Though I'm not going to do a build thread on this I wanted to share the project a little.  The wing is mostly done and putting the controls in.  For the most part I'm using the kit wood with only a few changes.  The flaps are a hybrid balsa/granite composite that would need 'power tools' to shape so those are being replaced with some 1/4" I found at the LHS that I'd call 7-8#.  The top block isn't really too bad and would be OK hollowed thin but I'll go 4-6# there and the fuse sides I'm going to cut from 7-8# to replace the multi-piece sides in the kit.  This one isn't about weight, just want one piece sides.  My deviations from the kit so far are to add adjustable lead outs that add a limited amount, but some travel.  The flap horn arrangement on the plans show bending a Veco horn for the tapered trailing edge.  Everything about that bothers me so you can see I'm making split horns for the flaps.  Thought I'd put my Delrin controls in but they are overkill and heavy for this so doing it more conventionally.  Putting in a 3" Fox bellcrank I had with brass bushings JBed in.  This machine will get a new K&B Stallion .35.

Dave

Yes John I did.  That's why it was a BIG DEAL for me to find and build another.  Sort of a living history project.  Had a Fox in that one.

Bill I'd like to see a picture if you can.  I'm going to silk mine with a very thin finish.  I saw a great color photo of one in the Aussie AF that I think I'm going to copy.  It's light grey with a grey/green camo.  It's light enough I think I won't lose it in the trees when flying.  My last camo P40 would flat vanish on me on the bottoms and had to go by feel.  No wonder not much hair on my head!  I have somewhere a picture of one at an English museum in all white-winter snow camo I guess.  That would be easy!

Looks good Dave. Here's another paint scheme you may consider...

That sure is pretty.  Did you ever fly that crate?  I just noticed the canopy is tinted.  That's a nice touch I might do to this one.

Wayne that's a little warp.  Put a small tab, say 3/4" by 4" angled down maybe 15 degrees under the out board wing toward the tip just ahead of the hinge line.  You can use .040 canopy plastic.  Add a 1/2" mounting flange and heat with a heat gun to bend to the desired angle.  Clear bathroom silicone will stick it on until you want it off without a mark on the plane.  Fly the plane to see if its enough/ too much and adjust accordingly.  Don't tweak!!!  Tweak not- break not!  The smallest warp, misalignment or mis-shaping of the leading edge or tip can cause this.  Having just built this elliptical wing i'll attest as to how hard it can be to get this wing straight.  I got creative in jig making.  The wing location in the fuse has nothing to do with what you experienced.  Many of these built and flown without this issue and it  falls within reasonable measures.  Let me know.....

The 'thing ' about that though is that would change the design and would, should make it not eligible for classic competition.   I do tend to see the world through that lens.  I guess if I can't compete with something then I won't build it.  Regardless of the cause the tab should fix it.  Now to the flying field- test flying Asteroid today!

The 'thing ' about that though is that would change the design and would, should make it not eligible for classic competition.   I do tend to see the world through that lens.  I guess if I can't compete with something then I won't build it.  Regardless of the cause the tab should fix it.  Now to the flying field- test flying Asteroid today!

 I agree Dave, and I typically stick with that approach as well. I'm just pointing out that if someone was building one of these and wanted to try to "upgrade" the flight qualities that moving the wing up would be something to consider.

Just as an interesting aside,  I test flew the Asteroid today.  It did exactly what you are describing the Spit does; outside tip down.  Sure can't see any warps but obviously a little something.  In my building thread you will find a full on side view photo of the plane.  No chance really of a vertical CG problem, at least in that direction.  Yet the same issue.  I quickly fixed that before the second flight.  These airplanes are my first with segmented flaps.  The outer 5" are separate from the inner section but tied together with a 1/16" music wire joiner.  This allowed an easy field tweak of about 1/8" on each flap that instantly solved the problem.  What caused it?  Who cares- its history. 

I love Hurricanes ....  prettiest ugly fighter plane ever flown in combat ...

You will have those done before summer gets here. I know you better than that.   Projects for next building season, right?  My self I build year round.  Guess that is why I don't get much flying in.  Would have made it out yesterday, but grand kids and school interfered. 

Well when it is too windy or it's raining, what else is there to do, other than the computer.

