Flying Dragon Wings in REVERSE!

[gyropilot]

You read the title of this thread correctly!

I conducted a little experiment today which resulted in some amazing results. Here's what happened...

As I was preflighting my GyroBee early this morning, there was a slight breeze blowing. I had the Dragon Wing rotor blades untied for cleaning and when I would let go of them for a few moments, they would gradually begin to rotate backwards. The speed would slowly build until I'd grab them. As soon as I would let go again, the process would repeat.

I couldn't help but ponder why these blades seemed so eager to rotate backwards, but an interesting experiment popped into my head: What if I were to prerotate the blades backwards and fly with them that way? I figured it couldn't hurt to try... right? Surely no one else has ever tried this!

I quickly finished my preflight, positioned the gyro into the breeze, patted up the blades (in reverse) as quickly as I could, fired up the engine, strapped in, and taxied out for takeoff. I was amazed by how fast the blades came up to speed while taxiing.

As soon as I reached the runway and started the takeoff roll, I knew I was in for something special... the nose came up early and once the gyro broke ground, it *shot* skyward like it had rocket assist! With the blades rotating in reverse, that sharp leading edge must result in very low drag. Blade speed was much lower than normal. Usually it's about 330 to 345 rpm, but today it was only 200!

The best part was the cruise engine speed 500 rpm less and as a result, fuel consumption was way down. I flew 2.2 hours, 92.9 miles on only 6.2 gallons of fuel. Awesome!

Now I knew there would be skeptics, so while I was up cruising around, I took a short movie of the blades rotating backwards as proof. The link below is for a 1.5 meg .AVI file that you can download and play on any MS Windows machine. I haven't edited or altered the footage in any way.

When you view the movie, you'll notice how I briefly swung the camera over to the horizon to show you I was actually flying, because I figured someone would accuse me of taking the movie while sitting on the ground.

Those of you with really slow connections might want to skip this.

Dragon Wings Rotating in Reverse (http://home.usaa.net/~gyropilot001/Flying/GyroBee.AVI)

Has anyone else had any success using gyroplane rotor blades in reverse?

Regards,

John L.

[CLS447]

No Way !!!!!!

[Mike Hook]

Seems like you have broken all the rules and made some new ones. This ought to bring on the comments. Maybe a advancement in rotorcraft. Seems like we hear all the time how draggy the rotor is.

Great going, keep us posted on any futher tests.


Mike

[Udi]

RFLMAO!!! :D

John - that's impossible - a sunny day in Washington???

:cool:
p.s. which program did you use to do that?

[Mike Hook]

Something just struck me on your comments, if your rotor is operating at 200 RPM then you will be able to fly faster with out rotor stall. At least that is what I gather from the input here on the forum.

Mike

[RHerron]

John,

Interestingly, I just recently had a heated debate with an old fellow that had convinced himself that gyro blades would do better turning backwards and that the gyro community was mistaken on the concept of autorotation.
I assured him that it wouldn't be possible. ..too many smart folks.
Now you've done it John ("throbbing member")!
I think someone has "hacked" the conference.

[joeheli]

"Ladies and genterman , WE FOUND THE NEW IGOR BENSEN THE II "
just a small joke ! :D . As a friend:Try not to do experiment with you and your gyro on the air ,it coud cost you your LIFE!!! That is why we pay
the govement, so they can do experiment. WITH A DUMMY!

[WN]

And I suppose Ron Awad was flying beside you - Inverted! I don't buy it John. :D

[scott heger]

Wow,......you sure the camera was not running in reverse....LOL. My only question would be with the strength of the blades. I dont think the trailing edge (now the leading edge), is made to be as strong and resistant to flexing or a minor strike(like a bird). But have to admire your guts in doing this test John. You win the worldwide gyro flight of the week (or con artist)award!!!

