Tail design

[MadMuz]

That"s more like it

[MadMuz]

A story I heard along time ago when I was building my first machine in Quentins workshop in the early 90"s,

[Echo]

You can hotwire any shape you can think of .

[t-bird]

Thanks EchoWhere did you get the plans for the Gyro that you have build ?Really a good looking machine.

[Echo]

..........

[Disco]

How"d you go with Solidworks Echo.

[Echo]

I used a pencil & ruler ......then gave it to someone way smarter than me to put on SW

[gyroo]

Howdy again, T-BirdJust saw your 2nd drawing and the tail rendering as well.I downloaded the Hornet documents and had a close look at them. The documents seem quite comprehensive, but I am personally not aware of any Hornets actually flying anywhere. I didn"t see any obvious dangerous faults, but there were quite a few parts I would have made differently. As such, I would place a big CAUTION sign up, because the internet is full of people who dream up apparently credible designs, but many of these internet "designers" never seem to do much flying (if at all). Ralph Taggart"s Gyrobee is the clear exception, which was an outgrowth of Martin Hollman"s Bumblebee, and the current producer of the "Bee" line is Star Bee Gyros in South Carolina. They have a huge range of parts available.As to your own design - well, you"re getting there - but what"s putting me off quite a bit with your renderings is I"m having trouble figuring out what the longitudinal axis of your design is. Is the front keel beam/tube meant to be horizontal in flight? I"m assuming you"re having trouble mastering your rendering program. Maybe some good old butcher"s paper and pencil and ruler might be more effective?I see you"ve lowered the engine, and I"m assuming that you"ll soon be placing the HS parallel to the prop axis and the prop axis parallel to your longitudinal axis.Please stick a tailwheel on it please as well.

[t-bird]

Hi MarkI will put in the longitude axis in my design If I figure out how to do it in Solidworks. The reason for Solidworks is to be able to Waterjet my brackets and plates. It also calculates my CG. I have a various Asra articles on homebuildingYours is one “home building getting it right on Paper”. Then there is one on stick designs.Hole dimensions and distances from sidesI have the Gyrobee plans , but I wanted something a bit bigger. I agree that the Hornet is not perfect but I have used the plans for the dimensions.My design started by taking the ELA frame and extending it not kinking it up and not including the extra horizontal part. The idea for the kink in the tail comes from Genesis

[RossM]

what are the pros and cons of having a vert stab/tail as one?, rather than tail hinged of vert stab.Any vert stab with horizontal stab attached where the whole stab pivots all seem to be tall tails and supported at the top back to the mast.If a horizintal stab were attached to vert stabs [like in pictures attached], will forces just pull the tail off?{Yes, I know the hor stab are not attached to vert in pictures, just showing pivot tail in short tails}

[MadMuz]

I"m with you Ross, I worry about a couple of things with full flying tails as opposed to a fin with a rudder swinging off it. Of course, a well designed tall tail is awesome, with the engine running especially, but full flying vertical tails only attached at the pivot point make me nervous.

[gyroo]

Howdy Ross,You ask an extremely interesting question. The vertical stabilizers in your pictures are what I would call "all-moving vertical stabilizers", whereas the more conventional layout is a fixed and braced vertical stabilizer to which a rudder is hinged.All-moving surfaces are fine for machines like F-111s or F/A-18s, where their elevators were/are of the "all-moving" variety. They move on immensely strong, incredibly engineered and hideously expensive pivot bearings. Coming down to "Gyro-World", I have real doubts that all-moving VS"s - other than tall tails with upper and lower pivots - are best practice. In other words I think they are more trouble than they are worth. I say this because an all-moving VS with a single lower pivot is quite difficult to engineer soundly. In fact, one of the factors evident in the "Gyroz" design and which is likely to have played at least some part in the Nowra fatality earlier this year, is that Gyroz all-moving VS"s are known to become noticeably sloppy in service.In contrast, the VS of a gyro that has a fixed VS can be relatively lightly built because it can be braced by cable supports from the HS. The rudder is then hinged from the VS.Another point I"ll make is that an all-moving VS might conceivably go "hard-over" if you have a rudder cable failure, even if the all-moving VS is properly mass-balanced. In fact, that is precisely what happened with the Nowra fatality when a bracket retaining the rudder push-pull cable shifted position. The Gyroz in that accident literally turned sideways in flight and then rolled over into the relative airflow.So, give me a good old conventional fixed and braced VS any day. If the fixed VS is about 40% and the hinged rudder is about 60% of the vertical surface area, then if you have a cable break then at least the fixed VS might give better residual directional control in the propwash than an all-moving VS experiencing a "hard-over" situation.Cheers,Mark ReganMelbourne

[gyroo]

Hi again, Ross -My sermon actually didn"t really answer your question. You were asking what effect would plonking a HS onto an all-moving VS have?

[MadMuz]

All-moving surfaces are fine for machines like F-111s or F/A-18s, where their elevators were/are of the "all-moving" variety. They move on immensely strong, incredibly engineered and hideously expensive pivot bearings. And they are controlled by mega buck computers to bootAnother disappointing thing I find to blame on the new euro tubs and "pretty" machines, is that people are looking away from basic, fun, simple and functional designs that are time proven, and now are trying to emulate the fancy machines and, to me anyway,