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Painful Memories ... teaching still

Postby JoeF » Sat Apr 11, 2015 5:50 pm

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Re: Painful Memories ... teaching still

Postby JoeF » Sat Apr 11, 2015 6:07 pm

Unabridged by Eddie Paul
======================================== Re: 1970s pain and lessons ...

Forgot I wrote this a ways back and thought you might like it.


It would have killed a human…(sic)

I was hitting at least 120 mile per hour… in a vertical fall as that stomach-churning view of the ground was racing toward me at bone crushing speed. I was still over 300 feet from the ground and had just fallen out of my hang glider as the cross spar snapped at the point that I had earlier attached my harness. It was amazing to me that my mind was going faster than my air speed, as I was trying to come up with a way to hit the ground without splattering.

I vividly remembered a story that way told to me the week before of an unfortunate 17 year old hang glider pilot the had hit the ground in a crash from only 50 feet in the air. He was in an event when his wing tip broke off sending him in to a 50 foot dive to the ground, when he hit the ground he was thrown sideways and had passed through the 3/32 inch stainless steel side flying wires. He was busted up pretty good and lay on his face as a small crowd arrived to help him. The story went on, that as he was gently rolled on to his back his insides had poured out through the cable slice across his mid section. It was apparent to all, but him, that it would soon be over.

As he lay there, he asked his young wife how he was doing, his wife then responded with a straight face, “you’ll be fine”. He than closed his eyes and died.

That descriptive scene had stuck in my mind and all I could think of was how to hit the ground so I would not look bad to my Dad and wife somewhere down in the crowd of people below.

I knew in my gut that I should not have flown today, but was young and felt indestructible and was not about to cower down to a dare. It was a very windy Saturday in Torrance Beach Southern California. In fact it was one of the windiest days I have ever seen let alone flown in. I had just finished a new light-weight Hang glider design that I was about to test, and this seemed like a great day for a quick test in gusty conditions. Torrance Beach was a known site for hang gliding as it faced the west wind and had a 100 foot cliff that could be climbed from the south west side while carrying a glider.

I had arrive and drawn a small crowd with my new design as I laid my glider on the warm sands. My Porta-Wing was a unique design in hang gliding and was criticized by the competition mainly because it was lighter, easier to assemble, simpler, produced more lift, and sold for much less than theirs did.

But the biggest problem to them was it was in the process of being patented which meant they could not copy it. I was hated by most! So when I arrived the competitors had all come up to egg me on, encouraging me to fly. No one bothered to tell me of the 6 to 10 crashes that had occurred before I had arrived, I later found out that these were form gusty winds aloft.

I laid my “kite bag” on the sand and started pulling out the 4-foot tubes that set my design out from the others. Most hang gliders consist of 4 main tubes; a keel, a spar and two leading edge tubes which the sail is attached to. The Porta-Wing consisted of only two main tubes a keel and a cross spar, I then designed a perimeter cable which passed through my sail pocket acting as a leading edge support, and then it would attach to the tail making the whole structure a tensegrity design, one of the strongest geometric designs you could build with the least amount of material.

This allowed me to separate the main and spar tube into slip fit sections of four-foot lengths together, before assembly the glider was in a four foot bag and could be carried on a bike or in the trunk of a car. With only two tubes it was also very light, at about 20 pounds whereas most gliders are 60 to 120 pounds. All this created a strong competitive mood on the beach, which encouraged them to badger me into testing my new glider in the extreme winds of the day.

I was 18 years old and willing to try anything including flying in a storm to prove the design was sound. The glider was assembled without tools within 3 minutes, another big feature of the design and I was on my way up the hill.

After this flight I had plans to take my wife to a movie so one quick flight and we were off to the show, or so the plan was...

It took about five minutes to get to the top of Torrance hill where I waited my turn to launch. I was behind two other conventional Regallo style gliders as the first took off and was blown backwards over the hill into some power lines, the second went up like a rocket then nosed in.