Scott Heger, Laguna Niguel, Ca SportCopter N86SH

[MattPearson]

How was the stick shake? :)

[mceagle]

Sorry, I do not buy it.
The C of G would be at the 75% position which would cause uncontrolable and destructive flutter.
Makes an interesting story though. I hope no one else tries it.

[birdy]

Hmmmmm...............I'v had me rotors start to rotate backwards in a wind on the ground too,but I am content to fly them going forwards.

[birdy]

Yes,I'm a sceptic,I'v also seen my blades rotating backwards on video too,same as wagon wheels goi'n backwards in the old movies.
I'm also a strong beliver that,nothing is imposible.

[ToddP]

Hmmm, Lets see, April Fools was a few weeks ago. Could it be, could it really work. My skepticism comes from the fact that I've read John's gyro progression from the beginning. He's not the kind of person that says, wow this is cool, I think I'll just take off and see if this works. But maybe there's a little daredevil there I didn't know about. :eek:

[C. Beaty]

Great experiment, John.

Here’s how to put the finishing touches on it.

Port scavenged 2-stroke engines don’t much care which way they run.

Flip the recoil starter over, retime the mag and you can back all the way around the pattern. Yaw control might be a little tricky but I’m sure you can manage it.

[Mike Jackson]

I guess Jay Carter can quit! His investers will be pissed. You've obviously greatly exceeded his Mu > 1 goal. The Army will soon be knocking down your door. You're now a rich man!!

Mike

[mceagle]

Re Chucks comment - Then it would be a tractor Gyro - ie you could use the same gyro as a tractor or pusher - twice as much fun.

[Aussie_Paul]

Ken J has to be in here somewhere as well!!!!! Aussie Paul.

[GyroRon]

Here I am John took this pic but forgot to post it too. Glad I installed that inverted fuel system last week.

[GeneWeber]

Wow John,

This is just unbelievable. It’s amazing that no one has tried this before. I ran Javafoil simulations of an NACA2311 airfoil, then I created coordinates for the same airfoil in reverse (pointed leading edge, blunt trailing edge) and re-ran simulations. Here are the polar results. As you can see not only is the lift improved, but the drag is decreased just as you’re saying. Looks like the world of aerodynamics will be turned upside down.

http://www.rotaryforum.com/forum/attachment.php?attachmentid=1573&stc=1

Regards,

Gene

BTW: .prac pu edam fo hcnub a si ffuts drawkcab sihT

[rehler]

Gene,

I have to admit, at first I didn't believe, but graphs don't lie. It must be true.

My new engine turns the opposite direction from my old engine. I was going to buy a new prop, but now I'll just use my old one and let it turn backward. That should work - maybe better!

Thanks.

[quadrirotor]

you are the best!

[Screw]

Screw-In

Did you start the day with a "McGriddle and a Dr. Pepper?"

Screw-Out

[C. Beaty]

Gene,

I have to admit, at first I didn't believe, but graphs don't lie. It must be true.

My new engine turns the opposite direction from my old engine. I was going to buy a new prop, but now I'll just use my old one and let it turn backward. That should work - maybe better!

Thanks.

Strange as it may seen, that's been done, Ken. A friend of mine installed the wooden prop on his Mac backwards.

Doesn't change the direction of push but the trailing edge becomes the leading edge.

It exploded just as he lifted off; sounded like someone fired both barrels of a 12 guage shotgun.

[GyroRon]

John I have since moved onto Honey Nut Cherrios and a snickers bar before inverted flight. But thinking I might do better next time if I wait till lunch time and have a Wendys spicy chicken combo.... Biggie sized of course!

[gyropilot]

A friend of mine installed the wooden prop on his Mac backwards.

Doesn't change the direction of push but the trailing edge becomes the leading edge.

It exploded just as he lifted off; sounded like someone fired both barrels of a 12 guage shotgun.Chuck,

I've heard about people mistakenly mounting props backwards... but never heard about the predictable result.

