I just finished telling someone how to electrify an Easy Sport 40 and thought I could share with you guys:
My Easy Sport flies great!!!
I use an Astroflight 40 with the standard AstroFlight gearbox, running a 12-8 prop.
At full throttle current is about 25 amps with a time at full of five minutes with Sanyo RC2000 cells. I usually get nine minutes ( one minute of full for take off and climb, the rest half throttle) of flight time.
I use 21 Sanyo RC2000 cells that I put in through the fuel tank access hatch. I wish I had a digital camera or scanner to take a picture of the battery tray and show you how I modified the interior of the fuselage. I will try to explain to the best of my ability.
The servo tray is at the rear of the fuselage with the first opening for the throttle servo. The two in the back are for the elevator and the rudder. Normally the front of the tray which is the throttle servo butts right up to where the landing gear block is so I removed the space for the throttle servo and had a perfect space for the receiver.
From the landing gear block I ran a lite-ply tray that leads to the fuel tank access hatch. Back at the landing gear block I put a vertical piece of liteply to stop the battery pack.
I put Velcro on the very front of the tray and on the vertical part that keeps the pack from sliding too far back. The pack can be slid through the fuel tank hatch to the tray then slid down until it reaches the stop and the Velcro secures it in place. I ended up using about 2 and a half ounces of tail weight which I could have compensated for if I had known when I started to build my plane.
I would either buy a Maxim motor which is lighter than the Astroflight, or I would modify the wing to accept two aileron servos so the pack could be slid farther back without binding with the servo in the center of the wing. My Easy Sport has plenty of power for aerobatics and flies terrifically.
The weight is 7.5 pounds with a wing loading of 23 ounces per square foot.