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
Momentum exchange tether field such as around the Earth, a conducting tether can be configured as an electrodynamic tether. This can either be used as a dynamo to generate power for the satellite at the cost of slowing its orbital velocity, or it can be used to increase the orbital velocity of the satellite by putting power into the tether from the satellite's power system. Thus the tether can be used to either accelerate or to slow an orbiting spacecraft without using any rocket propellant. When using this techniques with a rotating tether, the current through the tether must alternate in phase with