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Trike general instability warning


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Hi all,

 

I dont post much any where these years but some things are important as our declining numbers reduce information sharing.

 

Any way , Im from the early trike days when soarmasters were the rage ,I had the only one in oz for a few years and soon learned that my home built trike with a yamaha 350cc direct drive flew so much better than the soarmaster ..obvious today of course.

 

Over the years as 2 place trikes with 447 503 532 and hanglider wings with some strength added in a few areas, keel, wires and sometimes cross bars . no real engineering but hang gliders were designed by built it until it breaks then fix that bit (  general aviation does this too if you look at the history)

These slower machines which were protected by the billow , load shedding and air speed limits of about 40mph there were few structural problems and no spiral dives  back then.

 

As some of us started to re invent the aircraft and train pilots to understand that other air users were to be allowed for ,the speeds and stiffness of our modified hang gliders was having the effect of High landing speeds and enough inertia to loop if that was how silly you wanted to be .

 

The one thing that I noticed with these new fast strong hang gliders was that when flying 2 up one could stall in a tight turn and have the bar forced away from you with high force and build speed with no real control .

 

I experienced this once at 2000 ft and somehow pulled out at 500 ft .

 

The problem in a nutshell is that when a well loaded weight shift aircraft  stalls at high speed causes the g loading to increase making it even more impossible to recover .

 

Many wind in spiral dive deaths  were caused by this . Few were ever defined as speed stall spiral dives.

 

A low weight converted hang glider will not suffer from this defect which was never discussed by manufacturers who would say ,rightfully ,dont stall at high bank and introduce training to avoid the condition in the first place . This was the only sensible thing to do at the time but never admitting that weight shift aircraft have limits as all aircraft do .

 

As my age and wisdom combine I find myself flying my nano trike , an airborne shark  or a fun 190 over a m25y black devil  ,to be the most satisfying thing to fly just as they were in the late 70's  but much better power plants and props  .

 

Strictly coastal flying avoids power lines and offers safe landing 99% of the time .

This is to me what ultralight flying is all about ,there is no where to go so and lots to see ...what's  the $$%ing hurry any way ?

20 paces take off  30 paces landing ...less with wind . and 10 liters of fuel is a days flying ..assisted by cliffs and sand dunes .

They are pretty shitty to fly in mid day thermals unless that's your thing ..its not mine .

 

Any  way I hope that this message is well received by those who have as did I , out smarted myself with the latest and greatest only to discover that cabin heat and comfort is available at airports  and ultralights were invented because of their simplicity portability and forgiving handling (as long as the weight is kept down).

 

This is all just my opinion based on lots of trials and few errors.

 

Safe Flying, however you make it so .

 

 

 

 

 

 

 

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Back in the late 70s/early 80s manufacturers began adding luff lines from the king post to the trailing edge of the inner battens and adding a dive tube at the wingtip that would prevent the tip inverting. These mods were to prevent the sail inverting or luffing after a major stall at altitude so the wing would pull out of the dive. before this the glider could just descend vertically with the sail luffing until it hit the ground.

 

We were in our 20s then and bullet proof. After returning from the NZ national champs at Coronet peak near Queenstown where I'd got right in to 120 deg wingovers, I ended up stalling at the top of a more than 120 deg wingover and the wing ended upside down with me crashing in to the hang point (CG). I was still hanging on to the A frame base, got my feet out of the harness & stood on the cross bar. The glider spun upside down & then flipped over & I landed. It all happened in a few seconds but felt like eternity. The funny thing was that it didn't bother me at the time. It was only later that I started shaking and getting everything muddled realising I'd had the shit scared out of me. I never did another wingover again ever.

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Yep Them were the days alright !

when luff lines became the norm some of us speculated that they enhanced the tumble effect ..we were all amateur aeronautical engineers /test pilots . So we thought .

We were right in hindsight.

 

Steve Cohen , the maker of the best dune/coast glider that I know of once had and accident exactly like yours except he went all the way to ground . It was at stanwell late 70's I think.


 

 

Trikes can be flown safely in some very nasty air but they are simply not pleasurable and fixed wing gliders are the most fit for purpose in rowdy air.

 

 

Now days we see lots of para gliders filling this genre which we and all pilots KNOW are not safe in turbulence ,even wake turbulence . Yet the portability and easy landings seem to be enough for this generation to accept the risk ...oh that's right they all carry chutes so no problem..?

 

I wonder if I was 17 today if I would be a bag flyer . They are easier to teach hard to launch but easy to land.

 

Here is a shot from a few days ago at shelley beach WA you may be able to see the scratching jellyfish on th ridge.

 

Oh and to the photo addicts out there ...get a canon R5 .. It is an absolute game changer . Expensive but you only need cheap zoom lens as the electronic compensation actually works .  I used to take 4 shots and usually get 1 keeper ...now I struggle to find rejects.

