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Just discussing the need to use the minimum amount of cooling air and get it into the engine compartment, through the fins, and out in the most efficient way.

FYI here are pics of a Lancair cooling system by the late Paul Lipps (pics 1-4).  A number of folks have used on-top plenums on their canards similar to pics 3 & 4.  I used a similar plenum on my EZ project (pic 5) but notice that Lipps also wrapped the cylinders to get (I suppose) even airflow around the fins.  That seems a more complicated than necessary; the top of my cylinders were left open, inside the plenum but if Lipps' idea works . . ..

He has small intakes and a nice transition to the plenum.  I am not sure they could be that small if they weren't on the front of the airplane and getting a prop blast.  The most interesting thing to me are Lipps' cooling exit ducts coming off the bottom of cylinders.   (pic 1)

Couple of pics of my EZ intakes here for comparison.

 

My EZ cooled well in cruise but got a little hotter on climbout.  If I kept the speed around 120 KIAS, it was satisfactory.

Here are some other plenum and intakes courtesy of Phil Camarda

http://longezpilot.com/PG10 DD Inlet Scoops.htm

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Seen on a FB page:  This ain't going to work, I'm afraid.  A nice NACA duct that abruptly ends in two holes for "oil and ram air".   It totally defeats the reason for the NACA duct and square-edge holes are aerodynamically smaller than they appear.  Imagine all the turbulence in front of those holes, too.  At least the Cozygirrls were pointing that out to him.  Well, that's Facebook.  

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While I have not yet built a cooling system on my project, it is a subject I have studied a fair amount, as it is one in which you can make good gains, or mess up entirely. Creating a restriction like that is a sure way to the latter end!

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I reprint this from a post on the Cozybuilders list. Take it for what it's worth. This fellow finished his Cozy with a Subaru about the same time as I finished mine.  He made a valiant effort to make the Suby engine work but personally, 8 dead-stick landings are about 7 more than I could stomach before rethinking the idea. He is looking for a Lycoming.  I have put two Subaru engines in Vanagons.  Great engines but I don't trust them in canard airplanes.   He did a great job landing the airplane.  I have landed at Fullerton and it made me pucker even with a good engine (pic).  3100' R/W!  Yikes!  At least the landing roll is shorter with a dead engine.   Landing in a warehouse will also shorten it up a bit, too.  🙂

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Yeah made my 8th dead stick landing Sat. at Fullerton airport. I climbed out of KCPM and joined formation with a Velocity and a LE headed for Bermuda Dunes for a flyout.. We (wisely) climbed to 3500 over KCPM in order to clear the class D at KFUL. As I mentioned before, my oil pressure has been on the low side but within limits and filled with oil on preflight. There may have been a little unusual noise but nothing alarming. KFUL is only about 10 miles from KCPM so I as up only about 10 min. First I noticed a small RPM loss. I declared and emergency to the formation and did a 180 for KCPM. By the time the 180 was complete the oil pressure was zero  and I knew KCPM was out. Seconds later the engine froze. I called KFUL and declared an emergency. They cleared me right in on a downwind entry. A CFI taught me to fly thru the "magic box". This is a point in your standard pattern where you always cut the power full off and then you fly from there to base and touch down on the numbers. I've been doing this for at least 5 years. It worked perfectly. I touched down on the numbers coasted down the runway and off to a parking spot...just like Bob Hoover :)
 

 

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Here's something new to me:  A way to stiffen air-cooled cylinders.  http://www.skydynamics.com/products/engine/top-cylinder-girdle    I wouldn't doubt that those cylinders vibrate, ring, or flex quite a lot.  It seems like a good idea but is rather pricey.  Besides, most engines just rust out before they wear out.

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Sealing up the airplane:  If you can keep drafts out of the airplane, sunlight will almost keep you warm enough.  We use sweaters, a heat muff and sunlight.  It is pretty comfy down to 0F.  I am not in favor of oil heat simply because it adds weight, complexity, adds to the build time and is probably not necessary in a lil' 'ol homebuilt.  Electric heaters use a lot of amps.  Better to just seal up the airplane and wear a sweater.  If I flew more in cold weather, I would add an inline fan with the heat muff.

I am sorry I used a fuselage door with a Hartwell latch.  It leaks so much air I wear a glove on my stick-hand in the winter.  Below is door idea that can be sealed up rather well.  Some folks have hidden latches that don't need a door.  Pic 3 is a pic of my canard off the airplane, bottom side.  The air-dam between the elevator and canard matches a similar air-dam on the fuselage so it's pretty tight.  My airplane was pretty airtight until I added an electric nose gear mechanism.  I will probably make a cover for the motor-head and NG30s one of these days.

To make a canopy seal, I used balls of modeling clay, shut the canopy against them and measured how much they got squished to make a canopy seal with hardware-store seal built up as necessary with 3M double-stick mounting tape.  That works pretty well.

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It’s good to query “cozy” or “longez” or “long-ez” at the NTSB site and read accident reports

https://www.ntsb.gov/_layouts/ntsb.aviation/Index.aspx

Many of these I’d forgotten but there are things I pay special attention to today because I read something in an accident report: things like inspecting the gascolator regularly for debris, leaning for takeoff at  high density altitude takeoffs, being very careful when exploring the stall in a new airplane.  Those things have trashed new airplanes and killed or nearly killed pilots.  

These days, lots of people are buying flying canard airplanes. Idealy there would be a course on lessons learned with them. There isn’t, so you have to teach yourself by reading the reports.  Those are just the documented accidents, though.  You will find a lot of less serious incidents in newsletters and mail lists.  These are safe airplanes but they can still bite if you don’t know their history. 

Edited by Kent Ashton

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Another good site to read every day is Kathryns Report.  Saw this one this morning where a couple of very experienced flyers in a T-6 make a very tight turn at 200-300' AGL after takeoff, get the nose buried and died.  That happens.  Turning hard, looking out to the inside of the turn, fail to notice the fuselage angle is beginning to point down.  http://www.kathrynsreport.com/2019/02/north-american-snj-5-at-6d-texan-n12377.html

The most prominent example I can think of is the Fairchild AFB B-52 crew that got the nose buried in a sharp turn down low.  You can see the spoilers come up as they try to roll out but it's too late.     https://www.youtube.com/watch?v=0HJ4z1jGEcA

That accident is memorable for a lot of things.   http://www.check-six.com/Crash_Sites/Czar52Crash.htm

 

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