Part 103 legal autogyro?

[BrianInVA]

This is a bit outside the usual Legal Eagle questions so please humor me if you have similar interest in gyroplanes, also called autogyros or gyrocopters. If you’re unfamiliar with the concept of a gyro, watch this video explanation: https://m.youtube.com/watch?v=UyduIDPVVlE&feature=youtu.be

There’s a modern gyro with a traditional tractor configuration called the Little Wing Autogyro.



Its uncovered frame is very similar to a Legal Eagle.


Could a Legal Eagle airframe be used to make an autogyro that qualifies as a part 103 compliant ultralight gyro?

The gyro mast might overstress the Legal Eagle airframe but I don’t see it as much less stout than the Little Wing Autogyro. The LE frame has to take the wing loading.

[pappyadkins]

First off, I have these plans... This is what I plan to build one day... I knew a man in Oklahoma that built the Little wings & then built his own design that had similarities to the LE (the rear end) but also had similarities to the Little wing (the front end)... As I've been building the LE - I've often wondered about a combination of the 2 as well...

[BrianInVA]

First off, I have these plans... This is what I plan to build one day... I knew a man in Oklahoma that built the Little wings & then built his own design that had similarities to the LE (the rear end) but also had similarities to the Little wing (the front end)... As I've been building the LE - I've often wondered about a combination of the 2 as well...

That’s awesome, thanks for weighing in! I’m glad to see others grasp the potential here.

Do you see enough of a difference between the two plans that you think the LW airframe could take the stress from the autogyro mast & rotors better than the LE airframe?

I’d love to see an LW Autogyro without fabric covering like the LE. And it seems by eliminating the wings the LE could accept the gyro components and still stay close to 254 lbs.

[pappyadkins]

Little Wings does have an UL version (I think the red picture you had below was a picture of it...) I keep meaning to try & find out how much it weighed... You use to be able to buy a completed (welded) fuse of a LittleWing... If I find any info out, I'll let you know... By the way, Ron is still selling plans... I talked with him a few months back... The plans book has all the versions, including the UL...

[BrianInVA]

Little Wings does have an UL version (I think the red picture you had below was a picture of it...) I keep meaning to try & find out how much it weighed... You use to be able to buy a completed (welded) fuse of a LittleWing... If I find any info out, I'll let you know... By the way, Ron is still selling plans... I talked with him a few months back... The plans book has all the versions, including the UL...

Yes I just exchanged email with him yesterday. Illask about a ul verson.

The Affordaplane airframe would lend itself to a gyro mast:

[BrianInVA]

Does anyone know the weight of each LE wing?

[Dan_]

From the late Steve Kiblinger's web site
++++++++++++++++++++++++++++++++++++++++++

WhatDoesItWeigh?

The paint is NOT thin enough on our airplane!

Fuselage........ 55 lbs [Painted, on landing gear, controls, floor boards and seat installed; no firewall, Instrument panel, battery case, cover, cables/aileron pulleys or seat belts] Powdercoating will save 2 lbs and be a better finish...

Right Wing..... 22 lbs [Prior to exterior varnishing]
---------------------- 26 lbs [One coat of HVLP sprayed Stits Epoxy varnish] A brushed application would save 3 lbs!... 6 lbs per airplane!...         
---------------------- 27 lbs taped with a cross coat of PolyBrush and a cross coat of PolySpray (without the aileron) - another coat of PolySpray will be needed on top of the wing - the flashlight test looked like the stars out in the desert on a clear night - I'm holding off painting until I get a preliminary all up weight...
---------------------- 28 lbs [There is 1.5 cross coats of silver on the top of the wing]...

Left Wing....... 28 lbs [Varnished with HVLP sprayer]
---------------------- 31.5 lbs [ 1.5 cross coats of silver on top of the wing without the aileron and deducting the weight of the gas tank]... We have tried to account for the 3.5 lb difference in the wings and don't have a clue... Parts count and dimensions match...