The back view finder can be moved about enabling you to reach out with the camera and clear  wings and wires and the ocasional foot.

 

Th one with both feet is a full res jpeg  just in case you want to pixel peep.

_J5A1478.thumb.JPG.2008897058d2290fabf92c27071d0edf.JPG

_J5A1485.JPG

IMG_0732.JPG

Edited by Lizzard
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Mine was in a Skytrek Bandit 30%er a beautifully balanced glider with light controls. My previous glider was one of Steve Cohens which was also a great handling Glider called a Chevron purchased in June 78. it had a V keel instead of luff lines and no blowdowns.

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Wow similar history .

Here is my List

Wind soarer mk2 by jay Mc Farlane in wa.

No battens but the latest and safest due to the 1.5 inches of keel reflex to prevent luff dives (yeah right)

Wings condor floaty slugish but High tech conduit battens and reflex in the keel

Wings kestrel sloppy but lots of long soaring flights around cairns  and rainbow beach.

Twister 5 ...nothing good to say about this one . deflexors  heavy ,good LD for its time but who needs LD on coastal

Skydart 2 a well balanced lightweight quick setup ..still love it in my mind . a bit small for the soarmaster

Chevron 190 a floaty version of the skydart  with balanced deflexors and good for the soarmaster and my first trike .

 

 

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My first was a Seagull 3 an original battenless full Rogallo wing early 76. Terrible L/D but easy to fly. This is what I learned to fly in. There were no instructors or schools. It was just have a go. I bent it several times but not myself luckily.

 

Next came a Lancer 1, made by Pacific Kites in Auckland NZ, smaller wing higher aspect ratio fully battened single surface. Flew well but did not have a great reputation, mainly I think because some who bought them never adjusted to the different characteristics of a higher performance wing.

 

Next the Chevron followed by the Skytrek Bandit 30%er. Broke my radius & crushed the wrist in the NZ Nationals at Coronet Peak in December 1980. At the time I was President on the NZHGA & there was a TV crew in the landing paddock following me in. A dust devil caught me under the RH wing at about 30 feet & flying slow to get to the bulls eye & I went in hitting the ground with the nose & LH upright at the same time. It was on the news that night but I never got to see it.

 

Next and last was a Vampyre full aerofoil with floating crossbar & variable geometry nose angle. I sold it in 1990. We started flat land towing behind cars but I never got away in any thermals from towing. I flew a few home built trikes an Easy Riser Bi-plane and a mates Fledge plus lots of other gliders when I'd swap with friends.

 

In the mid to late 80s I flew a few rag & tube microlights including a very early weight shift Quicksilver. By then though I'd got my PPL so drifted away from the seat of the pants flying to eventually building my Morgan Sierra starting in 2011 with first flight in 2015 & still going with it. I doubt that I will ever own another aircraft given I will be 74 in a week or so but I'll keep flying the Sierra till something warns me it is time to fold my wings for good. Hopefully that will happen when I am on the ground.

 

 

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14 hours ago, Lizzard said:

Yep Them were the days alright !

when luff lines became the norm some of us speculated that they enhanced the tumble effect ..we were all amateur aeronautical engineers /test pilots . So we thought .

We were right in hindsight.

 

Steve Cohen , the maker of the best dune/coast glider that I know of once had and accident exactly like yours except he went all the way to ground . It was at stanwell late 70's I think.


 

 

Trikes can be flown safely in some very nasty air but they are simply not pleasurable and fixed wing gliders are the most fit for purpose in rowdy air.

 

 

Now days we see lots of para gliders filling this genre which we and all pilots KNOW are not safe in turbulence ,even wake turbulence . Yet the portability and easy landings seem to be enough for this generation to accept the risk ...oh that's right they all carry chutes so no problem..?

 

I wonder if I was 17 today if I would be a bag flyer . They are easier to teach hard to launch but easy to land.

 

Here is a shot from a few days ago at shelley beach WA you may be able to see the scratching jellyfish on th ridge.

 

Oh and to the photo addicts out there ...get a canon R5 .. It is an absolute game changer . Expensive but you only need cheap zoom lens as the electronic compensation actually works .  I used to take 4 shots and usually get 1 keeper ...now I struggle to find rejects.

The back view finder can be moved about enabling you to reach out with the camera and clear  wings and wires and the ocasional foot.

 

Th one with both feet is a full res jpeg  just in case you want to pixel peep.

_J5A1478.thumb.JPG.2008897058d2290fabf92c27071d0edf.JPG

_J5A1485.JPG

IMG_0732.JPG

That photo of Shelley's makes me home sick.   Beautiful coast along there.

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