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By Lazypilot
#402521
[quote=magentabluesky
It truly is amazing how agile the Condor 330 is with that much square footage and span, just add more billow. I could never have imagined a training glider to be that much fun to fly.
Be Happy!!
[/quote]

I know I sound like a grouchy old curmudgeon, but in truth I'm happy. I remember way back when the WW Condor was new on the scene, and we had a antique glider meet at Dockweiler. I got to fly a Seagull 3 and a 11 Meter, also an extra span Easy Riser, a Bamboo Batso that had a healthy right turn in it. Everyone was crashing it, and I grabbed it and said "Yeah, I had a Pliable Moose with a right turn, this is how I had to launch it" and proceeded to launch with the left wing way down, as I got airborne it was starting to level, and just as I ran out of airspeed altitude and ideas she was starting to turn right. I got the longest flight.

I flew one of those Bennet kites with a psychedelic paint job, A Wills standard production # 15, and several others.

When the breeze picked up mid-afternoon I tried the Condor, and my diminutive stature paid off as I got a good 25' over and made many passes, until I was told that I needed to share the kite. It was fun, and I hope to get back there soon. I do appreciate the changes made to the rules, one of my many dreams is to build something like a Hang Loose, but do it Wright Bros style, right on site and fly it.

I followed a link to the OZ Report circa 2008 and relived a discussion not unlike this thread. Has anyone installed a lever link and reported on it? A guy named Brett was active in that thread and had flown his own version of it, saying it was effective. I'm afraid that he passed away here a few years back, may he RIP.

Most pilots contributing to that thread and this one seem to prefer flying prone, and would like something that compliments that style of flight. The more I think about it the more I like the idea of a comfortable ride in a fuselage of sorts, and perhaps with the ability to go from seated to prone, but definitely for sure the ability to lay back in a more reclined attitude for drag reduction.

Over at a friend's place the other day I tested an outdoor patio chair that worked like a Lazy Boy recliner, only it was built very light. But I could sit in an attitude much like a nice car seat, and then lay back in a nice reclined position. Maybe he'll sell me that chair...

I think that a Easy Fly thing with that feature and good streamlining rigidly attached to my Sensor is the way for me. I just need to figure out how I want the mechanics of control to work. I had a fun little daydream where I was sitting in the thing and I had in my hands a big old steering wheel from a big 1950's era American car. It even had one of those knobs on it.

Taking that further I would have foot pedals, not for yaw control but like a car, with a "gas" pedal that would trim the glider faster, and a brake pedal that worked the wheel brakes and lowered flaps. Pressing really hard on the brake pedal would deploy a drag chute.

I have a bundle of old straight battens to try making a model of the fuse with. Need to find some small screws and nuts.

Thanks to all contributors, keep up the good work.
By bickford frederick
#402526
I believe lovetosoarus was another username Brett used on forums.

Several years ago I was trying to imagine how to design and build a variable sweep wing. I was advised to build a model and test my ideas. I started learning about Reynolds numbers and found there were many other equations for dimensionless numbers and got overwhelmed. Deborah number (De) for example. holy crap.

We need to figure out a good method to vary chord length a bit.

I imagine someone should be thinking on the environmental impact statement and write a report up for this better ultralight.

I’m still aiming for a 50 pound glider that will fit into a 9 foot long shipping container being able to carry a passenger and or cargo and some propulsion eventually. Without a passenger we’ll probably be able to sneak it into 103 regs for about 3-6 months lol..
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By entelin
#402534
It seems to me that the first thing to do would be to change the Class 1 rule to a wingspan / weight category just like every other fai class. Why have a rule that directly attacks innovation instead of categorizes gliders based on the things that directly relate to performance. Am I wrong?
By Lazypilot
#402535
entelin wrote:
Tue Mar 06, 2018 12:11 am
It seems to me that the first thing to do would be to change the Class 1 rule to a wingspan / weight category just like every other fai class. Why have a rule that directly attacks innovation instead of categorizes gliders based on the things that directly relate to performance. Am I wrong?
Hell no you aren't wrong! That rule restricting how our gliders could be controlled was Ok when it was written and gliders were all billow cruisers. But along about 1980 it began to look like it would hamper further development of the "Sail Glider".

