“11th Airborne Division (United States)”的意思、由来-开放百科全书

472nd Glider Field Artillery Battalion (75mm)
674th Glider Field Artillery Battalion (75mm) (converted to a Parachute Field Artillery Battalion July 1945)
675th Glider Field Artillery Battalion (105mm)
152nd Airborne Anti-Aircraft Battalion (M2 Machine Gun and 57mm Anti-Tank gun)
Division Troops
127th Airborne Engineer Battalion
408th Airborne Quartermaster Company
11th Parachute Maintenance Company
711th Airborne Ordnance Company
221st Airborne Medical Company
511th Airborne Signal Company

The 11th Airborne Division ("Angels"^[1]) was a United States Army airborne formation, first activated on 25 February 1943, during World War II. Consisting of one parachute and two glider infantry regiments, with supporting troops, the division underwent rigorous training throughout 1943. It played a vital role in the successful Knollwood Maneuver, which was organized to determine the viability of large-scale American airborne formations after their utility had been called into question following a disappointing performance during the Allied invasion of Sicily.

Held in reserve in the United States for the first half of 1944, in June the division was transferred to the Pacific Theater of Operations. Upon arrival it entered a period of intense training and acclimatization, and by November was judged combat-ready. The 11th Airborne saw its first action on the island of Leyte in the Philippines, but in a traditional infantry role. In January 1945 the division took part in the invasion of Luzon. The two glider infantry regiments again operated as conventional infantry, securing a beachhead before fighting their way inland. The parachute infantry regiment was held in reserve for several days before conducting the division's first airborne operation, a combat drop on the Tagaytay Ridge. Reunited, the division participated in the Liberation of Manila, and two companies of divisional paratroopers conducted an audacious raid on the Los Baños internment camp, liberating two thousand civilians. The 11th Airborne's last combat operation of World War II was in the north of Luzon around Aparri, in aid of combined American and Philippine forces who were battling to subdue the remaining Japanese resistance on the island.

On 30 August 1945 the division was sent to southern Japan as part of the occupation force. Four years later it was recalled to the United States, where it became a training formation. One parachute infantry regiment was detached for service in the Korean War, but on 30 June 1958 the division was inactivated. It was briefly reactivated on 1 February 1963 as the 11th Air Assault Division (Test) to explore the theory and practicality of helicopter assault tactics, and was inactivated on 29 June 1965. The division's personnel and equipment were transferred to the newly raised 1st Cavalry Division (Airmobile).

World War II

Formation

Inspired by the pioneering German use of large-scale airborne formations during the Battle of France in 1940 and later the invasion of Crete in 1941,^[3] the various Allied powers decided to raise airborne units of their own.^[4] One of the resultant five American and two British airborne divisions,^[5]^[6] the 11th Airborne Division, was officially activated on 25 February 1943 at Camp Mackall in North Carolina, under the command of Major General Joseph Swing. As formed the division consisted of the 511th Parachute Infantry Regiment, the 187th Glider Infantry Regiment and the 188th Glider Infantry Regiment, and with a complement of 8,321 men was around half the strength of a regular U.S. infantry division of World War II.^[7]

The division initially remained in the United States for training, which in common with all airborne units was extremely arduous to befit their elite status.^[8] Training included lengthy forced marches, simulated parachute landings from {{convert|34|and|250|ft|m|adj=on}} towers, and practice jumps from transport aircraft; hesitancy in the doorway of an aircraft resulted in an automatic failure for the candidate. The washout rate was high, but there was never a shortage of candidates, especially because in American airborne units the rate of pay was much higher than that of an ordinary infantryman.^[8]

Before training was complete a debate developed in the U.S. Army over whether the best use of airborne forces was en masse or as small, compact units. On 9 July 1943, the first large-scale Allied airborne operation was carried out by elements of the U.S. 82nd Airborne Division and the British 1st Airborne Division in support of the Allied invasion of Sicily, code-named Operation Husky.^[9] The 11th Airborne Division's commanding general, Major General Swing, was temporarily transferred to act as airborne advisor to General Dwight D. Eisenhower for the operation, and observed the airborne assault which went badly. The 82nd Airborne Division had been inserted by parachute and glider and had suffered high casualties, leading to a perception that it had failed to achieve many of its objectives.^[10]

