Alan Alda, who played Captain Benjamin Franklin “Hawkeye” Pierce on MASH, started writing episodes for the show early on in season one. The first episode penned by Alda was Season 1, Episode 19, The Longjohn Flap, a title Alda hated. It aired on February 18, 1973.

Season 1, Episode 19: The Longjohn Flap
In The Longjohn Flap, the camp is experiencing a brutal cold snap. Hawkeye, mercifully, receives a pair of long john underwear from home. Hawkeye puts on the long johns and gets into his cot. Trapper plays on his sympathy, feigning a cough, until Hawkeye grudgingly gives him the long johns to wear. Trapper then loses the underwear to Radar in a poker game, and from there they are passed hand to hand to every principal character in the camp, including Col. Henry Blake.
Radar first gives the long johns to the mess cook in exchange for a whole lamb roast, with mint jelly and all. The cook then gives them to Frank Burns in exchange for him not demoting the cook for the filthy conditions of the mess. Frank gives them to Margaret to prove his devotion, and then Klinger steals them from Margaret’s tent.
Klinger, in a fit of guilt, confides in Father Mulcahy and, while they are talking, runs off and leaves the long johns behind for the Father to deal with. Mulcahy turns them into Col. Blake, but not before wearing them himself in order to have a nights sleep. Henry claims that he will see to it that the underwear is returned to its rightful owner. But, of course, he puts them on, instead.

Hawkeye and Trapper catch Henry putting on the long johns and Henry refuses to give them back to Hawkeye. Then, Henry’s appendix goes acute and he needs an emergency appendectomy. Hawkeye must therefore operate to save his life. Henry pleads for him to “save the long johns” before they put him under. Afterward, Henry gives the underwear back to Hawkeye out of gratitude.
Theme of Episode
Like many early episodes, this episode centers on the inefficiency and comically absurd ineptitude of Army bureaucracy. The reason everyone in camp is freezing is because they received a shipment of warm-weather clothing instead of heavy winter gear. Alan Alda, in his autobiography, Never Have Your Dog Stuffed: and Other Things I’ve Learned, said that he borrowed the structure of the plot from La Ronde. Instead of sexual partners being passed around in a circle, a pair of long johns is passed around.
While Alan Alda was the actor who penned the most scripts, he was not the only MASH actor to write episodes for the show.

