Trifecta

[Doug Moon]

No. They are 1/8" thick at the TE with an 1/8" carbon fiber cap.  The elevators were tapered from 1/2" at the LE to 1/8" at the TE.  They are imbedded into the stab and not sealed.

Ken

They only stick up 1/16" top and bottom? Just curious because when I went to a 2 bade on my plane it developed a slight hunt. If this might fix it I will try it.

[Ken Culbertson]

They only stick up 1/16" top and bottom? Just curious because when I went to a 2 bade on my plane it developed a slight hunt. If this might fix it I will try it.

Close.  I just measured.  I sliced the strip by eyeball then centered it.  It was 5/16 wide and 3/32 sticking up on each side.  They go the full length of the elevator.  Keep in mind that Trifecta is twin tail so I am already blocking the vortex.  That may or may not have anything to do with anything but it does corner much tighter with the same handle effort.

I know you are not electric but one surprise was the battery draw did not go up.

Ken

[Ken Culbertson]

Today was the test of the Gurney tabs in full pattern mode and as Bob stated, "they are not coming off".  The overall control difference was worth it alone.  Corners about 2' tighter with the same effort and just as smooth.  It may have been wishful thinking, but I also felt that the handle pressure on corners was less. Tracking in all maneuvers was better, noticeably in the RWO and hourglass.  I tried something in my inverted flight to see if there was any improvement at different altitudes.  Interestingly at 2' and 6' the plane was rock steady but at 5' it felt like it wanted to wander a bit.  We have a domed circle and "rulebook" 5' here is about 6 1/2' above ground.  I have been trying to find the right altitude for level that doesn't look too high.  Another surprise was how easy it was to hold the takeoff down.

One thing that has sparked my curiosity.  I felt a larger improvement in corners than I expected.  Could any of that be the logarithmic since it produces a wider flap/elevator ratio?

Crist Rigotti tried them today.  His comment upon landing was the same. "They stay on".  He is experimenting with width.  I will leave it up to him to report on that if he so desires.

Ken

[Matt Colan]

One thing that has sparked my curiosity.  I felt a larger improvement in corners than I expected.  Could any of that be the logarithmic since it produces a wider flap/elevator ratio?

In my experience with them, I don’t think so. With the balsa wedges and the layers of tape versions I’ve tried, the corners have been better and easier. That was the biggest difference in them that I felt with them on, cornering could be harder and still come out dead flat without needing excessive control force…just more consistent

[phil c]

Isn’t Joe Gilbert whupping a** with a Ringmaster? That may be the ultimate trifecta. A little carbon here, a modern engine there, what’s not to like?

You have got that right,  Larry.  I've watched and judged Joe several times.  He used a very well-built Ringmaster.  Without measuring, it looks well within anything that might have been done in the 50's and 60's.

Most of his presentation was well-practiced PRESENTATION of the maneuvers.  He always gave the judges a very good look at the maneuver and never had the plane  give even a hint of falling out of position.  He also was very good and making slight changes to maneuvers to position them better and make them look crisper and cleaner when necessary.  I've never seen a profile flyer do a better job, anywhere.

Phil C

[Ken Culbertson]

Well, I found out today why I should not fly when the wind is directly into the sun.  Flew right through it on a practice RWO and pulled out 5'1" low.  Never saw the plane hit.  Not the way I wanted to start the year.  Guess it is time for the cataract surgery.

Ken

[Crist Rigotti]

Ouch!

[john e. holliday]

Well, live and learn.  Where were your sun glasses?

[Dave_Trible]

Oh sorry Ken..keeps you building.   Brings up a recent bad memory.   Still have time to build a new one before the season starts.

Dave

[Scott Richlen]

Sorry to see that you lost such a nice plane.  I guess you can console yourself with "better to go out in glory than to rot away sitting in an attic/basement".  I guess...

[Ken Culbertson]

Well, live and learn.  Where were your sun glasses?

I was wearing them.  Really cool wrap arounds.  They don't help much when I look directly at the sun.  This one goes into the "@#$% happens" category.  After I get over how stupid I was to fly the RWO into the sun I will fix the plane and go do something equally as stupid.  It will fly again.  Wing was undamaged and all of the power train survived.  I am going to drop the Classic part of Trifecta and put a normal rudder and stab tip plates instead of the twins.

