News from HangGliding.org

Syndicate content Hang Gliding Org
Updated: 2 hours 1 min ago

Q&A, Learning to hang glide :: RE: How often do you replace your carabiner?

22 April, 2017 - 20:45
Author: carlsonmjc
Posted: Sat Apr 22, 2017 12:45 pm (GMT -8)

A good source of Biners, are rescue supply places. I replaced a 32 kn Stubai with 72 KN , 16000lb plus, from one of these places.

Hang gliding Videos :: RE: Sycamore Ridge + Industrial/Urban Soaring 2017.04.19

22 April, 2017 - 20:18
Author: NMERider
Posted: Sat Apr 22, 2017 12:18 pm (GMT -8)

Lucky_Chevy wrote: Thanks for posting. How do you like the pitch adjustment system in your Tennax 3?
My Tenax 3 came with a kick ass pitch adjuster which failed at least 6 times in flight. A real piece of garbage. I rebuilt or corrected every single component and now it's great. I've gotten many horror stories and complaints from other owners with similar complaints plus more while many other pilots have been happy. The Tenax 4 seems to have corrected everything wrong with the 3. I don't own one and won't swear to it. Harnesses are a major bone of contention in this sport. Sadly.

Anyhow I'd suggest getting the friction pitch system. Pilots seem generally happy with those.
_________________
http://www.youtube.com/glidela

Hang gliding general :: RE: A theory of how lift is generated by a wing is debunked.

22 April, 2017 - 19:25
Author: hgldr
Posted: Sat Apr 22, 2017 11:25 am (GMT -8)

Doug,
That's a good video from Boeing's Doug McClean. I left a note on the youtube comments reflecting the miscperception which we always hear, that speed causes low pressure for some unknown mysterious reason. Simple fact which McClean points out is that differential pressure on opposing sides of each infinitesimally small parcel of air (or of ANYthing for that matter) cause acceleration, and the integral of acceleration is velocity. This is actually what Bernoulli originally wrote but, repeated incorrectly in many books is that, "speed causes pressure".
- Darrell

Hang gliding general :: RE: What to do with well-used or very old gliders--

22 April, 2017 - 18:10
Author: dayhead
Posted: Sat Apr 22, 2017 10:10 am (GMT -8)

magentabluesky wrote: I am vacating my hanger in Big Bear and need to send four gliders to the retirement home:

AMF Voit Proto-type Glider (standard 20”) missing some tubes.

Epper Standard

Wills Wing Alpha (1978) 215

Up Comet 165

Would not want to fly them any higher than I would want to fall.

They would make great displays.

I also have Hang Gliding magazines dating back to 1978, boxes and boxes.

Michael

If you don't find homes for them I'll gladly add them to my pile. Those who grew up with Erector Sets and Tinker Toys will find a good use for the stuff.

Hang gliding general :: RE: What to do with well-used or very old gliders--

22 April, 2017 - 18:08
Author: dayhead
Posted: Sat Apr 22, 2017 10:08 am (GMT -8)

I got a pile of old diver frames under the house. I'm thinking there's enough good stuff there to:

Build a greenhouse.

Make a giant windchime to hang from a tree. Combine with an array that gets sound from wind blowing over the tube openings, saw something like that on the 'net but can't remember where.

One helluva TeePee.

A long lasting fence.

The frame for an airchair 103 glider. Would be interesting to see if it could be done using existing lengths and bolt locations.

I've used some of the pile to make a couple racks for cars.

A swing set.

A small Ferris Wheel for kids.

Create a dangerous new sport of riding a Ferris Wheel down a hill.

Fill in the ____________.

Hang gliding general :: RE: Carbon or Aluminum outer leading edges - Stiffer the better?

22 April, 2017 - 17:34
Author: Wonder Boy
Posted: Sat Apr 22, 2017 9:34 am (GMT -8)

waveview wrote: Thanks Red, that does make sense about the location of any weight saving.

I was also reading that a carbon outer can also allow a greater safety margin for lower sprog settings (than an aluminum outer) as the carbon outer is less likely to twist if the sail loads down on the sprog. This may be another plus for carbon in top end competition flying. I doubt if any pilots would like to put this theory to the test though.

