Tail Boom design

[Terry]

I am really impressed with Chuck's gyroplane. The layout looks to be all business.

But that tail boom is ugly. In fact, all pusher gyroplanes look like an afterthought, a collage of parts hastily and handily thrown together. No offense intended, most simply look like an erector set project.

So, what about a tail boom that exits through a combined reduction sheave and propeller hub? The boom could double as the engine mount and shaft for the propeller hub and sheave.

Has anyone tried something like this?

Imagine Chuck's clean, lean CLT idea with a two inch diameter, quarter inch wall 2024 tube extending far enough through the hub, past the prop to mount a tail boom. All this with the control cables running through the tube. Looking at Chuck's current propeller, it doesn't look like it would be too difficult to adapt some of the hub parts and blades to a larger hub and bearing.

Just some ideas on topic.

[Passin' Thru]

So, what about a tail boom that exits through a combined reduction sheave and propeller hub? The boom could double as the engine mount and shaft for the propeller hub and sheave.

Has anyone tried something like this?

Terry, there is someone who visits the forum who is building one just like that. I can't remember his name or find the threads but he posted pictures. Anyone remember?

[RotoPlane]

Yeah, I remember that one too. I tried to find the post, but I seem to have an inability to make the forum search find anything.......

[RotoPlane]

I was thinking along the same lines as you Terry, but I am building a UL and the extra weight put a stop to that idea. Also it is not a simple design, not to mention the high cost for large bearings.

Chucks tail boom is…..distinctive….it grows on you. It also is a good way to use a large diameter prop and still have CLT. Granted, the vertical stab could use some different lines .

[dinoa]

I saw one in an article about the "Bois" gyro round up in France some years back but cant remember the publication (It may have been an English PFA magazine). Maybe one of the French members can help.

Dino

[PW_Plack]

I've doodled something like that, but I have no idea what it would take to make the prop hub work. My thought was to use a belt reduction drive from an engine mounted atop the outer tube, and be able to pull a couple pins and quickly detach everything aft of the prop by sliding out the tail boom. (Which would also be necessary to change the belt.)

Most of the compromises we see in gyroplane designs are made to reduce cost or make for simpler construction. I've been interested in compromises that would allow low manufacturing costs and ease of transport and shipment. I'd love to see a way to allow carrying the machine in a six-foot pickup truck bed with minimal overhang. A removable, coaxial tail boom would help, and when removed would also allow a very steep departure angle without a vertical stab, rudder and tailwheel dragging on the ground during ramp loading.

[phantom]

I did one years ago and it is not as simple as it seems at first glance. My first attempt was to simply put bearings on the boom, this led to vibration and cracking problems. the only thing that worked after much wasted time and metal was that I happened to have a compleat nose wheel from, I think it was a PBY and the axel was hollow and big enough for the boom to pass through without touching, this was mounted on the bottom of a 640 rotax and the whole thing was mounted to the mast on rubber mounts, a peice of rubber hose was pressed into the bore to prevent boom damage on rough ground as the engine and redrive could move around quite a bit. What did I gain? a funny looking machine that weighed about 50 pounds heavier than my previous funny looking machine.

[Terry]

Originally Posted by PW_Plack

I've doodled something like that, but I have no idea what it would take to make the prop hub work. My thought was to use a belt reduction drive from an engine mounted atop the outer tube, and be able to pull a couple pins and quickly detach everything aft of the prop by sliding out the tail boom. (Which would also be necessary to change the belt.)

Most of the compromises we see in gyroplane designs are made to reduce cost or make for simpler construction. I've been interested in compromises that would allow low manufacturing costs and ease of transport and shipment. I'd love to see a way to allow carrying the machine in a six-foot pickup truck bed with minimal overhang. A removable, coaxial tail boom would help, and when removed would also allow a very steep departure angle without a vertical stab, rudder and tailwheel dragging on the ground during ramp loading.

I suppose the biggest problem with the idea of a tail boom extending from the engine/drive unit would be vibration damping. Maybe it's an idea before its time.

[Alan_Cheatham]

Here ya go guys, link to former thread on this subject:

http://www.rotaryforum.com/forum/showthread.php?t=14869

[RotoPlane]

I thought I deleted this, but it was on my back-up drive. The tail controls went through the 3" boom. The driven pulley and tail boom assembly are solid to the frame. A spring-loaded belt idler keeps the belts tight as the engine moves around. I was going to use WarpDrive blades and make my own split hub that bolts to the pulley. I think this would work, but it is too heavy for my UL. The spacer and nut that holds the bearings is not shown.

[All_In]

Originally Posted by Passin' Thru

Terry, there is someone who visits the forum who is building one just like that. I can't remember his name or find the threads but he posted pictures. Anyone remember?

@Terry
More info:

It was her name and she only posted once with a picture. She had a unquiet cabin too! I did search for it as I did respond but I talk to much and can't find her post!

@Ed
That looks very similar to what she must have done. It was a very cool looking design I wish I could find the post for you to see!

[Passin' Thru]

Here it is! http://www.rotaryforum.com/forum/showthread.php?t=20191

John, the builder's name is Dana, but that don't mean nuttin'.

[All_In]

Thank you Pete! I PM'ed her (I think) and when she responded I found out he was a she!

PS
I don't remember exactly, but I do remember being surprised that he as a she!

[RotoPlane]

Yeah Pete.…I think that is the one I remember. This is making me re-think the boom thing…..dumb it!

BTW….Dana is a guy; he had a wife at one time.

[Terry]

Originally Posted by All_In

Thank you Pete! I PM'ed her (I think) and when she responded I found out he was a she!

PS
I don't remember exactly, but I do remember being surprised that he as a she!

I even posted on that thread and had forgotten about it in four months.