Linear Cables

Stabilization and elevator cables on the launch loop are very long, and propagation delay is a big issue. In most systems people are familiar with, cables are short enough and forces change slowly enough that propagation delay is not a major issue. With a launch loop, forces can change rapidly (milliseconds) while the propagation delays are 10s of seconds.

For example, when an instantaneous force change is applied to one end of a very long cable, the end does not stretch a little, it moves, and keeps moving until the force has had time to propagate to the attachment and back. For a 100km stabilization cable, that can be 20 seconds, in which time many meters of cable moves.

Material	density	modulus	strength	CTE	Vsound	Length	Round Trip	100Km*100K
	gm/cm³	GPa	MPa	um/m-K	m/s	m	seconds	m
Steel SAE980x	7.9	200	650	12	5000	8400	40	120
80% Kevlar
80% Spectra
80% nanotube

LinearCables

Linear Cables