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# Re: Flag Drag

• To: rkazanjy(--nospam--at)gmail.com, seaint(--nospam--at)seaint.org
• Subject: Re: Flag Drag
• From: Rhkratzse(--nospam--at)aol.com
• Date: Tue, 12 Sep 2006 00:10:20 EDT

That's very interesting.  Thanks.

So supposedly the type of flag will never be changed.  I don't do flags, so this is out of my field, but I just think about the situation if the wind forces were 40% different on a stucco (say) building than on a wood siding building, and what would happen if one were remodeled into the other sometime.

Ralph

In a message dated 9/11/06 8:50:55 PM, rkazanjy(--nospam--at)gmail.com writes:
On 9/11/06, Rhkratzse(--nospam--at)aol.com <Rhkratzse(--nospam--at)aol.com> wrote:

In a message dated 9/11/06 11:57:45 AM, nma(--nospam--at)omsoft.com writes:

Use ANSI/NAAMM FP 1001-97.
Equation 4 will give you the wind load for nylon or cotton flags.
Equation 5 will give you the wind load for polyester flags.

Just out of curiosity, how much variation is there?  I wouldn't have thought the flag material would make much difference, but apparently it does.

Ralph

Ralph-

looks like polyester gives a 40& increase over cotton/nylon

Nylon: Drag(pounds) = 0.001 x (V,mph)^2 x Sqrt(Area, sq. ft)

Polyester: Drag(pounds) = 0.0014 x (V,mph)^2 x Sqrt(Area, sq. ft)

cheers
Bob