hey guys i took my trainner up again , the OS .40 LA fired up no problem , everything was a go for takeoff and there was no wind and about %85 humidity, so i fly it for 15 min , doing loops rolls andall of the regular things i do , my plane is sound but my .40 LA seems to lack power, almost like it was running rich , but it wasnt , dose any1 here know why my engine acted this way today? it was no biggie but its still a concern because i dont want to crash my plane do to a engine problem (if it even is one) , so did it run a little slower cuz of the humidity , or are they always underpowerd or what? it idles fine and all it just seems to lack alot, this is my 6th sucsessful flight, (without any help of a advanced pilot) i love this hobby and all , i just want to make sure this is normal and if its not what can i do to fix the problem.

Don

never owned an LA, but have read all over the place that they are notorious for being under powered.

Straight forward, yes, LA's lack power. They are built for ease of use. However, if your thinking that on that particular day your engine was lacking power, it may have something to do with the humidity, such as causing your engine to lean out and overheat and lose power.

Oh, I have a 7 pound LT-40 with a .40 LA for power.
Quit whinning.

Actually, a hot, humid day CAN cause your engine to run richer. Hot air is less dense than cold air (resulting in a higher fuel to air mixture), so if the engine was tuned on a day that was say 15 to 20 degrees cooler, then you might have to lean it a little to get equal power. When cold winter days come around, I quite often have had to richen the engine by nearly a full turn to get "normal" power.

If you're not confident setting the engine though, I'd leave it for a more experienced guy.
Dennis-

I was wondering why my engine was so hot yesterday!

the humidity where i live is insane! it was like spring weather a week ago but now it's crazy hot and humid!


I like spring weather.