US Hawks Hang Gliding Association

This topic invites the exploration of launching a HG flight from a fixed-anchor kite system. Reserve mobile-anchor kite systems for another topic.
Herein the anchor may be fixed in the sea or lake by various means. Or the anchor may be fixed in soil by various means. In any case, good engineering is needed. Proper notification to local air-traffic control (ATC) is needed as mass and tether length will trigger the FARs for such notification. HGs have been lifted by free balloons: Daniel J. Moloney in Montgomery's tandem-wing glider two centuries ago. [Note that the speaker holds many errors; the "blimp" was actually a kite balloon that kept its tether line but broke away from its mooring.] Clustered anchors and clustered tethers and clustered wings in the full kite system could bring aggregate lift and aggregate safety. Handy-sized wings in the kite system may be increased in number to face the lift needs in the ambient wind system. http://www.flyingmachines.org/mont.html
The topic hereon regards having up a fixed-anchor kite system; then have a HG and its pilot launch from the fixed-anchor kite system.

Winds aloft at the altitude of the launching point will be the at-HG ambient wind. Notice that the wing set of the kite system will be set usually higher than the station used by the HG. Notice the the kite system may consist of one or many wings; and the kite system may consist of one main tether or many tethers. And a good system is to have a kite-system-stop system at the ready; we do not want uncontrolled breakaway kite systems as occurred recently with a military JLENS kytoon which dragged a heavy tether producing some damage (which could have been much worse than what resulted).(See JLENS breakaway story) Upon breakaway it would have been neat to have a mechanism that would have cut the tether at the kytoon so cable dragging would not occur; cable dragging can do great damage to things and people on the earth surface. Secondary kite-stop lines dedicated to the one task of spoiling the flight of wings in the kite system form one way to stop a kite system or to depower the kite system for bringing the full system home.

The HG launch might be by one of several methods. Drop into the ambient wind faced at the launch altitude; notice that this kind of drop is far different from the drop from a free balloon, as a free-balloon drop has a dropped HG facing zero apparent wind at the start of free-flight. Differently, a HG at a tether station on a fixed-anchor kite system is facing the true at-that-altitude ambient wind. A second method is to have the HG with a lofted incline; the HG then could use the incline to increase launching apparent wind on wing before leaving the launch incline. One would want the incline to weathercock to keep the incline pointing into the ambient wind. Other methods may be conceived, perhaps.

How to get the HG to its launch station? Various methods here. One method is to attach the HG to a tether station and then let more line out until the HG reaches the desired altitude; this method slows the apparent wind on the system's wing set and places the kite system's wing set at new altitudes; this could bring in puzzlements as to upper wind speeds. Another method is to sail the HG up the main working line with or without the pilot. Another: Have a lofted pulley and once the kite system is settled, then use a a loop line through the pulley to bring up the HG with or without the pilot; a pilot could follow after things are settled aloft. Another method is to quiet the main kite system; while keeping the main tether at fixed length, have an auxiliary line at HG-launch station; pull that auxiliary line to bring down the tether; attached the HG and let the kite system flip the HG up to equilibrium kite-held flight.

Once the kite system is up; then launch one HG after another after another. Grand larger systems could hold two or more HGs aloft at once ready for launch.

Such systems could have the HGs wait for a thermal to arrive; launch into the thermal. Foot-launch off a lofted incline! Kite-system provided mountain!

Have visibility markers on the tethers to meet FAR requirements. HGs and other aircraft need to notice or see the tether system.

Notice how distinct the above arrangements are from vehicular or motored towing of a single HG is.


See: https://fedora.digitalcommonwealth.org/ ... 00/content

The following concept arrived yesterday just before sleep; I made some sketches (not shown yet).

Have three separate kite trains that hold whiskered soft wing element wings; one of the three trains would be left veering; one downwind stable, and the other would be right veering. Train-stop lines would be attached to guard agains runaway trains. The three main tethers of the trains would integrate through a gather ring; then the three lines would fan some to a wheeled ground spread bar and through the bar to a turret anchor. The wheeled ground spread bar allows weathercocking of the entire kite system. Somewhat below the gather ring would be another spread beam; just below the upper spread beam would be the beginning of an incline fabric (porous to wind, but with mesh adequate for hang glider pilot to run on). Have the incline go down a ways to a terminating spreader bar. The incline does not go any longer than needed for providing a foot-launch incline for the hang glider launch. Stay lines may assist the stability of the incline laterally.

