Movable tailplane? That is the question.

[Mark wood]

Those are vortex generators. I couldn’t feel any effect from them.  I might try them there again after seeing Mark’s video.

Oh, those. That's the VGs you mentioned for the flaps, got it now. I CADed up some VGs this morning but had to go administer a test before I could send them to the printer. I'm not sure those in the photo are in the right place or they might need to be bigger. From the tufts I think the boundary layer is pretty fat in that area. I've been looking for some information on the wing root fence looking VGs. I can't recall on which airplane I saw them.

The tail cam should have the range to look down far enough but may not be able to focus. If it can't then a wing cam can be crafted, which will allow a good look along the fuselage.

[phil c]

Many thanks guys.
I appreciate your time and effort in replying.
Sounds like a duckfart idea, but hey I had to ask.
I might try one on a small model with dampers to stop flutter.
I will not tell any jokes but as Will Rogers said, "Observe the Government and merely report the facts!"
I will report bck.
Regards to all
John.

Combat use stabilators on practically almost every thing. The problems for Stunt or PA are getting a sturdy mounting for it.  Twin booms were mentioned.  A P-38 with a stabilator would look good.  Several sets of plans are available, or sketch up your own.
I built several planes, quite awhile ago,jet like profiles.  The hinge was a brass tube about 3/8in dia. mounted on the fuse.  The two surfaces had slip fit pieces of aluminum tubing buried in then from the bottom and a snug tube/pin behind the fuselage.  It flew just fine without flaps, but I only had a Fox 25 at the time.  The plane couldn't be too big.

If you want to go bigger, keep the stabilator a smaller aspect ratio and a number or two higher on the wing.  If the stab is too long, say 24 in. span, it will need to be very stiff and probably needs internal ball bearings to keep it smooth.  Plastic ones, which are available would be effective and light. The hinges need to be at about 20% of the chord, 1in in 5.

The stabilator should have a flatback crossection from the high point at quarter chord to keep it from fluttering, and it needs to be fairly thick, 20% or more at the root.  There haves to be balance weighst in the leading edge near the fuselage.  Both are needed to prevent fluttering.

It can be lots of fun designing in before building, if you have an engineer bent,   or is that you are bent engineer! joke.
A twin boom design, like maybe a jet version of the P-38 would be an interesting layout and much easier to lay out-, 3 smaller 3 blade props screaming to provide ambiance.

In the end though, a standard stab/elevator set up is easier to engineer, build and maintain.

[Mark wood]

Phil

I have such a beast in my sights. With all of the hype on twin motor airplanes, the natural progression is to Franken 38. That airplane is next in line after my current effort.

[Scott Richlen]

  Did any of y'all ever build a Peacemaker with a with a sharp L.E. and T.E. on the stab/elevator? How did it fly? 

Yes, but so far, it hasn't flown worth crap.  But that may not have anything to do with the sharpness of the LE and TE of the stab/elevator.

This is an original Top-Flite kit with the molded fuselage that has had a very checkered life.  I started building on it maybe 45 years ago.  Assembled and waiting for covering, the babysitter stepped on it (long story).  Onto the back-burner.  Finally repaired.  During finishing the local hobby shop recommended a new material for fillets they were selling.  It was a polyester.  What doesn't dope go over....?  There is nothing so time consuming, difficult and dis-heartening as digging out polyester fillets.  Back onto the back-burner.  And when you do have polyester anywere you have to get every last bit!!!  Back onto the back-burner again.  And then the thought:"why am I building this for a Fox 35 when an LA-25 will do much better?"  Re-do motor mounts.  Does anyone make a tank that will work well in this?  Build own tank.  Cream and blue: beautiful colors, right?  How many coats do you need to use with SIG cream to get decent coverage......

Anyway, it now has about 5 flights and not much promise.

[Mark wood]

Yes, but so far, it hasn't flown worth crap.  But that may not have anything to do with the sharpness of the LE and TE of the stab/elevator.

