trimming the bird dog

[r wheatley]

I built the 900 series bird dog, and after much trimming ,and balance I flew it off my deck yesterday (deck is only 3' off the ground, any way I got a really smooth straight decending flight it actually landed on the wheels, distance was about 25 yards, now I need altitude , should i try down thrust or elevator adjustment or add trim tabs.
I would like to thank all you guys on here that share you knowledge and experience

ronnie

[WIDDOG]

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I’m not knowledgeable or experienced... I noticed you did not mention what you where using for rubber. The plan recommends 36 inches of 3/32 inch rubber. I’m guessing that what you’re using. I will read what the others say.

[Wildpig]

If you got a smooth, straight flight: don't mess with the elevator.
1.Mark the center of gravity location on the model. Keep the C.G. at this position from now on.
2. Install the rubber motor mentioned on the plans,36" by 3/32". Doubled over to make 4 strands.
Make sure your C.G. location is the same as before, adjust by adding or removing weight.
3. Add a downthrust shim. no more than 1/16" is my guess.
4. Lube the motor.
5. Stretch wind that thing about 300 turns.
You will need to make trim tab or rudder adjustments.
Let it fly.


(edited to add downthrust shim note 3. How could I forget that?)

[Phugoid]

How much does your model weigh, what rubber are you using and how many winds did you have on when you got your "powered glide"? Also was the flight "floaty" or more arrow like?

Andrew