That is correct.  I was in error earlier when I said humid air was more dense.  However, I
stand by my statement that it won't matter as regards oil cooling.  The difference is very
small.

For example, At 90 degrees F, BP of 30, at sea level, and with 20% humidity, the air density is
89.5234986.  If you leave the other factors alone and raide relative humidity to 80%, the
density falls to 89.0660145.  This is a drop of about 1/2 percent, and would not have a
significant effect on cooling.  Maybe on airplane flight characteristics, but not cooling.

Now, I never said that humidity never matters.  I just said it doesn't matter when you are
talking about air flowing over an oil cooler.

Bill

----- Original Message -----
From: "Ed McLean" <email99@BELLSOUTH.NET>
> I agree with Arlen completely.
>
> Humid air is less dense than dry air and will consequently be less
> effective at cooling.