Thanks Bleary.

He's right though, the motor mount area is the weakest spot.

WingCommander,
Let me know how you make out. I may look into converting my launcher into a truck bed mount. Save dragging it all out to the field. Just put down the tailgate, stretch the bungee, and swoosh into the air.

GG~~Wow, I've influenced a real pro? I'm humbled...really. I've got ideas on how to modify my launcher to incorporate your suggestions. The keyring for sure. Then maybe braze two eyebolts (small ones) below the rails on each side out closer to the ends (depends on the length the bands will stretch), right up just an inch or less below the launch surface...not 4 inches below as the rubberbands are attached now...will produce the more linear pull. Then use TWO bands, one on each side tied into the keyring...twice the force at nearly level with the bottom of the bird...SWOOSH! I think it should work. Probably just before reaching the band attachment points, the keyring falls off and falls below the passing prop. Tahdah! I think your truck bed idea is a good one. Drawback that I also face is having to align the car or truck into the wind. Not rocket science and in my case where I fly in a farmers field, parking this way or that is not an issue. WC [sm=bananahead.gif]

Kinda like a mobile SAM launcher.

Bleary, thanks for the great information. I had not considered adding epoxy to the channels on the motor mount but will most certainly do this! I agree, tie wraps are a cheap and easy way to add additional reinforcement. I am using one now. I also added a heavy rubber band that loops around the back of the motor and then over the tie wrap underneath. Just another failsafe addition.

RS

WC, I finally checked the motor alignment and glad I did! The line terminated just below the bottom edge of the nose cone! It was a wonder that it would fly at all. I corrected the alignment using a piece of an old broken motor mount (don't thrown the old ones away, they come in handy!) Bad wind today so no chance to check it out[]. Anyway, will let you know how it goes. Hope all the repairs to the nose area hold!

RS~~Don't thank me, thank Glacier Girl. He taught me how to align it. I'm still looking for a way to align it dynamically (like with power on to see if body is forced at an up or down angle). I may be able to do that with my launcher when I max the power just befoe launch. The last time I tried it, the tail was pushed up a lot and the bird went nose dive right off the end of the launcher. I've since adjusted the motor tilt and hopefully it won't happen. I just think the dynamic alignment will be more accurate in the end. I'd say the yardstick method is a good starting point though. We'll see. WC[sm=bananahead.gif]

You will find motor angle and proper CG are probably the two most important things on the Stryker when you want to go fast, and have it perform well.
A tip I picked up somewhere. The design of the wing of the Stryker is a lifting body. that's why they glide so well. As speed increases, so does the lift effect. The faster you go the more she want's to climb. There in lies a problem. To combat the lift you need to keep dialing in more down elevon, this pushes the nose down but adds drag, that slows you down. [:@]
How do you fix it? Well you can go the route I went on my fastest one. I redesigned the wing to fully symmetrical. Works great for speed but looses a lot of lift, not good for slow flight.
Here's where the tip comes in. Set the angle on the motor to push the nose down, the more the better. At launch and low speeds you can trim the ailerons up to compensate, you're not going as fast so drag is not a problem. Now the faster you go, the harder the motor is pushing down on the nose as the lift from the wing is trying to push it up. They cancel themselves out. And as you are not applying down elevon, there is no additional drag being added.

GG~~Another thanks. I may well try this.... in time. Right now, I'd prefer the lift and drag to perfect the launch mechanism. I had already noted the major amount of lift as it gains speed and had had to trim it way down as a result. That trim down, motor alignment pushing the nose down, and the lack of airspeed off my launcher resulted in a lot of belly-out COT's and bloody nosecones. Maybe when I get her launching, I'll become more concerned about speed. They certainly do glide nicely. Piece of cake to land. How did you make the wing symmetrical? And what, exactly, is the "proper" CG? WC[sm=bananahead.gif]

W/C
A lot of work on the wing, I took a slice out of the top of the wing and glassed it to the bottom, then resanded the entire wing to the symetrical shape.

CG is Center of Gravity.
On a Gen 1 fuselage it's around 6 1/2" from the trailing edge of the wing.
On Gen 2 and 3, 3 being the B version with hinge cut outs, it's marked in the hand grips.
Look for 2 little circles, one inside each grip. That's the CG point.

GG~~That's quite the project to make the wing symmetrical, unbelievable really. I knew CG meant center of gravity but you answered my question anyway. I have a gen3, B model Stryker. I think my CG is right on the money. The battery placement is everything on that I'd venture. WC [sm=bananahead.gif]

Yep the battery is moveable weight. Don't add weight to balance, move the pack.
I know this sound simple but some may be a little afraid to cut some faom. Go ahead and do it. Don't go adding weight to balance your bird. That's just more to slow her down.

One other thing, check your balance side to side. One finger under the tip of the nose and one under the prop. She should balance out level. If not she's going to fly with a built in turn. The heavy wing will drop and you will be in a constant turn you have to trim out to correct. And adding trim is adding drag.

GG~~Aye Aye Sir. Will do. WC [sm=thumbup.gif]