Bolo = short rotovator

My guess is we are close to deploying a short bolo, without a first stage to reach the tip at perhaps 5 kilometers per second, altitude 200 kilometers, briefly at 22 second intervals. The center is orbiting at 8 and the outer tip at 11 kilometers per second, so it can put perhaps one ton in LEO at 240 kilometers in a circular orbit. So the bolo is 20 kilometers radius, with the tips chasing each other at 3 kilometers per second Circumference of the tip path is 125.6 kilometers. We gain 6 kilometers per second with respect to Earth's surface at the poles, if I'm not confused. The pay load will experience several g. A longer bolo can put payloads in orbit at higher altitudes and faster speeds and/or lower g loading of the payload. If the tether survives a month, it is likely reparable long term with an Edwards type climber, so we will fund the climber and a vehicle to attach a payload at 200 kilometers at 5 kilometers per second. If it survives less than a month, we will attempt a better tether design and evasive maneuvers to dodge space junk. The Edwards type climber can help dodge the space junk by starting and stopping and reversing direction. This puts traveling transients on the tether which change the tether position (hopefully) by enough to miss the piece of space junk. The momentum exchange is not free. The bolo will loose altitude and rotational speed with each attachment and each launch, unless there is a means to restore the altitude and tip speed. I suggest a tip rocket at each of the two tips. That means some of the attachments need to be fuel for the tip rockets. In theory we can do almost 300 attachments and releases per hour, and serve all the countries of Earth, with a semi polar orbit, so enormous amounts of mass can be orbited even at one ton per launch. There is also a rather nasty jerk shortly after the attachment of each payload. The tether will stretch significantly, perhaps a lot. The tip rocket can likely reduce the jerk and give the pay load a slight extra boost and direction change at release, if this is desirable for this launch. Neil Archived source: https://web.archive.org/web/20101205115135/http://www.spacetimeandtheuniverse.com/general-physics/3918-bolo-short-rotovator.html