Why We're Not Going To See Sub-orbital Airliners

glowend writes: Sci-fi author Charlie Stross has an article about sub-orbital flight, and why we'll never see it as a common mode of transportation. Quoting: "Yes, we can save some fuel by travelling above the atmosphere and cutting air resistance, but it's not a free lunch: you expend energy getting up to altitude and speed, and the fuel burn for going faster rises nonlinearly with speed. Concorde, flying trans-Atlantic at Mach 2.0, burned about the same amount of fuel as a Boeing 747 of similar vintage flying trans-Atlantic at Mach 0.85 ... while carrying less than a quarter as many passengers. Rockets aren't a magic technology. Neither are hybrid hypersonic air-breathing gadgets like Reaction Engines' Sabre engine. It's going to be a wee bit expensive."

Stross also makes a more general proposition that's particularly interesting to me: "One of the failure modes of extrapolative SF is to assume that just because something is technologically feasible, it will happen. ... Someone has to want it enough to pay for it—and it will be competing with other, possibly more attractive options."

Comments

I think the thing being missed here

[Pikoro]

I think the thing being missed here is that people are in a hurry. If I can fly a 747 from Seattle to Japan and the flight takes 14 hours, I would pay more to be able to do it in 7. That's an easy choice. Time spent in the air is generally wasted time. Turn trans-Pacific/Atlantic into a weekend trip instead of the current 3 days of travel time and there's a market for it.

The futuristic prediction that it would be economical to take a sub-orbital flight from NY to LA is probably not going to happen, but for trans oceanic and/or China/Japan to Europe. Definitely a market there.

Re:I think the thing being missed here

[iluvcapra]

I think the thing being missed here is that people are in a hurry. If I can fly a 747 from Seattle to Japan and the flight takes 14 hours, I would pay more to be able to do it in 7.

Would you pay ten times more? That's the kind of factor you'd be looking at for that kind of speedup.

Re:I think the thing being missed here

[Nutria]

the flight takes 14 hours,

10 hours, nonstop.

Turn trans-Pacific/Atlantic into a weekend trip instead of the current 3 days of travel time and there's a market for it.

The Concorde turned a 6 hour flight across the Atlantic into a 3 hour flight. Why, then, was the Concorde economically unfeasible? Cost

Those sub-orbital flights will cost a lot more than the Concorde flights. People will say, "$1200 for a 10 hour flight, or $5000 for a 4 hour flight?" Sure, a handful will pick the $5000 ticket ($20,000 when you add in spouse and a couple of children) but most will say, "4 hours is not worth $15,200."

Re:I think the thing being missed here

[steveha]

I think the thing being missed here is that people are in a hurry.

I think you didn't read TFA. Relevant:

The VIPs are leaving the carriers, driven away by the security annoyances and drawn by the convenience of much smaller jets that come when they call.

For rich people, time is the only thing money can't buy. A [hypersonic aircraft] flying between fixed hubs along pre-timed flight paths under conditions of high security is not convenient. A bizjet that flies at their beck and call is actually speedier across most intercontinental routes, unless the hypersonic route is serviced by multiple daily flights—which isn't going to happen unless the operating costs are comparable to a subsonic craft.

I know that if I had the money, I'd prefer to fly by bizjet. If I'm 5 minutes late it is still there waiting for me, and it flies from where I am directly to where I need to go... that's pretty hard to beat.

And he's right that governments will get really nervous about hypersonic craft. As he says in TFA, the hypersonic flight could stick to its planned flight path and then deviate only for the last 20 minutes, and still be able to hit an arbitrary target. With less time to react to the threat, government will try to preemptively secure each flight, which means the already-inconvenient airport security will get even more inconvenient.

Thus his point that even if hypersonic airplanes were available to them, rich people would rather fly a subsonic bizjet with minimal hassles (and with Internet available during the flight) rather than get to an airport on time, wait in the security holding pen with all the other common horde, undergo intrusive security procedures, fly really fast to whatever hub airport the hypersonic flight goes to, and then likely have to travel some more to get to the actually desired destination.

