7 ms·

Previously Boom's CEO said this: “That’s not travel, that’s like a thing you might hope to do once in a lifetime,” says Scholl, before adding, “Versus where we

Previously Boom's CEO said this: “That’s not travel, that’s like a thing you might hope to do once in a lifetime,” says Scholl, before adding, “Versus where we want to get, which is anywhere in the world in four hours for 100 bucks.”[1] Anywhere in the world in four hours for $100 USD really caught people's imagination and attention. I'm puzzled by how they will achieve this. [1] https://www.cnn.com/travel/article/boom-supersonic-four-hours-100-bucks/index.html https://www.cnn.com/travel/article/boom-supersonic-four-hour...

wraptile 2y ago
> which is anywhere in the world in four hours for 100 bucks That's while my tesla robotaxi is making that 100 bucks driving leprechauns to their golden pots! Totally not vaporware guys.
hnuser123456 2y ago
Huh. The longest flights are around 10,000 miles. They usually cost over $1000. Fuel apparently accounts for about 25% of ticket price on long haul, so $250 in fuel normally. To do that in 4 hours is to travel 2,500 mph. Naively, traveling twice the speed requires 8x the power, so going over 4x the usual 550mph should mean over 64x more fuel burn, or $16,000 in fuel alone. Maybe a bit less since drag doesn't grow quite as quickly above transonic, call it $10,000. But if a ticket's only $100, I guess they've figured out how to get gas for 0.25% of typical prices.
- Ajedi32 2y ago
  Once you get out of the atmosphere, drag (and fuel consumption) is ~0. So theoretically possible, but I'm not sure if that's what he was talking about. Certainly Overture won't be capable of that.
  - hnuser123456 2y ago
    Fair, I hadn't considered the intercontinental ballistic passenger missile approach.
    - dylan604 2y ago
      Isn't that specifically one of the types of travel predicted to be made possible by reusable rockets capable of landing on the ground? From Florida to Japan in 45 minutes type of thing
      - adastra22 2y ago
        Yes point to point travel was a market for Starship. I think they’ve mostly backed off that though, as Starlink offers an easier market opportunity and just as much revenue potential. The supersonic plane would have advantages over the rocket approach though. Rockers require long, inconvenient transfers to offshore launch facilities. (But would have the selling point of a microgravity transit.)
      - notahacker 2y ago
        Reaction Engines in the UK spent over 35 years working mostly on that concept (though when they eventually went bust trying to scale up last year I think they were focused on reusable space launch business model which is ironically more realistic)
        ballooney 2y ago
        No, they were working on the latter (skylon) most of the time, though the new management that came in after their £60M investment quickly dropped SSTO in favour of more immediate RoI applications. The passenger plane was LAPCAT which was a paper study commissioned by the EU. They did some interesting real work too, such as designing and testing a hypersonic engine combustion chamber that could reduce NOx emissions, which would be a big problem in any ‘conventional’ (eg scramjet) hypersonic engine.
    - blinding-streak 2y ago
      ICPM! That's a new acronym you just coined!
    - pfdietz 2y ago
      > Fair, I hadn't considered the intercontinental ballistic passenger missile approach. The terminal deceleration on an ICBM trajectory would be lethal. Ballistic passenger transport at global distances has to be almost orbital so the entry is sufficiently shallow.
  - mppm 2y ago
    Once you get out of the atmosphere, lift is ~0 too.
    - Ajedi32 2y ago
      If you're going fast enough, you don't need lift. But judging by "in four hours" I'm guessing he's imagining something somewhere in between those two extremes. High enough to substantially reduce drag, low enough that you don't need to approach orbital velocity to maintain altitude.
      - mppm 2y ago
        "Fast enough" is very nearly orbital speed, though. Suborbital range is very short on the lower end, and increases rapidly and nonlinearly later. E.g. if you can boost to 2km/s (~ Mach 7), this gives you, I kid you not, around 200km of ballistic range. It's either atmospheric flight or orbital flight, and there's nothing really useful in between.
        adastra22 2y ago
        GP is not talking about a ballistic trajectory though.
        pfdietz 2y ago
