Outline · [ Standard ] · Linear+ It's the WILD HAWK

[Mooshu_Beef]

OK guys, so this is my current project: The Wild Hawk!

I got this used. Since I've gotten it I've cut out the ailerons, stiffened the fuse, put on a brushless motor, replaced the servos for rudder and elevator, changed the rudder control to a carbon rod and servo-ed up the ailerons

I am going to put a keychain cam to record the flights.








Cover over the servos.


Velcro inbetween the wings so they don't rip apart in the sky

Maiden tomorrow! Hopefully

This post has been edited by Mooshu_Beef: Mar 5 2010, 11:28 PM

[Mooshu_Beef]

The maiden today wasn't super successful. As with all my other flying experiences thus far the plane wasn't in the air for a very long time. It was windier than I thought it would be but I walked all the way to the campus soccer fields and I was GOING to fly this thing, haha!

There was just too much wind for me to get the plane to fly stable. It tip stalled every time I tried to correct the plane. There was just wind swirling and it wasn't very consistent.

Half of the elevator hinges snapped off and the entire rudder snapped off. I also stripped the rudder servo D: (plastic gear anyway).

I gotta redo the hinges and pick a better day to fly . I'll post pictures later.

[Mooshu_Beef]

http://www.youtube.com/watch?v=l4HC1aIbVnc

I tried flying it again today. It was MUCH more calm. It's clear that all my planes like to roll left.

Is it possible there is too much weight too high on the plane? It just didn't feel stable like the vids tend to show of other wild hawks.



The left side broke off. I had to cut the 45 degree angle so I could hinge it with strapping tape.


Spy keychain camera. I put some foam over the microphone to try to reduce wind noise. Dunno if it works yet since the plane hasn't been in the air that long and I keep forgetting to turn it on .



Before...



After

[baratacus]

I'm sure that your plane is probably lighter on top with the brushless motor instead of the speed 400 motor that comes stock in those. could be a number of things causing the roll. The one that comes immediately to mind is your aeleron trim. You should be able to adjust for roll if it's a consistant rate. If you notice it more under acceleration then your problem may be torque spin or the airframe could be twisting under load. Have you changed out the prop for one with more pitch? Did you reinforce the fuselage? With the long narrow fuse on these, It helps to have reinforcing allong the aft fuse to the tail. Are your control rods to the rudder and elevators free of resistance and the throws limited so they don't twist up the fuselage? are your wings perfectly straight with one another. No play in them so that they can twist and cause roll?

Ok I was checking your album out and I saw the aelerons. You have them hinged on the top of the wing with tape. The leading edge of the control surface is squared off so that it acts as an airbrake on the bottom while you are trying to deflect air off the top. This is going to create some strange flight characteristics. The control surface needs to be hinged on the center line, not the top or the bottom. The leading edge of the control surface needs to be rounded so that it doesn't act like a drag chute when it's exposed durring deflection. Usually a wings trailing edge is tapered pretty thin so it isn't a big issue, but you got a nice fat wing with a sharp taper at the end. Your aelerons are cut up to that thick part of the wing so the leading edge is going to be more critical.

This post has been edited by baratacus: Mar 7 2010, 08:32 PM

[Mooshu_Beef]

Ooh I see, so taper the sharp edges on the bottom of the wing? Cause one side is a 90 degree angle and the other is the 45 degree ish. That makes sense...

It'll look more like two curves that meet after I am done but that's fine right?

I've determined also on another forum that my weight balance wasn't forward enough too. Go figure

[baratacus]

the trailing edge of the cutout in the wing doesn't need to be tapered, but the aileron piece that fits in the cutout needs it's leading edge tapered or rounded instead of squared off. This allows the aileron to rotate in the cutout allong it's center plane, and gives it freedom to move up and down without rubbing on anything.

[Mooshu_Beef]

Thanks Barat, I'll do that eventually

So I took out the wooden dowel that was the motor mount... That thing was 1/2 an oz and I replaced it with a piece of wooden ruler that doesn't register on my crude spring scale. This allowed me to also move the motor forward slightly and now I don't have to counterbalance to get the right CG.



Originally with that wooden dowel motor mount the plane needed 2 oz of counterweight on the nose to get the CG just past the midway point on the spar. Now with these small adjustments the CG is right at the midway point of the spar.



It's a little crude, I know. It is decently strong though, surprisingly.

I look to fly this again this week after the rain passes. Hopefully this time I remember to turn on the camera on the nose of the plane