Advanced Kite Killing
AWE arrays must douse quickly & easily in an emergency. Prompt killing
minimizes damage and risk in many failure-modes. Proposed FAA regulations
require fast evasive action by a sUAS to give right-of-way to manned
aircraft in shared airspace. A common kite problem is for wind to increase
unexpectedly and overpower retraction force. Back-up landing methods are
needed.
Kite killers for single traction kites are well known, but killers for
arrays (trains and arches) hardly exist. Every lifter kite in an
array might have its own killer as part of a hot-swap capability.
Multiple killer tag-lines can be rigged as leaders along a main kill line
whereby ongoing retraction of the mainline kills each kite in sequence. A
parallel array of tag-lines can kill all kites at once, but considerable
force is required. At some point a network of kill-lines becomes a
nuisance. Distributed servo actuation becomes favored.
Another major kill method is "walking down" a kite. Compared to winching
in a kite against the wind only a fraction of effort is needed to trolley
downwind pulling the kiteline down until the kite is landed. A related
method is for a kite vehicle to run downwind allowing its winch to more
easily take in line. Similarly a dipping boom can be repeatedly tipped
forward suddenly while winching to reduce the retraction force required.
This is how a fishing rod is worked to bring in a fish more powerful than
the reel by itself. These are options for the sort of fast evasive
maneuver called for by proposed sUAS regulations.
Large soft kites can be killed by hand when they touch down. One runs up
from downwind, just clear of the kite's scope, to wrestle down the fabric
into a ball. Grabbing a kite by the tail is a sure way to "trip" it down.
Pulling aft lines to windward, slacking windward lines, or pulling in one
side all kill a kite.
An ancient method is to kill a kite with a kite by cutting its line with a
knife or abrasive. A kite pilot may carry a hook-knife or for a huge
hawser keep a machete, saw, or ax handy. Gomberg's quick-release for giant
show kites simply releases the line. A cutaway kite drifts downwind
landing some ~4x altitude, so it needs considerable space; and there
is a risk the cut tether can catch on obstacles or drag objects, extending
flight. KiteLab's kite killers release a kite's side-bridle or fore-bridle
line by a pin-release actuated by tag-line or remote/auto control. The
kite comes right down and remains attached to its anchor.
FairIP/CoopIP
~~Dave Santos
May 19, 2010
M1542
Comment and development of this topic will be occurring here.
All, send notes!
Terms and aspects: stopping the flight of a
kite system, side-bridle line, fore-bridle line, extending flight, kite
killer, tag-line, walking down a kite, sUAS, small unmanned aerial
systems, single traction kite system, AWE arrays, douse a kite system,
runaway kite system, damage potential of runaway kite system, damage
potential of an uncontrolled long lifted tether, kill a kite with a kite,
failure, failure mode, tail, tripping a kite, right-of-way, regulations,
retraction force, array-killing method, arch-killing method, train-killing
method, multiple killer tag-lines, lifter kite, array's lifter kite,
hot-swap
capability, parallel array of tag-lines, kite's scope, sequential
killing, distributed servo kite-killing systems, downwind-moving kiteline
winching vehicle,
LinKnife, soft kite, hard kite, kite wrestler, kite grabbers, kite
catchers, cutaway kite, cutaway kite system, drift, aft lines, windward
lines, dipping-boom AWECS, evasive maneuver, hand killing, kite pilot,
hook knife, hawser, guillotine, machete, ax, saw, explosive cutter, cut
tethers, pin-release, actuators, remote control of servos in kite-killing
operations, kite capturing, kite retrieving,
Related links:
Commentary:
- Aerial balling for quick dropping?
- Aerial flagging for quick releasing of lift/drag?
- Higher lifter kite system to capture killed kite system to avoid
ground contacting of killed system?
- Morphing kite sail body to glider at kill time, followed by GPS
robotic gliding to port?
- Disconnect tether at kite sail body if breakaway occurs; follow with
morphing to robotic gliding to port.
- Costs of killing kites?
- Anticipating risks.
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