"Orval Fairbairn" wrote in message
news
Remember, too, that air can travel forward on the fuselage, from rear
stagnation points. If the canopy is well-streamlined, a port on the aft
end of the canopy will provide ventilation to the back of your head,
because pressure there is higher than on other parts of the plane.

This is very true on my Emeraude. Air - and sometimes rain - will enter at
the rear of the canopy where it meets the fuselage. I had to carefully
weather-strip that area. Air also blasts in through any holes between the
cockpit and the interior of the rear fuselage, i.e. the flap actuator rod. I
think that air is entering near the tail and coming forward toward the
low-pressure cockpit. I tried to establish a good seal with the carpeting
using Velcro at the edges to keep that air out - especially in wintertime.

I have two NACA style vents on the sides of the fuselage located below the
windshield supports. They pressurize a "bay" of the fuselage sidewall and
the air then enters the cockpit through an eyeball fitting elsewhere in the
bay. The air has to turn a couple of corners, filtering out water and/bugs.
The vents are about 4" top to bottom. They really give a nice blast of air -
enough to stay cool. Air leakage at the rear corners of the canopy help with
the back of the neck, but I lay a couple of rags on them in the cool wx.

The *best thing* I did was to install the interior canopy shade sold for
RV-6's by Cleaveland Aircraft Tools. It is absolutely invaluable in any sort
of sun.

Rich S.