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Old Nov 22, 2012, 02:17 AM
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Tomahawk's Avatar
Southern Ontario, Canada
Joined Nov 2001
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I have been pushing to finish the Falcon in the last two evenings. Anyone living in Ontario knows we have been having a period of warm weather with little wind and I wanted to maiden the Falcon.

I added some tail skids made out of vinyl siding and finished the electronic installation. As you can see in the pictures the battery and esc are sitting on a tray on top of the servos. Most of the components are as far forward in the fuselage as possible.

I weighed the finished Falcon at this time and it came out to 55.9ozs or 3.49lbs. The original weight of the free flight Falcon was quoted at 40 ozs or 2.5lbs. I came out a pound over.

Time to set the cg. Well, this bird has decided to throw me another problem. As it stands, it is tail heavy or the cg is setting 2" behind the recommended location. Only adding weight to see how much would be needed to move the cg to the recommended location, I am looking at a 1.25lbs. Oooooo. not good!
I feel adding weight to counter the cg problem is not the way to go.
I am going to remove the cowl and extend the motor forward to see if I can compensate that way. Maybe along with one of those heavy prop nuts.
Anyway, because of the cg issue, the maiden didn't happen.

Chris
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Old Nov 22, 2012, 02:30 AM
I like real wooden aeroplanes!
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South-west France
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Ouch! I can well see why you wouldn't want to add that much weight especially when it is already on the heavy side. However, you definitely need to get that CG forward at least to the F/F position, so good luck in finding a solution. Just one more problem to overcome in a tricky build!
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Old Nov 22, 2012, 02:39 AM
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Australia, WA, Perth
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Balance was always going to be a problem with this design, lots of tail along way back and hardly any nose. Wasn't a problem with the original due to the weight of the ignition engine and all the bits that go with it, can you get that nice big battery up forward with the electric motor? Nice build though, Gary
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Old Nov 22, 2012, 03:06 AM
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Southern Ontario, Canada
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Quote:
Originally Posted by kkphantom View Post
Balance was always going to be a problem with this design, lots of tail along way back and hardly any nose. Wasn't a problem with the original due to the weight of the ignition engine and all the bits that go with it, can you get that nice big battery up forward with the electric motor? Nice build though, Gary
Can't see moving the battery. Not enough room forward in the cowl and the LG wires are located at the firewall. Right now I feel that moving the motor forward is my only option without major work on the fuselage. I would have to build a new cowl. I could see moving the ESC to the cowl as room would increase if the motor moves forward.

Chris
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Old Nov 25, 2012, 01:34 AM
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Southern Ontario, Canada
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While the snow was falling today, I did a little number crunching. With my pound of weight increase I was wondering if the wing loading was going to be an issue. Going back to the original build article, it was listed the Falcon should come out with a wing loading of 8 to 9.5 ozs/sq. ft. Wow. Even if I was building for freeflight I wonder if I could hit those numbers.

With my 1lb overweight I only come out at 13.5ozs/sq.ft. Seeing that number made me feel better as an average trainer is at 18ozs/sq.ft. My Falcon may not be a super soarer but it should still fly without issue even if I have to add a little more weight to balance it.

Chris
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Old Nov 29, 2012, 04:37 PM
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Still working on the CG issue.

Chris
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Old Nov 29, 2012, 05:04 PM
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Canada, ON, Caledonia
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Brillant...................... a true gem!!

Bill
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Old Nov 29, 2012, 05:43 PM
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Chris, That's absoluetely stunning .

Colin.
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Old Nov 30, 2012, 01:22 AM
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Thankyou for the compliments!

Chris
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Old Nov 30, 2012, 02:07 AM
I like real wooden aeroplanes!
Sundancer's Avatar
South-west France
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Gorgeous Chris, the finished result is a real tribute to all the effort you have put into it. Hope you can resolve the CG issues and good luck with the test flying when you do.
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Old Nov 30, 2012, 07:33 PM
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Valencia, CA
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Absolutely lovely!!! Very inspiring! Congratulations from a "twin rudder fan"!

You have solved every other problem so far, so I am looking to resolution of the CG issue and flight pictures.

Pete G
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Old Dec 04, 2012, 01:04 AM
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Southern Ontario, Canada
Joined Nov 2001
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Maiden VIDEO

The Falcon was maidened today

I had to remove the cowl and extend the motor mount. The battery and esc had to be slung under the mount. Also a Dubro heavy hub was added and the cg was finally moved to the correct location.

Probably the last maiden opportunity I had left before winter. Everything was done so I headed out to the field. I decided to maiden without a cowl.
The usual prep work and through range check. It was now or wait till spring.
Advanced the throttle and she easily lifted of the grass. Nice
Up to altitude, cut the throttle and it settled into the glide. It was nose heavy and decended quickly but tracked straight ahead. Tried a little trimming with the elevator. As the ground approach I again advanced the throttle to climb and things started to go south. I will let you watch the short video and see for youself. Gave myself a good scare!

Chris


Plecan Falcon Maiden (1 min 44 sec)
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Old Dec 04, 2012, 01:35 AM
I like real wooden aeroplanes!
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South-west France
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Yikes!!! indeed! Looks like there are one or two handling issues to sort out, but congratulations on getting that first flight out of the way, no doubt you will be planning adjustments! Nice looking flying field BTW.
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Old Dec 04, 2012, 02:19 AM
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Bet that set your pulse racing so where do you go from here with your trimming

Colin
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Old Dec 04, 2012, 01:19 PM
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Southern Ontario, Canada
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Quote:
Originally Posted by ColinNZ View Post
Bet that set your pulse racing so where do you go from here with your trimming

Colin
Good question Colin. Higher power and the Falcon seemed fine as you could see in the takeoff. The glide seemed fine and controllable. It was the the transition from glide when I added power. I have watched the video numerous times to try and figure out what happened. I was wondering if I was stalling the wing and needed more power when the climb began. I was running on instinct and noticed I kept reducing power to settle it down. When I punched the throttle before it almost hit the first time it seemed controllable but again I reduced the throttle and the wing started to rock again. I can't explain that last wing drop when it landed. I am also wondering about the torque from the prop.
If anyone wants to share an opinion, I welcome it.

-------------
Hi George, we fly from a sod farm. You are looking at the back quarter. We move around as the sod is taken off.

Chris
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