Have to the ring a drop line to an anchored pulley; have the drop line attached to a parachute; have a depower line to the parachute center. Let the parachute pull down the ring and incline; this may be substituted by other means (friends, drop masses into well, winch cranked by helpers or motor, vehicle, ...). Hang glider pilot in clear readiness for launching steps on the incline. The ring and incline is let to rise as the lifting train elements are already flying; the hang glider pilot with wing is raised to altitude as the parachute is depowered under control to get rates of rise wanted. Finally fully depower the parachute; it will be ready for the next hang glider cycle. The raised hang glider may use ambient wind at raised incline position; foot-launch when ready. Perhaps the pilot will wait for a passing thermal.

The tethers will be made visible per FAR guides. Airspace for the lifter kite system will have received a covering NOTAM via ATC. The kite trains will have AoA control lines to help lower pressures upon increase of the ambient winds.

To pack away the portable mountain hang-glider incline lifter kite system, depower the wing elements of the trains; gather the system and store the system at club base or in road vehicle.

Launches may occur one after the other. Incline altitude may vary by choice. The system might be a kite-system "mountain" for the flatlands.
Over-ocean systems may be designed; compatible water-worthy hang glider wings may be specified.

Care for the integrity of the tethers and anchors. Match train wing-element count to the winds. Club team is to master operations of the system.

Notice that the hang glider pilot walks or runs down the raised incline into the ambient wind at rates needed for good launching. Notice that the upper winds will often be stronger than what is known near the ground. Notice that the total kite system is flying because there is some wind; this makes the hang gliding launch very different from being dropped from a free balloon.

Having a stable lifting kite system that with weathercocking lifted incline would bypass towing-launch challenges. The hang glider pilot could experience natural foot-launching using the lofted incline. Towing vehicles would not be needed. Towed lockouts would not be part of the story; towing timing and weaklinks would not be involved; powered aircraft towing of HG would not be involved. Roads would not be needed. But mastery of the kite system would be baseline matter; inspection and maintenance for the kite system would be needed. Safety margins would be built into the involved lines and parts. The system could be used over and over and over again. When the wind is too calm for cascading the train to fly, consider other methods : ); but note that calm on ground does not mean calm above; using slave pilot kites to cascade launch kite trains is a tactic; get the pilot slave up by various methods; then once the slave wing is up, let that slave lift wing elements of the train into the non-calm winds aloft; gradually enough lift may be obtained to pull up enough train elements into the adequate wind to bring on the lift needed to hold the hang glider incline.

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This is a very promising line of research Joe!!!

Since we'd be sending up a pilot with their own glider, we should be able to use that as part of the kite system.

I think there's a picture of Bill Cummings being kited somewhere on this site. In winds like we saw at Dockweiler, that would work without any kite assist. But since such winds are rare, the kite assist would greatly expand the operating range. The AoA control and "depowerability" that you mentioned would make such a system much more practical.

Give Terry one of these.

BobK's suggestion that the HG wing could play a direct role in a larger launching kiting system spawns some notes:

1. Yes, worth full exploring!

2. One favored opportunity is to have the HG pilot ever immediately ready to move forward on the rising incline into a free foot-launched HG flight. The joy of foot launching may be in focus. Mods removing the free foot-launching action may still be very interesting; see next note.

3. A non-incline method now comes to mind springboarding from the tease of BobK's suggestion. Here I describe what just came to mind: Have the kite system consist of just a left-veering and a right-veering kite train bridged by a special line set between the left train and the right train. The special line set that bridges the left and right trains consists of two line segments of equal length; one segment is a left segment that roots at the left train; the other segment of the bridge roots at the right train. The two segments forming the bridge meet onto one release mechanism at the centered hang glider wing. The hang glider wing is thus kiting and aiding in the total kiting effort as suggested by BobK. As the HG pilot decides to release the bridge line segments, those line segments fall and drift AND get pulled aside, one with the left-veering train and the other to the right-veering train. Hence a broad open space in front of the HG quickly develops allowing free space for gliding the HG away from all lines. This method does not use an incline, but simple release-away from a kited HG. Cycles of use may be provided by some of the techniques described in one of my above posts (depower some, pull down those bridge segments and reconnect to the next HG; kite as possible the next HG between the two veering trains (kiting increases with altitude normally as a wind gradient is often present).

Of course all of this assumes that any kite HG launching system stays stable during the time it is being used. This pretty much confines it to coastal wind areas of fairly smooth airflow.

I can just picture such a kite system out at my desert place where I see peoples flags all pointing in different directions at the same time.

Frank

Hi Frank,
The reason for involving kite trains is to get an aggregate stability over a tall swath of the winds. One would want there to be a prevailing wind; thermals will disturb some of the elements of a kite train, but the long trains bring aggregate grab that gives time for releasing the hang glider. If all goes to a situation where support won't continue, then launch the HG.

There are a few issues to be resolved before this becomes a reality, but I think it's great that there are people interested in extracting energy from kites to help move these technologies forward.

Thanks Joe for bringing these ideas forward!!