This is the description of the image which is written in HTML and may contain links, images, … .
The Sikorsky H-34 is a piston-engined military helicopter originally designed by American aircraft manufacturer Sikorsky as an anti-submarine warfare aircraft for the United States Navy. Wikipedia
By U.S. Army – U.S. Army photo from the official U.S. Department of the Army publication Vietnam Studies – Airmobility 1961-1971. Washington D.C. 1989  photo , Public Domain, https://commons.wikimedia.org/w/index.php?curid=231332