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Jun 21, 2016, 02:33 AM
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Great Planes Siren warmliner

Got the airframe for free at Baylands Park , with a broken wing, it needed some TLC to get in flying condition.

Many thanks , anonymous donor !

It has a 300 W in-runner motor, Kv =3900 RPM / V.
So, it operates in the ballpark of high 30 k RPM.
The propeller is a thin 5 in x 4 in

Battery LiPo 3S, 30C, 2200 mAh.
Wing span is 80 in, wing root chord is 7 in , wing area is 3.4 sqft.
All Up Weight is 45.9 oz, wing loading is 13.5 oz / sqft.
CG still needs a bit of trimming, feels nose heavy ...
Notice in the second launch, the visit of my friend the hawk .

Flying at Lariat Canyon, Walnut Creek, CA.
Great Planes Siren ,T-tail warmliner , maiden flight - Movie (2 min 36 sec)

Great Planes Siren, T-Tail warmliner, onboard video (1 min 51 sec)
Last edited by JureZ; Sep 07, 2016 at 12:26 AM.
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Jul 05, 2016, 12:51 AM
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Replaced the inrunner motor I tried earlier , now with an E-Flite Power 10 , with Kv = 1100 RPM/V , 450 Watt.
Using a 10x7 APC propeller, and 3S LiPo 2200 mAh battery.

It is much quieter now than with the in-runner with Kv=3900 , and the noisy 5x4 propeller spinning at about 35K RPM.

Siren , new motor , July 4th 2016 Movie (1 min 48 sec)
Last edited by JureZ; Sep 06, 2016 at 07:39 AM.
Sep 04, 2016, 04:48 AM
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flying again, after some wing repairs ...
The E-Flite Power 10 motor shaft was pushed back (following the instructions on the manual page) ,
to reverse the prop adapter location.
Now the motor is exposed to free air.

Siren at Shell Ridge, Movie. (1 min 48 sec)
Last edited by JureZ; Sep 06, 2016 at 07:38 AM.
Sep 11, 2016, 07:27 PM
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GP Siren Spoilerons

one more configuration change:

in order to make landings a reasonable affair, programmed the two ailerons as spoilerons. Using the Gear switch , added a mix for each surface, with up deflection of about 30 degrees.

much better !!!
Oct 17, 2016, 05:05 AM
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now with APC 11x8 , folding.

GP Siren - Oct 16th 2016 - Moraga - Movie (2 min 15 sec)

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