COZY MARK IV S/N 0018
N91KS
Link to Interesting Photos
Link to FLIGHT LOG
LAST UPDATED 2/10/2006
COZY Mark IV N91KS

I started my project in Jan 1991 and just completed the DAR inspection May 28, 2004. Why did it take me 13 years and 4 months? Well I figure I lost about 5 years between moving 4 times, changing jobs 3 times, divorce, remarriage and the usual obstacles live puts in your way. That's still a long ways from the 3.5 years it took my Dad and I to do the first Cozy (3 place). I didn't keep a log of my time until past the half way point so the chapter log for the early part is based on the nice log that Marc Zeitlin kept, which I think is representative of my time as well. The total time comes out to 2915.5 hours.Link to Breakdown That's about 400 hours over the plans estimate, which is due at least in part to the mods that I have done.
MODIFICATIONS

Here's a list of areas which differ from the standard plans Cozy:

Engine: Subaru EG33/Ross PSRU:
     I pretty much blutantly copied Phil Johnsons installation but he was able to save more weight than me in several areas. I choose this engine primarily for reliablility, secondly for cost and third for power and efficiency. Having flown airplanes powered by Lycomings for 40 years, I am not impressed with their reliability compared to cars. I can't see spending over $18K for a IO-360 and ending up with less power and less efficiency. I have total of about $10K in my Subaru including everything firewall aft. It will put out 230 hp stock. I don't plan on using that much HP but I can go to WOT at 8000 feet (either for T/O or cruise) and get 172 HP where the O-360 would only put out 135 HP. This will give me better takeoff performance and cruise speed. The specific fuel consumption is expected to be about .45 lb/hp/hr compared to about .55 for a O-360. That's about 18% better fuel economy. Of course this is all pie in the sky at this point since I've barely strated flying. Here are some photos

Remote Fuel Valve:
  I didn't care for the idea of running fuel lines all thru the cockpit and I don't like the fuel valve on the front seat bottom. This is hard to see and hard to reach. I ran a torque tube thru the heat duct from the MLG bulkhead to thru the Instrument panel. I then ran a cable drive up to a fuel selector mounted in front of the throttle quadrant. The valve is mounted on the MLG bulkhead and is a Left/Off/Right type valve. The fuel lines run directly from the tanks to the valve aft of the rear seat.

Canopy Roll Over Structure:
Many times in the Cozy 3 I found that I wanted to put something long in the back seat, like skis or fishing poles but couldn't because of the canopy bulkhead. The head rests and the bulkhead also block the rear seat view. Instead I beefed up the upper perimeter of the bulkhead and cut out all but the perimeter. This creats a roll over bar similar to those seen on cars. I pinned the roll over bar to the longerons on both the left and right to support it if the plane were upside down.

Matco Brakes
After loosing my Cozy 3 at least partially due to woefully inadequate brakes, I decided that this airplane would have adequte brakes. I chose the Matco 3 puck system. There is a full disussion of this subject on Phil Johnson's web page. Now that I've gone with the electric retract, this makes even more sense since the emergency use of the retract to skid to a stop will take about 20 seconds making that unuseful.

Removeable Instrument Panel
I have a pretty full panel. By the time I got to cutting holes for all the avionics the panel structure was escentially gone. I decided to cut most of the panel a way and use a 0.125 sheet of aluminum. Photos

Full Length Canard

I've seen a large variation in minimum flight speed and rotation speed from one Carard type aircraft to another. My Cozy 3 did not rotate as slow as many. Since I had already built my canard before the plans change cut it down 6". I decided that I would fly the full length canard first and compare the neutral point to the prototype model. I will then cut off some if it is so indicated.
Continue to additional Modifications