Engine bogs down on steep climb
 

I have a tower trainer and a OS .46 FX and a 11-6 prop. When doing a steep climb I can hear the engine slowing down. Is this normal? Should I be running the engine leaner or go to a smaller prop? If I load it too hard will the engine stall?

Thanks,

schu

RE: Engine bogs down on steep climb
 

akschu,
it sounds like you motor is leaning out as you fly/climb. This is normal when you are flying. You should adjust your motor on the ground knowing this is going to happen. When you are adjusting your motor on the ground get it to where you want it running and then open it up another 2 or 3 clicks. This will richen it up a bit so that when it leans out in the air it will be running where it should be.

Hope this helps.

RE: Engine bogs down on steep climb
 

The .46 FX with an 11-6 will be a little overpowered on a .40 size trainer. I would not expect it to ever die in the air, in a steep climb. A minor change in the tone is to be expected.

Are you flying it wide open? If so.... why? I could understand if you were flying at about 30% throttle, and the engine tone changed in a steep climb, but there should be no fear of engine stopping.

In my opinion, your trainer time is best spent flying around at about 30% throttle, except after you have progressed to the aerobatics practice stage. At that point, I see no need to fly at more than 30 % throttle except when preparing for a loop, or climbing into a stall turn, or other aerobatics.

At no time would I anticipate that a properly adjusted .46FX would slow down anywhere near quitting - especially not when throttling up and entering a loop or climbing into a stall turn.

If that's what you're doing, and the engine is slowing excessively, I suggest your high speed mixture needle is not adjusted properly - or there is a fuel feed problem.

Good luck,
Dave Olson

RE: Engine bogs down on steep climb
 

I agree that the .46 is a bit of power for the plane, I don't use full throttle except for climbs, but when I do I can hear the engine rpm getting pulled down. I just wanted to know if that's normal. I'll try setting it a few clicks richer next time.

Also, any tricks for getting it to slow down for landing? So far I have had to get it 200 yards out and cut the throttle to just over idle and give it some space to slow down otherwise the the plane is moving to fast and I have to make another pass.

Perhaps another prop would slow it down?

RE: Engine bogs down on steep climb
 

What prop are you using now (size and brand)? A different prop will probably make a huge difference.

RE: Engine bogs down on steep climb
 

I'd recommend going to an 11 X 5 prop, and check your CG. If the plane is a little nose heavy it'll have a tendency to land fast. A more rearward CG will allow it to slow down more for the landings.

RE: Engine bogs down on steep climb
 

An 11-5 will help, but if you have sufficient ground clearance, a 12-4 will be great for slowing the plane down for landing.

RE: Engine bogs down on steep climb
 

Just use a longer final, cut to idle, and hold the elevator back to slow it down. When you get to the speed you want, hold it with elevator and the plane will descend to the runway. It may take a few passes to get the speed you want, but you should be able to land that plane at a crawl.

RE: Engine bogs down on steep climb
 

I have plenty of room for a 12-4 so I will try it. As far as the CG goes, it's setup perfectly on my cg machine so i don't really want to mess with that until I get more experience.

Thanks,

schu