Anybody in his or her right mind, would have packed it in at that point in time and faced the “name calling” at the bottom of the hill. But I decided I would give it a shot and see if I could do what no others could do that day.

As I stepped up to the edge of the cliff my sail caught some air and filled like it had never filled before, I was light on my feet and ready to lift off when the wind gusted and jerked me straight up.

It was like an elevator stuck in high speed, I was shooting toward the heavens like a rocket. I pulled myself forward as far as I could in an effort to tilt the nose of the glider down so I could slow my assent a bit, but there was no response, nothing. I pulled back as far as I could and even leaned forward in my swing seat harness, still nothing.

I was starting to get worried, the Porta-Wing was famous for being very sensitive on the controls, in fact, a one to two inch movement was all I ever needed to perform the most radical of maneuvers. I was still climbing faster than I thought possible which was stressing out the delicate tubing the glider was built from. I was in the fine line between being blown back over the hill into the dreaded power lines, or pulling the nose too far down and over stressing the main structure of the glider.

The people on the ground now looked like ants to me and the launch pad at the top of the cliff looked like a postage stamp. It was hard to believe it just held three fully assembled gliders, now it was becoming smaller with each passing second. The winds were still blowing at some 40 mph and gusting to 60 when suddenly the wind just stopped! Suddenly I was in the prone position pulled over the control bar further than I had ever been. This was an earlier attempt to bring the nose down and there was nothing I could do to get back in the seated position before the glider rotated into the vertical nose down position.

As the glider went vertical the wind suddenly picked up and was now blowing perpendicular to the top of the sail.

No hang glider is designed for this, the top of the glider has a king post with smaller diameter “non-flying” wires that are designed only to hold the structure while the glider is parked on the nose. It was not designed to hold the type of weight, which was now simulated by my current conditions.

Recovering from a vertical dive is impossible in any Regallo style glider, because they are only controlled by weight shift. This weight shift only works in a near-horizontal flying mode, not a falling nose down mode, so I rotated my position to put my feet on the control bar and shoved it out as fast and as far as I could. During this maneuver the wind again stopped for a brief second, and this allowed the glider to respond. As quickly as the glider dove it rotated through 180 degrees until it was now in the vertical position pointing straight up. The wind again gusted harder than ever and I heard the horrid snap that I anticipated, it was a sickening sound made as the one and one-half inch diameter 6061-T6 cross spar snapped at the center point, where the main keel, king post and control bar meet, it is also where I attach my swing seat which I was belted into.

The wind had taken me to about 360 feet above the ground and I was now free of my glider and free to come back to earth on my own. Not quite the way I would have chosen, but I was no longer at the mercy of the wind and it would soon be over.

Now keep in mind that 360 feet is about 36 stories, so next time you are in a large building go to the 36th floor and look out the window and you will have an idea how small things look from that altitude. As I left he glider I looked up, first in disbelief and saw the gliders broken remains about 20 feet above me suddenly stop its upward rotation and start to race me to earth.

I then quickly looked down and could see the specks on the sand that would soon be racing over to my broken and lifeless body.

Of all the thoughts that went through my mind, my main concern was for my family and how bad I was about the look to them. I was always told that if you land flat on your back you would absorb the impact throughout your body and survive a long fall, but I wasn’t buying it. It never made any sense to me, if your head hits the ground at 120 miles per hour, you are dead!

I have always felt that if you fall feet first and absorb the impact from your feet up you might live. Sure you feet and legs would be shattered but you head would live and in time your legs would heal or not.

Of course this would work in a short fall, not 360 feet. But it would look better to have broken leg bones than hitting face first.

So I rotated into the feet first position and looked down to my landing site. A new problem was below me, it was the brand new fence that the neighbors had built to keep hang gliders off their property. It was directly below me and was about to cut me in half if I didn’t do something, but what?

I was no longer in control of my landing area only God was, So I said a quick prayer and as I did the wind gave a me a shove and pushed me back about four feet, just enough to clear the fence and keep the crowd away from my body when I hit.

