Nurse Baker tells Radar she loves an underdog, claiming she used to root for the St. Louis Browns. The major league baseball team (now known as the Baltimore Orioles) only had two winning records from 1927 to 1943, including a 43-111 mark in 1939 that is still the worst in franchise history.
Major Burns (Larry Linville) calls newly promoted Second Lieutenant O'Reilly (Gary Burghoff) a "shave tail". This is a derogatory slang term for a newly commissioned officer (usually a second lieutenant). The origin of the term comes from the 19th century Army practice of shaving the tail of newly broken pack mules to distinguish them from the seasoned ones.
Army ranks during Korean War: Private, Private First Class, Corporal, Sergeant, Sergeant First Class, Master Sergeant, First Sergeant, Sergeant Major; Second Lieutenant, First Lieutenant, Captain, Major, Lieutenant Colonel, Colonel, Brigadier General, Major General, Lieutenant General, General, General of the Army. Radar's promotion was an increase of six ranks. An experience difference of 701,367.
Hawkeye and BJ, while trying to discourage Col. Potter from calling "I" Corps, claim only two people know how to work the phone: "Radar, and Sgt. Marconi." This is as reference to Guglielmo Marconi, 1st Marquis of Marconi, who was an Italian inventor and electrical engineer known for his pioneering work on long-distance radio transmission and for his development of Marconi's law and a radio telegraph system.
Interestingly, the movie Klinger announces, "One Ticket to Broadway," is completely fictitious. (There was a movie, "Two Tickets to Broadway," released in 1951 by RKO Radio Pictures.) Twentieth Century Fox passed on the opportunity to advertise one of their own movies.