ORIGINAL: Zpat
ORIGINAL: BMatthews
You can try adding a rib bay to each wing but really the important issue is that the model is just plain too heavy. I'd cut your loses and move on to building a new model with more careful attention being paid to reducing the overall weight down to around 24 or less oz.
Your right.
This is an electric airplane. Glow engines are just too heavy for it.
WOW! Have the tables ever turned! A few years ago converting a glow model to electric was seen as basically slinging an anvil of extra motor and battery weight round the model's neck. Now we've got folks saying that glow is too heavy to let an electric model perform well. I never thought I'd see the day....
Things have come a long way and these days it's quite possible that a brushless motor, prop, battery pack and ESC totals the same or a bit less than a glow engine, prop, muffler, fuel tank, average fuel load and the throttle servo to run it all. Who'd have thought this would ever come to pass. Then add on the extra structural mass to absorb the engine's vibrations as opposed to the silky smooth torque from a motor and you've got a case were it's entirely possible for the engine powered option to actually be heavier overall.
Sorry Zpat, this isn't an answer for you but just a momentary modeling epiphany on my part.