It blows my mind that in the year 2018 we use a sailboat main sheet block'n'tackle to determine if we can glide or steer. It was when that thing was developed that it became apparent that a rule change was in order. But like everyone else, I went along to get along. I occasionally brought it up, but was called a pussy so I shut up. I apologize for being cowardly, maybe it's the pu--ies that find better and easier ways of doing things. I've been told that if you want to find the best way to get a job done, put the laziest guy on it, he'll find a way.

The VG is a ridiculous thing to have on a glider. I'm ashamed of myself for not getting busy finding the right solution to the problem 38 years ago, instead of using this stop-gap band-aid for so long.

Another thing that blows me away is how many pilots think that there's no problem, it works just fine, if it ain't broke don't fix it, blah blah blah.

Well it sure as hell is broke. But I'm confident that with enough publicity about it a really ingenious solution that is light, cheap, and simple will come about. Where there's a will there's a way. I'm dedicated to thinking positive, that better handling is just around the corner.

Keep this thread going, advance your ideas even if you're not sure it is a good one. The inventor will be inspired by an off-hand comment that turns on the light bulb hovering over his head, all clues have value.
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By entelin
#402540
I would never claim to have great knowledge of aeronautical engineering, but it certainly would be a shame if such an attitude is the only reason why it's never been changed. Frankly calling anyone that hang-glides a "pussy", is a special level of idiocy at it's face. Doubly so if it's used as an excuse to prevent exploring design improvements.

Now it could be that a pure weight shift design IS in fact the most competitive possible at our wingspan and weight. Even if that's the case, the rule could still change to a wing span / weight model, and nothing would change in the competitive scene. But at least it would remove a potential roadblock.
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By Paul H
#402542
The VG on a modern glider isn't ridiculous at all if you stop thinking about it as just some kind of accelerator pedal for the wing. A very useful and often overlooked purpose for it is to use it as pitch trim just like in a powered aircraft. When you are thermaling you can set the VG to trim the glider to stay at the desired angle of bank with no bar pressure to work against. It's much more functional than some people realize. If you just leave it at one or two settings you will never get the best use from it. Also, the newer wings are very maneuverable with VG on.
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By magentabluesky
#402554
Lazypilot wrote:
Tue Mar 06, 2018 2:14 am
The VG is a ridiculous thing to have on a glider.
Mario wrote:VG or variable twist is a very cool plastic solution for getting closer to the optimum twist. This is why there is sometimes an argument as to the right amount of VG to use when trying to get the best sink rate.
There are many that have the misconception the glider is going to perform better with full vg on at all speeds and angle of attacks.

Mario understands the concept, higher angle of attacks (slower speeds) require more twist thus less vg to be more efficient.

The ridged wing SWIFT uses the very same concept, but utilizes flaps for varying twist instead of a vg. . (because it is not a flex wing)
The penalties associated with too much twist were eliminated by changing the effective twist with trailing edge trim and control surfaces. . . . .This use of the inboard flap surface for pitch trim gives the aircraft its name. . . . . the BrightStar SWIFT stands for Swept Wing with Inboard Flap for Trim.
Maybe Steve Morris will chime in on the subject. Development of the SWIFT

As Mario said the flex wing with "vg variable twist is a very cool plastic solution for getting closer to the optimum twist."

Without any actual calculations or measurements, but just eye balling twist on current vg hang gliders I would say they actually could use more inboard twist at the root. The Culver Twist profiles calls for the majority of twist in the first 30% closest to the root and very little twist in the outer 60%. The flapped Sensors are probably the closest hang gliders to the optimum Culver Twist profiles.

With modern electronic flight recorders it should be easy to document flight performance with variable twist (vg) and angle of attack (speed) in calm morning air.

