Baffle - 85cc in 100cc Plane

calypso

Well-Known Member
Hey guys, here is an actual RC plane question.

I have mounted my DA85 in an Aeroworks 100cc Edge540. My question is, do you think I should block off the cowl openings that are intended for the 2 cylinder 100cc or leave them open?
 

Attachments

calypso

Well-Known Member
That is what I was hoping to hear. I was originally going to leave them open but then I started worrying that all the air coming in would pressurize the cowl and wouldn't draw air around the cylinder head. There is a large area of exit air opening so it's probably ok.
 

jaguar bone

Member
I've always left the cowl openings as is with zero issues.
The air that enters those openings will simply exit the underside after venting the engine compartment, helping remove any radiant heat in the cowl.

You do have an opening at the bottom of the cowl about twice the size of the top openings, along with the cylinder head opening? If not, I would cut more of the cowl to expose the entire head. Rarely seen anyhow.
 

Attachments

Last edited:

ck1

New Member
Closing the cowl cheek openings will force the airflow thru the engine cooling fins rather than the air coming in the upper openings and bypassing the engine to the exit opening
 

calypso

Well-Known Member
I spoke to Joe Hunt who has put an 85cc into this plane and he recommends exactly that, closing off the cheeks and putting in some baffles to guide the airflow around the cylinder. He also recommended gluing some triangular stock in front of the exit vent holes underneath the cowl to create a low pressure zone there to draw the air out.

It's a bit more work but probably worth it.
 

jaguar bone

Member
I spoke to Joe Hunt who has put an 85cc into this plane and he recommends exactly that, closing off the cheeks and putting in some baffles to guide the airflow around the cylinder. He also recommended gluing some triangular stock in front of the exit vent holes underneath the cowl to create a low pressure zone there to draw the air out.

It's a bit more work but probably worth it.
Never had issues flying a slew of different single cyl.50cc & 85 cc, but I understand too that if you got to fuc with it, have at it. :biggrin:
I did close off this 50cc YAK for that same reason.
 

Attachments

calypso

Well-Known Member
It may not help much but it for sure won't hurt it either. The engine I'm using has been running great in another plane and I don't want to wreck it with a hot run. It's not that much work anyway.

Great job on the Yak btw.
 

jaguar bone

Member
It may not help much but it for sure won't hurt it either. The engine I'm using has been running great in another plane and I don't want to wreck it with a hot run. It's not that much work anyway.

Great job on the Yak btw.
Thanks! Vane painting was inspired from full scale. That Yak had a pretty radical motif. I called it "Tribal". LOL!
 

Attachments

Top