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That is sad. I thought the idea of using a 747 as a glorified first stage (or stage 0) was sound as it saved a ton of money. I wonder why they couldn't make i

That is sad. I thought the idea of using a 747 as a glorified first stage (or stage 0) was sound as it saved a ton of money. I wonder why they couldn't make it work. And why does a single failure doom a company after 4 successful launches.

PlutoIsAPlanet 4y ago
Elon said somewhere that using a carrier aircraft to replace the first stage doesn’t scale. I think Virgins space ventures are all pretty much dead in the water, similar the space plane it’s just outdated and outmatched by the competition.
- deleted 4y ago
  [deleted]
stametseater 4y ago
Orbital Sciences, now Northrop Grumman, has successfully used plane launches for the Pegasus a few dozen times since the 90s. They use a Lockheed TriStar instead of a 747, but the principle is the same. It definitely works. Their launch volume has been trending down though. I don't think they're able to effectively compete for most contracts.
- ianburrell 4y ago
  There are other small-sat rocket which are cheaper. The Rocket Lab Electron is $7.5 million for 250kg while Pegasus is $40 million for 450kg. Plus, SpaceX has piggyback program for small sats that is cheaper but longer wait.
- jojosbuddy 4y ago
  Yes, launch stage was pretty bulletproof, 2nd upto the liquid stage were the problems (should be fixed by now that the tech exists). The systems are likely the same as 2005 that new VC funded launch companies can undercut price with updated designs/tech (R&D expenses absorbed by VCs). I think the telemetry live stream/OpenGl viz of the last minotaur launch looked like a slightly revised UIX of the original live stream tool I built back in the 90s (I worked on Pegasus), aka old tech, not shiny. Edit: Really it's a potential energy to cost problem. 5% more efficiency is [actually] big when leaving this planet, but yes, cost of air launch is still stuck in 1990 times. From the outside I didn't see any innovation from the VO team aside from electronics. As for VG, I used to work with their new CEO and Eng VP: they know ops, but I thought the systems/tech hadn't been flush out 100%, so may have the similar fate if a few customers start canceling. I have some ideas to 'fix' air launch requiring big R&D, but knee deep in fixing autonomous drones! Peg was not financially successful cause prior 2002, the space race was maybe 15 launches a year: not profitable. Stuff like Iridium failed, shutting down ideas of having thousands of sats in LEO, mind that the only markets were communications (cellular/fiber won), science experiments, and imaging (imaging/remote sensing? Drone tech will eventually win). Luckily LEO payloads are a cool idea again-- tech is better + moore's law, thus demand is HOT. Heck Orbcomm is up there today, but old tech no one really wants. Today, Elon played the long game (2002) and kept innovating where SpaceX has found the cost-benefit balance via reusability, and [with timing] being the only system post Shuttle it's a duopoly with ULA--charge as much to stay in the black. BUT the markets are still the 3 above, nothing new (Elon's Mars thing == passion project) though every country now wants their 'own constellation' cause of the NRO, hehe. Trivia Edit: Peg's GNC computer was an 80386SX :)
  - panick21_ 4y ago
    That rocket close to as much as a Falcon 9 now cost.
- SonicScrub 4y ago
  It definitely works. But whether the it works economically compared with the traditional static ground launch is the question. Pegasus is simply more expensive than it's ground based competition.
- trollerator23 4y ago
  Even Antonio Elias, the person behind Pegasus and main designer, admitted that it didn't work out at all the way they predicted. You had the complication and rigmarole of launching from an aircraft but you still had to launch close to a range for comm and safety reasons.
ptmcc 4y ago
It seems like a neat idea but it really doesn't save money, though. The hard part, as in the vast majority of energy & fuel needed, is to get horizontal velocity not altitude. The complexity and cost of a 747 carrying a rocket up for an additional maybe ~3% of orbital velocity just doesn't pencil out in the end And reusable boosters sway the calculus even further toward ground-based launches, both in cost and launch system simplification.
- simonh 4y ago
  Indeed. As usual XKCD is helpful here. https://what-if.xkcd.com/58/ https://what-if.xkcd.com/58/ It's similar to why launching from a mountain top isn't worth it. If you're launching to a few hundred km altitude, a 2km or even a 10km head start is peanuts. And altitude is only a small fraction of the problem, compared to orbital speeds large jet aircraft are barely even moving. If you're launching anti-satelite missiles that's different. Getting altitude is the main aim, and military jets can get reasonably high with a small missile as payload.
  - hoseja 4y ago
    The major savings is in exponentially less air to go through, so you can do more aggressive gravity turn so you have less gravity losses. And he didn't even address the reentry questions, both of which are actually plausible - if you somehow have the fuel to drastically reduce your orbital velocity, you're suddenly no different than a sounding rocket, indeed not needing a heat shield. And if you cleverly slow down your reentry over many orbits, it can be very gentle.
