Hi all! I have been kind of out of the loop for a while, Just some life changes making it tough. I thought I would share my 4 engine "bomber" scratch build with you guys and share the maiden test flight. A little back story, this started out with my oldest son wanting to do a multi engine/motor plane before he was married and we gathered the parts and set on the Flitetest P-51 mustang wing as our jump off point for the plane. We made the wing following the basic design but stretched it to 58" and that is where it stopped, he got engaged and busy with his bride to be then married and he left it all set here. So this winter he said do what you want with the stuff. I decided to finish what we started! I designed the fuselage from scratch after looking at bombers and other aircraft for hours.
Here is what I drafted up in windows paint.
- bomber side LG.png (40.7 KiB) Viewed 5758 times
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I started to built this monster and all I can say is more motors mean more wire, more weight, more headaches. I mounted the esc's in a vertical rack system to make it easy to connect the motor wires coming from the wing access port.
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- motor wires.jpg (130.23 KiB) Viewed 5758 times
To keep the Rx working I incorporated a UBEC running off a separate 1000mAh LiPo that has an external switch and voltmeter.
- electronics side.jpg (118.5 KiB) Viewed 5758 times
The motors are counter rotating of course and run off 2 separate 2200mAh batteries the outboard engines are together and the inboard are together that way if I have a failure of a battery or esc I don't lose all or one side of the plane. From this top view you can see the 2 square holes for the batteries.
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Some of the specs.
58" wingspan, wing cord tapers from 10" to 5" center to tip.
Fuse length 40".
(4) 2822 1100Kv motors swinging 7x5 props,
(4)20 amp esc's with bec circuit disconnected
(6)10 gram servos, 2 aileron, 2 flaps, 1 elevator and 1 rudder.
3 batteries (2) 2200 3s, (1) 1000 3s (1) UBEC 5 volt 3 Amp output
Aluminium landing gear with 2.75" dia. tires Steerable tail wheel
All up weight is 3.48 lbs
The engines are producing 3.0 Lbs of static thrust according to my redneck thrust tester.
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Bottom view with yard stick for size reference.
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Side view
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Well that's quite a lot to take in! I have flow a maiden flight and it was not too good! Major miscalculation on the CG and too much control surface throw and that might have been exaggerated by the tail heavy CG.
http://www.youtube.com/watch?v=0WZfytUbMmw
More work to do so Bomber 2.0 soon