My thoughts were only of my soon to be untimely demise, as there was no way in the world I was going to survive this one. I was about 3 seconds from impact and time was starting to slow down for me, I was trying to spot my wife and dad as I fell, to no avail, they were somewhere in the mass of the hundreds below.

I don’t remember the impact or any pain, even though I later found out that the sound of breaking bones could be heard by all below.

I laid there on my back as the glider came down on top of me and so I was covered by the Porta-Wing wreckage, until my dad jumped the 8 foot chain link fence to get to me.

He pulled the gliders sail off me and found me not only awake but alert and talking. I was in no pain at all, and was a little embarrassed at the crowd I had drawn, and even said, “ I’m sure you are all wondering why I called you together…” which drew mixed reactions.

I told my Dad I was OK and was going to get up now. But everyone yelled to stay down and wait for the paramedics.

This was another lucky event, or was it God again? It seemed that the day I was flying some surfers were taking advantage of the wind fed waves and showing off a bit in the sea off of Torrance beach. And a “surfer turned paramedic” on a lunch break stopped at the parking lot to watch his buddies in the water.

He was driving the rescue vehicle when the downed pilot call came in, his ETA was about 30 seconds. Any longer and I would have died from shock, but as the day’s events unrolled it was becoming very apparent, it was not my time. Did God have other plans for me? Why was I still alive, I wondered?

Everybody that witnessed the event said there was no doubt at all that I was dead, at one point, I even looked up at my dad and asked, “How bad is it?” “That fall would have killed a human” my Dad said, in response to my question.

But still I was not only alive but felt fine! I thought I could get up and go to the movies now, but later found out otherwise.

Three possibilities were racing through my head as I lay there: One was that I was dead and this is what it would be like, no pain and you just go on as if you made it.

Or two, I was not dead or hurt and this was a bad dream.

But option Three and my favorite was that I did get hurt real bad, and the pain was yet to come.

The property owner had now joined the crowd that was around me and was telling the Paramedics that they should pass me over the newly installed fence to save him the cost of replacing it. “After all he is going to die soon from the fall, if he isn’t dead now!” he stated, to the sound of snapping steel, as one of the paramedics proceeded to cut a larger than needed hole in the shiny new fence in order to get me out.

I was taken out and up the hill to the awaiting ambulance with my wife and Dad in tow as a close friend decided to stay behind and dig my glider out of the dirt. Did I mention that when I missed the fence I also missed the ocean and the sand and managed to find the hardest part of the beach and that is where I landed, not that it would matter.

At 120 miles per hour water would feel like concrete anyway so it really didn’t matter.

I remember every element of the event in the most minute detail. I remember the paramedics name was Powers, as it was engraved on his badge, and he told me of an invention he was working on. Which I found out latter was a success and sold all over the world, it was called the Burn Pack.

I was alert and talkative, which amazed them, and I never moaned or complained once. I think I was talking and listening intently to keep my mind off the impending pain. We arrived and the first Hospital and I was wheeled into intensive care for admittance. As a Doctor came over and asked a few questions of the Paramedics, a quick conversation ensued and I overheard the Doctor make the statement that I was going to die and I had no insurance and who would pay the bill?

Powers raised his voice at this point and said to his partner and my dad, “we are going to take him to a real Hospital”. They loaded me up and off we went, oddly I still felt fine and was alert. About 20 minutes later we arrived at Harbor General Hospital and I was again unloaded and wheel into Emergency, but this time was different, The was no questions about payment but there was a vital rush to get me into X-Ray.

As I was being rolled in to X-Ray I remember telling my wife “Don’t worry, I feel fine they are going to grab a few photos and I will be out of here before the show starts.”

As I was entering the X-Ray room things got a little dark and I couldn’t figure out how they knew where to go in the dark. So I closed my eyes…but only for a second.