    - SonicScrub 4y ago
      The benefits of the "exponentially less air" diminish once you have to slap an aerosurface on the vehicle (added weight + drag) to perform the pitch up maneuver Coupled with the fact that on deployment the vehicle is gaining velocity in the wrong direction until the engines ignite, accelerate forwards, and the vehicle begins the turn. The theoretical benefits of air launch quickly fade away given these practical realities. Nevermind the much more complex operations that comes with air launch. There's a reason why air launch has more or less died as an idea. The theoretical savings don't typically manifest once the additional complexities are accounted for.
wongarsu 4y ago
> And why does a single failure doom a company "This one failure killed it" is a poplar story. See also Zeppelins being doomed by the Hindenburg disaster, and the Concorde being doomed by an exploding tire. Failures can be the straw that breaks the camel's back, but saying they are the reason for killing their product is only true in the technical sense.
- bombcar 4y ago
  Yeah, usually a "single failure" dooms something that was already on life support.
generj 4y ago
To pile on on other comments regarding the non viability of air launch rocketry, the only reason it makes sense is for rerouting launch locations based on weather. The only customer needing an asset in orbit regardless of a weather violation is the military. The other bonus would be spreading out launch locations to essentially any airport rather than a few launch locations that could be denied by enemies. However their desire for it hasn’t been enough to fund it. Even Astra (with a similar launch anywhere, whenever premise) hasn’t been robustly funded by the US military.
panick21_ 4y ago
Its literally the exact opposite of saving money. It cost a HUGE amount of money. The reason is that in the plane you have people, so the rocket design has to take that into account and validating the rocket costs more. Just for reference, SpaceX and RocketLab sent their rocket to space for under 100M, while Virgin spend like 500M. That's partly because of worse leadership, but its partly inherent. A plane also isn't cheap, a ground launch station for a small rocket isn't that expensive. Additionally engineering the rocket to get carried vertically adds structure, that cost money and lowers payload. You end up not gaining that much from air-launch. It also makes the structure and avionics quite complex. Once you drop the rocket, the engine has to start or the payload is gone. Other rockets can start the engine, verify its good and then launch. Relativity space just did that. It also puts huge constraints on your rockets, the size in both weight and volume is inherently limited, and you can't evolve the architecture. In comparison SpaceX Falcon 1 could have easily been slightly upgraded and turned into a rocket that could lift 1T+ and even more eventually. And then they managed to use that engine to build a Falcon 9. Virgin Orbit has this one rocket, and its impossible to make back 100s of millions of investment with a tiny rocket and low launch cadence. They can't make the rocket significantly bigger because of the limits of the plane. I thought it was impossible for them to ever be a real company and that seem to have ended up happening. Launch is a really tough business. > And why does a single failure doom a company after 4 successful launches. Because they have already burned down a gigantic amount of cash and were in a bad stage, launch success or not. A launch earns them 12M or so. That basically nothing considering their investments and their burn.
- starik36 4y ago
  > Virgin spend like 500M Is that really true? If it is, I am struggling to understand what the money is being spent on. I mean the cost of Space Shuttle launches was in that neighborhood.
  - panick21_ 4y ago
    We don't have official numbers but pretty good industry reporting that puts the numbers there. Read Eric Bergers reporting on them over the last 5 years or so. Its mostly just lots of people and time. Plus buying 1-2 planes. Space Shuttle development was of course way more. A single margin launch cost 500M. But with fixed cost it was 1 billion+.
TechBro8615 4y ago
I'm surprised they would ever shut it down. I always thought of these corporate space programs as pet projects of billionaires with effectively infinite funding.
credit_guy 4y ago
If you work out the rocket equation, it turns out that you can achieve the delta-v of this stage 0 with about a 30% increase in fuel (assuming a 3 km/s exhaust velocity). Since the volume of a tank goes up with the cube of the linear dimensions, you need to increase the height and diameter of the boosters by only 10%. This seems to me to be a much easier task than engineering the whole mechanism of keeping a rocket hooked on a moving airplane, dealing with vibrations, make it sturdy enough so it does not collapse when it's not in a vertical position, and lots of other challenges associated with the unusual launch mode.

