U.S. 50 Stars Union Jack - Vietnam Era.
This is a lightweight, nylon Size 5, United States Jack, rigged finished with a snap and ring and marked 1967. It shows wear consistent with use, but the name of the ship which wore this jack had been lost to history. It was acquired from a Monterey Bay Area surplus store in the 1970s and the fabric (a lightweight oxford weave nylon) is consistent with the type of nylon prescribed by the US Navy during the eras of the Vietnam War and the American Revolution Bicentennial, when the US Navy used smaller denier nylon.

A jack is a maritime flag of national character. The U.S. union jack consists of the blue canton of the US ensign. The U.S. Navy uses most US jacks, but ships of the US Coast Guard, US Military Sealift Command, US National Oceanic and Atmospheric Administration, and other US governmental entities also wear them. Merchant and civilian pleasure vessels occasionally wear them.

Jacks like this 50 star example have been the standard jack of the United States since 1960. Jacks are flown on the jacktaff at the bow of all U.S. naval vessels while at anchor or while dressing ship. It is also flown from the yardarm during a general court-martial or court of inquiry. During times when the ensign is at half-mast, the jack is also at half-mast. The jack is hoisted smartly and lowered ceremoniously in the same manner as the ensign; however the jack is not dipped when the ensign is dipped.

According to US Navy Regulations, jacks are intended for use at sea, they are never flown ashore. The size of the jack is always the same as the size of the canton of the ensign at the flagstaff. The jack is displayed only during the hours between 8:00 a.m. and sunset, when the ship is not underway and the ensign is flying on the flagstaff. If the ensign is half-masted, so is the jack.
Finally, the union jack is displayed at the bow of a boat whenever a U.S. chief of diplomatic mission is officially embarked in the waters of the country to which he or she is accredited, or when a governor general or governor commissioned by the President is embarked within the waters of the territory of which he or she is in charge.

Provenance: Acquired by purchase at a Monterey Bay Area surplus store, J&S Surplus, Moss Landing, CA.

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