Two weeks later….I slowly opened my eyes and found I was flat on my back in unfamiliar surroundings, so I was careful not to move until I figured out what was going on. I kind of remember falling out of the sky, and hitting something and being rushed to the Hospital but from there on it was fuzzy. I slowly tried moving my legs or was I? I have heard with phantom limbs, you could swear you have legs and feet and find out you don’t, so without looking I had no idea. I didn’t want to look, not quite yet anyway.

I don’t think I could take it yet. I tried my right hand and it seemed to work so I lifted it to my face and saw my hand. Not bad my hand was still there, but boy did I hurt… everything was in pain, my whole body ached, so I fell back to sleep for awhile.

When I awoke I did some more exploratory work, I used my left hand this time after checking to see if I had one. I slowly ran my hand down my side and felt my upper leg, so far so good.

I then felt for my face, which also hurt. And suddenly felt some type of rod or pipe, was it a piece of the fence? Why was in the bed with me? Where is it sticking into or out of? This sent me into all types of thoughts, none were good, as my hand slowly followed the tube or pipe away from my body I found it was very long, in fact I could not reach the end of it.

So I then followed it toward me, to see where it was impaled. As my hand slowly followed it toward my face it ended at my nose. How in the heck did I jab a pipe up my nose? And how far was it in? Obviously so far that they could not get it out…. I again passed out at the thought.

Later I came to again, and once again explored the baffling pipe only to find it was not a pipe at all but a bright red tube? It was all starting to come together, it was in my nose to pump blood in or out of me… If it is out of me then I am I bad shape, if it is into to me then I was also in bad shape, either way It was too much to deal with right now, and I again passed out.

This time when I awoke it was to the voice of my Dad and Wife (Kris) asking how I felt. My first question was could I have water and what day is it? To the second I was told it was two weeks since the accident, and no! I could not have water, at least not yet.

I was told that the doctors had been waiting for my blood pressure to raise enough to operate on me, and due to the pending operation I could not have water.

I was in and out of consciousness dozens of times an hour and each time would ask the same questions to get the same answer to which I would agree and then pass out again. I was later moved from intensive care to the ward where my chances of living were assumed fair, and my chance of walking dim to none.

It appeared that in the fall which landed me feet first (yea!) I broke my pelvis in over 30 places and ruptured my stomach, spleen, liver, diaphragm, and a few other organs in the process. The falling glider hit me in the head giving me a concussion also. While I was out, my blood pressure was too low to operate on me, and my dad or Kris would not give permission without my consent anyway, Then once I came too, my blood pressure rose because the internal bleeding stopped, so there was no reason to cut.

The “operation” I was later told, was exploratory, and may well have killed me with all the internal damage I had.

So, in hindsight I was again much more that just lucky.

I was now in the ward laughing and joking with my five roommates about a month after the crash.

Then… one day I felt a pain in my chest when I took a breath, at first it just felt uncomfortable but got slowly worse. At about 3AM in the morning I woke to what felt like an encounter with OJ Simpson, I could swear I had been stabbed with a large knife in the back. I could not move at all, I could only open my eyes and hope someone ion my ward would be awake and help.

My thought was that on top of everything else, was I now having a heart attack? I could see the emergency button hanging over my chest just inches from my right hand, but I could not move my hand to grab it, not the three inches I needed to get a Doctor in to help me, it was the most helpless feeling in the world. I knew that I could die three inches from help.

Again… a miracle happened, and the guy across the ward could not sleep, and saw the distress in my eyes and buzzed the Nurse for me.

The pain was beyond anything I had ever felt in my life, it was not just the stabbing but with each breath it felt like the large knife was twisted. The night crew showed up with the “crash cart” just in case it was a heart attack.

A doctor came in shortly after the Nurses and examined me, and as if my hearing was impaired or I was just stupid, told the Nurses, that his bet was “I would not make it through the night.”

What in the hell kind of bedside manor was this? the nerve of this pompous jerk! Doesn’t he know that even though I can’t move, I can still hear!