This is an original Top-Flite kit with the molded fuselage that has had a very checkered life.  I started building on it maybe 45 years ago.  Assembled and waiting for covering, the babysitter stepped on it (long story).  Onto the back-burner.  Finally repaired.  During finishing the local hobby shop recommended a new material for fillets they were selling.  It was a polyester.  What doesn't dope go over....?  There is nothing so time consuming, difficult and dis-heartening as digging out polyester fillets.  Back onto the back-burner.  And when you do have polyester anywere you have to get every last bit!!!  Back onto the back-burner again.  And then the thought:"why am I building this for a Fox 35 when an LA-25 will do much better?"  Re-do motor mounts.  Does anyone make a tank that will work well in this?  Build own tank.  Cream and blue: beautiful colors, right?  How many coats do you need to use with SIG cream to get decent coverage......

Anyway, it now has about 5 flights and not much promise.

Well, it sure is purdy though.. I like it. Maybe it's just meant to hang around another 20 years or so. I'd fly it and like it.

[Scott Richlen]

   Well, it sure is purdy though.. I like it. Maybe it's just meant to hang around another 20 years or so. I'd fly it and like it. 

Thanks Mark!  When I was in high-school (many, many years ago) I flew out at Fort Missoula with a Cpl. Roseberry who was the Fort's groundskeeper (amongst many other duties).  He had built one and it was beautiful.  Of course, it became a quest on my part to build one like his.  Problem is that when you have a love affair with an airplane, when things go wrong you just walk away until the romance comes back.  Unfortuneatly with this plane, that happened too many times.  And now it is finished but is quite the disappointment.  It is not heavy or anything, it just flies "jinky" - touchy on the controls, but doesn't seem to turn that well and comes out of turns flat.  I can do the full pattern with it, but it is a very ugly pattern.  I'll have to fly it some more and see if there is anything to be done about it.  Only 5 flights so far, so maybe there is hope.

[Mark wood]

Thanks Mark!  When I was in high-school (many, many years ago) I flew out at Fort Missoula with a Cpl. Roseberry who was the Fort's groundskeeper (amongst many other duties).  He had built one and it was beautiful.  Of course, it became a quest on my part to build one like his.  Problem is that when you have a love affair with an airplane, when things go wrong you just walk away until the romance comes back.  Unfortuneatly with this plane, that happened too many times.  And now it is finished but is quite the disappointment.  It is not heavy or anything, it just flies "jinky" - touchy on the controls, but doesn't seem to turn that well and comes out of turns flat.  I can do the full pattern with it, but it is a very ugly pattern.  I'll have to fly it some more and see if there is anything to be done about it.  Only 5 flights so far, so maybe there is hope.

Well, that is true for many of the older designs. The horizonal is not very big on this airplane which translates to not having a very big stability margin. Moving the CG forward is a way. Or what I would do is simply learn to live with it, admire it's original beauty that you fell in love with and accept that it won't be one of the sexy modern models. I recently did a Smoothie for the sole reason I think they're cool. If there is another older airplane in my list the Peacemaker is one of them. I'd want it to be what it is.

[Dennis Toth]

Scott,
Seal the hinge lines and get the balance around the 17% back from the LE, set the center of the leadouts 3/8" behind the CG in the best position. The Peacemaker is a Flite Streak with flaps. It originally had an Oliver Tiger 15 diesel in it. It has a very short couple tail moment, slow the flap to elevator to 1:2 and it will be better in the corners but the biggest change will be the sealed hinge line.

Best,   DennisT

[Air Ministry .]

Allan Barnes in N Z had a ' flying tail ' comp ship tho Ive only seen photos .

I figure a fixed carbon tube pivot / spar , in ply doublers , would be ridgidist .Tail plane push over Ea Side .

Tho spar swiwvling in ply plates , Some with ball races , have been used .

They say 15 % fwd of pivot , and 15 degrees dflection  , anything ive read .

[Dennis Toth]

Back in the 60's there was a couple ships called "Nuts" and "Bolts" that had the full flying tail. It was written up several years back and the writer indicated that it was very touchy but the designer did very well with them. Seems they had the pivot point to far back. The first full flying tail I flew was on the Voodoo combat wing that had the twin booms and hinged with just a bit of overhang. That worked great several others used what could be called an overhange elevator. Red's Stuntwing used it to try to get the flying wing design to turn smoothly. Seems the easiest way is to use the twin boom arrangement. Would be easy to use a tube and wire hinge (I would run the wire full length through aluminum tube with brass at the ends) that would allow removal and replacement of the elevator with different amount of overhang and the same elevator area.

Best,   DennisT