VG is great on a glider! Pilots need to learn how to use it for maximum performance.
Paul H wrote:If you just leave it at one or two settings you will never get the best use from it.
By Lazypilot
#402563
The VG system is definitely valuable for some things. When I wrote that it is ridiculous, I was trying to get across the point that when the VG was created was the time when we should have taken a second look at the competition rules requiring weight-shift only, which I must admit has resulted in some really good engineering by our designers, but if you will kick back and relax and try to imagine where we might be today if instead of a VG we had continued working on some means of amplifying roll control.

I know that the latest offerings do handle decently, if you're only comparing them to Hg flex wings that came before. But when compared to aircraft that have aerodynamic control surfaces they don't rate well at all.

A couple years ago I was kindly allowed to demo a 136 T-2c for a 3 day weekend, and flew it several times in various conditions. While it had a lot more glide angle than my king-posted 136 flapped Sensor, the handling was about the same, yielding a comparable stick forces to roll rate ratio. I said the VG is ridiculous because the roll rate to stick force ratio has improved so little in --what--37 years or so? It boggles my mind that we place so little value on control of these things.

I'm having a bit of trouble trying to make clear just what it is I'm wanting to say. I'm gradually realizing that the majority of Hg pilots are satisfied with the choices available to them. So I start these topics to get a feel for how many other pilots see things in the different light that I see in. And to reassure them that they aren't alone, and thereby encourage them to speak up. I can assure you that it ain't easy to be the odd man out, to voice a minority opinion.

My "complaint" ( I don't like seeing myself as a complainer, but if the shoe fits...) is that we have so little choice. Sure there's quite a few different gliders, but the trouble is that they really aren't very different from one another.

They are all positive G only aircraft. To my knowledge there are no Part 103 gliders available for purchase that can be flipped inverted by a rogue wind and simply maneuvered back to normal flight, still in an airworthy condition.

And I see no good reason for that. All I can do is hope that we get another choice of glider configuration, one that doesn't throw the pilot around the trailing edge and up on top of the wing if he gets tumbled, whether by turbulence or a botched loop. A glider with a comfortable seat built in, no $4K harnesses required.

When hang gliding first got started I thought it was the cat's pajamas, the best thing since sliced bread. ( I've often wondered what the best thing was before sliced bread ). I was enamored of the aft-swept flying wing, and made a lot of models, culminating in the Sling Wing. That toy enabled getting a glider up high enough that it's characteristics over time could be observed and analyzed. This allowed me to explore the effects of sweep angle and other parameters.

I thought that the pure flying wing was the best design for Hg for many years. But eventually I started questioning that concept, although for low performance novice type gliders it may still be the way to go, I feel that for high performance flying in big air it may just be at a limit.

When anyone thinks "hang glider" they get a mental picture of the swept back flying wing. I'm trying to dislodge this from peoples minds, because it's my personal belief that a straight winged glider can maybe get the job done for less $ and weight.

Yes, it will need a tail or canard, but that's Ok, because a glider with more over-all length will be more tumble resistant. And some of the previous posts were about twist distribution, and for aft-swept wings that is important, at least it's more important than I think it is for straight wings. The problem with swept wings is the coupling of twist with pitch stability. This can be a limiting factor, for example look at what it takes to maintain the twist in the right direction when the AoA goes negative. Sprogs and washout struts require a really beefy airframe, built stronger and heavier than it really needs to be, and the reasons I feel this way about that are the videos of structural failure when negative G loads are applied to it.

Sure, they hold up Ok on the test truck, but what about Wolfie? He didn't violently tuck to inverted, he was simply rolled over, and the glider snapped in two like a matchstick. Perhaps the vehicle testing isn't representative of what real world negative G encounters are.

A straight wing divorces twist from pitch. It need not be built to have the torsional rigidity that the swept wing must have to survive. If it doesn't need to be as strong, it can be lighter. The weight savings from disposing of the sprogs and the VG can be spent on controls and a stabilizing surface, whether it's in the front or rear or both.