Re:I think the thing being missed here

[iluvcapra]

I paid $100 for a 512MB compact flash card in late 2004, or $200 per GB. I just ordered a 32GB USB 3.0 flash drive for $13, or $0.41 per GB. A 500-fold decrease in cost in just 10 years.

Moore's Law does not apply to jet engines.

The affordability also hinges on income (productivity per person), which has more than doubled since the 1940s

Nominal income hasn't significantly changed in the US since 2000, and has only improved 20% since 1980 (that's less than 3% per year). Productivity has gone up but all the gains have accrued to the highest income percentiles. So you're right, somebody will be able to buy flights on the aerospike liner, but it's not going to be something that "people" do, it'll be for the rich.

Re:I think the thing being missed here

[DerekLyons]

And he's right that governments will get really nervous about hypersonic craft. As he says in TFA, the hypersonic flight could stick to its planned flight path and then deviate only for the last 20 minutes, and still be able to hit an arbitrary target.

So can subsonic aircraft. And that's setting aside his confusion (easily missed by uneducated readers) over the difference between a ballistic suborbital craft and a hypersonic aircraft. And overlooking his error in thinking a hypersonic vehicle can be diverted vast distances at the last moment - it can't, by about fifteen or twenty minutes before landing it's slowing and descending (if it hasn't already). Or, if it's ballistic, by the last minute it will take considerable amounts of energy to divert it any significant distance. Or his failure to grasp that no modern air traffic control radar depends on skin paint - it's all transponders (and thus you don't need the massive ABM radars he seems to think you do). Etc.. etc..

Or, in short, he's full of crap.

Re:huh?

[DarkOx]

Yet Concord no longer flies. They had a damn good safety record too. Its a little tough to compare because there were really only two airline operating them through most of there service life, but there was one major crash! One!

If anything the crash, made everyone wake up and realize the youngest of those birds was more than 30 years old. Which is pretty well EOL for airliners.

They stopped building them and they were only flying them because they had them, a sunk cost. The airlines recognized there in fact were not really enough rich people to sell tickets to such that they could be operated profitably if they had to pay for their own depreciation to enable purchase of a new bird. Either that or they figured if the charged what they would really need to not even the rich would bother.

No it was not safety that killed the Concord, it was cost and it was dead bird flying a long time before the accident in 2000.

Re:huh?

[Anonymous Coward]

Were you attempting to make some kind of joke? Because you just look like an annoying contrarian fedora clad loser.

Heinlein Win

[Anonymous Coward]

While Heinlein's juvenile fiction was, well, juvenile, I like that it at least played with the concepts of economics.

Re:huh?

[Aighearach]

Right, they no longer fly, but they flew for a long time and tickets sold well, right up until the end when renewed safety concerns led to the decision to retire them. They were never a big money-maker, but they were popular and commanded high ticket prices.

The reason they no longer fly is that they didn't make enough money to stimulate a new product generation, and the old product was retired after a long service life. They weren't getting safer as they got older, and after a crash there are expectations of design analysis, upgrades, etc., that would have been expensive and wasn't warranted for such an old aircraft.

People who read that as some sort of spectacular failure that would prevent interest, or imply lack of interest, in high speed flight, well, that is just silliness. It was clearly a successful craft, it flew full, and yet it didn't make a boatload of money. Lots of airlines around the world operate at a loss, that is actually normal for the industry and does not alone tell you if the airplanes they are buying are successful models or not.

You know what else we won't see?

[Anonymous Coward]

Private space tourism, Moon colonies, asteroid mining. Can we forget all this juvenile 1960s naive sci-fi crap already?

Re:huh?

[demonlapin]

SUV's are pretty fuel-efficient per passenger mile if you fill them up with people and stuff. They're just bad commuter vehicles.

All those suburban moms drive SUV's because it's a vehicle with a lot of utility - seats four in comfort, with plenty of room for luggage and supplies, plus you can use it for trucking things around. People buy cars to account for all their usage, not just the most common parts.

Re:huh?

[Hognoxious]

exponential

That word does not mean what you think it does.