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Old Feb 21, 2013, 09:31 AM
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Si Goodchild's Avatar
Lincolnshire, UK
Joined Oct 2009
522 Posts
I'm really enjoying this build - so fast! Inspiring stuff.

Si G
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Old Feb 21, 2013, 11:29 AM
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Joined Apr 2009
25 Posts
Thanks I only have a month and a half of spare time into it. At this point I am installing the 12 servos after that is done I have to finish the bodywork and glass it.
I wanted to wait on a build thread until I had a bunch of pics to show the progress.
Oh here are a couple of pics of the Ramtecs in their new home .
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Old Feb 22, 2013, 05:51 AM
Life begins at transition
Australia, VIC, Sale
Joined May 2007
3,593 Posts
Looks good! Love the airframe too, great lines, unique...
Can't wait to see it fly
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Old Jul 08, 2013, 10:35 AM
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Joined Apr 2009
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Got the airframe done and under my predicted weight limit. It weighed 19.2 pounds ready to fly before primer panel lines and paint and now it weighs in at 25 pounds ready to fly Im going to springfield for the maiden on thursday wish me luck.
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Old Jul 08, 2013, 11:11 AM
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Joined Apr 2009
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Here is a pic on its gear for the first time all surfaces have been glassed at this point as well as the fuselage. Ready for primer and panel lines
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Old Jul 08, 2013, 11:42 AM
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Joined Apr 2009
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Ok here are some power evaulations. My intakes are 100% FSA, they are twin orientation and seperate from each other so no power robbing from one side to the other. The fan units are at the rear of the fuselage to follow the rules of efficency but there has to be a battery left in the nose to sit on its gear its tail heavy without the batteries in the nose. The tailcones are reduced to 80% FSA and is 10 inches long.

There are bullit connectors attached to 10 gauge wire with capacitors attached to protect the esc's from voltage spikes. Castle 110amp speed controllers to the motors and the rest is as follows.\

6s per motor 2520 watts per side @ 6 pounds of thrust
5040 total watts 262 watts per pound total 12 total pounds of thrust

9s 3780 watts per motor ,7560 total watts. 393.75 total watts per pound. 18 pounds of total thrust.

I can handle 12s but Im looking for efficency and I dont wanna over power the airframe on the first try I plan on doing a few test hops before commiting to a full circuit .As well as doing several battery temperature and motor and esc temperature analysis to determine if the setup will be efficent.
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Old Jul 08, 2013, 12:04 PM
Do it Right, the first time!
CoolerByTheLake's Avatar
United States, MN, Hermantown
Joined Dec 2008
5,659 Posts
What fan/motor combo are you using?
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Old Jul 08, 2013, 01:49 PM
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Joined Apr 2009
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Ramtec fans little screamers extreme scream motors the gold ones
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Old Jul 09, 2013, 06:26 PM
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Out of the paint booth ready for the maiden flight 25 pounds on the nose ready to fly
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Old Jul 09, 2013, 08:31 PM
EDF rules... :)
AirX's Avatar
Joined Nov 1999
13,639 Posts
Great job, good luck with the maiden.

Eric B.
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Old Jul 09, 2013, 10:38 PM
DELTAS RULE
corsair nut's Avatar
tehachapi, CA
Joined Jan 2006
22,444 Posts
Man...thats going to be a rocket! It looks awesome!
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Old Jul 13, 2013, 07:28 AM
Fly more Foam
sam51401's Avatar
United States, IN, Sellersburg
Joined Jun 2004
983 Posts
John!!!!!! Maiden report or was the wind still cross the runway Thursday evening?????

I have known John for some time and i ran across him and the Su47 at KY Jets thursday. Vary nice scratch build plane and light, very light for the size. We talked in length about how he built it and the ideas he used to arrive at this. I had to leave but hope the maiden went well.
He did say it was going to be baby steps at first, few high speed taxis and short lift offs or jump and goes!!! to see how it would react. He has plans to leave the canards fixed for the initial trials so if it did get down the runway, i hope there might be some video or at least some pics.
Look forward to hearing how it went John.
If you didnt get it in the air then please call me and maybe we can go to Bills strip and i will video it for you to post.
Sam
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Old Jul 15, 2013, 06:30 PM
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Joined Apr 2009
25 Posts
Well it can fly !!! I got it off the ground one time for about 80 feet after a 300 foot roll t the local field Sunday and when it broke ground it was out of trim on roll axis I sat it down and am planning on a full test flight this weekend power is good and it feels fine with just elevators and I have the ability to use the canards with a switch so they can be shut off or turned on when needed .
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