Message-ID: <004101c3bda7$0b210f90$6601a8c0@richard>
From: "Eric Ruttan" <ericruttan@chartermi.net>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
References: <list-2881730@logan.com>
Subject: Re: [FlyRotary] Air Density at altitude
Date: Mon, 8 Dec 2003 11:19:21 -0500
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> Found a table of air density vs Altitude
>
> Sea level Density = .00237 Slug/Ft^3
> Density at 20,000 = 0.001267 Slug/Ft^3 or a 47% decrease
>
> So taking formula for air mass  W = p*V*A with p 47% less than at sea
level
> means you would get 47% less air mass flow (with the same cubic
feet/minute
> of air volume flow) at 20,000 ft compared to what you would get at sea
level
> for the same volume flow.
>
> While cooler temps would help, it would not compensate for a 45% less air
> mass flow.
>
> Ed

But Jim does have a point.
Indicated Air Speed should be an indication of mass air right?
So if it cools enough at X mph IAS, it will work at any altitude at X mph
IAS?
And this should mean that the cooler air would give an advantage as the mass
air is cooler.

P.S.
I, as many I am sure, deeply appreciate your work in our behalf.  If we may
ever assist you please let us know.