STANDARD MILITARY SIZE’s of FLAGS per original US Government and military regulations.

Garrison flag – 20 feet hoist by 36 feet fly

A Army garrison is a permanent army base.

Post flag – 10 feet hoist by 20 feet fly

A Army post is a military position held away from the permanent base.

Storm flag – 4 feet 2 inches hoist by 8 feet fly(Modern: a small national flag flown (as at a U.S. Army post) only in stormy weather and measuring usu. 9 feet 6 inches by 5 feet)

Infantry, Artillery, and Engineer National Color: 6 feet hoist by 6 feet 6 inches fly(Field flags) REGIMENT FLAG

Camp color:  size18 inches hoist by 27 inches fly

Camp is a temporary army encampment.

The union (canton) in all of these was 7/13 of the hoist by 1/3 of the fly.

There are 15 sizes for Navy ensigns the largest being 19’x36’

Standard size of a military flag is 3′ x 5 ‘

United States flag law does not specify the proportions of the flag. The proportions of 10:19, so often quoted, are the product of an executive order of the president, and are actually binding only in certain military uses. The United States government buys and uses flags in several other proportions (2:3, 3:5, 5:8) for numerous civilian and military applications. Private citizens are free to use their own judgment.
John Ayer, 6 February 1999

The proportions of the U.S. flag are almost the same as those of British naval ensigns in the 1770’s. They attained this rather strange proportion because the table of sizes, issued by Samuel Pepys, Secretary of the Admiralty in 1687, laid down that flags should be made a yard long for every breadth of bewper (bunting) used in their construction. At the time bewper was 22 inches wide, so 22 x 36 gave the excellent proportions of 11:18, which are the whole numbers, near the “Golden Ratio” of 1 : 1.618. Later, bewper was woven in successively smaller widths, but the flags were still made-up in yard lengths. Consequently the proportions changed from 11:18 in 1687 to 1:2 in 1837. In the 1770’s bewper was 19 inches wide, so the flags then had the proportions 19:36 or 9.5:18; very close to 10:19.
Note. The flags were actually made-up in half-breadths and half-yards, but the explanation is simpler if given in whole units and doesn’t affect the proportions.
David Prothero, 30 January 1999

The source for U.S. flag proportions is actually Executive Order 10834
Joe McMillan, 16 July 1999

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