My latest Helicopter Design

DennisFetters

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Just wanted to release to you guys the first pictures of the latest UAV helicopter I have designed and built here in China. It is now being packed up and sent to the UAV show in Beijing, lasting Oct 20 through 25. I'll be there to answer any questions.

This helicopter is called the Flying Tiger, and it's bases off my Star-Lite series UAV that I few some years ago. However, this version is powered by a 582 Rotax with a new PEP exhaust system I just built for it, pumping out 78hp. This baby can pick up 440 pounds of payload and fuel. It also has all new transmissions, blades and frame. Every part for this aircraft is special designed and built by me, and was no small job doing it all here in China.

It also has a new style rotorhead built especially for high speed and stability, utilizing a combination double-separated double-teetering system that has the stability of a fully articulated system and the simplicity of a two-bladed teetering system. I also came up with a way that virtually eliminates the rotor systems Coriolis effect, but still using a simple elastomer damper system to handle the deferential airspeeds between the four rotors during forward flight. I also was able to come up with a modified control system that can control from 2 blades up to 6, which is much advanced from my old Mini-500 system. The new system is under patent pending.

Flight testing will begin sometime after we return from the Beijing show.

I'm in a hurry now to get it to the show, so I'll post more internal pictures later. Enjoy.

Dennis Fetters
 

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...However, this version is powered by a 582 Rotax with a new PEP exhaust system I just built for it, pumping out 78hp. This baby can pick up 440 pounds of payload and fuel. It also has all new transmissions, blades and frame. Every part for this aircraft is special designed and built by me, and was no small job doing it all here in China....

...The new system is under patent pending.

Dennis, it looks good. All the best with testing!

What are the anticipated missions?

Are suitable four-strokes difficult to source in China?

Can quality parts be had in China? They like to tell us the reputation for poor quality has more to do with US demands for lowest possible price than with Chinese manufacturing capabilities.

Regarding the patent pending, I gotta ask...is that actually meaningful in China?
 
Dennis- Very impressive! Thanks for sharing. I can't tell on my cellphone, but does your tail rotor have a delta hinge in it? What cruise speed and range sare you expecting out of your helicopter? Beautiful design. Stan
 
All controls are from the shaft? Keeps it clean in rotation. Looking good Dennis. I would love to see pics with the cover off.
 
Man….that whole machine is impressive….but especially that rotorhead! At first I was puzzled why the articulated hinge line was above the blade centerline….then I noticed a companion star hinge at the same level below the above hinge line. It appears that star has a larger hole than the mast diameter, allowing it to move toward the highest coned blade. Makes a good coning blade stop too.

Simple outstanding design Dennis….I truly hope it flies as well as it looks!
 
Dennis,

I have a suggestion! How about developing some new gyro technology for import to the US. Like three or four bladed rotor systems. Rotor blades would be nice too...larger one not available here. Four places gyros and new gyro engines. Both piston and small turbine engines would be great! Make them inexpensive so the average homebuild can afford them. Sorry, just dreaming, lol.

P.S. That's a beautiful aircraft!
 
Dennis,

An impressive looking craft. Congratulations.
ThumbsUp.gif


Is the rotorhead an Offset Bi-teetering - Rotor Hub?


Dave
 
Hey, I weigh less than 440. Let me ride. Strap me to the bottom. Looks amazing.
 
Just wanted to release to you guys the first pictures of the latest UAV helicopter I have designed and built here in China. It is now being packed up and sent to the UAV show in Beijing, lasting Oct 20 through 25. I'll be there to answer any questions.

This helicopter is called the Flying Tiger, and it's bases off my Star-Lite series UAV that I few some years ago. However, this version is powered by a 582 Rotax with a new PEP exhaust system I just built for it, pumping out 78hp. This baby can pick up 440 pounds of payload and fuel. It also has all new transmissions, blades and frame. Every part for this aircraft is special designed and built by me, and was no small job doing it all here in China.

It also has a new style rotorhead built especially for high speed and stability, utilizing a combination double-separated double-teetering system that has the stability of a fully articulated system and the simplicity of a two-bladed teetering system. I also came up with a way that virtually eliminates the rotor systems Coriolis effect, but still using a simple elastomer damper system to handle the deferential airspeeds between the four rotors during forward flight. I also was able to come up with a modified control system that can control from 2 blades up to 6, which is much advanced from my old Mini-500 system. The new system is under patent pending.