Ailerons.........  8 lbs [2 ailerons @ 4 lbs each - cross coat of PolyBrush and taped, 1.5 cross coats of PolySpray]...

Wing  Tips....  1 lb [Cross coat of Stits Epoxy Varnish and 3 cross coats of Stits PolyTone]

Fuel Tank...... 3.5 lbs [Holds 5.5 gallons all useable in level flight]

Wing Struts... 6.25 lbs

Empennage.. 6 lbs  [Prior to cover]
--------------------- 7 lbs  [ 2 very light coats of Stits Epoxy primer]
--------------------- 8.5 lbs [covered, one cross coat of Stits PolyBrush and taped]
--------------------- 11 lbs [ 2 light coats of primer, cross coat of PolyBrush and taped, 1.5 cross coats of PolySpray and 3 cross coats of PolyTone on fin and stabilizer]...

Engine........... 86 lbs

Leburg EI...... 2.5 lbs  [ Dual ignition includes 2 Honda CBR 600 coils, spark plug wires, impulse disk and wiring harness]

Battery.......... 7.2 lbs    [ Interstate PC-1270 5.8 lbs and a PC-1212 1.4 lbs for fully dual EI ignition - does not include case]

Peery Prop... 2.5 lbs

Inst. Panel.... 3.25 lbs  [Includes wiring harness and mechanical sensors]

Seat Belts....  2.0 Lbs [Seat belt and Shoulder Harness modified to fit. Started with Aircraft Spruce & Specialities 13-00201 & 13-00701]

Brakes..........            [Avid Mountain Bike manual disk if adaptation works]

Our extra weight is in the coatings, tapes and fuel tank!!!...

If the instrument panel is detachable it counts as baggage!

[BrianInVA]

Thanks Dan, immensely helpful!

A gyro has no wings and no empannage besides light aluminum horizontal and vertical slabilizers. Enclosing part of the tail of the A-plane frame would increase effective vertical stabilizer square footage. This could be done with very light RC oratex.

So subtract Wings (30lbs x 2) Ailerons (8 lbs x 2), Wing  Tips (1lb x 2), Wing Struts (6.25 lbs x 2), Empennage (6 lbs)

582 Engine will add about 10 pounds, fuel seat tank will add 7lbs.

So a net 70lbs savings vs an LE UL.

Now I gotta weigh the Brock frame and rotors. A part of the Brock frame will be a direct swap into the A-plane frame so that will be a wash. The original Brock landing gear can be used for triangulation/ bracing of the gyro mast.

[pappyadkins]

just weighed one of my wing... was 32# + added 1# of paint - now 33#

[Chuck in Indiana]

I used a 4 inch roller to apply about a quart of poly spray with UV inhibitor to the entire airframe.  Varnished with a brush.. spraying is considerably heavier. Still didn't make weight. (Looking over shoulder to see if the faa is following..) Naa, I've been told with authority that if it has one seat and a 5 gallon tank it's an ultralight. They have more important things to worry about.

edit: brain fart.. poly tone.

[BrianInVA]

I used a 4 inch roller to apply about a quart of poly spray with UV inhibitor to the entire airframe.  Varnished with a brush.. spraying is considerably heavier. Still didn't make weight. (Looking over shoulder to see if the faa is following..) Naa, I've been told with authority that if it has one seat and a 5 gallon tank it's an ultralight. They have more important things to worry about.

Based on several months of reading and research, it seems more than half of the part 103 ULs in use are “a bit fat.” Maybe well more than half.

[Chuck in Indiana]

Just do the best you can, all other things being equal, the lighter airplane is the better airplane every time. 

[BrianInVA]

I had a long conversation with one of the gyroplane gurus this morning. He convinced me to forget the idea of building a tractor gyro for now, and just get my Brock KB2 properly modified to accept my 582 motor and get it airworthy. A tractor gyro made from the parts would need to be on a chrome moly frame. The Affordaplane frame would be too heavy.

So after we build our Legal Eagle XL I’ll have enough experience to go back and revisit the tractor gyro idea, but using chrome moly for the airframe.