Posted for Perry Mick <pjmick@viclink.com>:


Ed, I think I have the record for minimal number of cubic inches of rad cooling a rotary.

The finned volume of my rad is only 12" x 14" x 1.5" (not including the end tanks). This is only 252 cubic inches. I also have a 1 x 3 x 9 cooler plumbed to the heater port for cabin heat, that is always on, only the heated exit air is controlled into the cabin. So that is another 27 cubic inches. Total is less than 300 cubic inches.

It only works for me because I am producing relatively low power, 120 HP @ 5200 RPM in climb. And I have ducted-fan assisted airflow through the main rad. Should I produce more power in the future this will probably not be sufficient radiator.

Trying to get more rad into a plane like the Long-EZ, just not sure how you would do it. I think Joe Berki has removed some of the fuselage below and behind the main landing gear, that should help.

I use the NACA inlet to my rad also, but I expect it would not work so well without the ducted fan or if your rads get thicker.

I know Al Wick and have flown in his plane. With just Al, me and my 10 year old son on board, I think it took more runway for him to takeoff than I normally do, and his climb-rate was less. So I believe he is not making that much power, and his plane is not really a four-place airplane. Also, I think the cooling requirements for a Subarooo just cannot be directly compared to the rotary.

I'm trying to think of a canard pusher flying at the moment under rotary power, using a conventional prop, that Paul Conner could use as a guide. I can only think of Ron Gowan's EZ that flew several years ago. Of course there are several Cozys etc. under construction, so there is still some trailblazing to do in this area. Fortunately for Paul, he can get a larger rad in his plane than I can get in mine.

--
Perry Mick
Custom Composite Props
mick@bridgingworlds.com
http://www.ductedfan.com