[JoeF]

I have been collecting materials during my neighborhood works. Sorting those materials while discarding some has resulted in a substantial collection of bamboo sticks, wood sticks, plastic sticks, fiberglass sticks, iron sticks, aluminum sticks. There is in my future a bamboo-using busable HG, a wood-using busable HG, a plastic-stick-using busable HG, a fiberglass-stick-using busable HG, an iron-stick-using busable HG, and an aluminum-stick-using busable hang glider. My notes indicate a busable HG using a type of stick that I have no collection for; I will either purchase or make carbon-fiber-epoxy sticks for a CF-based busable HG, but the investment will arrive after getting some successes from the other experiments; I do aim for low mass in some matured busable Dockweiler-only conservative HGs. The present chapter of my life might be dubbed: Busable-Wing Era (BWE).

Busable HGs will be quite trekkable using various methods: travois, wheels, back-pack, etc. Busable hang gliding culture may grow. There may be busable hang gliding clubs. No car, no truck, no van, but just public transportation and even politeness presence on regular city buses ....

[Bob Kuczewski]

Alpha_Hack_Saw_5.jpg (53.29 KiB) Viewed 1159 times

[JoeF]

Alpha 210 Manual

Someone might hacksaw an Alpha 210 or Alpha 180 to get a short pack to fit present topic. My estimate is that the result at first blush would involve a new higher weighted wing. The volume of the result at the new higher weight might be acceptable for some kinds of toting and flying operations. My first guess is that the result would be a wing heavier and less polite than my first aims relative to common city-bus riding.

Your offer of the Alpha 210 for the general topic project is generous and respected with gratitude.

The movement hinted by this topic does not require soft rigging lines, but such is one of my core first-era aims. My personal first-era aims are for wings that will be under 30 lbs empty weight and have quite polite bus presence. Flight performance of Alpha 210 may not (very probably not!) be matched by my first-era versions that I am coming up with. Flight performance is for my first efforts much secondary to low mass and bus-presence ease and politeness while having tolerable assembly and packing times.

The Alpha 210 is a fine wing. Stock: 51 lb empty flying weight. Hacksaw mods with coupling would advance that weight upward. Chance of kinking the Mylar insert would increase in a mod history. Chance of kinking hard lines for the short packing would increase. The manual linked is instructive for the stock wing; short packing via hacksaw mod would deepen the manual guards.

[JoeF]

Triangled-mesh net as a basis for a ripstop low-mass sail? Laminate a low-mass fabric or low-mass plastic sheet to the triangled-mesh net.
What might be commercially available in such kind of netting? Maybe a workaround: bond two flat nets to each other after turning one net at 45 degrees to the other first net?

DIY net and then DIY lamination? Dyneema line for the triangulated mesh? Triangles of 6 inch sides? How to form the net junctions? Superglue?

[JoeF]

DIY net of Dyneema string?
Most common nets are quadrilateral or hexagonal celled. One found "triangle" celled net seems actually to still be quadrilateral when fine investigation is done. So, DIY net suggested itself. If one started with a commercial product net of quadrilateral cells, then one possibility is to add string lines to form diagonals to the cells. But I am after a large celled net with triangles about 6 inches on each side; and I want to avoid knots in the base net. Aim is low mass for the HG sail. I want the string net to transfer the cell flight loads; having one cell be so isolated will permit using thinner sail material for each cell.

Let the equilateral triangle cells be about 6 inches for each side. The junctions are three-string stacks and thus the valence at the junction is six. The stack of three strings could be sewn; mark the joins while the strings are in light tension; use the marks to hand sew the joins by using a small fid to end the three strings marked at the join; find a satisfactory closing knot for the join; cut off excess joining thread; maybe dab the join with silicon, not sure yet. While the perimeter of the macro net could be a light webbing, a holding frame might be used to facilitate lamination of thin-film Mylar; envisioned is a sandwich of two Mylar films that have the string net sandwiched.

SandwichTriangleCelledNet01.jpg (99.36 KiB) Viewed 1129 times

Mods of the above?
Consider other-than-Mylar to form infill of the triangle cells. The triangulated net will be carrying flight loads to the HG frame. Reuse of film materials found discarded in cities? If bonding captures the string edges of one triangle cell, then the flight loads of the small triangle cell will permit use of even thin paper. Fun to explore! Loss of some sail in some cells won't be catastrophic at Dockweiler. Patching might be easy; glue some notebook paper to the vacated triangle cell? Collect all those birthday and graduation Mylar balloons from the city's bushes; cut patches of the balloon film and in-fill the triangle-cell net.

https://keisan.casio.com/exec/system/1223266946 One cell will hold about 16 sq in of sail. Very rough envisioned load: 3 oz per cell's area; so, if a cell's sail can hold say 5 oz without burst, then game is on; ruptures will occur, but can be patched.

Back-of-napkin rough: 10x20=200 sq. ft. 200x144/16=1800 cells. 250 lb/1800 cells= ..... approx 3 oz per cell flight load, rounding up for safety factor.

[Bob Kuczewski]

DIY net of Dyneema string?

You always bring us interesting ideas, Joe!   

[JoeF]

https://www.toyota-global.com/innovation/partner_robot/news/202201_01.html
The Mothership Project
Toyota Frontier Research

ToyotaStudy.jpg (35.36 KiB) Viewed 1087 times

The fibers appear to me to be Dyneema.
================================================
Take special care to note their progress in making a new base woven fabric.
"Image 6: Comparison of the conventional and new base fabrics: because it is woven, the new base fabric has a uniform density"
==============================================
I do not see splinted tactics, only high pressure; I see dependency on inflation without splinting. But, maybe they did splint compression members; maybe not.

[JoeF]

Not much to say on following yet:

2TipExtensionIdea.png (4.24 KiB) Viewed 971 times

[Craig Muhonen]

Hi Joe,
The graphics on your "5' packed" posts are super, and maybe you could visualize this and make a graphic.
Here is an idea that has been lingering in my mind about
the battens in the wing of a glider, mostly the outer wing,
and why couldn't each one change shape, and "curve" the wing slightly different, like trim tabs, or servos, or tip stallers.
I don't know how they could be built, if they haven't been already,
but their "connection" to the pilot's helmet would be key, and a programmer could write software.
I am thinking that if these new battens and helmet, could be "retro fitted" on to any king posted glider, and be made cheap enough, pilots would try them out.

now it's not lingering any more.
Craig

[JoeF]

Muhonen Adjustable Ribs

Adjusting method options?
Wireless? Voice-activated? ???
Control line to pilot? Helmet, hands, torso, tether,
Locally passive-reactive?


Brainstorm methods of adjusting the form of the rib:
Shorten rib
Lengthen rib
Alter curvature of rib
?

A first effort: "camber by way of a controlled-length bow string"

CamberControlledViaVariableBowString.jpg (22.71 KiB) Viewed 932 times