beepee

do335a,

My memory is the same as yours. I also remember the tail hanging a bit low in flight, which would indicate a negative incidence. As stated above, it is hard to build this kit true and get the wrong incidence. Most of all, I believe you need more negative in the h stab than the wing for stable flight. That is more important than the relative incidence to the fuselage.

Have fun,

Bedford

do335a

I fully understand everything that you are saying.

The plane is set up with minus 5 degrees thrust - that's 5 degrees downthrust, if you prefer (and 2 degrees right thrust), minus 2 degrees wing incidence and minus 3.5 degrees stab incidence. These are all in reference to the longitudinal axis of the plane, not some arbitrary line on the plan sheet or the border of the paper.

Here's my reference, straight from the horse's mouth, so to speak:

http://www3.towerhobbies.com/cgi-bin...P?I=LXYXJ7&P=8

SPECS: Wingspan: 89" (2261mm) Wing Area: 1237 sq in (80 sq dm)
Weight: 16-18lbs (7258-8165g) Wing Loading: 30-33 oz/sq ft
Length: 69" (1753mm) Airfoil: Semi-Symmetrical High-Wing
Center Of Gravity: 3-3/8" Back From Leading Edge Of The Wing
Control Throws: High Rate Low Rate
Ailerons: Up & Down 1¼" 5/8"
Elevator: Up & Down 1½" 1"
Rudder: Left & Right 1½" 1"
Cowling: Length, Firewall To Front: 6-3/8"
Height, Rear At Firewall: 7-7/8"
Height At Front: 5-3/4"
Width At Rear: 6-3/8"
Width At Front: 6-1/8"
Engine Down Thrust: 5°
Engine Right Thrust: 2°
Wing Incidence: -2°
Stab Incidence: -3.5°

What you say is essentially correct. In this case, our reference is as the p[lane is flying straight and level on its longitudinal axis. Just to be certain, that line would be perlendicular to the hinge line of the rudder/fin and also perpendicular to the vertical axis of the rear cabin bulkhead.

That is how the plan is drawn and that is how the plane is built. When you see the plane in that orientation, the correct incidences, as designed, are those specificed in the Tower Hobbies description.

The die cut sides are set up to set these figures whether you like it or not. You'd need to change those shapes to get something different.

If your plane is set up with +2 degrees on the wing and -3.5 degrees on the horizontal stab, it does not meet the design spec., no matter what reference line you are using.

My suggestion is build according to plan. Then fly and enjoy your Super Decathlon.

Zor

do335a,

It all looks fine.

When flying straightthe decalagebeing 1.5 degreesthe power setting determines if it is level or climbing or descending.

Of course a steady speed will result with the elevator in line with the stab.
It can be trimmed for a different speed and a climb or descent depending on the power setting at the wish of the pilot.

I nearly never glued my stabs. I bolt them on so that I can change the decalage for experimental purpose.

Zor

WILDCRASHWILLY

Hi Guys,

I have not worked on the Decath much in the last couple months due to work and pretty flying weather when I was off work. However, I worked on it yesterday and today recovering the plane where I had removed all the green Monocoat. It is now covered with blue Ultracoat and needless to say, I'm much happier with the results. I have applied the Ultracoat with a minimum of heat so I have plenty of temp range to provide additional shrinking later if needed. I was burnt out with the previous covering but I'm happy to say, the build is starting to be a pleasure for me again. I will try to get a white starburst pattern on tomorrow as I plan to take a day of vacation and with the predicted 20 MPH winds I won't be flying. What can I say guys, I'm okay up to ten or twelve but, at twenty I wimp out, especially with the cooler temps.

WILDCRASHWILLY

Put the starburst pattern on the wing and tail stab this afternoon. will try to put the rudder stab starburst on tomorrow night. I have them cut out of the Ultracoat so it shouldn't take too long.

BTW: I hope evryone in the northeast remains safe during Hurricane Sandy.

nh4clo4

My Feedback: (33)

Looking' really good Bill. How soon before the maiden?

WILDCRASHWILLY

Thanks Ed,

Just guessing, depends on my travel schedule from work and the weather. On weekends that are pretty, I try to fly as my flying season is rapidly winding down. If the weather is poor the next two weekends, I might be able to maiden by Nov 17th. I still have to prep & paint the cowl, install proper cooling baffleing in the cowl, install the windshield, hook all my Ele, rud, Ail. linkages, and spend a little time test running the ZDZ40 .

WILDCRASHWILLY

Covered the wing struts and epoxied the studs into the end of the wing struts today. Also, connected and adjusted the elevator and rudder servos along with the tail wheel cables. Used 4-40 rods on the elevator servos. Installed pull - pull cables on the rudder. Took some measurements for the cowl to engine baffles. If all goes well, I'll install the wing servos tomorrow night.