This statement scared me so bad it may have inadvertently saved my life. I was going to show him! I was not going to give in or quit no matter how bad the pain, I would no pass out and I would concentrate on each breath no matter how much it hurts. And boy did it hurt! Each breath was harder than anything I had ever done in my life, I found that slow shallow breaths would keep me from passing out, and a deep breath would knock me out, only to be awakened by the pain of the next breath.

This lasted some two to three weeks and of course sent me into intensive care again, totally paralyzed but able to communicate by blinking, one blink was for yes, and two for no, and once again, no water.

I later found out that what I had experienced was a pulmonary embolism or in layman’s terms, a blood clot in one of my lungs, a result of a major blood clot from all the internal bleeding I had done earlier.

One terrifying moment happened while I was in ICU and as I was laying on my back with my head rolled to the left.

My field of view was limited to a monitor of the guy across from me who was in real bad shape, I never saw him move the whole time I was there. Anyway all I could see was his heart beat on the screen and as I was concentrating on it to keep my mind off my pain caused by each breath I took I saw that his heart beat suddenly stopped!

He flat-lined and I could not yell for help. I wanted so much to return the favor that my roommate extended to me and I could not!

This was the sickest feeling, he would die and I couldn’t lift a finger to help him. Just as I was starting to choke up in desperation, a Nurse walked over and reconnected his sensor and his heartbeat returned!

He was still alive, there was nothing wrong…he would live. I felt better. Six months later I was out of the hospital, a year later was walking and back to work, not as a hang glider manufacture but something much safer, after all I am not stupid, besides a stunt man for the studios pays better… and has Great insurance.

Eddie Paul
President and CEO

"Technology Rapidly brought to Reality"

E. P. Industries, Inc.
Since 1968
414 west Walnut ave.
El Segundo CA 90245
phone 310-322-8035
Cell 310-259-0542
fax 310-322-8044
eddiepaul@epindustries.com
web sites
epindustries.com
deadlinetv.net
Listen to my Radio shows at:
http://eddiepaulstooltalk.wix.com/eddiepaulstooltalk
Also visit EddiePaulHowToUniversity.com
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Re: Painful Memories ... teaching still

Postby Rick Masters » Sat Apr 11, 2015 6:34 pm

Image

Image

Just imagine! Eddie Paul discovered why tubing leading edges were important back in 1973, but today's soaring parachutists are still trying to figure it out!

Image

$395 - cheap! The money you saved on tubing went towards your hospital bills. :srofl:

Image

Porta-Wing pilots discuss technique.
"And there I was... I said to myself, I'm about to die!"
"Hey, me too!"
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Re: Painful Memories ... teaching still

Postby Bob Kuczewski » Sat Apr 11, 2015 9:44 pm

That is an amazing story Joe. I've heard the name "Eddie Paul" before, but this story gives me a perspective that I don't think I could ever get without reading his own words.

Thanks very very much for the post.

Thanks also Rick for adding the pictures.

It's really an amazing fortune to have you both posting your lifetime of experiences here on the US Hawks. That's yet another example of where USHPA has totally missed the boat. They're so desperate to wrap their arms around the paragliding community that they've really ignored the treasures we have in our sport.

Once again, USHPA's stupidity is the US Hawks' gain.
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Re: Painful Memories ... teaching still

Postby JoeF » Sun Apr 12, 2015 9:55 am

Your sharing is important, Eddie.
Rick has been leader in chronicling the impact of negative-G in canopy soaring parachutes (paragliders, PGs). He is not showing generally as a hater, but as a mechanical analyst of what occurs when negative-g forces occur in turbulence on airframed and canopy-only aircraft. He has facts on 1, 304 deaths since 2002 in the soaring parachutes; non-death injury rate is also studied by him for the soaring high-aspect-ratio canopies. Even in mild winds, the naturally occurring gusts that give neg-g has collapsed wings falling nearly as rocks; the soaring-canopy makers cannot design such out without going to positive-inflation and/or airframes; the long hang string affair complicates the challenges. Your sharing of a hybrid craft to the world provides yet a craft for important study with regard to airframe matters and the potential to handle and penetrate past such turbulence. The studies are still not sufficiently comprehensive to define the family of cable-leading edge flexwings. Your investments and costs have been considerable indeed. Surely the costs are still with you!
Ever wishing you and yours the best,
Joe
CC: Rick Masters
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Re: Painful Memories ... teaching still

