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Old 05-16-2018, 12:21 PM
  #418  
David Bathe
 
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Wow.. there are some nice tigers here and VincentJ, marvelous woodworking skills. Beautiful to see.
Just a heads up for setting up incidences for further projects.
A wing needs a positive incidence to fly, even our multi-billion dollar F3A aircraft are set up with 0.5deg positive.
If you set the wing at zero, the first thing you'll have to add is some up trim, thus moving the tail down and adding a positive incidence to the wing.
Big deal??? well yeah because you've now changed your tail and motor incidences.
Normal set up for our normal two blade prop/mono wing aircraft has been and basically still is:
Tail: 0 deg
Wing: 0.5 positive.
Motor: 3 deg right, 1 deg negative down.
CG: 25 - 27% MAC tune to personal taste.

There are those out there that believe there exists such a thing as a neutral 0-0-0 set up.
There isn't. You might build it that way, and it'll fly... but as mentioned, you'll either add up trim (to lower the tail and create the positive wing incidence) or have the CG set so far back that the aircraft flys tail-low, thus the positive wing incidence. This is fine if you're flying lightweight models close and slow (indoor foamies 3D aerobatics etc) but doesn't work well when flying out there and big. It's up to you but for general flying, just build it in at the beginning.

BTW, An aircraft set up with a 0-0 motor isn't pleasant to fly. If you've been struggling to get your airplane to fly some nice easy aerobatics without squiring out... this is one of the main reasons, the easiest to fix and the one that gives the pilot the most instant gratification and immediate payback. Some years ago many of us when the Chip Hyde route and eliminated right trust and instead used a right rudder mix/curve. Been there done that... we're back to old fashion right trust;-)

Not trying to cause an argument, everyone one has there own personal take on this but this tends to be the ISOnorm in the pattern/competition community.