Getting to space without violating the Proscriptions

Dilandu wrote:

SWM wrote:
That is indeed more than I remembered off the top of my head. But it does not completely invalidate the premise that if you can build a ship to reach orbital height, you probably can build a ship to reach orbital velocity.

Only in theory. The first rockets were send to orbital height in 1946, but it took almost 11 years and a lot of resources to send sattelite into space. And to achieve the orbit that isn't send you into the planet surface, you would need at least some guidance and active maneuvering capability AFTER launch.

Orbit is easy (that just needs enough thrust, for long enough in the right general direction), circular orbit is hard and a circular orbit in a predictable position is really hard (that needs telemetry and really complex controls). ICBMs don't have telemetry or external guidance and with 1950's guidance could still get within a couple of miles of their target. Now if you do what the Germans did, and launch 3,172 rockets (out of 6,048 built)hitting something out of pure dumb luck is a possibility - if nothing else you will clutter up low orbit with rocket casings enough to make them unheathly(look up Kessler Syndrome - a good reason to aim for highly elliptical orbits with very low perigee's).

AirTech wrote:and with 1950's guidance could still get within a couple of miles of their target.

Yes - but they generally relied upon the radio control, because the inertial systems before "Atlas"-E wasn't good enough.

Dilandu wrote:

AirTech wrote:and with 1950's guidance could still get within a couple of miles of their target.

Yes - but they generally relied upon the radio control, because the inertial systems before "Atlas"-E wasn't good enough.

No, ICBMs did not have radio control. They had internal inertial guidance systems, only.

SWM wrote:No, ICBMs did not have radio control. They had internal inertial guidance systems, only.

Sigh. Re-read manuals. Both the early "Atlas", and the "Titan-I", and the R-7 "Semyorka" have a radio-controlled guidance, because the inertial systems on the time of their design were considered too inaccurate even for megaton-range warheads. They need control centers with radars, that tracked the missile during the boost phase, and ordered corrections via datalink, if the tragectory wasn't as predicted. The "Atlas"-E modification was the first ICBM, that relied on the inertial guidance.