Postby Rick Masters » Sun Apr 12, 2015 1:13 pm

He is not showing generally as a hater


Actually, I do hate to see so many people die on paragliders. It is my primary motivation on being outspoken.
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Re: Painful Memories ... teaching still

Postby JoeF » Sun Apr 12, 2015 2:35 pm

RM, accepted!
===========================
Please see attached PDF bio on Eddie Paul
EPbio.pdf
(187.93 KiB) Downloaded 420 times

===
Eddie Paul noted in 2015
today:
Joe,
As you know, the cable leading edge had nothing to do with the crash, it was the high winds and wind gust that caused the crash as it had with the other “standard” gliders that day; where the glider broke was where any glider would have broke if the same load situation were applied, but the problem is that many narrow-minded people hate anything that was or is different, such as cable leading edges and this will never change, to the point that they had to even make up many false accident reports at USHGA about how many people died on my glider; I think I had more deaths attributed to my glider than gliders we had ever sold. (bad memories). When they in fact were dropping out of the skies on most of the other brands by the handful. You have the records.

So cartoons (like the one posted in the forum right behind my story) are posted about the Porta-Wing and never seem to go away.
This is the main reason I got out of the business of designing Hang gliders, not the crash. It was the “haters” and the narrow-minded people that we attracted to the sport; and I am afraid that this will never change; I think I could have added a lot to the sport, but I was out numbered by the many.

This is not aimed at you Joe, as I consider you a friend, but this sport has attracted a lot of people that I do not want to be around. They criticize instead of contribute, yell rather than speak, and hate rather than help. Since I left the sport I have done well, feel better, and added a lot to other areas of life and sports; and it feels good to contribute to a cause that appreciates the small contribution I have made. (see attached). So in light of this recent post I don’t believe I will attend the meeting at the beach, as it would only stir up more controversy. And bring back more bad memories, memories that I have spent years trying to forget. That one cartoon brought it all back.

[Addendum note, this paragraph:] Well, adding that cartoon was way out of line, as a conversation [there] would have been a better way to handle it. I have never been an advocate of the hang glider as a form of flight as with weight shift you are restricted on control. The ultra lights are better as they have control surfaces, but that is a another subject. The cartoon is just beating a dead horse, as I am not getting back into the business so they do not have to worry.

Eddie Paul
President and CEO

"Technology Rapidly brought to Reality"

E. P. Industries, Inc.
Since 1968
414 west Walnut ave.
El Segundo CA 90245
==============================================[[ Eddie's creative habit is shown in this matter just shared: ]]

If there was a problem with leading edge collapsing downward… (which I still do not believe, this would have been a simple, lightweight fix to hold the leading edge shape). This only took me about 5 minutes to come up with, I assume no one else has come up with a fix yet?
LeadingEdgeShaperEPonPortaWingMOD2015.jpg
LeadingEdgeShaperEPonPortaWingMOD2015.jpg (106.68 KiB) Viewed 6481 times

LeadingEdgeShaperEPIndustriesPortaWingMOD2015b.jpg
LeadingEdgeShaperEPIndustriesPortaWingMOD2015b.jpg (49.11 KiB) Viewed 6481 times

lertsidesailremovedtoshowcables.jpg
lertsidesailremovedtoshowcables.jpg (58.75 KiB) Viewed 6481 times

leadingedgeshaper1.jpg
leadingedgeshaper1.jpg (67.88 KiB) Viewed 6481 times

leadingedgeshaper2.jpg
leadingedgeshaper2.jpg (83.22 KiB) Viewed 6481 times

leadingedgeshaper3.jpg
leadingedgeshaper3.jpg (94.5 KiB) Viewed 6481 times
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Re: Painful Memories ... teaching still

Postby Rick Masters » Sun Apr 12, 2015 4:16 pm

...the cable leading edge had nothing to do with the crash...


