Tandem gyro plans

joe nelson

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I have owned an AA-7B, Quad City Challenger, WAR P-47 and have flown several other type
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Dave,

I have been working on my shop to make enough space to work on the tandem project. You wouldn't believe the amount of junk that was hauled out of here in the last few weeks. I filled a 10 yard dumpster with scrap wood and various other material to get to this point.

The first thing I want to do is to build a trailer to tow behind my truck to mount rotor heads on. It'll have a long tongue (20' pipe) to give a little room to move around when testing control systems.
 

davh12

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Joe....My basement is the same way...........boxes of bearing, hiems, thrust bearing, micro bearing, scarp aircraft aluminum and carbon fiber. I've always managed to find a use when I need some unique scrap.......especially Cf with small scale stuff.
 

joe nelson

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Location
cincinnati,ohio
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I have owned an AA-7B, Quad City Challenger, WAR P-47 and have flown several other type
Total Flight Time
12000hrs approx
What I've been thinking about is a three blade head with servo flaps. It will have strap packs like a Hughes 500 for the flapping and pitch hinges. The blades will have a cord of 8.5 inches and 13 feet in length. Servo flaps will be located at the 70% station on each blade with the same ratio in size as the Kaman helicopters.

In the next few days, I'll start drawing up the prints for the head itself. The same waterjet CNC machines will be used to cut out the heads as was used for straps that I had made two years ago.

It feels real good to get back to testing!
 

davh12

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Few UAS on the "govy" side
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Joe,

Are you going full scale now? or just starting to fab certain parts that you'll know that you will need for a full scale later?
 

joe nelson

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Location
cincinnati,ohio
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I have owned an AA-7B, Quad City Challenger, WAR P-47 and have flown several other type
Total Flight Time
12000hrs approx
No Dave, this is just a larger scale to compensate for my fat fingers, lol. My problem is at the scale of my earlier models was too small for me to see and work on accurately. The only part that may be used later is the head itself if it holds up to my testing.

My first goal is to see if the strap pack with servo flaps will work together or will be too soft in pitch to work without flutter. Next is to see if the servo flaps will add too much drag to be used on a gyro rotor.
 

hillberg

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The H-2 Kaman used the UH-1 strap pack in the head & used a stop system to lock flap,feather & pitch is limited till rotor RPM was fast enough for the servo flaps take effect,
 

davh12

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Few UAS on the "govy" side
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none, except as LZ passenger and vertical "rope" descents
So 8.5" chord and total platform length 13.......? You may have to tow it behind your truck. What kind of power plant are you going to use?
 

joe nelson

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Location
cincinnati,ohio
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I have owned an AA-7B, Quad City Challenger, WAR P-47 and have flown several other type
Total Flight Time
12000hrs approx
Thanks Don, I'll look up some pictures on line to see how the H 2's head is set up before I start cutting metal.

Dave, Each blade is 13 feet long. That's the length that I'm guessing should allow good longitudinal twisting of the blade. There's 27.7sq ft of lifting surface with 8.5 inches of cord. All of this will be mounted to a trailer towed behind my truck by a 20 foot long pipe tongue.

The rotors in the pictures you posted are of a criss cross system. This was tested by folk here on the forum with mixed results several years ago. The pictures on the web sites you posted were of a European gyro with glass blades. From my understanding the blades crack at the root due stress...maybe they need drag dampers.
 

hillberg

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The Pit Bull gyro tested the 4 blade set up late 90s, It worked good but no one would spring for the extra cost so the project died.
 

davh12

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Rock Island IL
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Few UAS on the "govy" side
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none, except as LZ passenger and vertical "rope" descents
HAHA...Joe what will your neighbors think when you go towing that down the road?....But if it works.........Charlie Mike.
 

joe nelson

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cincinnati,ohio
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I have owned an AA-7B, Quad City Challenger, WAR P-47 and have flown several other type
Total Flight Time
12000hrs approx
Dave,

There's a closed airport nearby with long runways. My neighbors are accustom to me after living here for 30 years, lol. If they ain't...well you know the saying. Several of them are frequent visitors to check out my projects or get a free beer from the frig, but they are always quietly supportive.

Today, my youngest son and I were driving the mini jeep around the yard. That was the most fun we've had together for a long time. He has been showing a lot of interest in the tandem project lately. I hope he jumps in with both feet...helps his PTSD.
 

davh12

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Messages
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Location
Rock Island IL
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Few UAS on the "govy" side
Total Flight Time
none, except as LZ passenger and vertical "rope" descents
yeah.......mine as well....Keeps my mind occupied when I do mechanical problem solving. And wood working. Does do much for nightmares, but I have a good wife. She's understanding and a big support.
 

joe nelson

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Location
cincinnati,ohio
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I have owned an AA-7B, Quad City Challenger, WAR P-47 and have flown several other type
Total Flight Time
12000hrs approx
Here's the mini jeep project....cooompleeete! Now it's time to get back to my gyro project.
 

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joe nelson

Senior Member
Joined
Jan 20, 2007
Messages
1,297
Location
cincinnati,ohio
Aircraft
I have owned an AA-7B, Quad City Challenger, WAR P-47 and have flown several other type
Total Flight Time
12000hrs approx
Today, the temperature in my shop was warm enough to work on my tools. I needed to get them ready to start working on the tandem project.

An inventory was done to determine how much wood and metal is needed to build the larger blades. Enough T88 glue is on hand to make 10 individual blades. This should keep me busy until spring.
 

davh12

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Joined
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Messages
337
Location
Rock Island IL
Aircraft
Few UAS on the "govy" side
Total Flight Time
none, except as LZ passenger and vertical "rope" descents
Jeep looks good, Joe. grandson looks like he's enjoying it too.
 

joe nelson

Senior Member
Joined
Jan 20, 2007
Messages
1,297
Location
cincinnati,ohio
Aircraft
I have owned an AA-7B, Quad City Challenger, WAR P-47 and have flown several other type
Total Flight Time
12000hrs approx
Both my grandsons and granddaughter enjoy driving it. They think that they're race car drivers, just ask them, lol. They've been bugging me to let them drive it in the snow...sounds like loads of fun but cold.

I've been trying to work in my shop but it's too cold for the glue to dry...it needs 68 degrees to work and I only have about 60.

One thing that has been done was to make the follower for the swashplate gimbal. The grooves for the retaining snap rings have been cut to keep the linear bearings in place. It still needs three lugs welded and tapped for the gimbal and scissors to mount to.
 

davh12

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Joined
Jun 11, 2010
Messages
337
Location
Rock Island IL
Aircraft
Few UAS on the "govy" side
Total Flight Time
none, except as LZ passenger and vertical "rope" descents
Maybe a wood stove in your shop would help..that's what I want to do when I replace the metal shed when I get out.
 

joe nelson

Senior Member
Joined
Jan 20, 2007
Messages
1,297
Location
cincinnati,ohio
Aircraft
I have owned an AA-7B, Quad City Challenger, WAR P-47 and have flown several other type
Total Flight Time
12000hrs approx
Dave,

I'm a little ahead you on this one but thanks for the though. I'm headed over to Harbor Freight tomorrow to buy a large electric heater or two. A wood stove would be the best choice but there is no way to vent it from my shop.

Another thing that I'm doing is changing my tool post on my lathe. I'm looking at a quick change post from Grizzly so it won't take so long changing tools. Also, it's about time that I buy a small mill to compliment the lathe.

There's a fellow on youtube that has made tutorials on machining that were very good. I believe he is retired high school shop teacher who does the videos as a hobby. He is a wealth of knowledge to folk like me with a limited background. His website is www.tubalcain.com.
 
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