Carbon emissions, or 36 grams per passenger-km (30% more than a conventional flight, seemingly).

However, it's possible to generate Methane fairly easily using solar power, so such launches have the potential to be nominally carbon neutral with some investment.

The BFR runs on a mix of liquid oxygen and methane, according to Wikipedia.

Ignoring obvious scalability problems, wouldn’t it be possible to manufacture that with a pretty decent environmental footprint from various carbon neutral bio sources?

SpaceX plans to refuel the BFR on Mars with methane and oxygen produced via the Sabatier process and electrolysis [1]. They might do the same thing on Earth, even if only for the bragging rights of being carbon neutral.

[1] https://en.wikipedia.org/wiki/Sabatier_reaction#Manufacturin...

It will eventually be very low, much lower than planes. The same technology that is being developed to make propellant on Mars can be used on Earth to extract CO2 from the air and/or sea water. A few squared km of solar panels on floating structures can produce enough propellant for one BFR trip a day.

The same propellant (methane) can also be used on planes, eventually, so BFR will bring many technologies advances independently of the outcome of the project.

Much lower than planes nowadays*

Obviously planes in the future can use cleaner propellants too.

Does that mean no food, no snacks during the flight? That sucks.

There would be neither the time nor the inclination for food service. A non-trivial percentage of passengers will be dealing with nausea during the thankfully brief 0g float.

The entire flight would be around 30min. Short airline flights don't serve meals already.

SpaceX is promising something that is feasibly decades away?

Do people still believe in Elon? Or have we figured out these are advertisements.

He's not promising it. Despite the optimistic language, its a somewhat-realistic dream that he'd like to do and plans to work on. At least that seems obvious to me.

As far as timelines go, Gwynne Shotwell is in an entirely different class than Elon Musk. If you haven't watched the video, you should, there's some interesting tension going on between her and Elon.

If she says it'll happen in the next X years, I'll put it at a >75% chance of being accurate. If Elon said something like that, i'd put it at 33% chance.

>This is the only time I've out-visioned Elon ... I want to meet other people in other solar systems.

You're not out-visioning Elon; it's a petty attempt at one-upmanship. It just doesn't seem genuine. I want to meet people in other Superclusters. Now she's been out-visioned!

> it's a petty attempt at one-upmanship

Gwynne Shotwell is SpaceX's President [1]. She and Elon are on the same team.

[1] https://en.wikipedia.org/wiki/Gwynne_Shotwell

It was an attempt at humor. Take a deep breath and try to do something useful today.

> "it's a petty attempt at one-upmanship"

I think it was just a light-hearted joke.

Employee #7 at SpaceX didn't you hear? Relax, they're on the same team.

And a really interesting life story. I like how she randomly ended up in the job:


> Four years into the job, Shotwell had lunch with a co-worker who had just joined the then-startup company SpaceX. They walked by the cubicle of CEO Elon Musk. “I said, ‘Oh, Elon, nice to meet you. You really need a new business developer,’” Shotwell recalls. “It just popped out. I was bad. It was very rude.”

> Or just bold enough to capture Musk’s attention. He called her later that day in 2002 and recruited her to be vice president of business development, his seventh employee. She wrestled with the decision. “The history of startup rocket companies isn’t exactly great,” explains Hughes, SpaceX senior vice president and general counsel. “This was not necessarily the safest play.”

You will never meet anyone from another solar system. Even if we assume such life exists (it might or might not - either is extraordinary), there is every reason to believe it is far away. It would be extraordinary again if that life is close enough to earth that the round trip of a radio transmission is within a human lifetime. There are just a few hundred (I wasn't able to find an exact number) starts within 25 light years - 50 year round trip time for a radio signal. We know of hundreds of earth like planets, but only by a definition that includes mars which is pretty much dead.

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