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Vertical-line AWE methods

Recent posts described vertical kitelines set by low-angle guy-lines to windward. It was shown that a wide-format kitefarm can be rigged to consist mostly of vertical lines. An application example of vertical lines was suggested, as halyards to suspend turbines & membrane wing-wills directly over their surface work-cells. Many such uses are enabled by the unique properties of vertical lines. They are gravity-aligned, wind-direction-neutral, & the shortest path to altitude.

Vertical is a new "crosswind" geometry for a tethered-foil to follow, as a vertical zip-line, pulley loop, or elastic-return line. Far more wings can operate in the same airspace, by plunging up & down as pumping-trains, than common back-&-forth AWE schemes allow. A light wing easily climbs a vertical line faster than the wind. The plunge back down is a high-speed dive, but under captive control, especially with elastic-return. Vertical self-oscillation, triggered by line-bow phase, is an elegant passive steady-state wing tacking mechanism.

A century ago Cody developed a clever system of graduated rings & cones on kites & lines as programmable stops & passes for sequenced launching. The "Austrian" theatre curtain is an upside-down vertical rigging model, with drawlines gathering or deploying material along sewn-in rings. Vertical line arrays lifted by pilot-lifter kites can guide complex 3D meshes aloft, just as traditional circus canopies ran up erected tent-poles by their bail rings. Unlike a circus tent, multiple levels of AWE structure can be raised in orderly sequence according to conditions, especially to conform to calm & storm. Return loops in the array interstices allow every flying component to be hot-swapped freely

Kites singly or in trains will happily reside on a vertical line, providing lift to the line without fuss, regardless of wind direction. This is not the weak lift of a high L/D kite near zenith. Vertical kite towers can displace rigid towers in many applications. Vertical-trains can rise from a packed stack in a small box & return there passively, by gravity.

The simplest vertical-line case is a single guy set at an angle shallower than the pilot-lifter's leader to pull a second line into vertical position. A vertical line can be dynamically anchored by by a castored cart or hanging teabag-mass, typically water or sand-bag free to be briefly lifted & dragged around ("tea-bagging").Three guys rigged as a shallow tripod can hold a fourth line vertical, as wind freely veers. Let a kiting Whiskey-Line be defined as a spacial case of guy-line; an adjunct or improvised guy-line to haul a vertical line or array into shape. (The usage is from commercial fishing where an extra trolling line was set over & beyond the standard lines "to pay for the whiskey")

Planar Symmetric Arrays (PSAs) do not veer around the wind compass like single-anchor AWECS. Vertical lines are natural PSA feature. Non-rotating arrays do not sweep large areas like single anchor AWECS, but are inherently constrainable to narrow corridors for forced-landing containment.

CoolIP                       ~Dave Santos             , 2010        M2392

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