Page 1 of 3

Hanging Arrangements for Weight-Shift Control

PostPosted: Wed Jan 21, 2015 12:34 pm
by JoeF
All are invited to describe various historical hanging-of-payload (pilot or orther matter) arrangements
in weight-shift-control aircraft (gliding or powered or power-off or kiting) (WSC, WSCA).

Image
Image
Image
Image
== Hang pilot body from shoulders when pilot is resting forearm on airframe.
== Hang pilot body from just a overhead grab of glider airframe.
== Hang pilot body from shoulders when pilot is hanging armpits on airframe.
== Hang pilot body from a fore-to-aft strap (two-point arch of strap); pilot sits on strap.
== For the John Worth hang gliders and powered flexible wings: Brace-hang payload mass between the front triangle control frame and a rear triangle control frame.
== NASA and Ryan hanging of payload via just lines.
== NASA and Ryan hanging with tension rigid members still universal-jointed at the airframe for WSCA.
== Hang pilot body from a short hang line; use a harness or seat at the terminus of the hang line. W. Simon in 1908 using the triangle control frame for hand-control of wing attitudes with WSC hung from airframe of foot-launch hang glider which featured a battened flexible wing; in later hang gliding renaissance, the same triangle control frame and hang-lined pilot would win high popularity in hang gliding and other WSCA.
== Alternative arrangements of the W. Simon basic one line is to have a group of many lines from the airframe to various points of a harness or seat; two lines, three lines, four lines, five lines, six lines, seven lines, eight lines, ...
Zee wrote:== Alternative to the flexible line that was extant in W. Simon's hang glider in 1908, is a stiffened line or even rod or tube still approximately universal jointed at the connection to the airframe. See sample hereon:
RigidHangTube.JPG
RigidHangTube.JPG (31.38 KiB) Viewed 6008 times

Early two stiffened beams or maybe ropes holding hung seat
Image


W. Simon in 1908 protected his arrangement by legal means. Mechanically this is about what is most seen today at hang glider sites.
Image

Eipper in Torrance using hang-from upper-under-arm; left corner of photo is Steve Wilson. Tail-keel hand launcher: ____________________ ?
Image


Other hang methods are invited to be described in this topic thread.

Re: Hanging Arrangements for Weight-Shift Control

PostPosted: Wed Jan 21, 2015 1:20 pm
by Bill Cummings
Joe, I made this swing seat back in early 1978. The “old” swing seat had only two ropes one on each side of the pilot. Mine had two runs on each side of the seated pilot.
Two pulleys allowed a pilot to push the base tube farther forward for a better flare.
Sorry for the poor free hand drawing with a touch pad.
swing seat.JPG
swing seat.JPG (47.31 KiB) Viewed 6006 times

(free to remove post)

Re: Hanging Arrangements for Weight-Shift Control

PostPosted: Wed Jan 21, 2015 1:40 pm
by JoeF
That is a welcomed arrangement BillC ... drawing is just fine ... elements are clear.

====================================================
Volmer Jensen was not the first, but: Once flying, then rest pilot mass on a single line that goes to a disc seat; the line hangs down in front of the pilot; the line goes to the groin and the disk seat is there for mounting after a first support from armpit or forearm support during launch run and launch. This was marginal-to-nil WSC as he depended on three-axis control by aerodynamic surfaces.

==========================================
Miller at the Great Otto Meet: armpit firm while firmly grabbing forward struts.
Upper shoulder and neck and head do not move much; mostly only the mass from lungs down get to change position for control.
Have a large-radius firm pad; this is for short glides.
MillerArmPitHandGrab.jpg
MillerArmPitHandGrab.jpg (24.61 KiB) Viewed 6006 times

Re: Hanging Arrangements for Weight-Shift Control

PostPosted: Wed Jan 21, 2015 2:22 pm
by JoeF
Igor Bensen's several kited-launched gliders hung the pilot from tubes that were in tension. He then had various airframe grabs.
The hung-mass WSC glider photograph hereon shows an airframe grab of a mini triangle control frame which frame was firmly coupled with the wing.
Looks like two rods at his back and one rod or tube in front; the three down tubes held his seat and himself; the three down tubes were in tension
during normal hung-mass free-flight gliding. The wing was an unpowered auto rotating set of blades. Gyrokite for launch and then gyro-glider for free flight gliding.
Think circa 1954 for his first adventure in such arrangements.
Image

Re: Hanging Arrangements for Weight-Shift Control

PostPosted: Wed Jan 21, 2015 10:17 pm
by dhmartens
It might be possible to suspend a pilot magnetically inside of a hula hoop arrangement.

