WASHINGTON -- Despite acquisition difficulties caused by an inter-service rivalry with the U.S. Air Force and the technological immaturity of the U.S. helicopter industrial sector, Army Aviation's helicopters made significant life-saving contributions during the Korean War.The Army helicopters initially deployed to Korea were the Bell H-13 Sioux and the Hiller H-23 Raven, the first in a long line of Army helicopters named for Native American tribes. The service had acquired the Sioux in 1946, but had just 56 in its inventory when North Korea invaded the south in June 1950.The 2nd Helicopter Detachment arrived in theater in November 1950 with four Sioux aircraft. Among the early missions assigned to the unit were utility, wire laying, liaison, and reconnaissance missions.In January 1951, four helicopter detachments were assigned to the 8th U.S. Army surgeon, and on the third day of that month, 1st Lt. Willis G. Shawn and 1st Lt. Joseph L. Bowler flew the first Army aerial medical evacuation (MEDEVAC) missions.Dubbed the "Angel of Mercy" by Soldiers on the battlefront, the aviators used the H-13 to transport 18,000 of the war's total 23,000 casualties to forward deployed mobile Army surgical hospitals.As the iconic symbol of the MEDEVAC mission during the Korean War, the H-13 Sioux helicopter became familiar to American television audiences years later when it was shown in the background title shot of the "M.A.S.H" series, which aired from 1972 to 1983.Also supporting the MEDEVAC mission were a small number of Hiller H-23 Raven helicopters that arrived in theater in February 1951. In November 1952, the Army organized its first purely medical aviation unit: the 49th Medical Detachment (Air Ambulance).Because of the hazards to which the primitive aircraft were subjected, particularly their vulnerability to enemy fire while on the ground, the 8th U.S. Army surgeon set limits on the use of helicopters, including restricting aerial MEDEVAC to only the most serious cases.But pilots often ignored constraints like pickups only at MASH units or evacuations only during daylight hours in order to reach wounded Soldiers at night in isolated locations.In addition, although the aviators had no formal training in casualty care, they became adept at improvising ways to move the wounded more safely and in greater comfort within the two exterior pods with which the Sioux and Raven helicopters were equipped.The success of the MEDEVAC techniques pioneered by Army helicopter pilots was most dramatically revealed in the reduction in the death rate of evacuated patients before they reached medical facilities from 4.5 percent during World War II to 2.5 percent during the Korean War.In addition to shortening the time it took for seriously wounded troops to reach treatment, the use of aerial MEDEVAC in Korea eased the extra stress placed on the remaining ground troops who had to carry and care for the sick and wounded not airlifted off the battlefield.The accomplishments of the original Army helicopter pilots were first recognized in 1952 by the inception of the Solopilot Society, which honored the aviators who performed all the duties--pilot, medic and crew chief--of their individual aerial ambulances.The second momentous development in the Army's use of helicopters in Korea occurred in July 1952, when the 6th Transportation Company (Helicopter) received the H-19 Chickasaw, the service's first true cargo and troop transport helicopter.Capable of traveling faster and farther than the H-13 Sioux, the aircraft also held more cargo, could MEDEVAC four to six litters with one onboard nurse, or transport eight fully-equipped Soldiers. The unit began training on the aircraft at Fort Bragg, North Carolina.Although the Army deployed its Chickasaws late in the Korean conflict compared to the U.S. Marine Corps' (USMC's) aircraft, the 6th Transportation Company began operations in theater in January 1953 and received its first mission in March of that year.As part of Operation Terry Blue, the unit resupplied elements of the 3rd Infantry Division, which had been cut off from their supply chain by flood waters, airlifting almost 34,000 pounds of critically needed fuel, ammunition and food.During Operation Sky Hook in May 1953, the 6th Transportation Company (Helicopter) joined the 13th Transportation Company to form the 1st Transportation Army Aviation Battalion (Provisional) to support the 25th Infantry Division by delivering essential food, water and other needed supplies.Army rotary-wing cargo units teamed with USMC H-19 Chickasaws in June 1953 as part of the largest helicopter operation of the war with 45 aircraft transporting 800 Republic of Korea troops. Previously, in April 1953, the two services teamed up for Operation Little Switch, evacuating nearly 700 sick and wounded Allied prisoners of war.In August 1953, the 6th Transportation Company (Helicopter) partnered again with the 13th Transportation detachment for Operation Big Switch, making more than 1,100 flights in a 33-day period to transfer 5,600 released American and Allied POWs from the exchange point at Panmunjom to freedom and safety in the south.Not long after the ceasefire on July 27, 1953, Army helicopter pilots participated in Operation Broadway, helping to carry more than 5,000 Indian troops from aircraft carriers at Inchon to their new post in the re-established demilitarized zone, where they would monitor the ceasefire agreement.Despite the aircraft's late arrival in theater, the Army's H-19 helicopters and pilots accomplished much by performing the service's first air assault missions in combat as well as assisting with MEDEVAC and critical resupply efforts.Army aviation rotary-wing units overcame the serious obstacles caused by Korea's harsh terrain and weather, as well as enemy firepower, inadequate spare parts and lack of trained personnel.Between January and July 1953, the 6th Transportation Company (Helicopter) flew over 4,000 hours, lifted 5 million pounds of supplies, transported 500 troops, and evacuated 1,400 sick and wounded Soldiers, with only one aircraft lost due to engine failure.By bypassing the often severe limitations of land transportation, Army helicopter pilots demonstrated the enormous benefits of cargo lift and troop-carrying aviation, thereby influencing the formulation of the Army's emerging air mobility doctrine.By 1955, according to an article published in the Redstone Rocket, organic aviation had become the fourth element of the Army's then-modern combat arms:"Just as fixed-winged aircraft earned its place in the Army unit during World War II, helicopters earned their "wings" in Korea ..."Why the emphasis on aircraft? On the battlefield of the future, operations will be dispersed, the combat zone will be deeper and operations will be much more fluid than past commanders could have visualized. In the battle zone, air transportation -- in quick response to the will of the commander -- will have the capacity to transport reserves and supplies to critical points ..."However the aircraft are deployed -- wire-laying, bridge emplacement, supply or resupply, medical evacuation, smoke laying, reconnaissance, troop movement, courier, armor column control -- they take with them two American military traditions: To get there 'fustest with the mostest' and to 'hit 'em where they ain't.'"They are the essence of the mobility upon which the Army of the future must rely for victory."