PlutoIsAPlanet 4y ago

Elon said somewhere that using a carrier aircraft to replace the first stage doesn’t scale. I think Virgins space ventures are all pretty much dead in the water, similar the space plane it’s just outdated and outmatched by the competition.

deleted 4y ago
[deleted]

stametseater 4y ago

Orbital Sciences, now Northrop Grumman, has successfully used plane launches for the Pegasus a few dozen times since the 90s. They use a Lockheed TriStar instead of a 747, but the principle is the same. It definitely works. Their launch volume has been trending down though. I don't think they're able to effectively compete for most contracts.

ianburrell 4y ago
There are other small-sat rocket which are cheaper. The Rocket Lab Electron is $7.5 million for 250kg while Pegasus is $40 million for 450kg. Plus, SpaceX has piggyback program for small sats that is cheaper but longer wait.
jojosbuddy 4y ago
Yes, launch stage was pretty bulletproof, 2nd upto the liquid stage were the problems (should be fixed by now that the tech exists). The systems are likely the same as 2005 that new VC funded launch companies can undercut price with updated designs/tech (R&D expenses absorbed by VCs). I think the telemetry live stream/OpenGl viz of the last minotaur launch looked like a slightly revised UIX of the original live stream tool I built back in the 90s (I worked on Pegasus), aka old tech, not shiny. Edit: Really it's a potential energy to cost problem. 5% more efficiency is [actually] big when leaving this planet, but yes, cost of air launch is still stuck in 1990 times. From the outside I didn't see any innovation from the VO team aside from electronics. As for VG, I used to work with their new CEO and Eng VP: they know ops, but I thought the systems/tech hadn't been flush out 100%, so may have the similar fate if a few customers start canceling. I have some ideas to 'fix' air launch requiring big R&D, but knee deep in fixing autonomous drones! Peg was not financially successful cause prior 2002, the space race was maybe 15 launches a year: not profitable. Stuff like Iridium failed, shutting down ideas of having thousands of sats in LEO, mind that the only markets were communications (cellular/fiber won), science experiments, and imaging (imaging/remote sensing? Drone tech will eventually win). Luckily LEO payloads are a cool idea again-- tech is better + moore's law, thus demand is HOT. Heck Orbcomm is up there today, but old tech no one really wants. Today, Elon played the long game (2002) and kept innovating where SpaceX has found the cost-benefit balance via reusability, and [with timing] being the only system post Shuttle it's a duopoly with ULA--charge as much to stay in the black. BUT the markets are still the 3 above, nothing new (Elon's Mars thing == passion project) though every country now wants their 'own constellation' cause of the NRO, hehe. Trivia Edit: Peg's GNC computer was an 80386SX :)
- panick21_ 4y ago
  That rocket close to as much as a Falcon 9 now cost.
SonicScrub 4y ago
It definitely works. But whether the it works economically compared with the traditional static ground launch is the question. Pegasus is simply more expensive than it's ground based competition.
trollerator23 4y ago
Even Antonio Elias, the person behind Pegasus and main designer, admitted that it didn't work out at all the way they predicted. You had the complication and rigmarole of launching from an aircraft but you still had to launch close to a range for comm and safety reasons.

ptmcc 4y ago

It seems like a neat idea but it really doesn't save money, though. The hard part, as in the vast majority of energy & fuel needed, is to get horizontal velocity not altitude. The complexity and cost of a 747 carrying a rocket up for an additional maybe ~3% of orbital velocity just doesn't pencil out in the end And reusable boosters sway the calculus even further toward ground-based launches, both in cost and launch system simplification.

