The only mods to the original are 1) doubled the step to about 3/8 inch. I've found that on the micros you need more step because of water adhession. I have a micro P-82 built from two PZ P-51s on floats. 2) raised the motor a 1/4 inch for prop clearance. Otherwise standard setup. Motor is a APO5 3000kv,prop GWS 4.5x3, 7a ESC, 2s 350mah, AR6400 rcvr block up in the tail and two 1.5g spektrum servos for the ailerons. This was just a quick and dirty spy cam photo cause I was too lazy to get the good camera. Hopefully more tomorrow.
Thanx Larry, you turned me on to it. Very good flight characteristics but does not like inverted. Is the big one that way? A lot of elevator to keep the nose up, and I mean a lot. Also significant pitch changes with speed, not power but speed pitch changes. Nice addition to my water toys.
Thats mainly a CG issue. Im flying the big one way behind where Steve recomended the cg to be. I tend to like my models to be pretty close to neutral CG wise. That can make for a sensitive elevator but it really improves over all handling - especially the issues you are talking about.
If you do move the cg back, be prepared to move the step back as well or you can get severe porposing when landing at speed. if you remember in my water video that first landing at speed had multiple bounces. Thats due to the cg being well behind the step. When you hit the water, the weight pushes the tail down and causes the pitch up. Having the step further back reduces that or eliminiates it.
its not an issue if your flying the stock CG point - only if you move it back.
IIRC, I ended up about 4" to 5" behind where Steve recomended the CG to be. Thats equal to 2" behind on the original drawing. For your size - if Im doing the math correctly - that would be about 7/8" to maybe 1" behind the "stock" position if you started where Steve said to start.
I just measured and I moved the step back 4" on the XXL and I was going to move it back another 1/2" but didnt get around to it.
You need the step to be just slightly ahead of the cg. To far forward of the CG causes the porposing and to far aft makes it harder to rotate and harder maintain straight lines on the water or grass at speed. Its just like having the main wheels on a tail dragger in the wrong position.
It flys so well upright I don't what to change it. Flew two flights in a Gym last night at 1/3 throttle, great low speed handling. Generally, I've found on the little ones that you need the extra stability due to gust/bumpy air. I am right at the suggested cg. I will try an experiment, move it back and check inverted behavior and elevator sensitivity.
Love it! It's so darn cute! Flys great!
I didn't hear, does it have an elevator, or elevons?
I've had the original kit version flying for over a year, and love it. I think I need to build that one.
Can you give us a snap shot of your plans, with dimensions if possible?
Thanx. It does fly great even at low speed in a Gym. I have ailerons and elevator separate but will probably play with elevons and elevator per Larry's comments. Also I'll play with CG. But make no mistake this flys well as is but I'm an old pattern pilot and love being upside down so I will work to make that happen.
Larry, on my Sea Dart thread sent me a link to plans for the Polaris. I took this and scaled them down to a 13 inch wingspan. Only changes were to make the step 3/8" and to raise the motor pod 1/4 to a half inch to allow prop clearance. I mounted the AR6400 flat to the bottom of the stab and boxed it in after wiring and linkage connections. I mounted 2 1.5g servos flat to the wing under the fuse top. It takes 7 Chevy's containers to build. You can get one good flat 6" by 6" square out of each container. My prop, as indicated is a 4.5x3 GWS but I forgot to add that I cut it down to 3.75 inches. So it is a 3.75x3 prop. Best and good luck.
I'm thinking about getting the polaris for a sea plane. I saw one last week, and all the servos are buried in the foam. doesnt seem easy to get to servos, anyone rework this with hatches?
I've been flying my Polaris for 3 years, never needed to see the servo's.
I put in good 9gm servo's, hxt900's, $3 servo's from Hobby King. They are cheap in cost, but I've used over 50 of these servo's, and never had one fail. I've striped them in a crash, but never in flight.
Larry's right, it's a foam plane, easy to make a hatch latter if you need it.
Not a single drop of water has entered my Polaris. The only hatch I have is my battery hatch which I tape all seams when flying off of water. The only other openings are the push rod guides, which I fill with grease to keep the water out.