Some of us with engineering experience may wish to point out that a cable leading edge, when severely stressed by positive load, develops an arc. This causes the crossbar ends to move forward, placing the crossbar out of column. Out-of-column tubing will fail below design strength. This is the primary reason cable leading edges were abandoned and never played a meaningful role in the evolution of hang gliding. Engineering analysis has nothing to do with designers, cartoons or pique. It simply provides a mathematical red flag where needed.
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Re: Painful Memories ... teaching still

Postby JoeF » Mon Apr 13, 2015 1:09 pm

Some points from two correspondents regarding the beam:

Pere Casellas: "
Pere Casellas wrote:Just add that Bob Rouse, found a solution to the cross bar very compressed. Using deflectors and cables, to make more rigid cross bar, and avoid the effect of buckling.

Best regards,
Pere"


==============
Eddie Paul:
RM noted:“Some of us with engineering experience...”

Eddie replies: Maybe with his expert eye as a top engineer he did not notice the tension cable (or perimeter cable) that I had in the drawing to eleviate the bending stress he refers to, My God I even made it yellow so it could easily be spotted in the illustration... but then I don’t have any engineering experience, so what do I know... I can see this whole exercise is a waste of time, I probably have built more in a few weeks than he has in his whole life (but I do not know him, so I cannot assume that he is not one of the top engineers in the entire world). Also I do not have any engineering experience... so cannot judge.
Love to wax on but believe it or not I have an air-powered sub to design and build to Discovery, so got to go.
================================================================================================
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Re: Painful Memories ... teaching still

Postby Rick Masters » Mon Apr 13, 2015 2:28 pm

Years after the Whitney Port-a-Wing, the divergence problem was resolved when each hang glider manufacturer was required to dynamically test their product at specific angles of attack and velocity to achieve HGMA certification (adopted from the German testing procedures). This was usually done by mounting the glider to a vehicle and filming the test. The primary purpose of the test was to
1) demonstrate that the glider would not fail under a designated negative load and
2) would generate enough positive pitch, through sail design, reflex and/or luff lines, to recover from a dive.

The tests did not require engineering credentials on anyone's part. It was simple. It was brilliant. It saved a lot of lives.

These tests were scarey to film. The gliders would be mounted high up on the test vehicle, nose first, nose down, then, for the second test, tail first, tail down, and driven up to a speed of 60 mph or so. Approaching top speed was stressful, not just to the aircraft, but to the designer/builders. Failure often came suddenly - in defiance of all calculations or predictions. After the explosive collapse and flailing tubing, the airframe would need to be strengthened and retested until it held up.

To my knowledge, no cable leading edge hang glider ever passed this test.

Image

The first backpackable hang glider to pass this test was the German Finsterwalder Bergfex in 1977. Over 300 Bergfex rogallos were flown without a single structural failure. This testing protocol, universally implemented, transformed hang gliding from a reckless risk-taker sport to a genuine aviation enthusiast sport.

The requirement of testing hang gliders represents the USHGA's finest hour. They made the difficult decision to force hang glider manufacturers to prove the robustness of their products for the safety of the USHGA membership - and the manufacturers, admirably, proceeded to eliminate, in short order, the divergence issues that had plagued the sport. Unfortunately, the USHGA shamefully threw away their safety obligations to membership by accepting soaring parachutes in the late 1980s. While it took only a couple of years to solve the divergence problem in hang gliders, once the testing program got started, the comparable testing of paragliders has not yet prevented their collapse in turbulence after more than 30 years.

It is incredible to me that soaring parachutists disregard this. Also unbelievable is that the bastard of the USHGA, the USHPA, and the other bastardized organizations worldwide actively accept paragliding testing as legitimate in the very face of the continuing global death counts from collapse.
Rick Masters
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