D-Shift
Would it not be possible to use a giant linear electromagnetic motor, powerd buy mega-ultra-extremo capacitors to accelerate the vehicle into space? of course there are limits on how much G force a person can exprience, but surely in combination with a smaller booster rocket, a LEM launch would make the initial launch more efficient and the whole process a lot cheaper?
Slowburn
As the strength to weight ratio in structural materials improves all sorts of things once considered impossible have become reality. I remember being told that the Gossamer Albatross\'s flights were faked because human powered airplanes were impossible.
windykites
This is an excellent video, but what strikes me, is the amount of extra fuel/weight which is required to return the boosters back to Earth. what happened to parachutes with sea recovery? Also the payload capsule requires retro rockets. I am surprised that this system is feasible.
Stewart Mitchell
Forget the sea recovery , just parachute onto a giant air bag. Do not miss the target.
Tellurider
UP Aerospace has had numerous sub-orbital launches at Spaceport America and recovered the rocket at nearby White Sands Missile Range. Jerry Larsan has proved it all works just fine. Check out the website for the next launch (www.spaceportamerica.com) and (www.up-aerospace.biz).
VirtualGathis
If you read the original articles spaceX speaks of why parachutes to sea recovery are not working. First the vehicles are breaking up before they are low enough for chutes. Second the chutes, deployment system and sea hardening/airbags are adding more weight than the recovery fuel weight would be according their math.
YetAnotherBob
@D-Shift, No, the air resistance would be fantastic. For the near orbital velocity you would need, the muzzle velocity is around 17 Kilometers per second. But, that still requires a burn at apogee to prevent you from just coming back down very fast for a very hard landing. This has all been studied out very carefully. The sonic boom at the launch end would be fatal of you were closer than a couple of Kilometers from the muzzle.
There was one proposal for it. If the launch mechanism were built in a tube that was evacuated (Pumped down to a vacuum) then you could accelerate up to speed, if then the cap were removed very fast (a modest few hundred Kilo\'s of C4 should do it), then you could be launched into an extreme orbit. But any such orbit from ground level would then later intersect the ground again. That is why there is a need to have a \'burn\' in orbit.
If you increase the mass of the payload to allow for a much larger delta V (Change in velocity), then you can reduce the speed requirement of the catapult. This allows you to fire at a steeper angle, but there is still the little requirement for horizontal acceleration to around 17,000 KM per Hour. In all, it\'s not a simple solution.
If on the other hand you are on the moon, it\'s much simpler. There are much easier designs for such catapults to be built on the Moon. No air, and a lessening of the required velocity changes by around 36 times. In fact, if you stage it right, you could launch directly from the Lunar surface to either the L1 or L2 points, or directly to the Earth. The atmosphere makes it extremely hard to do the same from the surface of the earth.
I hope this helps you understand.
Christian Lassen
Cool to see this. My brother and two other guys built the casing for the test version of their stage two rocket. The tests were pretty cool to watch. They\'re somewhere online.
D-Shift
@YetAnotherBob- Thank you for you explanation, It was very insightful. I was unaware of the extreme horizontal velocities needed for orbit.
dugnology
This would be nice if it works, but what is the weight & complexity penalty v.s. the cost of throwaway. Since it is designed to be man-rated, I imagine that the vehicle is designed with considerable margins. The stages will be un-manned on the way back the parts involved in landing (which are beefy enough for takeoff weight) could be held to a lower standard. I imagine that the stages would be somewhat self stabilizing (all the weight is on the bottom) and very light. The descent profile could get it out of the need for a heavy heat shield. I wish him luck. We need more people like Elon.