Ken

Ken

[Ken Culbertson]

Well I gave in and replaced the twin rudders.  Actually I just covered the crushed frames with 1/32.   It is almost recovered. Add a little trim and back to the RWO rehab sessions.
Found some tail art.

[Ken Culbertson]

Proof of life.  Actually flies better after the repairs.  Certainly looks better!  Going to redo the landing gear.  What is on there now sounds like a shopping basket full of beer cans being pushed over a washboard.

Ken

[Crist Rigotti]

Proof of life.  Actually flies better after the repairs.  Certainly looks better!  Going to redo the landing gear.  What is on there now sounds like a shopping basket full of beer cans being pushed over a washboard.

Ken

Ain't that the truth!

[Dennis Adamisin]

Way. To. Go.  I HATE repairing airplanes, you did great.

Going to redo the landing gear.  What is on there now sounds like a shopping basket full of beer cans being pushed over a washboard.

Ken

Aluminum gear?  I wonder if its possible to mount it on servo grommets?  I also really wonder if that would help???

[Ken Culbertson]

Way. To. Go.  I HATE repairing airplanes, you did great.

Aluminum gear?  I wonder if its possible to mount it on servo grommets?  I also really wonder if that would help???

Wheels made so much noise I had to do something.  Ball Bearings.  Overkill - Absolutely but what is a hobby for anyway!

Ken

[Dennis Adamisin]

Wheels made so much noise I had to do something.  Ball Bearings.  Overkill - Absolutely but what is a hobby for anyway!

Ken

Overkill? No such thing.  Moderation is for Monks, anything worth doing is worth OVERdoing!

[Ken Culbertson]

This poor plane has become the ginni pig of my tiny fleet.  I was talked into trying spades to relieve handle pressure.  So, in the spirit of not discounting anything till I have tried it I put a set that Mark Wood sent me on Trifecta.  Guess what, they worked as advertised.  I am still far from sold on their benefit, but I won't make that call till I have retrimmed the plane for them and flown a pattern trimmed.  I was able to make it through a full pattern on the first flight even with them causing a slight "wings not level" condition. Without the pressure on the flaps, it turns a ridiculous corner and level flight and line tension is unaffected.  I found a slight misalignment in the outboard spade that will need fixing before I pass judgment.  It will take a lot of flights to get used to the feel, or should I say lack of feel, in corners.  I am not sure I want to go there BUT, they do work and offer a real solution for a plane that is heavy on the controls. 

Ken

[Mark wood]

This poor plane has become the ginni pig of my tiny fleet.  I was talked into trying spades to relieve handle pressure.  So, in the spirit of not discounting anything till I have tried it I put a set that Mark Wood sent me on Trifecta.  Guess what, they worked as advertised.  I am still far from sold on their benefit, but I won't make that call till I have retrimmed the plane for them and flown a pattern trimmed.  I was able to make it through a full pattern on the first flight even with them causing a slight "wings not level" condition. Without the pressure on the flaps, it turns a ridiculous corner and level flight and line tension is unaffected.  I found a slight misalignment in the outboard spade that will need fixing before I pass judgment.  It will take a lot of flights to get used to the feel, or should I say lack of feel, in corners.  I am not sure I want to go there BUT, they do work and offer a real solution for a plane that is heavy on the controls. 

Ken

The spades I provided as an example were for an airplane with larger flaps with a recommendation to start off with much smaller ones to begin with. Spades are entirely tunable and can be sized to make the control forces what ever you wish them to be. Within reason of course. On the too large  size  "snatching" can occur where the control goes to full travel if displaced from neutral. Hence the recommendation to first fly with only the mount installed and then increase the spade size gradually. One thing that is very important on the setup end is that the spade is parallel to the chord line of the airfoil and the flap. Another reason for flying with just the mount in order to confirm it is correctly installed. I noticed that even the mount improved the control forces. I'll make a drawing in the next couple of days.

I'm Happy to hear of the successful first flight.

[Doug Moon]

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[Ken Culbertson]

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I agree. 

