Falconry training and technique two parts that twist freely, each with a metal hoop on the end. The swivel may be traditional, or modified. The modified swivel has much larger metal hoops than the traditional. While swivels have been made of cloth or other materials in the past, most modern falconers use metal swivels. See Falconer's knot for more information about tying off the bird to the glove. When using Aylmeri jesses, there are usually two sets of straps: the mews straps, for manning and tethering the bird, and flying straps. The flying straps are lighter and smaller for hunting; the mews straps are
Electrodynamic tether momentum) into electricity. In principle, compact high-current tether power generators are possible and, with basic hardware, tens, hundreds, and thousands of kilowatts appears to be attainable. NASA has conducted several experiments with Plasma Motor Generator (PMG) tethers in space. An early experiment used a 500-meter conducting tether. In 1996, NASA conducted an experiment with a 20,000-meter conducting tether. When the tether was fully deployed during this test, the orbiting tether generated a potential of 3,500 volts. This conducting single-line tether was severed after five hours of deployment. It is believed that the failure was caused by an electric arc generated