        One possibility is a trajectory that's a series of skips.
    - jjk166 2y ago
      There actually is still significant lift. We define the edge of the atmosphere to be where the lift to drag ratio of a plane would be less than 1 below orbital velocity (ie if you were going fast enough to lift your weight with conventional wings you'd be in orbit), so you can't fly conventionally in space but lift might still be generating a force which is significant compared to your craft's weight.
      - echoangle 2y ago
- credit_guy 2y ago
  The air density decreases exponentially with the altitude, while the drag only increases quadratically with speed. It is entirely possible that there is an altitude, maybe 70km, where it is much more economical to fly (at supersonic speeds) than the current subsonic planes. Most likely the CEO of Boom ran the numbers, and the $100 ticket price is doable, at least if you exclude things like profit, capital depreciation, insurance, etc.
  - wnolens 2y ago
    > Most likely the CEO of Boom ran the numbers, and the $100 ticket price is doable Most likely it's aspirational, something to market to investors and potential employees.
    - credit_guy 2y ago
      > something to market to investors and potential employees Neither the investors nor the potential employees strike me as gullible. By the way, the $100 ticket price target was not for the first aircraft, see [1]: > The four hour, $100 dream is Boom’s long-term aim, two or three generations of aircraft down the line. [1] https://www.cnn.com/travel/article/boom-supersonic-four-hours-100-bucks/index.html https://www.cnn.com/travel/article/boom-supersonic-four-hour...
      - wnolens 2y ago
        Yes, and self driving cars are right around the corner!
        credit_guy 2y ago
        I don't get the analogy. The Boom CEO explicitly stated that $100 tickets are not around the corner. Two or three generations down the line means four decades at a minimum, if we think one generation takes 20 years. Lots of things can happen in 4 decades, like: significant advances in ramjet engines, rotation detonation engines become mainstream, people get comfortable with windowless aircraft (so there's no need for drooping nose Concorde-style), airports could start being equipped with arresting wires, like aircraft carriers today, airplanes without the vertical tail fin become common place, stronger and lighter composites become available, and, who knows, maybe even some jets will start running on hydrogen rather than jet fuel (hydrogen having about 3 times more energy density per unit of mass). I have to admit the even with all these things, $100 per ticket to any place in the world still seems like a stretch, but I'm willing to give the guy the benefit of the doubt.
- scythe 2y ago
  >Naively, traveling twice the speed requires 8x the power, so going over 4x the usual 550mph should mean over 64x more fuel burn You've forgotten to cancel the denominator. If you use the drag relation of speed to power, you're multiplying by time, but the time is reduced by the speed. It would be more straightforward to use the F ~ v^2 relation between speed and force. So going 4x as fast for the same distance would require 16x the fuel, while going 4x as fast for the same time would require 64x the fuel. But the latter would obviously never happen in practice as you'd circumnavigate the Earth.
  - hnuser123456 2y ago
    Oops, good catch, thank you. I got too sloppy with the napkin math.
jandrese 2y ago
New York to Sydney for $100 in 4 hours? My bullshit alarm is blaring. Unless they have a secret teleporter project they aren't telling people about. If you're burning dinosaurs to do that it is not happening, not unless oil becomes magically free and even then I think you would struggle to make ends meet.
- JumpCrisscross 2y ago
  > New York to Sydney for $100 in 4 hours? My bullshit alarm is blaring LA to Sydney is $10k on a good day for lie flat. You could probably charge $15 even 20k a seat and (a) turn a profit (b) filling the plane.
  - SahAssar 2y ago
    Did you miss the part you quoted that said "$100 in 4 hours"? It does not say $100k.
    - JumpCrisscross 2y ago
      > It does not say $100k >> You could probably charge $15 even 20k a seat Neither do I.
  - senordevnyc 2y ago
    That’s overstating it. I literally did this flight in Polaris yesterday (from NYC), and I’d say tickets from LA are more like $5-7k. There are lots of options from LA to Sydney next week in that range.

