I had committed some time ago to document the divergent temperatures reflected from various topcoat paint colors.  Several RVers asked what I was doing and the response was always the same.  Wow...

The Lancairs being composite material do not obtain full cure on their adhesives until they reach Full Set.  With Hysol that comes at around 175 degrees.  Many show planes rush to completion, send it to paint for PPG Concept and clear coat and then Presto - one to two OSH seasons later the exterior paint runs the temperature up to final cure and the filler over the fasteners contracts as the last "Out Gassing is completed".  UV is detrimental to many composites, hence Glasairs and Lancair going with as much white as possible on the upper surfaces. 

Seldom do builders run more than a few months without final topcoat because of the need for UV protection.  RVers on the other hand are Aluminum thinkers.  Enter the RV-10 which has a significant composite canopy (Not aluminum).  My premise is that a lot of RVers with composite canopies and composite engine cowls are going to learn this lesson late.  A have numerous pictures to drive home my hypothesis.  Therefore I promised to document the various temperatures radiated at the next event which turned out to be Today.

All samples were south facing, vertical stabilizers from a distance of 14 inches perpendicular to the reflected surface and the sampled surface facing the sun.  The measuring device was a Blue Point Infra-red thermometer.  The samples were taken from 10:43 PDT to 11:05 PDT to reduce solar load over time.  Due to the variant of composite canopies and Plexiglas, only vertical stabilizers well distanced from the canopies were sampled.  Outside Air Temperature was 71 degrees, sunny skies with less than scattered cumulo-nimbus low on the horizon.  

Here are the acquired samples.

Natural Unpainted, Unpolished Aluminum skin 55
White 71
Lt Lavender 73
Lt Yellow 74
Gold Metallic 74
VANS Yellow 79
Orange/Red 79
Blue Angel Navy Blue 80
Burgundy 80
Dark Red 84
Dark Blue 86
Gray Metallic 87
Dirty Orange 89
Lt Silver Metallic 89
Lt Gray 90
Bright Red 91
Medium Blue 91
Dark Red 92
Turquoise Blue 92
Dark Green 97
Lt Gray 99
Dark Blue 100
Medium Silver Metallic 100
Purple 101
Burnt orange 101
Burgundy Metallic 102
Royal Blue Metallic 104
Hickman Blue 106  (maybe Rob has been there since 7:00 AM)
Jet Black 114

I will do this again at OSH at about 3:00 PM during the middle of the week.  Keep those darker colors lower on the aircraft. Maximize the cooler colors on the top.

John - KUAO