A glider that contains the pilot enough to maintain airworthiness even when inverted will have more versatility. As it stands, only a few highly experienced and skilled pilots can safely perform aerobatics. While most flyers don't care for aero, a glider that can perform aero safely will also be safer in big air turbulence, which any XC pilot would appreciate.

We started with a basic concept: An aft swept wing with the pilot suspended several feet below it. It was simple and cheap. Positive G only made it even simpler, theoretically a dumbed down system makes it easier to stay out of trouble, you only have the built-in "up elevator" so your opportunity to do something beyond your ability is limited. I get that.

But there's a few of us that would like to have something that would make ridge soaring fun again. The stuff we have now is adequate for those that only want to thermal and go XC, but on those blasting pre-frontal days all overcast it sure would be a blast ripping up and down the slopes, pulling up into nice round loops, barrel rolling and even four point axial rolls. You think buzzing the launch ramp is fun now, wait 'til you do it inverted. :shock:

All the while secured safely in your seat, a seat that converts from a casual posture for slow flight and extends for a really flat reclined posture for penetration.

And light stick forces, now there's a welcome idea.

I know that I tend to ramble, thanks for hangin' in there. Steve, dreaming of snap rolling and tail sliding with impunity. And vowing to never give in and just go dangle diving.
By Lazypilot
#402564
raquo wrote:
Wed Mar 07, 2018 2:36 am
Check out this Demoichelle aircraft with rigid wings with roll control by varying angle of incidence

https://newatlas.com/demoichelle-electr ... 0/#gallery

https://en.wikipedia.org/wiki/APEV_Scoutchel

It says the plans are available too, if you'd like for reference
I like that Demoichelle, Back in the 80's when powered ultralights were all the rage I wanted to make a modernized version of the original it just has a sassy look to it.

The "wingeron" idea is appealing to me, I want to achieve that without all the mechanical stuff, just warp the whole glider. Interesting that they use 4 degrees nose-up and 2 degrees nose down travel of the wings, just the opposite of the usual aileron differential. It would be nice to study their construction tech.

I was looking at a PSS (Power Scale Slope) model of a Mustang. And then I surfed over to the plans for a balsa sticks and formers version of a rubber powered Mustang. And I got to thinkin' why not just scale it up to my size? A Part 103 glider styled to resemble a P-51. I don't know why not. Carve it out of foam and reinforce with tubing, I got a bunch of glider frames lookin' for a new lease on life. A D-Day paint job of course, invasion stripes oh yeah! And as I understand it, 103 allows a stall speed of 27 mph. So on a pre-frontal day at Crestline I could launch it no sweat.

PSS models are rarely true scale, the Mustang has larger tail and wings for better performance. I'll bet it could be scaled up to full size and it would fly great. Have the landing wheel retract up into the belly scoop. It's possible. 8)
By Lazypilot
#402565
Paul H wrote:
Tue Mar 06, 2018 5:23 am
The VG on a modern glider isn't ridiculous at all if you stop thinking about it as just some kind of accelerator pedal for the wing. A very useful and often overlooked purpose for it is to use it as pitch trim just like in a powered aircraft. When you are thermaling you can set the VG to trim the glider to stay at the desired angle of bank with no bar pressure to work against. It's much more functional than some people realize. If you just leave it at one or two settings you will never get the best use from it. Also, the newer wings are very maneuverable with VG on.
I suppose the most useful thing the VG does is adjustable spiral stability. I've always considered variable dihedral a good idea. A foot operated one would be the way to go, I hate having to do it by hand, and my legs and feet oughta have to pay their way anyhow. With leg power we wouldn't need so much travel and it could be adjusted very quickly. Get your boy to put some pressure on Wills to make it happen. :)

"Also, the newer wings are very maneuverable with VG on." Your idea of "very maneuverable" is a long ways away from mine. But most are satisfied with just thermalling and XC. I'm not.
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By magentabluesky
#402589
Lazypilot wrote:In 1979 I almost bought the farm when I went too far with tensioning the lower deflexor cable on my Seagull 10 Meter.
Link

This reminded me of the Pulley System on the Wills Wing SST and the Alpha (first version). The Pulley System really did enhance Roll Control Augmentation. I had an Alpha 215 and only weighed 160lbs at the time and at that light wing loading the glider would turn with the Pulley System. I had a deflexor break on me, and let’s just say I flared in the turn, proving to me that without the pulley system at my weight, the glider was not controllable in roll.

