Yeah, 40 seems underpowered, That does not mean that it wont fly, but will take alot of runway to get off the ground. Like Mr Buckner said, if there is a local club near you, have a seasoned pilot maiden it for you and give you insight on power, balance and overall flight characteristics. Of course if you decide to take off on your own, do search prior to flight for reviews, forum discussions, etc... you can find out alot by googling. You can find out alot about the engine and the plane in the compare products section under the user review tab at the top of this page. All that said, there is a pilot at our field that flies everything underpowered, makes him a better pilot he says, and he's probably right. Your engine placement sounds right on the money, down and right thrust, is what you want. What size and type of prop is on it? What size fuel tank? Rx Battery? get the plane up high, fly level at half throttle and release the sticks, trim then. keep it up high, level flight and cut the thotttle, see how it glides. That will give you an idea as to how it will react when landing. You'll have to do the search I mentioned before about landing, most warbird style planes have to be landed and little hot. Just be ready to go around if the approach doesn't look or feel right. If you get in to trouble chop the throttle and let go of the sticks, if you're high enough the plane should level out, then take control again. Stay three mistakes high for the first few flights. If you have a sim use it until you are comfortable. Not much else I can say except good luck!! and GO for IT!!