[Ken Culbertson]

Update:

Revised the spades to have about 1/2 the surface area and reset the AOA to match wing AOA at neutral vs the flap.  This returned the wings to level.  I confirmed that the spade can be used as a "trim tab" of sorts and having it match a tweaked flap was a mistake.  This session was better than the first but there is still a lot of testing to do.  So far I have noticed two things that I like.  First there is less of a panic feeling when the plane starts winding up.  Don't misunderstand, the spades do not stop windup, they just give you a wider range of control and less backpressure as the plane continues to accelerate.   The other was having better control when line tension was low.  This manifested itself in the horizontal and overhead eights.  I was testing in a 15mph wind and aborted the vertical 8 instinctively when it lost tension turning into the wind at the top of the first loop.  I decided to try another and see what it would do if I did not abort and to my surprise it made the turn just as if I had normal line tension.  Same thing with the overhead 8.  Thousands of flights experience said the plane would sag and I couldn't stop it.  Well ,it did try and sag but responded to the controls with almost no line tension and came around.

Lots more testing, including getting as many people to fly it as I can before I build a set for Endgames III & IV.  If others see and feel the same things, I may add them - to the BOTTOM!.

For now, they stay on Trifecta.

Ken

[Mark wood]

Update:

Revised the spades to have about 1/2 the surface area and reset the AOA to match wing AOA at neutral vs the flap.  This returned the wings to level.  I confirmed that the spade can be used as a "trim tab" of sorts and having it match a tweaked flap was a mistake.  This session was better than the first but there is still a lot of testing to do.  So far I have noticed two things that I like.  First there is less of a panic feeling when the plane starts winding up.  Don't misunderstand, the spades do not stop windup, they just give you a wider range of control and less backpressure as the plane continues to accelerate.   The other was having better control when line tension was low.  This manifested itself in the horizontal and overhead eights.  I was testing in a 15mph wind and aborted the vertical 8 instinctively when it lost tension turning into the wind at the top of the first loop.  I decided to try another and see what it would do if I did not abort and to my surprise it made the turn just as if I had normal line tension.  Same thing with the overhead 8.  Thousands of flights experience said the plane would sag and I couldn't stop it.  Well ,it did try and sag but responded to the controls with almost no line tension and came around.

Lots more testing, including getting as many people to fly it as I can before I build a set for Endgames III & IV.  If others see and feel the same things, I may add them - to the BOTTOM!.

For now, they stay on Trifecta.

Ken

The better solution is to move to offset hinges at the 25% chord of the surface. That will provide similar hinge moments as with the spades but not have the sticky outies to snag on stuff and look funny. The step after that is to use an increased thickness surface profile and gap control which will result in improved list coefficient as well.

[Ken Culbertson]

The better solution is to move to offset hinges at the 25% chord of the surface. That will provide similar hinge moments as with the spades but not have the sticky outies to snag on stuff and look funny. The step after that is to use an increased thickness surface profile and gap control which will result in improved list coefficient as well.

I agree, but not practical on an already built wing.  I wonder, would everybody stop at a contest to watch the plane with the funny things on the flaps fly if you couldn't see the offset flap line?  Humm....

[Ken Culbertson]

Duplicate

[Ken Culbertson]

This should be an easy one for the trim experts we have here.  My trim skills are roughly in the early advanced category!
I am having an issue with line tension as the plane comes into the wind on horizontal eights.  I am starting the 8 about 1/8 lap to my right entering the maneuver directly in front of me and directly down wind.  So far so good but then the plane loses line tension as it moves back into the wind both directions.  Same with the squares.  All other parts of the pattern are fine including the top of the hourglass and surprisingly the overhead 8.  Some other relevant points.  The plane has a Trostel CAM rudder generating about 3/32" offset at full deflection on the outboard rudder only, it uses Igor's logarithmic flap horn, and it is equipped with spades on the upper surface of the wing.  The problem increases as the wind increases and is not there at all in dead air. 

If this were the 1st in the series I would suspect that the Rudders are just too large (50 sq" combined) but it is the 4th one I have built and has a rather narrow fuselage. None of the others had this issue. 

Some details:
Lap Time 5.4
63' Eye to Eye Spectra 100lb lines.
62oz W/battery
63" span 690 Sq"
25" 22% Stab
TP 5s 2800 battery
BadAss 3515-710 motor
Jeti Spin Pro 44 ESC
11" nose, 18" tail moments
Basic bench testing - no alignment issues
CG 25% MAC
Leadouts 3/4" behind MAC
11-6 3 blade MAS

I don't think the timer is the issue but I will give you my settings anyway: 
Fiorotti
ESC Base RPM 300
Max                371
Min                 166
Nose Up             8
G-Force            25
Sensitivity        11

Ken

[Doug Moon]

You are under powered for the size and weight.

