Building a Stratospheric Balloon Launch Company with Zero 2 Infinity
1–10 of 14 posts
Re: Building a Stratospheric Balloon Launch Company with Zero 2 Infinity
#2pixar's up of space companies. launches would be a lot more quiet.
Re: Building a Stratospheric Balloon Launch Company with Zero 2 Infinity
#3That space vehicle they show in their mockups, the conical capsule with 6 engines, can't possibly have enough delta-v for an orbital injection. For one, not enough fuel to run all those engines for a long enough time.
Any orbital launch must end up with the payload going 4.5 km/s at LEO (about 200 km altitude). For a classic rocket launcher, this happens after about 450 seconds. See for example the Falcon 9 velocity and altitude traces from [1]
This baloon launcher skips the altitude gain of the first 120s of a Falcon 9 launch. Not bad, but it can't skip the velocity gain - it still needs to inject 4.5 kmps delta-v.
The Paul Allen financed Stratolauncher project starts from a similar high altitude-low velocity point, but was planned to use quite a beefy rocket launched from a carrier plane to inject delta-v to the payload.
Maybe that capsule is just a suborbital vehicle. They're quite popular as a stepping stone.
[1] https://forum.nasaspaceflight.com/index.php?topic=40983.0
Re: Building a Stratospheric Balloon Launch Company with Zero 2 Infinity
#4That space vehicle they show in their mockups, the conical capsule with 6 engines, can't possibly have enough delta-v for an orbital injection. For one, not enough fuel to run all those engines for a long enough time. Any orbital launch must end up with the payload going 4.5 km/s at LEO (about 200 km altitude). For a classic rocket launcher, this happens after about 450 seconds. See for example the Falcon 9 velocity…
I agree with your analysis, from the initial rocket concepts the delta-v does look lacking. One note however, I think you may be confusing your kilometers with miles - one needs around 7.8km/s for a stable LEO.
Re: Building a Stratospheric Balloon Launch Company with Zero 2 Infinity
#5Very reminiscent of http://www.jpaerospace.com/
Re: Building a Stratospheric Balloon Launch Company with Zero 2 Infinity
#6That space vehicle they show in their mockups, the conical capsule with 6 engines, can't possibly have enough delta-v for an orbital injection. For one, not enough fuel to run all those engines for a long enough time. Any orbital launch must end up with the payload going 4.5 km/s at LEO (about 200 km altitude). For a classic rocket launcher, this happens after about 450 seconds. See for example the Falcon 9 velocity…
Ballon launches are unlikely to be economically viable.
But, what I find amusing is simply by going up you gain a little velocity from earth’s rotation via atmospheric drag. It’s kind of the opposite of everywhere else in aerospace engineering.
Re: Building a Stratospheric Balloon Launch Company with Zero 2 Infinity
#7That space vehicle they show in their mockups, the conical capsule with 6 engines, can't possibly have enough delta-v for an orbital injection. For one, not enough fuel to run all those engines for a long enough time. Any orbital launch must end up with the payload going 4.5 km/s at LEO (about 200 km altitude). For a classic rocket launcher, this happens after about 450 seconds. See for example the Falcon 9 velocity…
I don't work for Z2I (I run Space Bandits) but that's a good point and definitely would have been worth including in the interview.
I found this explanation in their payload user guide of an example flight profile (excerpt):
The first stage burns for 110 seconds, upon which the vehicle reaches an altitude of 80 km and an inertial speed of 2.3 km/s. After ejecting the first stage, the vehicle reaches 400 km and 4.4 km/s in 230 seconds. Upon third and final stage separation, the third stage performs multiple firings, the first one lasting 340 seconds and reaching 600 km of altitude while still slightly below the target orbital speed. Then, after coasting and later finalizing the orbit, the payload is released.
See page 23: http://www.zero2infinity.space/wp-content/uploads/2018/01/Z2...
Thanks for raising that :)
Re: Building a Stratospheric Balloon Launch Company with Zero 2 Infinity
#8That space vehicle they show in their mockups, the conical capsule with 6 engines, can't possibly have enough delta-v for an orbital injection. For one, not enough fuel to run all those engines for a long enough time. Any orbital launch must end up with the payload going 4.5 km/s at LEO (about 200 km altitude). For a classic rocket launcher, this happens after about 450 seconds. See for example the Falcon 9 velocity…
Ballon launches are unlikely to be economically viable. But, what I find amusing is simply by going up you gain a little velocity from earth’s rotation via atmospheric drag. It’s kind of the opposite of everywhere else in aerospace engineering.
Out of curiosity, what do you think will make then not viable economically? There's a lot of advantages they have compared to rockets, particularly for smallsats.
Re: Building a Stratospheric Balloon Launch Company with Zero 2 Infinity
#9That space vehicle they show in their mockups, the conical capsule with 6 engines, can't possibly have enough delta-v for an orbital injection. For one, not enough fuel to run all those engines for a long enough time. Any orbital launch must end up with the payload going 4.5 km/s at LEO (about 200 km altitude). For a classic rocket launcher, this happens after about 450 seconds. See for example the Falcon 9 velocity…
I agree with your analysis, from the initial rocket concepts the delta-v does look lacking. One note however, I think you may be confusing your kilometers with miles - one needs around 7.8km/s for a stable LEO.
Not the OP you're replying to but you're right! I'll try to get more information on this and update once I do. Thanks!
Re: Building a Stratospheric Balloon Launch Company with Zero 2 Infinity
#10Very reminiscent of http://www.jpaerospace.com/
Really cool that they were essentially a bunch of volunteers working together to try something innovative like this - and that was before SpaceX was founded! It's a shame their rockoon prototype didn't succeed, though.