Also helps the resale value of the wing down the road.
_________________
Mike

Everyone who lives dies, yet not everyone who dies, has lived.
We take these risks not to escape life, but to prevent life escaping us.


https://sites.google.com/site/colcenteroflift/

The camp fire :: RE: New HG/PG focused Brewpub

22 April, 2017 - 17:08
Author: TomGalvin
Posted: Sat Apr 22, 2017 9:08 am (GMT -8)

I only put our feeder out last weekend, but we have one already on the dole.
_________________
Hummingbird rancher

Hang gliding Videos :: RE: Sycamore Ridge + Industrial/Urban Soaring 2017.04.19

22 April, 2017 - 16:41
Author: Lucky_Chevy
Posted: Sat Apr 22, 2017 8:41 am (GMT -8)

Thanks for posting. How do you like the pitch adjustment system in your Tennax 3?

Hang gliding general :: RE: A theory of how lift is generated by a wing is debunked.

22 April, 2017 - 14:58
Author: dbotos
Posted: Sat Apr 22, 2017 6:58 am (GMT -8)

Here's a short related video I found interesting:


Link

Incident Reports :: RE: Hook Knives Save Lives!!!!

22 April, 2017 - 14:47
Author: dbotos
Posted: Sat Apr 22, 2017 6:47 am (GMT -8)

Here are some commercial models I came across when looking at designs:

https://www.square1.com/manufacturers/square1/p1155.asp

Ground-based hook knife practice would probably be a good thing to work in with a parachute clinic or just in the back yard. Pilots that tow could practice cutting bridle lines and everyone could do hang loops (1) hanging in harness from tree branch and (2) with hang loop tethered closely to ground (to simulate being on top of flipped-over glider). For the latter, you could use an auger-style ground anchor or just have helpers standing on each end of a piece of pipe laying on the ground that simulates the keel.

Hang gliding general :: RE: A theory of how lift is generated by a wing is debunked.

22 April, 2017 - 14:47
Author: RobertKesselring
Posted: Sat Apr 22, 2017 6:47 am (GMT -8)

ksglider wrote: Here is a very interesting video. It's a little long but well worth watching.

I saw this a few months ago. When I saw this thread, I thought I should try to find it again and post it, but hadn't gotten around to it yet. Thanks ksglider for posting it.
_________________
Do something today to inspire a new pilot for tomorrow!

Incident Reports :: RE: Hook Knives Save Lives!!!!

22 April, 2017 - 13:22
Author: dbotos
Posted: Sat Apr 22, 2017 5:22 am (GMT -8)

Doug,

Thanks!

The question of straight through versus slicing/sliding cutting would be interesting to compare with some experiments. You could replicate a small portion of whatever head design you were thinking about using (enough to hold the blade and interface the material being cut in a guide slot) and then use vise grips as a temporary handle. I did a little testing with this one on some utility rope I had laying around (around 1/4-5/16" diameter, one was hollow braid, the other twisted strands) holding one end in a vise and the other end by hand and it cut pretty easily. Some real bridle and hang loop material would probably be a better benchmark.

The ends of the guide slots start as 1/2" holes and flare out from there as you go toward the blade edge, so a 1/2" diameter rope or 1/2" thick worth of webbing should fit in there.

Getting back to angled blades, I had sketched up a design at one point that used X-acto knife blades (they are slightly thinner at 0.020" than 0.025"-thick utility knife blades). Makes for kind of a small throat, but I guess you could angle them out a bit and increase that.

Hang gliding general :: RE: A theory of how lift is generated by a wing is debunked.

22 April, 2017 - 13:20
Author: ksglider
Posted: Sat Apr 22, 2017 5:20 am (GMT -8)

Hi All;

Here is a very interesting video. It's a little long but well worth watching. If one was ever to listen to anyone about this subject, then this man is the one.

https://youtu.be/QKCK4lJLQHU

Doug

Hang gliding general :: RE: Carbon or Aluminum outer leading edges - Stiffer the better?

22 April, 2017 - 07:44
Author: waveview
Posted: Fri Apr 21, 2017 11:44 pm (GMT -8)

Thanks Red, that does make sense about the location of any weight saving.

I was also reading that a carbon outer can also allow a greater safety margin for lower sprog settings (than an aluminum outer) as the carbon outer is less likely to twist if the sail loads down on the sprog. This may be another plus for carbon in top end competition flying. I doubt if any pilots would like to put this theory to the test though.
_________________
Don't let gravity get you down.