Oh... Ah... That's cool Denny!  I like it.  These things just always look good.  I know they can fly well too.  'They' knew what they were doing even back when we were kids...just after Lincoln.  Mine suddenly stopped when I got my  toys from Igor.  Trying to remember anything I ever knew about electronics.  The wing is done and should get back to it soon.  Thank you for the photos.  Like to download those....hmm...

Not much prettier than the Spitfire wing planform.  Tempts me to enlarge and use it on a 'super stunter'.   Inching along.

Dave, you need some 00 silkspan for that bird.   If you want it come by and get it.   Give me a call first as I usually don't get up before 0900 and back to bed about 2000.  Oh, sometimes I even stay up till 2200.

I like the split flap horns ....

Dave, you need some 00 silkspan for that bird.   If you want it come by and get it.   Give me a call first as I usually don't get up before 0900 and back to bed about 2000.  Oh, sometimes I even stay up till 2200.

John I'm going to cover this in that new Thai silk I got.  Cross your fingers!

Bill as a teen I built all these except the Dolphin.  Don't remember ever seeing a Jetco kit in the KC area.  Maybe the jobbers doing business with the hobby shops here didn't carry them.  The one I really screwed up was the Skylark in three ways.  It was pretty but too heavy.  I built my first control hardware for it and it was real junk.  And finally I learned about the sin of sharp leading edges.  I hope to do better next time.

BTW Bill. I found a Red Head Merco .35 to put in the Warburton Tony.  Be nice if the mounting is the same as the Blackstreak.  Haven't checked it out yet.

I met Bill at a Nats (which one?) when he was flying that Skylark.  Very fine it was.  I'm pretty sure he must have had something bigger than the Mac.40 in it though.   Dale Gleason kicks it with a regular size machine w/ Tigre .51.    I'm thinking either Red Head Mac or Series 21 in mine.  I sure don't know what Bill had in his but the airplane was every bit Tigre .46 size and that's what most of us were using at the time.  If there are plans to that available I'd like to get a set.....

John, Bill and I are talking about two airplanes.  The original Sterling kit and an enlarged version that Bill Byles had.  It looked identical but enlarged quite a bit-say 10% or more.  I'd have put it around 700 sq. in.  I did not know it was classic legal.  That would make it at least three or four years older than I knew about.  I sort of think Bills was orange or red.  Maybe he'll see this and chime in.
I put the Spitfire wing as shown on the scale;  14 ounces with one ounce of tip weight and adjustable leadout guide and landing gear installed.  No feather but I'm sure it will be fine.  Going to use a plastic clunk tank and feather light wheels to cut some.  Didn't have those luxuries in the old days.  Not going crazy on finish either.

I met Bill at a Nats (which one?) when he was flying that Skylark.  Very fine it was.  I'm pretty sure he must have had something bigger than the Mac.40 in it though.   Dale Gleason kicks it with a regular size machine w/ Tigre .51.    I'm thinking either Red Head Mac or Series 21 in mine.  I sure don't know what Bill had in his but the airplane was every bit Tigre .46 size and that's what most of us were using at the time.  If there are plans to that available I'd like to get a set.....

Hi Dave,

When I was talking to Bill about the Skylark, he said Ed had built them in 3 sizes.  The one Sterling kitted at a 52" WS, the one he was using when he went to the WC at 56" WS, and a ".60 size" (can't remember the WS).  There wasn't a ST .46 available so he used the McCoy .40 set up by Dick McCoy in his 56" model back in the day.  He was using the ST .46 before his passing in the 56" model.  I'm pretty sure Dale is using the 56" model.  Bill has plans that he did with Ed for the 56" model.  That is the one on my bucket list.

BIG Bear
RNMM/AMM

Those split horns installed.

Just for the record.  You suggest that this wing is not intended for a serious competitive CLPA model.  There is nothing wrong with putting split flap horns on a sport ship.  However, for those contemplating split horns for a competitive CLPA model, it would behoove one to heed the words and practices of a serious multi national CLPA champion who has been quoted that there is no such thing as flaps that are too stiff and for a flap control horn to be too stiff.  That individual goes to great length to avoid using any form of split flat horns on his models though those models have noticeable swept forward flap hinge lines and dihedral.  The problem with split flap horns is that they allow the flaps to flex unsymmetrically because of the different loads on the flaps while maneuvering.  They cause trim problems in roll and yaw that are virtually impossible to correct.  For a sport model, fine, but for trimming for ultimate performance in the maneuvers, split flap horns are to be avoided.  There are solutions to minimize excessive flexing from one flap to the other caused by flexible or split flap horns.

