I recently finished watching the entire 11 season run of M*A*S*H, the hit television show that ran from 1972 to 1983. Although the story about a mobile army hospital was based during the Korean War, it became an allegory for the Vietnam War, which was raging when M*A*S*H the feature film was made (1970) and the series began. Ironically, the series ran three times longer than the actual war. The production got better as time went on, but the producers stayed with the same script throughout: a little comedy sprinkled throughout a sad commentary on war. There were many constants throughout the long run, especially in sound design, which is pretty impressive. See if any of these sound cues bring back memories:

•The title song. The song, "Suicide Is Painless", was written for the original film and adapted into a quasi-1950's style instrumental for television, keeping the acoustic guitar opening. There were two versions and the length changed several times, from 90 seconds in the pilot, to 45 seconds in most of the following episodes.

•The PA announcer. Although company clerks Radar O'Reilly and Max Klinger were sometimes on the mic, it was usually some unseen person with a high-pitched voice alerting the camp to incoming casualties. Two actors played the announcer, Todd Susman and Sal Viscuso. Susman did the bulk of the roles, and both actors appeared in a few episodes as wounded soldiers.

•The helicopter. One of the classic plot points in M*A*S*H was Radar "hearing" an incoming helicopter before anyone else. He would announce that a "chopper's coming," making everybody – the characters and millions of viewers – to stop and listen. This was a fantastic use of silence. I always wondered why he never heard the trucks with wounded before anyone else. The style of helicopter used during filming was the Bell 47 (technically a Bell H-13 Sioux, the civilian version), manufactured from 1946 to 1974. It was also the helicopter used for evacuations on the battle front during the war. One of the helicopters used in the show (the one in the picture above) recently underwent a complete restoration.

•Sounds of war. Typical MASH units were only 20 miles behind the front, some as close as 5 miles. With the early back-and-forth of surging and retreating, some MASH units found themselves behind enemy lines. There were stray bombs, bullets, planes, and enemy soldiers in the series. First hand accounts of actual MASH units imply that the television show got it mostly right, and probably on the conservative side.

•The cold arctic wind. In more than a few episodes the 4077th would find itself fighting to stay warm in the deeps of winter, the wind howling through the thin tents. The Siberian winds from the west would plunge Korea into sub-zero temperatures with regularity. From November 27 to December 13, 1950, the Battle of Chosin Reservoir was fought while temperatures dropped to -54° F.

Because this was television, we aren't supposed to hear the usual mundane sounds someone in an actual MASH unit might have heard:

•More people. The show M*A*S*H had a small facility compared to actual MASH units. Early in the war, the seven MASH units had 60 beds, was increased to 150 beds pretty quickly, and eventually to 200. Instead of a 80 to 100 people, real MASH units had at least twice as many personnel, some even had several hundred.

•The generators. Although the 4077th would occasionally have a blackout or two, actual MASH units relied heavily on generators. These would have been massive freight-sized units on large trucks. If a MASH unit was in one place for an extended time, as was the case when fighting became stagnant by 1952, power lines may have been run from larger nearby bases, albeit at the risk of being cut.

•The communications. In the series, the company clerk had a telephone switchboard, which probably wasn't the case in real life. I don't recall ever seeing a radio in the show, but actual MASH units relied on them. The Korean terrain was mountainous and very rugged, making communications difficult. To run communication and power lines, cable could be dropped by helicopter or light aircraft. Telephone lines were always at risk of being sabatoged, and radio transmissions were subject to enemy interception and jamming. But most MASH units communicated with incoming medivac helicopters via radio, which meant that the company clerk really did know that choppers were coming before anyone else.

•Deliveries. Because the terrain was rough and largely undeveloped, the Army relied on jeeps, trucks, airplanes, helicopters, and even carrier pigeons to deliver messages. Because delivery by jeep could takes days, planes carried communications – as much as 34,000 pounds of messages a month – between the 8th Army HQ and field commands.

•Bug Outs. The whole idea of a MASH unit was to be mobile (Mobile Army Surgical Hospital). In the early years of the war (1950-1951), MASH units would move, or "bug out" at least once a month. The front lines were very fluid, and with MASH units serving 15-20 miles behind the fighting, frequent moving was necesary. As the fighting stabilized in 1952 along the 38th parallel, some MASH units remained stationary for long periods of time. Moving a MASH unit could be accomplished in 24 hours, no small feat.

•Chinese bugles. The Chinese military used radios, just like the American and UN forces in Korea. But they often used bugles, whistles, flares and lights to signal orders and information. UN soldiers reported that they dreaded hearing Chinese bugle calls on the front because it meant soldiers were on the move. The Chinese Army developed a complex system of bugel calls over the last century that has become a spiritual treasure of the People's Liberation Army (PLA). A typical Chinese company would have a bugler, a battalion a bugler squad, and even a whole bugler platoon for a regiment. Any one of these buglers would have surely played it better than Radar did.

•No laugh track. The producers originally wanted M*A*S*H to have no laugh track, but CBS brass wasn't having that. So a compromise was struck: no laugh track during any surgery scenes. Several episodes omitted a laugh track altogether. Some international versions had no laugh track, and the DVD sets have the option to turn it off. The track was more intense during the first five seasons, but season 6 until the last show was more subdued. Early test audiences found no difference in humor between versions with or without a laugh track, but the network wouldn't relent.

MASH units were eventually phased out by 2006. The modern equivalent is the Combat Support Hospital, which relies on transportable modular containers. Interestingly, tents are still deployed as in MASH units, but the container units are expandable and create sterile operating rooms nearly equivalent to standard hospital ORs.