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Microsoft Co-Founder Paul Allen Unveils Giant Plane for Private Space Launches

104 points by sasvari 15y ago

johno215 15y ago
Launching at a higher altitude allows the rocket engines to be optimized for low atmospheric pressure increasing their efficiency. In addition, the trajectory can be turned to a more horizontal angle earlier without having to fight drag too much. Another benefit of air launch is the ability to launch at a location and time of one's choosing. This is useful to avoid weather, avoid flying over land when launching in certain directions, and not having to share a range with other launchers.
- johno215 15y ago
  A negative is that it is a lot harder to check-out the vehicle when it is attached to an airplane than when it is on the ground. Also, on the ground the successful start-up of all the engines can be verified before the vehicle is released. If one engine fails to start, the rest can be shutdown with the vehicle still intact on the ground. But, when an air-launching, there is no going back once the vehicle is dropped.
  - sukuriant 15y ago
    Perhaps you can start the engines before dropping? If only a second or so before? Or is the force that instantaneous, that strong?
- FrojoS 15y ago
  Interesting, can you recommend further reading for the rocket engine optimization? It seems though, that in this case, SpaceX's Merlin Engine will be used.
  - johno215 15y ago
    http://en.wikipedia.org/wiki/Rocket_engine_nozzle#Atmospheric_use http://en.wikipedia.org/wiki/Rocket_engine_nozzle#Atmospheri...
darklajid 15y ago
I suck at physics and the article is light on details. Help me out. What is the gain here? You're still launching a rocket, but now at 30000m/9000ft? A rocket that is supposed to be similar to what exists today? I mean - smart people have this idea, so the benefit must be huge. Can someone explain in slow speech (How'd you explain the novelty of this to your kid) the incentive to me?
- bulte-rs 15y ago
  Considering that 30 kilometers is almost 100,000 feet you have a lot air you do NOT have to cross. This takes less (solid) fuel and is thus cheaper.
  - darklajid 15y ago
    I already stated my ignorance, so - I'll believe whatever claims are made here. But - my mind desperately tries to fight that and tells me about a _huuuge_ machine that needs to be maintained, and consumes fuel as well. And getting to 30km straight up in a rocket shape instead of going up in a loooong slope powered by someone else seems expensive, in terms of energy used.
    - marvin 15y ago
      It's not about energy, it's about momentum and energy/weight ratio. Due to the energy density of chemical fuels, the vast majority of a space rocket's fuel is actually used to carry the _rest_ of the rocket's fuel to the altitude at which it will be burned. I'm not good with rocket physics, but I'm pretty sure that gaining a few kilometers of altitude and 1000 km/h of kinetic energy will have a large impact on the total amount of fuel/propellant required to reach orbit. Is someone in here good enough with rocket physics to comment on this? Of course, it would be even better if they could go to business-jet altitudes or above (15000 meters instead of the 9000 quoted in the article), and I am guessing from the number and size of the engines that this is what they are actually aiming at. But this is just idle speculation on my part.
    - bulte-rs 15y ago
leoedin 15y ago
The companies involved are like a supergroup of cutting edge aerospace. Scaled and SpaceX collaborating! It's a nice concept, and it obviously works on a smaller scale for the pegasus guys as well as Virgin Galactic (although they're not putting anything into orbit). Hopefully this is successful!
michaelfeathers 15y ago
I thought Burt Rutan was working with Virgin Galactic on their venture.
- jmcqk6 15y ago
  He is/was. However, Paul Allen was a partner when Rutan was going after (and won) the X-prize. So really, they're just getting back together to work on something new.
- HeyLaughingBoy 15y ago
  I thought he retired a few months ago.
davidhansen 15y ago
Could someone help me understand the space thing? Specifically the phenomenon of rich engineers and businessmen like Allen, Carmack, Branson, Bezos, Shuttleworth, etc spending huge amounts of money on space-travel-related projects. I, like many nerds, grew up with a powerful fascination with space, cosmology, and the myriad science fiction novels based around the various problems and possibilities of space travel. I understand the allure. I am also a capitalist, and therefore don't begrudge these guys the opportunity to do with their money as they see fit. What I don't get is why we never hear of wealthy engineers spending their money on technology projects that would have a much much larger benefit to humanity, and arguably cooler than spaceflight. Things like nanotech, robotics, and hell, even cold fusion come to mind. Why space?
- mkr-hn 15y ago
  Because someone has to. Otherwise we're bound to this little rock forever. And bored billionaires are the only people with the money and will to do it right now. It's also the only way we'll develop better ways to get commercial payloads into orbit given the recent global obsession with austerity. edited to add: Storing a library in your pocket seemed impossible (or at least commercially unviable) a hundred years ago. No one would have given it a thought. It was just too far out there. How could you pack that much paper into a pocket? I know the limitations on space travel are grounded in sound science and will probably never be overcome. But I don't like the idea of accepting that we'll never find a way around it. "Because it's there" is good enough for now.
  - onemoreact 15y ago
    Just as fitting that much paper was an issue so is trying to fit that much propellant into an improved rocket. The number one limitation on real spaceflight (AKA past the moon) is power. Building an actual fusion reactor on earth would be worth more in therms of actually sending people to the ort cloud than all the private 'space flight' (aka yacht clubs) out there. PS: I am mostly taking issue with sub orbital flights / amusement parks. If you want to feel weightless for a few minutes a trip on something like the comet comet is affordable for most people and few people bother.
highace 15y ago
I wish we invested more into space exploration. Like, serious resources from every country in the world. To think that we squabble over silly things on this planet every day when there's a whole universe of stuff we can't even comprehend out there. Things always seem so trivial when you imagine the bigger picture, yet we worry about them anyway and I don't know why. There's a saying that struck a note with me... "We've been born too late to explore the earth, but too early to explore the universe".
DilipJ 15y ago
A 385 feet wingspan! amazing. It's about time someone beat the Spruce Goose.
- tomkarlo 15y ago
  The Spruce Goose was my first thought when I saw this (and not in a good way.) http://en.wikipedia.org/wiki/Hughes_H-4_Hercules http://en.wikipedia.org/wiki/Hughes_H-4_Hercules
martinkallstrom 15y ago
Space bums... littering used fuel cans everywhere ("any orbit, any time"). How sustainable is it to keep leaving half of every vehicle somewhere on the way to your destination? UPDATE: At first I was bemused that this was my reaction to their concept video. But then I realized that all the other concepts we have seen like SpaceX and Bezo's project actually don't litter. Isn't that correct? Other modern commercial space programs build for returning the entire vehicle home for reuse?
- kijin 15y ago
  Not exactly what you're looking for, but the Space Shuttle didn't leave any debris in orbit. The external tank was the only part that got dumped in the ocean, and it would shatter on impact because it's just a thin shell of aluminum. Solid boosters were much more robust, so they were salvaged and reused.
snorkel 15y ago
So ... what's the re-entry plan? Splash down? Call a Russian taxi?
- InclinedPlane 15y ago
  Assuming that this ends up using a variant of the SpaceX dragon capsule the re-entry plan would be a powered descent onto a targeted landing site.
nradov 15y ago
I wonder why the fuselages are only joined by the wing and not at the tail? Won't that subject the wing boxes to a lot of twisting stress?
- tomkarlo 15y ago
  If it's a fly-by wire system, you may be able to avoid twisting stress by varying the angles of the elevators on each tail so that you add force to oppose that twist. Also, I don't think it's expected to undertake any really drastic maneuvers. You'd fly it in decent weather on a relatively short ascent, and use a very gently take-off and landing profile.

