I think we are saying the same thing as far as the thrust agles, you're saying down thrust for a forward pointed engine(the THRUST is actually going up to the rear) and I'm saying up thrust for a rear facing engine(the THRUST is actually going up to the rear).

"With the prop behind the CG I think the side thrust needs to be intoward the center of the plane to offset the single engine turning force. ( Left engine out, right engine pulls the right side of plane to turn left- so some left offset will push the rear of the plane to the left to correct the left turn - ???) I have mounted the engines so they can easily be adjusted so if the plane lasts I can experiment. I would like to have it right the first time though. "

Are we doing the same thing here also? When you say left offset above are you talking the back of the motor which is towards the front of the airplane being offset to the left? If so, then yes that's what I mean too.

"I have mounted a single 16 oz. tank ahead of the engine plate with a single pickup of 3/16" diameter tubing that T's as it comes out of the tank. The two equal length 1/8" lines then go to the carbs. Both exhaust taps for pressure will feed the tank with check valves so one engine running will not bleed pressure out the other's exhaust. I hope I don't have to use a pump, but we'll see. "

I think two smaller individual tanks is better but if you use one I would put two seperate clunks into the tank, one for each engine. The pressure check valves sounds good in theory...

"As far as an emotional investment, every plane I launch has some, but the experiment and learning process is the real thing. "

I have a bunch of my designs that have either never flown or I was lucky to fly once or twice and moved on so I see what you're saying. That said, having a proof of concept model or intermediate can help iron out small problems or improve skills that when combined together on a new project could overwhelm you. There have been many times I wish I had done so that I could have fixed a problem before I ever made it.

"Please think about the thrust offset issue. I want to get it as close as I can for the first flight. "

This is pretty critical, do you think we're looking at it the same but from different angles? I do.

Another thought is the horizontal plate set up. Two engines espesially high rpm one's reverberate off each other, I recommend that you bench test the plate set up before you put it on the airplane to make sure you have enough torsional stiffness each each direction. This would also be a great chance to test your fuel delivery setup.

Ed, could we have been looking at the thrust angles the same but from differing directions too?
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