Throughout the series, whenever something was amiss or trouble was brewing, Fuji would exclaim, "Oy vay!" This is not a Japanese expression; it is a Yiddish one meaning, "Oh woe!" He said it so regularly that in one episode McHale said, "It's just like Fuji would say if he was here.." and the crew said in unison, "OY VAY!!"
The vessel used for shots of the PT-73 underway was a 72-foot type II Vosper MTB (Motor Torpedo Boat), a British design built under license in the U.S. for export to Russia. The war ended in August 1945 before the boat--the real number of which was PT-694--could be sent to the Soviet Union. The boat was then purchased by billionaire businessman Howard Hughes and used as a chase boat for the one and only flight of his Spruce Goose aircraft. The boat was then sold to Universal Pictures--as there were few other real PT boats left in existence at the time--and some liberties were taken in reconfiguring it to look like a PT Boat. Vosper PTs did not have machine gun turrets on either side of the pilot house (though ironically, the real PT-73--a Higgins design--did) as the PT-73 in the show did. Other irregularities are the main mast aft and a small mast right in front of the cockpit. Shots of the crew aboard the PT-73 were filmed on a full-scale mock-up in a soundstage. "PT-73" was later sold to the mayor of Hawthorne, California, and was converted to a sport fishing boat. It was destroyed when it broke loose of its mooring near Santa Barbara and washed up on the beach during a storm. The real PT-73 was a 78-foot Higgins boat assigned to Motor Torpedo Boat Squadron 13, which saw service in the Aleutians and in the Southwest Pacific theater. On 15 January 1945 it ran aground and was destroyed to prevent it falling into enemy hands.
The hull section prop of the PT-73 can be seen on an episode of the TV show Emergency! titled "Ouicker Than The Eye" (1974). In the segment, an employee of a movie studio becomes trapped under the hull of PT-73 when it is being moved on the studio back lot and the crew from Station 51 came to rescue him.
During the final season, McHale and his crew, along with Capt. Binghamton and Lt. Carpenter, were shipped from the Pacific theater of operations to the European theater. In reality, transfers of this nature rarely, if ever, occurred.
Whenever one of the crew's elaborate schemes calls for President Franklin D. Roosevelt's dog, Fala to bark, they sometimes bark like a big dog and then bark like a smaller dog. FDR had six other dogs besides Fala - Meggie, another Scottish Terrier and five others that were large breed dogs - Tiny, an Old English Sheepdog, Winks, a Llewellyn Setter, Blaze - a Bullmastiff, President, a Great Dane, and Major - a German Shepherd.
The hull of the PT-73 prop boat can be briefly seen on an episode of Columbo titled "Fade To Murder" (1976). The hull is visible in the background during a scene when guest star William Shatner is walking across the back lot of a fictional TV studio.
Captain Binghampton's job before the war was running a yacht club on Long Island Sound. In other episodes, his job was editor of a yachting magazine. In one episode, the Captain is seen wearing a sweatshirt that says "San Diego yacht club."
The only extra included with any of the DVD sets that were issued beginning in 2007 was a reunion video featuring five of the surviving cast members as of that year: Ernest Borgnine, Tim Conway, Carl Ballantine, Edson Stroll, and Bob Hastings. (Joe Flynn died in 1974, Gary Vinson committed suicide in 1984, and Billy Sands also died in 1984) the other cast members who did not appear in the video are apparently alive as of 2016.) As of 2016, the only surviving member of the group featured in the 2007 reunion is Tim Conway.
In some early episodes, McHale referred to Ensign Parker as "Charlie", although in later episodes he called Ensign Parker "Chuck". McHale was the only one of the crew to refer to him in that way. The rest of the crew called him "Mr. Parker".