104 points by sasvari 15y ago

Launching at a higher altitude allows the rocket engines to be optimized for low atmospheric pressure increasing their efficiency. In addition, the trajectory can be turned to a more horizontal angle earlier without having to fight drag too much. Another benefit of air launch is the ability to launch at a location and time of one's choosing. This is useful to avoid weather, avoid flying over land when launching in certain directions, and not having to share a range with other launchers.

johno215 15y ago
A negative is that it is a lot harder to check-out the vehicle when it is attached to an airplane than when it is on the ground. Also, on the ground the successful start-up of all the engines can be verified before the vehicle is released. If one engine fails to start, the rest can be shutdown with the vehicle still intact on the ground. But, when an air-launching, there is no going back once the vehicle is dropped.
- sukuriant 15y ago
  Perhaps you can start the engines before dropping? If only a second or so before? Or is the force that instantaneous, that strong?
FrojoS 15y ago
Interesting, can you recommend further reading for the rocket engine optimization? It seems though, that in this case, SpaceX's Merlin Engine will be used.
- johno215 15y ago
  http://en.wikipedia.org/wiki/Rocket_engine_nozzle#Atmospheric_use http://en.wikipedia.org/wiki/Rocket_engine_nozzle#Atmospheri...

darklajid 15y ago

I suck at physics and the article is light on details. Help me out. What is the gain here? You're still launching a rocket, but now at 30000m/9000ft? A rocket that is supposed to be similar to what exists today? I mean - smart people have this idea, so the benefit must be huge. Can someone explain in slow speech (How'd you explain the novelty of this to your kid) the incentive to me?

bulte-rs 15y ago
Considering that 30 kilometers is almost 100,000 feet you have a lot air you do NOT have to cross. This takes less (solid) fuel and is thus cheaper.
- darklajid 15y ago
  I already stated my ignorance, so - I'll believe whatever claims are made here. But - my mind desperately tries to fight that and tells me about a _huuuge_ machine that needs to be maintained, and consumes fuel as well. And getting to 30km straight up in a rocket shape instead of going up in a loooong slope powered by someone else seems expensive, in terms of energy used.
  - marvin 15y ago
    It's not about energy, it's about momentum and energy/weight ratio. Due to the energy density of chemical fuels, the vast majority of a space rocket's fuel is actually used to carry the _rest_ of the rocket's fuel to the altitude at which it will be burned. I'm not good with rocket physics, but I'm pretty sure that gaining a few kilometers of altitude and 1000 km/h of kinetic energy will have a large impact on the total amount of fuel/propellant required to reach orbit. Is someone in here good enough with rocket physics to comment on this? Of course, it would be even better if they could go to business-jet altitudes or above (15000 meters instead of the 9000 quoted in the article), and I am guessing from the number and size of the engines that this is what they are actually aiming at. But this is just idle speculation on my part.
  - bulte-rs 15y ago

leoedin 15y ago

The companies involved are like a supergroup of cutting edge aerospace. Scaled and SpaceX collaborating! It's a nice concept, and it obviously works on a smaller scale for the pegasus guys as well as Virgin Galactic (although they're not putting anything into orbit). Hopefully this is successful!