A bow spirit glider would easily accommodate a nose pulley system to enhance Roll Control at the tips. Controlling the tips would have a much greater effect on controlling the glider in roll and yaw. The cable system could be connected to a hang strap system leaving the traditional triangle control bar intact.
A pulley or differential deflexor system is being used on a number of gliders. The way it works is this A continuous cable from one defexor through a pulley at the nose to the deflexor on the opposite side allows one leading edge to flex in at the tip while the opposite leading edge is pulled out. When a roll is started, the downward moving side flexes in, due to the increased pull on the sail, pulling the other side out and tightening the sail on that side. The result is an aerodynamic imbalance that works in the same way as billow shift to aid the roll rate. This is shown in figure 3a for a pulley system on the side deflexors.
How a Glider Really Turns – Part II Dennis Pagen Hang Gliding Magazine Dec 1978
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Pully System.JPG
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By magentabluesky
#402590
P.S. It would also be possible to have a Pulley/Deflexor System imbedded in a foam leading edge extending in front of the leading edge tube structure along with a floating cross bar. I would be like power steering.
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By lizzard
#402591
Over the years I have come to the conclusion that hang gliders and para gliders that rely on positive g for control are simply not safe to fly in thermic or rotor conditions above 12 knots .

Hang gliders are coastal machines ...that is not to say that there are some inland days that are just magic ..its just too hard for the average pilot to pick.

And there are a few who don't mind wire and sail slappers .

I'm of the mind that if think you need a chute WTF are you doing flying such a machine?
Big Air ? Killer Air !

So if we could have a controllable aircraft ...my horizion would return to foot launched inland flying in a heart beat.

For now when the coastal sites are on and un crowded ..i fly in peace and harmony in my basic yet comfortable dune harness with parachute rotting in with my heavy harness my garage.

I reiterate that we should just copy a bird skeleton and learn how to control it ..the design job is already done .
as long as there is enough give in the joints it would only need to be stressed to 3 g ...max

VG was is a step toward this ...just need a few more neoprene bushed hinges and lose the hang ,and control bar NO?
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By lizzard
#402594
Yes Some do ..many don't , I never wear use a chute with sailplanes.
Some of the top comp guys do though .
Inland flying for hang gliders, they are important ..that remains my point .
Ill spell it out
Hang gliders are smooth air machines and the very best at it bar none ..weight shift is perfect here and other than doing negative g aerobatics they are fine and evolved well.

BUT we can and should re design with the ability to recover from any situation (height allowing)

It about time we engaged flexible joints not just bending tubes for strength/load shedding.
Cantilever designs could be much lighter if we allowed for load shedding at the hinged points (think bird skeleton).


You know just like birds have done since before Adam,Allah, Buddha, etc.

This is an inspiring thread for the most part and in this age of delightnment and smart/dumb phones,apps instead of rewritten programs,etc etc,we all need a kick up the arse at times.
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By Paul H
#402610
lizzard wrote:
Thu Mar 08, 2018 7:44 pm
Over the years I have come to the conclusion that hang gliders and para gliders that rely on positive g for control are simply not safe to fly in thermic or rotor conditions above 12 knots .

Hang gliders are coastal machines ...that is not to say that there are some inland days that are just magic ..its just too hard for the average pilot to pick.

Wow! I wish someone had told me this much earlier. Since I began flying in 1991 I have done most of my flying in desert mountain thermals. Now that I know that it's simply not safe, I better knock it off and find something else to do.
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By lizzard
#402615
Perhaps un addressable risk would be a better term ...
Been at it since 74 from age 15 ...do the math I know what is out there .
Some old geezer telling me it is unsafe never stopped me ...no chutes then either

I would love to know your willy willy technique ?

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