wraptile 2y ago

> which is anywhere in the world in four hours for 100 bucks That's while my tesla robotaxi is making that 100 bucks driving leprechauns to their golden pots! Totally not vaporware guys.

hnuser123456 2y ago

Huh. The longest flights are around 10,000 miles. They usually cost over $1000. Fuel apparently accounts for about 25% of ticket price on long haul, so $250 in fuel normally. To do that in 4 hours is to travel 2,500 mph. Naively, traveling twice the speed requires 8x the power, so going over 4x the usual 550mph should mean over 64x more fuel burn, or $16,000 in fuel alone. Maybe a bit less since drag doesn't grow quite as quickly above transonic, call it $10,000. But if a ticket's only $100, I guess they've figured out how to get gas for 0.25% of typical prices.

Ajedi32 2y ago
Once you get out of the atmosphere, drag (and fuel consumption) is ~0. So theoretically possible, but I'm not sure if that's what he was talking about. Certainly Overture won't be capable of that.
- hnuser123456 2y ago
  Fair, I hadn't considered the intercontinental ballistic passenger missile approach.
  - dylan604 2y ago
    Isn't that specifically one of the types of travel predicted to be made possible by reusable rockets capable of landing on the ground? From Florida to Japan in 45 minutes type of thing
    - adastra22 2y ago
      Yes point to point travel was a market for Starship. I think they’ve mostly backed off that though, as Starlink offers an easier market opportunity and just as much revenue potential. The supersonic plane would have advantages over the rocket approach though. Rockers require long, inconvenient transfers to offshore launch facilities. (But would have the selling point of a microgravity transit.)
    - notahacker 2y ago
      Reaction Engines in the UK spent over 35 years working mostly on that concept (though when they eventually went bust trying to scale up last year I think they were focused on reusable space launch business model which is ironically more realistic)
      - ballooney 2y ago
        No, they were working on the latter (skylon) most of the time, though the new management that came in after their £60M investment quickly dropped SSTO in favour of more immediate RoI applications. The passenger plane was LAPCAT which was a paper study commissioned by the EU. They did some interesting real work too, such as designing and testing a hypersonic engine combustion chamber that could reduce NOx emissions, which would be a big problem in any ‘conventional’ (eg scramjet) hypersonic engine.
  - blinding-streak 2y ago
    ICPM! That's a new acronym you just coined!
  - pfdietz 2y ago
    > Fair, I hadn't considered the intercontinental ballistic passenger missile approach. The terminal deceleration on an ICBM trajectory would be lethal. Ballistic passenger transport at global distances has to be almost orbital so the entry is sufficiently shallow.
- mppm 2y ago
  Once you get out of the atmosphere, lift is ~0 too.
  - Ajedi32 2y ago
    If you're going fast enough, you don't need lift. But judging by "in four hours" I'm guessing he's imagining something somewhere in between those two extremes. High enough to substantially reduce drag, low enough that you don't need to approach orbital velocity to maintain altitude.
    - mppm 2y ago
      "Fast enough" is very nearly orbital speed, though. Suborbital range is very short on the lower end, and increases rapidly and nonlinearly later. E.g. if you can boost to 2km/s (~ Mach 7), this gives you, I kid you not, around 200km of ballistic range. It's either atmospheric flight or orbital flight, and there's nothing really useful in between.
      - adastra22 2y ago
        GP is not talking about a ballistic trajectory though.
      - pfdietz 2y ago
        One possibility is a trajectory that's a series of skips.
  - jjk166 2y ago
    There actually is still significant lift. We define the edge of the atmosphere to be where the lift to drag ratio of a plane would be less than 1 below orbital velocity (ie if you were going fast enough to lift your weight with conventional wings you'd be in orbit), so you can't fly conventionally in space but lift might still be generating a force which is significant compared to your craft's weight.
    - echoangle 2y ago
credit_guy 2y ago
The air density decreases exponentially with the altitude, while the drag only increases quadratically with speed. It is entirely possible that there is an altitude, maybe 70km, where it is much more economical to fly (at supersonic speeds) than the current subsonic planes. Most likely the CEO of Boom ran the numbers, and the $100 ticket price is doable, at least if you exclude things like profit, capital depreciation, insurance, etc.
- wnolens 2y ago
  > Most likely the CEO of Boom ran the numbers, and the $100 ticket price is doable Most likely it's aspirational, something to market to investors and potential employees.
  - credit_guy 2y ago
    > something to market to investors and potential employees Neither the investors nor the potential employees strike me as gullible. By the way, the $100 ticket price target was not for the first aircraft, see [1]: > The four hour, $100 dream is Boom’s long-term aim, two or three generations of aircraft down the line. [1] https://www.cnn.com/travel/article/boom-supersonic-four-hours-100-bucks/index.html https://www.cnn.com/travel/article/boom-supersonic-four-hour...
    - wnolens 2y ago
      Yes, and self driving cars are right around the corner!
      - credit_guy 2y ago
        I don't get the analogy. The Boom CEO explicitly stated that $100 tickets are not around the corner. Two or three generations down the line means four decades at a minimum, if we think one generation takes 20 years. Lots of things can happen in 4 decades, like: significant advances in ramjet engines, rotation detonation engines become mainstream, people get comfortable with windowless aircraft (so there's no need for drooping nose Concorde-style), airports could start being equipped with arresting wires, like aircraft carriers today, airplanes without the vertical tail fin become common place, stronger and lighter composites become available, and, who knows, maybe even some jets will start running on hydrogen rather than jet fuel (hydrogen having about 3 times more energy density per unit of mass). I have to admit the even with all these things, $100 per ticket to any place in the world still seems like a stretch, but I'm willing to give the guy the benefit of the doubt.
scythe 2y ago
>Naively, traveling twice the speed requires 8x the power, so going over 4x the usual 550mph should mean over 64x more fuel burn You've forgotten to cancel the denominator. If you use the drag relation of speed to power, you're multiplying by time, but the time is reduced by the speed. It would be more straightforward to use the F ~ v^2 relation between speed and force. So going 4x as fast for the same distance would require 16x the fuel, while going 4x as fast for the same time would require 64x the fuel. But the latter would obviously never happen in practice as you'd circumnavigate the Earth.
- hnuser123456 2y ago
  Oops, good catch, thank you. I got too sloppy with the napkin math.

jandrese 2y ago

New York to Sydney for $100 in 4 hours? My bullshit alarm is blaring. Unless they have a secret teleporter project they aren't telling people about. If you're burning dinosaurs to do that it is not happening, not unless oil becomes magically free and even then I think you would struggle to make ends meet.

JumpCrisscross 2y ago
> New York to Sydney for $100 in 4 hours? My bullshit alarm is blaring LA to Sydney is $10k on a good day for lie flat. You could probably charge $15 even 20k a seat and (a) turn a profit (b) filling the plane.
- SahAssar 2y ago
  Did you miss the part you quoted that said "$100 in 4 hours"? It does not say $100k.
  - JumpCrisscross 2y ago
    > It does not say $100k >> You could probably charge $15 even 20k a seat Neither do I.
- senordevnyc 2y ago
  That’s overstating it. I literally did this flight in Polaris yesterday (from NYC), and I’d say tickets from LA are more like $5-7k. There are lots of options from LA to Sydney next week in that range.