Didn't I also read in an old Rotorcraft magazine... or maybe it was you who once mentioned... how on more than one occasion a beginner gyro pilot had mistakenly mounted Bensen rotor blades upside down and tried to fly with that way. Obviously they would have to rotate clockwise (viewed from above). Didn't work too well as I recall.

John L.

[gyropilot]

OK... so I lied about flying with Dragon Wing blades turning backwards!

Come on folks, EVERYONE should know that Dragon Wing blades are twisted the wrong way for reverse autorotation! Otherwise I'm sure it would work. :D

The video is purely an optical illusion created between the frame rate of the camera and the blade rpm. Pretty interesting to watch.

However, some of what I did say was true. Even with the blades turning the correct direction, I did have a wonderful cross country flight on Sunday with some of the best fuel economy I've ever experienced. I also made one of the stupidest flying mistakes I've done in a long time... which thankfully had a non-eventful outcome. It was a real wake up call. I'll start a new thread under the GyroBee forum with all the details.

Regards,

John L.

[KenSandyEggo]

There's a guy at my field that was seen trying to hand-prop his Ercoupe prop in the wrong direction. He later wound up crashing onto a highway on short approach and flipped over. Wonder if there's a coorelation?

[C. Beaty]

Now that makes perfect sense,KJ. Doesn't cut your hands if you pull the blunt edge.

[automan1223]

You know you guys you ever look at a rotating fan in artifical light. At some points it seems like you watch the blades go backwards and strobe out of time enought with the light to catch the effect. The camera is being tricked into thinking that.

Even if the video is not moving in reverse the movements of the camera appear to move in reverse. Funny how us humans can see something so subtle and pick it up it just looks way wrong.


show me a video of start to take off and then I will believe it.

Jonathan

[KenSandyEggo]

You can use the "barn lights" mounted on the hangar rows at most airports to verify your prop rpm.

[gyropilot]

John,

Interestingly, I just recently had a heated debate with an old fellow that had convinced himself that gyro blades would do better turning backwards and that the gyro community was mistaken on the concept of autorotation.Seriously?

Once when passing through my old home town after recently graduating from Army helicopter flight school, I met up with my former high school metal shop teacher. Being a mechanically minded kind of guy, he wanted to know all about how helicopters worked, so of course I obliged him with the volumes of aeronautical knowledge (I thought I had).

He all but refused to believe that a helicopter is more or less supported on a self-created "cushion" of vectored air! Instead, he had the notion that somehow the rotor blades made the helicopter "swim" through the air... presumably like the fins on a fish. What he thought held it up beats me. I was a little shocked at all this because he was otherwise a very sharp self-taught guy.

I ultimately left without feeling I'd succeeded in changing his mind.

John L.

[RHerron]

John,

Yes, seriously. This fellow is as smart as they come in every other respect that I know anything about.
He is absolutely convinced that, unbeknownst to us, the blades are actually turning backwards (like your wonderful experience!) when we fly.
He believes that all the information on the theory of autorotation is totally wrong and ,as a group, we are all brainwashed.

Ron H

[birdy]

Reckon I'll stay brain washed,and it don't take much to wash my little brain.

[thallett]

Best APRIL FOOLS I've seen in a long time, John.

[EI-GYRO]

Did this last weekend (put the prop on backwards).
Sounded terrible, even at idle.
Checked for loose screws.
Found one in head (mine).

Cheers

Fergus.

[Chopper Reid]

My mate one day put the rotors together for me while I was busy ,I quickly inspected and tested the tension on the bolts then threw them on and took off. Well, nothing on the ground prepared me for what was too happen when I took off, normally, the rotors were pretty rough but on takeoff, they were as smooth as silk, I very quickly killed the throttle and landed, on checking the rotors, they werent back to front, but the wrong blade was on the wrong side of the hub bar !! I left them as they were and flew for another 200 hours like that, they were as smooth as silk and performed better than the proper way around.