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Why we're not going to see sub-orbital airliners

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Re: Why we're not going to see sub-orbital airliners

#31

Post by SideburnsOfDoom »

DennisP wrote: post #17
cryptoz wrote: post #4

The first reason is "because terrorism". It's difficult to keep reading, because the logic the author follows does not fit with the title or point the author's trying to make. This is a largely list of reasons why sub-orbital airliners aren't already common; it's got baseline assumptions that technology will not rapidly improve, that airports will not innovate, that passenger demand is static, etc. I don't understand…

I'm having a hard time seeing how suborbitals would be any better for terrorists. It's only going so fast and high when it's in the earlier stages of the flight, and at that point it'll be computer-controlled just like any orbital rocket. Maybe as it comes in to land it'll be controlled by a pilot on board, but by then it's going a lot slower. It also won't have the large tanks full of fuel that made the 9/11 impacts…

> Maybe as it comes in to land it'll be controlled by a pilot on board, but by then it's going a lot slower.

Are you sure about that? Landing from orbit consists mostly of deceleration. If you manage to skip that, it's as dangerous as a meteorite. Fuel tanks are not needed when you have sheer kinetic energy.

Re: Why we're not going to see sub-orbital airliners

#32

Post by cjcartlidge »

TheOtherHobbes wrote: post #19
cryptoz wrote: post #4

The first reason is "because terrorism". It's difficult to keep reading, because the logic the author follows does not fit with the title or point the author's trying to make. This is a largely list of reasons why sub-orbital airliners aren't already common; it's got baseline assumptions that technology will not rapidly improve, that airports will not innovate, that passenger demand is static, etc. I don't understand…

There are a lot of basic mistakes. 1. Concorde was on the verge of being replaced by a more efficient Model B version, which was quieter and cheaper to run. That was on the drawing board in the 1970s. Model C, D, E versions would have been cheaper and even more cost effective. 2. Concorde was actually killed by anticompetitive US politics. The story is too complex to detail here, but it's not a mystery in the aerospa…

"Concorde was actually killed by anticompetitive US politics." --> Any recommended reading for this?

Re: Why we're not going to see sub-orbital airliners

#33

Post by rdl »

For transpacific flights, first class (or business class, more often) is used by people who would otherwise be on business jets within the US. TBH, first class SQ Suites are nicer than any but the best business jets (I've never been on a really luxury jet like a 777 VIP, but I'd take SQ Suites over the G-II or Falcons I've been on). You're basically looking at $250k r/t SF-Beijing to take a Global Express or something. "Normal" business jets won't even get to Hawaii. I think things are different for transatlantic (esp if you're willing to stop somewhere like Canada or Ireland).

Business jets make actual sense when you're doing a multi-stop itinerary, lots of last-minute changes, and flying into secondary and tertiary airports. They make a lot less sense for hub to hub intercontinental flights.

You could solve all the security issues of intercepting a supersonic aircraft by having a failsafe override (optionally self-destruct). No need to build a Mach 5 interceptor when you can do it at c.

Re: Why we're not going to see sub-orbital airliners

#34

Post by jacquesm »

cjcartlidge wrote: post #32
TheOtherHobbes wrote: post #19

Earlier quoted context omitted.

There are a lot of basic mistakes. 1. Concorde was on the verge of being replaced by a more efficient Model B version, which was quieter and cheaper to run. That was on the drawing board in the 1970s. Model C, D, E versions would have been cheaper and even more cost effective. 2. Concorde was actually killed by anticompetitive US politics. The story is too complex to detail here, but it's not a mystery in the aerospa…

"Concorde was actually killed by anticompetitive US politics." --> Any recommended reading for this?

It's not exactly a fact. In my view Concorde was killed by a 'perfect storm': changing market conditions, 9/11, that terrible crash in Paris.

Together those three were what caused the towel to be thrown into the ring. Every time I visit Paris and I see it impaled on its stand it reminds me of a butterfly or something trying to escape. Such a sad image.

Re: Why we're not going to see sub-orbital airliners

#35

Post by kenrikm »

SideburnsOfDoom wrote: post #31
DennisP wrote: post #17

Earlier quoted context omitted.

I'm having a hard time seeing how suborbitals would be any better for terrorists. It's only going so fast and high when it's in the earlier stages of the flight, and at that point it'll be computer-controlled just like any orbital rocket. Maybe as it comes in to land it'll be controlled by a pilot on board, but by then it's going a lot slower. It also won't have the large tanks full of fuel that made the 9/11 impacts…

> Maybe as it comes in to land it'll be controlled by a pilot on board, but by then it's going a lot slower. Are you sure about that? Landing from orbit consists mostly of deceleration. If you manage to skip that, it's as dangerous as a meteorite. Fuel tanks are not needed when you have sheer kinetic energy.