Flight testing will begin sometime after we return from the Beijing show.

I'm in a hurry now to get it to the show, so I'll post more internal pictures later. Enjoy.

Dennis Fetters

The UAV you are talking about is in fact the SUV 200 and entirely developed by The Hunan Sunward Technology Co., Ltd under the direction of Professor (PhD) He Qinghua and his team of professors, doctors, masters and senior engineers, senior technicians and other components of the technology development team. SUV 200 and was ostensibly built for the monitoring of power lines. Rated at a cost of $1.4 million dollars and since its payload is only 200kg makes it unviable for the military. It is equivocal to claim it is your creation, Professor a PhD, He Qinghua (he is aware of your fibs too)and his team at home and abroad for many years have closely tracked the latest developments in the field of general aviation and are involved with Tongliao /Condor Albert Airlines (Shandong Province) into the future development of the Aurora SA60L (nothing to do with your either) and already in use the ultra- light aircraft spraying equipment and aircraft seeding equipment. Your Gyrocopter while it was photographed amongst other crafts for a company advertising , I am a afraid to say, it won’t be used. You see, in China not all Chinese are green. By the way,any patents, if applicable, will be the property of The Hunan Sunward Technology Co., Ltd

Thanks
Albert
 
Most impressive Dennis!!!

Way to just build it, most excellent!
 
I think you’re wrong, Albert.

This parallelogram linkage does nothing but lock in coning angle and doesn’t look to be the work of “professors, doctors, masters and senior engineers, senior technicians and other components of the technology development team.” If so, they need to study simple geometry.
 

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Albert I've seen Mr Fetters works and YOU'RE CLUELESS This machine was designed by Dennis 100%. Its a next gen of his star lite UAV that flew at Corona Air port,Seen the drawings and talked to Dennie before the flood. Dennis may have issues with other people, But what you see in the posted pictures is a Fetters design and all the teams & engineers and professors are window dressing and have no idea how to build anything original.
Damn Albert Get a refund on that Fine Education you have, Aviation is too small a world to keep pulling boners on a daily basis.
 
I think you’re wrong, Albert.

This parallelogram linkage does nothing but lock in coning angle and doesn’t look to be the work of “professors, doctors, masters and senior engineers, senior technicians and other components of the technology development team.” If so, they need to study simple geometry.


Chuck,

A link to information on this Offset Bi-teetering Rotor Hub was given in post #7. A couple of points of interest are;

~ The offset bi-teetering rotor provides more control authority then that of the teetering rotor, and it has a virtual teetering hinge at the same location that a conventional teetering rotor has its actual teetering hinge.

~ Boeing patented this idea in 1987. "September 26, 2007 ~ Maybe this idea ain't new. See; US 4,681,511 ~ Low Vibration Helicopter Rotor ~ Boeing ~ July 21, 1987. It was referenced in Dennis Fetters' patent 5,163,815."


Dave
 
Sorry, Dave. The virtual center of a parallelogram linkage lies at infinity.

It is possible to mimic the behavior of a teetering rotor with a trapezoidal linkage.
 

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Chuck.

Perhaps I should have included this drawing from the link in post #7.

It is not the center of the parallelogram it is the center teetering.

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Dave
 
Chuck, perhaps you, MIT and me are right.

It appears that we are looking at two different situations. Yes, the frame of the bi-teetering hub is a parallelogram, but, the points on the parallelogram are not directly involved with the point of the virtual center.

This is the lower drawing in post #17, in .dwg format, which can be expanded to any size.

What is constant is that a line between the 'Centers' of the 2 blades will pass through the virtual center point on the hub, irrespective of the teetering angle.

The analogy is that a line between the 'Centers' of the 2 blades will pass through the teetering center point on a conventional teetering hub, irrespective of the teetering angle.


The Boeing patent also explains this, perhaps better than I do. :eek:


Dave
 
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My last shot, Dave. You get to have the last word.
**********
OK, one final thought. Tilt the rotorhead left/right with the rotor positioned per your illustration.

With a teetering rotor, the blade CGs are not drawn in toward the center of rotation.

With offset flap hinges they are. This would be another way of measuring centrifugal pitching couple.

Your arrangement of linkages does not alter the amount by which CGs are drawn toward center vs. shaft tilt. Therefore shaft tilt moment does not change between simple offset flap hinges and your parallelogram linkage.
 

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