Please note that I am not condemning the example shown in this thread.  I am just explaining that for those that have not experienced these things, that split flap horns are not a good thing to use on a CLPA model intended for serious competition.  For sport fliers, they can work just fine.  But for the golden arms at the top of the food chain, they are to be avoided.

Keith

Hi Keith.  I think this WAS a serious model but I meant more about sizing it up for modern .61+ piped engines.  The design is sound enough.  For a ship this size I think I've made the split horns stiff enough.  My concern about bending a straight horn for the tapered trailing edge is two-fold.  The geometry puts the horn in something of a mechanical bind,  putting wear and stress on hinges and horn.  Also bending the horn here weakens the horn and might fracture the braze.  The split horns at least get around these issues.  I've done this a few times in previous years also with V tailed airplanes where a 30 degree angle made it nessessary.  If the pushrod fork is stiff and close then I don't think there is much compromised.

I am not quite sure what you mean when you write about not wanting to bend the horn.  Of course, a horn that is bent to match the flap forward sweep will bind and resist any deflection.  (However, there is another solution here, but it sort of goes beyond the scope of this discussion.)

You would be surprised that with the relatively small amount of forward swept flaps that is shown in your photo that a single straight flap horn will work.  Then, there is no compromise of excessive flexing from one flap to the other.  I know it does not make sense because intuitively, one would think that as soon as the flaps start to deflect, there would be a bind that would restrict the movement of the flaps after a few degrees of deflection.  That does not happen.  Bill Werwage showed us that with his Juno that appears to have more forward sweep than your wing shows.  My explanation for this single horn operation is that there is enough flex in the wood around the horn as well as flexing in the hinges and the wood holding the hinges that binding due to flap deflection does not start to occur until well beyond the 30 to 35 degrees maximum deflection of the flaps.  I have no small amount of experience regarding this matter.  I am just saying that for those who have not yet delved into this matter of swept forward flaps and dihedral, and top performance is desired, a split flap horn is not a desirable solution.  Particularly when other solutions are available.

Yes, I am sure your model will be fully capable of flying a stunt pattern, and it will probably be totally satisfactory to you.  It is just that better performance can be had with a properly installed single flap horn.  It will avoid trim problems that will be encountered due to unequal flexing of the flaps during the maneuvers, particularly how the airplane responds in all of the eights and four leaf clover.

An alternative is to use "Lucky Boxes" which use only a single horn with the horn wire able to translate inside the flap.  I have the elevators of a scale Swee' Pea Goodyear racer that has 40^o dihedral under each side of the stabilizer with a single horn, using Lucky Boxes.  The operation is completely smooth and there is no "slop" or any excessive flexing of the elevators from one side to the other.

And before anyone jumps to conclusions, the famous multi-time National Champions referenced in my previous post is not Bill Werwage with his Juno referenced above.

Keith

May've mentioned this once before: Fort Benning, GA, 1964, flew someone's Sterling Spit' and was amazed by its performance.  Granted, it had no real finish...a dusting of overall grey paint...K&B .35 GH power.

It was a joy to fly.  Turned extremely tight corners on Squares and Wingover...very close to the asphalt.

Then again, that was with then-24-year-old reflexes.  Wouldn't want to try it today.

Hello Bill.  Thanks for the back story and filling in for my failed memory.  Your big Skylark was impressive to me and sure a beautiful thing.  Skylarks have a special classy look about them somehow,  the distinct rudder shape and unusual cowling to me stand out.  One of the earliest stunters I saw as a youngster was a pretty metallic blue one here in KC built and flown by local legend Ray Reinschmitt.  A thing awesome to me.  Now I'm curious; the original 56" span airplane.  Was the span just longer (higher aspect ratio) or was it larger by scale overall?  In other words what would it take to your memory to get a kit Skylark up to the 56" version?  I bought an after market set of plans off the bay a while back. I should dig those up and see what it is.  Another question is what larger version is classic legal.  Is that the one you had in Washington?  I have a new PA .51 looking for a job.

It's very nice to hear from you and I hope you get out to Muncie one of these times.  I know it's a haul for you.  And thank you for your kind words about the Impact kit.  Wish I could today get the kind of wood I did in those days.  Riley was sure I got good stuff.

I checked the plans I bought-straight kit version.  They do have a full size fuselage drawing that the Sterling kit doesn't.  That seems to be a common thing for Sterling.