Unusable Fuel. I've done unusable fuel tests in a high wing tailwheel aircraft, but never in the midwing Cozy, with fuel sumps at the wing root. The Andair fuel valve does not have a setting that feeds from both tanks. The reg reads: "�59 Unusable fuel supply. (a) The unusable fuel supply for each tank must be established as not less than that quantity at which the first evidence of malfunctioning occurs under the most adverse fuel feed condition occurring under each intended operation and flight maneuver involving that tank. Fuel system component failures need not be considered." There was a recent discussion of this on the Cozy builders group, concluding 1) land on the fuller tank; and 2) landing slips should either keep high the full tank wing or limited to 10 seconds.

Fuel Capacity. A fuel specification and tank capacity is to be marked on the aircraft, a guard against the inexperience of the person on the fuel truck. This is normally done with either decals / stickers on the aircraft or engraved fuel caps [see note below]. The process is
a) verify all fuel lines are secure, valves closed and fittings are snug
b) set longerons at level to 2 degrees nose down (inflight is 2-4 degrees up, level is the landing attitude)
c) put masking tape on the sight guages, an ohm meter on any resistive fuel capacitor or capacitor series
d) prepare a tank stick - a paint stirring stick painted flat black or white will work. Mark one side right, one left. Best to call it a refueling aid: if you treat the stick as a fuel guage, it falls under 14 CFR 23.959(a) - see above.
e) support the wing on the side being filled - one side empty and one full could lead to embarassment.
f) fill and mark (in pencil!) in the increments you think will work for you - I like 5 gallon increments, perhaps because that's the size of my fuel containers!

I found that my Atkinson sight gauges are stuck - fuel is barely creeping in and the red ball is not floating free. The Cozy mailing list has the solution...

Notes on resistance (in k ohm) of the fuel level senders:
fill Left
5 g
10 g
15 g 95.0
20 g
25 g 115.0
28 g 115.6


Out in Utah there is a print & layout shop happy to laser engrave fuel caps for all of $8 each. Contact
Aeryk
Jet Blast Designs
2474 South 1500 East
Vernal, UT 84078
435-823-1890