Like ski lifts climbing mountains, lift in stages, swap out lifters

[neil]

Hi Miladen: I just reviewed your 9 posts. The question is not if, but when will the first space elevator break? Deployment errors can break the ribbon. Adding strengthening threads can break the ribbon. Suppose we launch a 1/2 ton thread strengthening climber at the same hour daily. At a constant 200 kilometers per hour they will be spaced 4800 kilometers apart all the way to the counterweight. A slower climber will cause them to bunch up putting added strain on the ribbon, which may break at a weak point. Each climber should be able to identify weak spots as the ribbon will stretch more near a weak spot from the added weight of the climber. Stretch transients will produce similar signals, but a computer should be able to predict the movement of transients. Transients can be shrunk by changing the speed of a climber, briefly, at the right instant. In theory the next climber can repair each week spot in about one hour. If the climber can travel 210 kilometers per hour for the next twenty hours, the 4800 kilometer spacing can be re-established. Alternately the subsequent climbers can travel about 190 kilometers per hour and be launched at 25 hour intervals instead of 24 hour intervals. Slower is better if some of the repairs are doubtful or there are other problems such as lots of repaired spots. Allowing too little safety factor increases the probability of a break, The mass of the climbers can be increased slightly after each group of ten or so climbers, as at least the lower portion of the ribbon is now stronger, assuming optimum tension along the entire length of each strengthening thread, and no problems of other kinds. Optimum strengthening thread tension will be difficult, especially if climbers produce lots of stretch transients by changing speed frequently.
If the ribbon is at high risk for breaking, temporary relief is possible by reeling out some additional ribbon from the anchor ship. This reduces the tension near the anchor ship and the reduced tension takes more than a week to to travel as a transient to the counterweight. Now the counter weight is at a bit more than 91,000 kilometers, so it exerts more tension unless the mass of the counter weight is reduced. This can be done by sending retired climbers (stored at the counterweight) into solar orbit = littering. More tension is OK if the ribbon is stronger due to successful adding of strengthening strands, but is bad, if a weak spot goes unrepared until the tension transient reaches the weak spot. We can temporarily go back to launching half ton climbers, if the anchor ship has any more in inventory.   Neil

[Mladen Milinković]

Computers can be used more in monitoring condition of ribbon,and monitor weak spots even before real need for ribbon repair(if monitoring system enaf efficient its normal to presume that ribbon break will be rare or very rare),just dont know what type of sensor can be adequat for that purpose( very good idea that each climber scan ribbon,better then i was thinking),thanks on such detail review,as conclusion i dont see real elevator stoping problem(duo or multithreads  type).