Or all of the trim things you have added are causing inward yaw and there is so much going on you don't know where to start. One easy way to find out is to start subtracting things until stops then you know where to start. Since you have a timer set it for 2 min flights and start with the offending maneuver. You could find the issue in just a few batteries. If it never stops then you know it's a power situation. If more power is added and still does it then build a new plane. 

But most likely under powered.

Or go faster.

Good luck.

[Ken Culbertson]

You are under powered for the size and weight.

Or all of the trim things you have added are causing inward yaw and there is so much going on you don't know where to start. One easy way to find out is to start subtracting things until stops then you know where to start. Since you have a timer set it for 2 min flights and start with the offending maneuver. You could find the issue in just a few batteries. If it never stops then you know it's a power situation. If more power is added and still does it then build a new plane. 

But most likely under powered.

Or go faster.

Good luck.

Only things added in the last two years are the spades and the new landing gear.  I haven't weighed them, but they could be lighter and I am tail heavy making the leadouts too far forward.  Most likely it is a combination of leadouts and lap time (power).  Mike said it was flying a 5.6.  I checked the CG and found it at 25% MAC.  The leadouts were pretty far forward for that CG so I have already moved them at 3/4" behind the CG.   First trim will be to get the lap time to 5.4.  I think that may fix it.  If it doesn't I will move the CG a % or two fwd.  With the new gear and the spades I may just be a tad tail heavy.  The rest will be readjusting the timer.   It really hasn't been the same plane since that pancaking at the Ash.....maybe it needs a canard?

Ken

[Doug Moon]

Only things added in the last two years are the spades and the new landing gear.  I haven't weighed them, but they could be lighter and I am tail heavy making the leadouts too far forward.  Most likely it is a combination of leadouts and lap time (power).  Mike said it was flying a 5.6.  I checked the CG and found it at 25% MAC.  The leadouts were pretty far forward for that CG so I have already moved them at 3/4" behind the CG.   First trim will be to get the lap time to 5.4.  I think that may fix it.  If it doesn't I will move the CG a % or two fwd.  With the new gear and the spades I may just be a tad tail heavy.  The rest will be readjusting the timer.   It really hasn't been the same plane since that pancaking at the Ash.....maybe it needs a canard?

Ken

Well sounds like you already know the answer to your trim question.

[Ken Culbertson]

Well sounds like you already know the answer to your trim question.

Maybe but is it likely the correct answer or a lucky guess?  When you only get at best two flights a week you can't spend a whole lot of time guessing.

Ken

[Ken Culbertson]

It was as simple as moving the leadouts back 1/4". I still do not know why the problem was only in the outside top corners of the square 8. and not anywhere else including the top of the hourglass or the squares.  I guess that will simply have to remain one of life's mysteries.   

Ken
 

[Doug Moon]

It was as simple as moving the leadouts back 1/4". I still do not know why the problem was only in the outside top corners of the square 8. and not anywhere else including the top of the hourglass or the squares.  I guess that will simply have to remain one of life's mysteries.   

Ken

Well alot of planes have trim issues right in that same area. Moving the LO even a little bit can really make all the difference.

[Dave_Trible]

It could be that by the time you get there the airplane has lost a great deal of momentum with all the turns and then a vertical climb and turn into the wind is just a push too far.   That may be the worst spot in the pattern for that to happen.   Power, engine offset and slightly more outward yaw are probably the cures in the tool box.

Dave

[Ken Culbertson]

It could be that by the time you get there the airplane has lost a great deal of momentum with all the turns and then a vertical climb and turn into the wind is just a push too far.   That may be the worst spot in the pattern for that to happen.   Power, engine offset and slightly more outward yaw are probably the cures in the tool box.

Dave

You are probably right.   Moving the leadouts was change #1.  It was to be followed by increasing base poser, then nose up boost and finally trimming some rudder area.  The wind for the trim flight was only about 10 so I may not be finished with this yet.  I kept the power the same because I get a pretty good boost on the up vertical segments of all of the squares.  That was probably a mistake.  With any luck I will get to fly it again next week.


Ken