simonh 4y ago
Indeed. As usual XKCD is helpful here. https://what-if.xkcd.com/58/ https://what-if.xkcd.com/58/ It's similar to why launching from a mountain top isn't worth it. If you're launching to a few hundred km altitude, a 2km or even a 10km head start is peanuts. And altitude is only a small fraction of the problem, compared to orbital speeds large jet aircraft are barely even moving. If you're launching anti-satelite missiles that's different. Getting altitude is the main aim, and military jets can get reasonably high with a small missile as payload.
- hoseja 4y ago
  The major savings is in exponentially less air to go through, so you can do more aggressive gravity turn so you have less gravity losses. And he didn't even address the reentry questions, both of which are actually plausible - if you somehow have the fuel to drastically reduce your orbital velocity, you're suddenly no different than a sounding rocket, indeed not needing a heat shield. And if you cleverly slow down your reentry over many orbits, it can be very gentle.
  - SonicScrub 4y ago
    The benefits of the "exponentially less air" diminish once you have to slap an aerosurface on the vehicle (added weight + drag) to perform the pitch up maneuver Coupled with the fact that on deployment the vehicle is gaining velocity in the wrong direction until the engines ignite, accelerate forwards, and the vehicle begins the turn. The theoretical benefits of air launch quickly fade away given these practical realities. Nevermind the much more complex operations that comes with air launch. There's a reason why air launch has more or less died as an idea. The theoretical savings don't typically manifest once the additional complexities are accounted for.

wongarsu 4y ago

> And why does a single failure doom a company "This one failure killed it" is a poplar story. See also Zeppelins being doomed by the Hindenburg disaster, and the Concorde being doomed by an exploding tire. Failures can be the straw that breaks the camel's back, but saying they are the reason for killing their product is only true in the technical sense.

bombcar 4y ago
Yeah, usually a "single failure" dooms something that was already on life support.

generj 4y ago

To pile on on other comments regarding the non viability of air launch rocketry, the only reason it makes sense is for rerouting launch locations based on weather. The only customer needing an asset in orbit regardless of a weather violation is the military. The other bonus would be spreading out launch locations to essentially any airport rather than a few launch locations that could be denied by enemies. However their desire for it hasn’t been enough to fund it. Even Astra (with a similar launch anywhere, whenever premise) hasn’t been robustly funded by the US military.

panick21_ 4y ago

Its literally the exact opposite of saving money. It cost a HUGE amount of money. The reason is that in the plane you have people, so the rocket design has to take that into account and validating the rocket costs more. Just for reference, SpaceX and RocketLab sent their rocket to space for under 100M, while Virgin spend like 500M. That's partly because of worse leadership, but its partly inherent. A plane also isn't cheap, a ground launch station for a small rocket isn't that expensive. Additionally engineering the rocket to get carried vertically adds structure, that cost money and lowers payload. You end up not gaining that much from air-launch. It also makes the structure and avionics quite complex. Once you drop the rocket, the engine has to start or the payload is gone. Other rockets can start the engine, verify its good and then launch. Relativity space just did that. It also puts huge constraints on your rockets, the size in both weight and volume is inherently limited, and you can't evolve the architecture. In comparison SpaceX Falcon 1 could have easily been slightly upgraded and turned into a rocket that could lift 1T+ and even more eventually. And then they managed to use that engine to build a Falcon 9. Virgin Orbit has this one rocket, and its impossible to make back 100s of millions of investment with a tiny rocket and low launch cadence. They can't make the rocket significantly bigger because of the limits of the plane. I thought it was impossible for them to ever be a real company and that seem to have ended up happening. Launch is a really tough business. > And why does a single failure doom a company after 4 successful launches. Because they have already burned down a gigantic amount of cash and were in a bad stage, launch success or not. A launch earns them 12M or so. That basically nothing considering their investments and their burn.

starik36 4y ago
> Virgin spend like 500M Is that really true? If it is, I am struggling to understand what the money is being spent on. I mean the cost of Space Shuttle launches was in that neighborhood.
- panick21_ 4y ago
  We don't have official numbers but pretty good industry reporting that puts the numbers there. Read Eric Bergers reporting on them over the last 5 years or so. Its mostly just lots of people and time. Plus buying 1-2 planes. Space Shuttle development was of course way more. A single margin launch cost 500M. But with fixed cost it was 1 billion+.

TechBro8615 4y ago

I'm surprised they would ever shut it down. I always thought of these corporate space programs as pet projects of billionaires with effectively infinite funding.

credit_guy 4y ago

If you work out the rocket equation, it turns out that you can achieve the delta-v of this stage 0 with about a 30% increase in fuel (assuming a 3 km/s exhaust velocity). Since the volume of a tank goes up with the cube of the linear dimensions, you need to increase the height and diameter of the boosters by only 10%. This seems to me to be a much easier task than engineering the whole mechanism of keeping a rocket hooked on a moving airplane, dealing with vibrations, make it sturdy enough so it does not collapse when it's not in a vertical position, and lots of other challenges associated with the unusual launch mode.