Took some pictures today but they don't look much different from what I have already posted so I didn't show them tonight.

Have a good week everyone,

drube

Hi guys, great thread with lots of info. I have an SD on the way and was wondering how well a DLE 30 would fly it. I see it's in the middle of the recomended range. Also I was looking to use Solartex with latex paint any one go that rout?

Thanks

RCVFR

My Feedback: (7)

The DLE 30 should be an excellent match up. Mine was powered with a Zenoah G38. I also used latex paint, but over SIG Koverall. The Solartex would also be a good choice.

drube

Great thanks! I did go back through the thread, nice looking plane you have!

drube

RCVFR, Did you clearcoat after painting? How well does the latex hold up to gas?

mikem99

Hey drube,
Welcome to the thread.
My Dynaflite SD is covered with Coverite fabric, Super Coverite,(no longer available). and painted with latex. Because I didn’t prime it, I had a tough time to get the yellow to cover, (I used 3 coats). It came out kind of on the heavy side but I have an old Quadra 42 in it for power and it flies very well to my expectations. To me this is the important part of the project; “Does it perform to my expectations?� These are not real scale models, nor are they 3D, but they do fly well and look nice in the air.
Latex paint stands up very well to gasoline, but I clear coat mine as it makes the airplane easier to clean and less prone to shop-rash.

Have fun building it and enjoy flying it.

All the best

Mike

drube

Thanks Mike. I was wondering how many coats it would take to fill the weave and I do plan on clearcoating it. I think I read somewhere that the full scale plane is covered in fabric?
Thanks for the info.

mikem99

Hi drube

Yes the real Decathlon has fabric covering.

As to Solartex and the weave, I have never used Solartex but I have seen some nice covering jobs done with it. You may want to experiment with painting to fill the weave. My latest project is a AMR Eclipse that I primed the super coverite with rattle can primer and then used regular house paint latex, two coats and the weave was filled, then clear coated.
My next project is a Unionville 8’ Beaver and I’m thinking that I will cover it with Sig Coverall. I’m not sure about filing the open weave of the coverall but I’ll experiment a bit first.

All the best

Mike

drube

Thanks again Mike.

flyrcboy

Does anyone know how Solartex compares to Monokote and other heat shrink covering when it comes to weight? Also what type of paint should be used on solartex to withstand glow fuel?

WILDCRASHWILLY

Drube,
I agree with RCVFR that the 30 should be a great match. I used a ZDZ 40 but that's overkill. Also, it make's it difficult finding a prop for ground Clearance. It forces me to use a three blade prop to keep the diameter down. I'm using a three blade 18 X 10 Biela.
If you've read the thread, you know that I had issues with the monocoat. I wished I had tried the coverite or some other brand of fabrick.

I hope you have a good build. Even though I had a few issues, it's. been enjoyable overall. I went to put my spinner on the other night and realized it was made for a glow. I have ordered a trueturn with a flat back which should fix the issue. Working on the cowl finish and tail wires this weekend so I'm finally about to finish this project.

mikem99

Flyrcboy,

Monokote weighs in at .2 oz./sq.ft

Solartex weighs in at .34 oz/sq.ft

Therefore, Solartex is 1.7 times heavier than Monokote.

But remember we are comparing shiny apples (Solartex) to dried prunes (Monokote)

This is just my opinion, many others will think otherwise

All the best


Mike

drube

Thanks Bill, I'm on page 38 of this thread, i still have a lot to read. I have another project going on over at my friend's house (Extra 230), so i'll have more time to work on the SD at home. It's due to be here Tuesday and I can't wait to start. This will be my first Gasser and Hi winged plane.

drube

Hi guys,
I'm getting ready to build the wings but noticed on the plans the Right wing has a W4 before the wing tip but the Left wing doesn't show a W4 it stops at W6. Is this correct? What am I supposed to do here?
Thanks

do335a

It's been a few years since I did mine and no longer have the plans. However, I did not notice or recall any problem with the plan layout for the wing. SOme items were hard to specifically locate on each panel, but no big errors.

I found the wings very easy to build.

Essentially, you build two wings, identical mirror image of each other. So it doesn't really matter what you call the part in one wing panel compared to the identical part at the same location in the other panel. Just be certain that they are the same parts in the same respective locations.

Someone else who still has the plans should be able to verify this.

drube

Thanks 335, The left wing is different to where it doesn't show rib w4 and wing tip location. I have no guide that shows where to put the last rib before the wing tip.


I think I figured it out. There's dotted lines on each wing plan that I need to line up to finish the left wing.

drube

Another question.. Is the top wing spar level across the hole wing or is it supposed to have a dip in it towards the root starting at w3?

beepee

Dead level by my memory.

Bedford