Re: Hanging Arrangements for Weight-Shift Control

PostPosted: Thu Jan 22, 2015 9:57 am
by wingspan33
dhmartens wrote:It might be possible to suspend a pilot magnetically inside of a hula hoop arrangement.


In thinking about this, it could work, theoretically, to hold a (metallic) pilot in the circular magne-frame, but this frame would resist the pilot's motion sideways (away from of the center of the magnetic field. So, weight shift from side to the side would be resisted.

The other tough thing about this suspension method is the SERIOUS power it would require. :problem:

Not what I would call practical.

Oh, and the pilot would have to be able to be influenced by magnetic fields. The typical human being is not.

But hey, part of the idea is to think outside the box, right? :thumbup:

Re: Hanging Arrangements for Weight-Shift Control

PostPosted: Thu Jan 22, 2015 11:02 am
by JoeF
LimitElasticsRing01.png
LimitElasticsRing01.png (3.83 KiB) Viewed 5986 times


Limit-lines suspensions? Elastic return. Effort to move mass. Relax to return to trim position.

Re: Hanging Arrangements for Weight-Shift Control

PostPosted: Thu Jan 22, 2015 11:42 am
by wingspan33
Joe,

I've had a couple ideas along these lines. I'd have to dig up some old snap shots I have of a simple modification I developed of the keel mounted hang loop idea. I actually built and installed the device on a Delta Wing Streak, which I highly modified back in the early 1990s. It would be difficult to describe it here in words.

However, I've had a more advanced design concept in mind for a long time. It would involve a tear drop shaped pod/airfoil (let's call it the "Suspension Fin") that would be integral to both the wing and the pilot's "harness". It would join the two together and would be both flexible and quasi-ridgid. Imagine it (in horizontal cross section) as being ~ 18" long LE to TE and about 3" across at its broadest camber point. Its height, from wing to harness would be 3' give or take. BTW - This idea allows for NO control bar.

The pilot would actuate levers (associated with, and integral to, the harness) which themselves would act upon "tendons" within the Suspension Fin.

Each hand would control one lever - which would be located within close fitting "pockets" in the chest area of the harness.

Sliding both levers back would shorten the leading edge "tendon" in the Suspension Fin. This would swing the pilot forward. Sliding both levers forward would shorten the trailing edge "tendon" and swing the pilot backwards. Pivoting the left or right lever outward would shorten the respective left or right side "tendon" in the Suspension Fin. This would swing the pilot either to the left or right.

A foot stirrup (normally under tension during flight) would, when "relaxed", extend the rear Suspension Fin "tendon" lowering the pilot's lower body and feet (allowing the pilot to go upright) for landing. The opposite control would raise the pilot's feet (bring the pilot's body horizontal) after take off.

It wouldn't be all that hard to have the Suspension Fin be able to separate at the trailing edge and pop open (imagine opening a book) when the pilot rotates up for landing. This would create a large drag surface and help degrade the final glide angle.

By way of explanation, the weight supporting part of the Suspension Fin would be a rigid or quasi-rigid post that would extend from the wing to the pilot's harness/pod. There is a fairly simple way to have it utterly rigid (while in flight) but "relaxed" while ground handling the glider. And, it would incorporate an always semi-flexible joint at its connection point with the wing.

The wing would be designed with what would appear to be down tubes. But these would be retracted in flight. Without them there would be no support for the wing once it was on the ground. Imagine a larger scale (duel) version of a bicycle's kick stand.

The associated wing connected to this system would be fully cantilevered and VERY aerodynamically clean. I have also "invented" a unique structure for such a wing. I would place a guess at its weight at being around 30 - 40 lbs (excluding pilot attachment hardware).

All I need is a manufacturing plant, $100,000, and a few well educated design staff! :thumbup:

Re: Hanging Arrangements for Weight-Shift Control

PostPosted: Thu Jan 22, 2015 12:39 pm
by JoeF
wingspan33, .
[ ] I, for one, won't rest until I get an accurate mental image of all the aspects of the Suspension Fin ! Two readings, so far. I will come back for many other readings. Then I'll start sketching; others might do the same. Let's get a good hold of your vision! First blush, parts-when-wanted show ---and then hidden when not needed ... comes to mind. Rigidizing and de-rigidizing at will comes to my tongue. Dialed rigidity surfaces for me also. Feels like your vision gets rid of the profile drag of open arms and hands and down tubes. Let's press forward until your disclosure is robust; you have here dated disclosure record unfolding; the Internet lets a trace occur for disclosing novel matters.

Re: Hanging Arrangements for Weight-Shift Control

PostPosted: Thu Jan 22, 2015 12:39 pm
by JoeF
ForeAftStraping.png
ForeAftStraping.png (86.98 KiB) Viewed 5982 times
Minimal fore-aft WSC; mostly the system is aerodynamic-surface controlled.