Hang gliding general :: RE: Carbon or Aluminum outer leading edges - Stiffer the better?

22 April, 2017 - 07:13
Author: red
Subject: Re: Carbon or Aluminum outer leading edges - Stiffer the bet
Posted: Fri Apr 21, 2017 11:13 pm (GMT -8)

waveview wrote: Is a carbon outer leading edge always better? It's an expensive option to save a few ounces in weight. Waveview,

I agree, but it is the location of that weight that really counts.

ANY weight savings at the wingtips will make a real difference in handling, as in the efforts required from the pilot to turn.
The stiffer tubing may set back the gains in handling, but I believe that most gliders can be "de-tuned" out there
to get back any handling qualities which could be lost to the stiffer tubing.

Tuning at the main body of the sail can increase the gliding performance, up to a point.
Tuning at the tips may only make the glider stiffer to turn, without much benefit to performance.
You can usually give away a little in tuning there at the tips, if it makes the glider nicer in handling.


_________________
Cheers,
........Red.........................
Pssst! New pilot? Free advice, maybe worth the price,
http://www.xmission.com/~red/
H4, Moyes X2, Falcon Tandem, HES Tracer, Quantum 'chute

Hang gliding Videos :: RE: Sycamore Ridge + Industrial/Urban Soaring 2017.04.19

22 April, 2017 - 05:49
Author: NMERider
Posted: Fri Apr 21, 2017 9:49 pm (GMT -8)

remmoore wrote: NMERider wrote: ...but doing Perfect Circles in the sky everything will turn out just wonderful.
I heard that if the circles are truly perfect, unicorns will arrive on rainbows and gently deposit you on a pink cloud of fluff. And in all modesty, the sport of hang gliding will live happily ever after thanks in no small part to my selfless efforts and viral marketing by the community.
_________________
http://www.youtube.com/glidela

Hang gliding general :: Carbon or Aluminum outer leading edges - Stiffer the better?

22 April, 2017 - 05:06
Author: waveview
Subject: Carbon or Aluminum outer leading edges - Stiffer the better?
Posted: Fri Apr 21, 2017 9:06 pm (GMT -8)

Is a carbon outer leading edge always better? It's an expensive option to save a few ounces in weight.
_________________
Don't let gravity get you down.

Incident Reports :: RE: Hook Knives Save Lives!!!!

22 April, 2017 - 04:19
Author: DMarley
Posted: Fri Apr 21, 2017 8:19 pm (GMT -8)

Dave,
That is seriously a bad knife.
A seriously bad ASS knife.
Nice! And stout!
The only thing I would think that would make it slightly better is making the blade edge at an acute angle to the cutting action, rather than being almost at right angle, just as you would cut a piece of material with a box cutter knife. If at a 90 deg angle, the box cutter razor blade will bind and tear the material rather than smoothly cut it. This is the same reason I do not really like the Benchmade-style hook knives as most of their cutting surface is at a 90 deg angle to the thick object being cut, especially if the material is something that takes up much of the throat area, such as a hang strap, or thick tow line. Though, I have never used a hook knife in dire straights, so I don't really know. I've seen how the Benchmade knives slice effortlessly through very thin material, but if that material is a large percentage of the throat width? Don't think it will be as dramatic a cut.
I'm sure Jon will tell you and me not to go redesigning the f---g wheel again. Whatever. I like your ideas.

Hang gliding general :: RE: What to do with well-used or very old gliders--

22 April, 2017 - 00:41
Author: waveview
Posted: Fri Apr 21, 2017 4:41 pm (GMT -8)

Doon gooning practice wings?
_________________
Don't let gravity get you down.

Hang gliding general :: RE: What to do with well-used or very old gliders--

22 April, 2017 - 00:31
Author: leesidelee
Posted: Fri Apr 21, 2017 4:31 pm (GMT -8)

One local ace pilot years back had tumbled his wills HP AT in some strong rotor. Too low for his reserve but at least he came out ok minus broken thumb. His keel actually took the brunt of the impact literally taking a core sample inside the keel of the rock it impacted.
Months later I saw his sail hanging in his living room as window shades. I asked: "is that your old HP?"
And Scotty A. answers:
"IT TRIED TO MAKE CURTAINS OUT OF ME SO I MADE CURTAINS OUT OF IT"