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PurgatorY
07-29-2007, 07:14 PM
Well, I dragged the plane out to the TEMAC field this afternoon, and Glenn and President Michael got test flights to get the airframe sorted out. THe left-hand elevon servoe got shifted forward 1/16th of an inch to ensure a constant right-turn against the roll induced by the 8-inch prop.

Weight: 13.5 ounces
Wingspan: 27 inches
Length: 39 inches
Motor: Dualsky XM2826CA-15
Prop: GWS 8x4.5
ESC REdcon 12amp
Battery: Dualsky 3s1p 1320mah

Glenn took the first flight and got the ailerons and elevator pretty well sorted out then landed it so I could make adjustments. Michael took the second flight and suggested shifting the left-hand aileron to give a right turn.

Both flights were with me holding the top of the airframe and then giving it a gentle toss. Third flight had Michael giving me the Tx and saying "go for it!"

I quickly found out that this plane is set up for a park flyer and is not the most sprightly thing in the world. My first landing was a lawn-dart that stayed there due to the CF strip spine between the two wing halves. A gentle pull out of the ground, checks for damage, suggestions for putting an EPP nose on, and Michael saying "well? It's a park flyer!"

One more flight had me on the sticks from start to end. Literally, full throttle to power up, gentle toss up at about 45 degrees, and the plane gently settling and then pulling up and away, tracking like it was on rails. Out to about 200 feet in altitude and then turning to the left to bring it around.

Left turns are easy, rights are harder for some reason. Have to keep the speed down to keep it from going verttical -- I let it do that and then had to roll out of the top at about 300 feet. Most flying was done at half to two-thirds.

Have to keep reminding myself to keep about 1/3 throttle during approaches as I tended to stal about four feet off of the deck in a traditional power/elevator approach.

Plane is slow to respond to inputs and this could be due to the lack of stiffness in the wing structure (no CF rods or strips in the wings).

However, it sure impressed the heck (hatch-e-double-hockey-sticks according to one person) and I've been asked for plans. Basically, it's the 1.24th aerodynamic study planset top and side views cut into halves, plus additional engine bumps to add stiffness at the back end and two braces around the lipoly pack opening.

PurgatorY
07-30-2007, 12:37 PM
Shot of one of the lower "high-speed" passes.....
http://www.temac.ca/2007-07-29-08.jpg

Mark DiMonte
09-19-2007, 05:57 AM
God I love the Profile of that plane in the air. I had problems turning with my arrow as well. Flight testing showed the need for a slightly nose heavy plane. This allowed the nose to drop into the turn. What helped the most was the addition of rudder and mixing it to the ailerons. The plane really grooves. Keep flying.

PurgatorY
09-27-2007, 08:18 PM
Plane does not handle breezes well, let alone a stiff wind (20-30 MPH).

Released model and immediately went into left hand turn regardless of what I did.

Last flight had ground impact (belly-whopper) just after release which resulted in the motor being stripped off. Of course, the wind immediatley dies to dead calm.....

#2 already under way with CF tube in wing. Still too much flex in aileron (servo at inboard end) to make life happy for me.

If get similar flight, I'll shift to larger buit-up version using single Wemotec.

If #2 acts the same way

Tex Gehman
09-29-2007, 03:21 PM
Plane does not handle breezes well, let alone a stiff wind (20-30 MPH).

Released model and immediately went into left hand turn regardless of what I did.



Oddly, my built-up (Canadian kit) pusher did the same thing every launch. Immediate 90 degree left bank, but levelled itself very rapidly. Hmmm? I didn't like the flying characteristics at all, especially if there was any gusts.

PurgatorY
09-29-2007, 05:50 PM
I'm wondering if it's a torque roll problem resulting from being released, but then the first flying day (calm day) had no problems at all. Let it go and it would go straight out.

Getting started on the Mark II version (CF tube in wings), and should have it finished by next weekend. However, I figure that Thanksgiving will not be a flying occasion....

BTW, what was the bult-up Arrow that you wre flying? I can only think of three manufacturers of that size model -- Madrob's laser-cut design, Wings of Yesterday, and RTModels.

Tex Gehman
09-30-2007, 07:44 AM
BTW, what was the bult-up Arrow that you wre flying? I can only think of three manufacturers of that size model -- Madrob's laser-cut design, Wings of Yesterday, and RTModels.

It's MADROB's design. It went together very easily. Some wood was a bit light for purpose, but overall a delight to build. Nice looking model when completed and tiddlied up. Tex.

PurgatorY
10-01-2007, 07:14 AM
It is a nice design. Too bad that the kitter from Barrie seemed to make a muddle of things (webpage no longer up) plus Madrob had issues with the arrangement.

If Madrob gets the kit back in production again (he may have one or two short kits left), I may pick up one.

I'm going to do one more cruciform version and get on with other projects that have been piling up.

You should post pictures of your speed-bird on Madrob's construction thread that's soemwhere here -- check his id in the Members section followed by "all threads started by".

Have a good Thanksgiving weekend -- I'm going to be too busy to even think of flying.....