Deceleration is going to happen regardless since you're coming down from much thinner air. The plane would most likely rip apart long before hitting said target, Mach 5 at Sea level does not do good things to airframes.

Re: Why we're not going to see sub-orbital airliners

#36

Post by GuiA »

jblow wrote: post #21

You can make a similar list about anything that doesn't exist yet. If it were easy, it probably would have been done. Eight years ago, you could have made an equivalent list about electric cars. Well, we have electric cars now and that situation is looking pretty good. Imagine you are an Elon-Musk-alike who wants to make fast air travel happen. Then this article isn't a list of why it's impossible, it is a list of pr…

Reminded of the Hamming quote:

If you do not work on an important problem, it's unlikely you'll do important work. It's perfectly obvious. Great scientists have thought through, in a careful way, a number of important problems in their field, and they keep an eye on wondering how to attack them. Let me warn you, `important problem' must be phrased carefully. The three outstanding problems in physics, in a certain sense, were never worked on while I was at Bell Labs. By important I mean guaranteed a Nobel Prize and any sum of money you want to mention. We didn't work on (1) time travel, (2) teleportation, and (3) antigravity. They are not important problems because we do not have an attack. It's not the consequence that makes a problem important, it is that you have a reasonable attack. That is what makes a problem important. When I say that most scientists don't work on important problems, I mean it in that sense. The average scientist, so far as I can make out, spends almost all his time working on problems which he believes will not be important and he also doesn't believe that they will lead to important problems.

Re: Why we're not going to see sub-orbital airliners

#38

Post by ghaff »

TheOtherHobbes wrote: post #19
cryptoz wrote: post #4

The first reason is "because terrorism". It's difficult to keep reading, because the logic the author follows does not fit with the title or point the author's trying to make. This is a largely list of reasons why sub-orbital airliners aren't already common; it's got baseline assumptions that technology will not rapidly improve, that airports will not innovate, that passenger demand is static, etc. I don't understand…

There are a lot of basic mistakes. 1. Concorde was on the verge of being replaced by a more efficient Model B version, which was quieter and cheaper to run. That was on the drawing board in the 1970s. Model C, D, E versions would have been cheaper and even more cost effective. 2. Concorde was actually killed by anticompetitive US politics. The story is too complex to detail here, but it's not a mystery in the aerospa…

A few additional points.

1. re: First class dying. The reason is that, aside from some of the really high-end international options on e.g. Emirates, business class has effectively become first class. In general, today's business class accommodations are significantly better than first class in the old days with lie flat seats and personal entertainment systems.

2. Concorde was always pretty much a niche market. Saving a few hours in a comfortable first class seat is not a big win for just about anyone unless you're a high-priced lawyer doing an out and back to London for a day.

Re: Why we're not going to see sub-orbital airliners

#39

Post by simonebrunozzi »

cryptoz wrote: post #4

The first reason is "because terrorism". It's difficult to keep reading, because the logic the author follows does not fit with the title or point the author's trying to make. This is a largely list of reasons why sub-orbital airliners aren't already common; it's got baseline assumptions that technology will not rapidly improve, that airports will not innovate, that passenger demand is static, etc. I don't understand…

Air travel is already terrible. No real improvement in the last 40 years. Flight times have actually increased (to save on fuel), and airlines are playing the trick of "let's make posted flight times longer than needed, so most of our flights we'll land in time".

Re: Why we're not going to see sub-orbital airliners

#40

Post by SideburnsOfDoom »

kenrikm wrote: post #35
SideburnsOfDoom wrote: post #31

Earlier quoted context omitted.

> Maybe as it comes in to land it'll be controlled by a pilot on board, but by then it's going a lot slower. Are you sure about that? Landing from orbit consists mostly of deceleration. If you manage to skip that, it's as dangerous as a meteorite. Fuel tanks are not needed when you have sheer kinetic energy.

Deceleration is going to happen regardless since you're coming down from much thinner air. The plane would most likely rip apart long before hitting said target, Mach 5 at Sea level does not do good things to airframes.

So all possible descent speeds are either

1) slow enough to be relatively safe

or

2) fast enough to cause disintegration of a craft designed for atmosphere re-entry.

I have no aerospace knowledge, so in the absence of anyone doing the maths, I'm going to go with "maybe so, maybe not".

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