michaelfeathers 15y ago

I thought Burt Rutan was working with Virgin Galactic on their venture.

jmcqk6 15y ago
He is/was. However, Paul Allen was a partner when Rutan was going after (and won) the X-prize. So really, they're just getting back together to work on something new.
HeyLaughingBoy 15y ago
I thought he retired a few months ago.

davidhansen 15y ago

Could someone help me understand the space thing? Specifically the phenomenon of rich engineers and businessmen like Allen, Carmack, Branson, Bezos, Shuttleworth, etc spending huge amounts of money on space-travel-related projects. I, like many nerds, grew up with a powerful fascination with space, cosmology, and the myriad science fiction novels based around the various problems and possibilities of space travel. I understand the allure. I am also a capitalist, and therefore don't begrudge these guys the opportunity to do with their money as they see fit. What I don't get is why we never hear of wealthy engineers spending their money on technology projects that would have a much much larger benefit to humanity, and arguably cooler than spaceflight. Things like nanotech, robotics, and hell, even cold fusion come to mind. Why space?

mkr-hn 15y ago
Because someone has to. Otherwise we're bound to this little rock forever. And bored billionaires are the only people with the money and will to do it right now. It's also the only way we'll develop better ways to get commercial payloads into orbit given the recent global obsession with austerity. edited to add: Storing a library in your pocket seemed impossible (or at least commercially unviable) a hundred years ago. No one would have given it a thought. It was just too far out there. How could you pack that much paper into a pocket? I know the limitations on space travel are grounded in sound science and will probably never be overcome. But I don't like the idea of accepting that we'll never find a way around it. "Because it's there" is good enough for now.
- onemoreact 15y ago
  Just as fitting that much paper was an issue so is trying to fit that much propellant into an improved rocket. The number one limitation on real spaceflight (AKA past the moon) is power. Building an actual fusion reactor on earth would be worth more in therms of actually sending people to the ort cloud than all the private 'space flight' (aka yacht clubs) out there. PS: I am mostly taking issue with sub orbital flights / amusement parks. If you want to feel weightless for a few minutes a trip on something like the comet comet is affordable for most people and few people bother.

highace 15y ago

I wish we invested more into space exploration. Like, serious resources from every country in the world. To think that we squabble over silly things on this planet every day when there's a whole universe of stuff we can't even comprehend out there. Things always seem so trivial when you imagine the bigger picture, yet we worry about them anyway and I don't know why. There's a saying that struck a note with me... "We've been born too late to explore the earth, but too early to explore the universe".

DilipJ 15y ago

A 385 feet wingspan! amazing. It's about time someone beat the Spruce Goose.

tomkarlo 15y ago
The Spruce Goose was my first thought when I saw this (and not in a good way.) http://en.wikipedia.org/wiki/Hughes_H-4_Hercules http://en.wikipedia.org/wiki/Hughes_H-4_Hercules

martinkallstrom 15y ago

Space bums... littering used fuel cans everywhere ("any orbit, any time"). How sustainable is it to keep leaving half of every vehicle somewhere on the way to your destination? UPDATE: At first I was bemused that this was my reaction to their concept video. But then I realized that all the other concepts we have seen like SpaceX and Bezo's project actually don't litter. Isn't that correct? Other modern commercial space programs build for returning the entire vehicle home for reuse?

kijin 15y ago
Not exactly what you're looking for, but the Space Shuttle didn't leave any debris in orbit. The external tank was the only part that got dumped in the ocean, and it would shatter on impact because it's just a thin shell of aluminum. Solid boosters were much more robust, so they were salvaged and reused.

snorkel 15y ago

So ... what's the re-entry plan? Splash down? Call a Russian taxi?

InclinedPlane 15y ago
Assuming that this ends up using a variant of the SpaceX dragon capsule the re-entry plan would be a powered descent onto a targeted landing site.

nradov 15y ago

I wonder why the fuselages are only joined by the wing and not at the tail? Won't that subject the wing boxes to a lot of twisting stress?

tomkarlo 15y ago
If it's a fly-by wire system, you may be able to avoid twisting stress by varying the angles of the elevators on each tail so that you add force to oppose that twist. Also, I don't think it's expected to undertake any really drastic maneuvers. You'd fly it in decent weather on a relatively short ascent, and use a very gently take-off and landing profile.