Swing Board

Eisenhower reviewed the airborne role in Operation Husky and concluded that large-scale formations were too difficult to control in combat to be practical.^[11] Lieutenant General Leslie J. McNair, the overall commander of Army Ground Forces, had similar misgivings: once an airborne supporter, he had been greatly disappointed by the performance of airborne units in North Africa and more recently Sicily. However, other high-ranking officers, including the Army Chief of Staff George Marshall, believed otherwise. Marshall persuaded Eisenhower to set up a review board and to withhold judgement until the outcome of a large-scale maneuver, planned for December 1943, could be assessed.^[12]

When Swing returned to the United States to resume command of the 11th Airborne in mid-September 1943, he was given the role of preparing the exercise.^[13] McNair ordered him to form a committee—the Swing Board—composed of air force, parachute, glider infantry, and artillery officers, whose arrangements for the maneuver would effectively decide the fate of divisional-sized airborne forces.^[10] As the 11th Airborne Division was in reserve in the United States and had not yet been earmarked for combat, the Swing Board selected it as the test formation. The maneuver would additionally provide the 11th Airborne and its individual units with further training, as had occurred several months previously in an earlier large-scale exercise conducted by the 101st

Knollwood Maneuver

The 11th Airborne, as the attacking force, was assigned the objective of capturing Knollwood Army Auxiliary Airfield near Fort Bragg in North Carolina.^[15] The force defending the airfield and its environs was a combat team composed of elements of the 17th Airborne Division and a battalion from the 541st Parachute Infantry Regiment.^[16] The entire operation was observed by Army Ground Forces commander Lt. Gen. McNair, who would ultimately have a significant say in deciding the fate of the parachute infantry divisions.^[17]

The Knollwood Maneuver took place on the night of 7 December 1943, with the 11th Airborne Division being airlifted to thirteen separate objectives by 200 C-47 Skytrain transport aircraft and 234 Waco CG-4A gliders.^[18] The transport aircraft were divided into four groups, two of which carried paratroopers while the other two towed gliders. Each group took off from a different airfield in the Carolinas. The four groups deployed a total of 4,800 troops in the first wave. Eighty-five percent were delivered to their targets without navigational error,^[18] and the airborne troops seized the Knollwood Army Auxiliary Airfield and secured the landing area for the rest of the division before daylight.^[18] With its initial objectives taken, the 11th Airborne Division then launched a coordinated ground attack against a reinforced infantry regiment and conducted several aerial resupply and casualty evacuation missions in coordination with United States Army Air Forces transport aircraft.^[18] The exercise was judged by observers to be a great success. McNair, pleased by its results, attributed this success to the great improvements in airborne training that had been implemented in the months following Operation Husky. As a result of the Knollwood Maneuver, division-sized airborne forces were deemed to be feasible, and Eisenhower permitted their retention.^[19]

Leyte

Following the Knollwood Maneuver the 11th Airborne remained in reserve until January 1944, when it was moved by train from Camp Mackall to Camp Polk in Louisiana. After four weeks of final preparation for its combat role,^[20] in April the division was moved to Camp Stoneman, California, and then transferred to Milne Bay, Papua New Guinea, between 25 May and 11 June.^[20] From June to September the division underwent acclimatization and continued its airborne training, conducting parachute drops in the New Guinea jungle and around the airfield in Dobodura. During this period, most of the glider troops became parachute-qualified making the division almost fully Airborne. On 11 November the division boarded a convoy of naval transports and was escorted to Leyte in the Philippines, arriving on 18 November.^[21] Four days later it was attached to XXIV Corps and committed to combat, but operating as an infantry division rather than in an airborne capacity. The 11th Airborne was ordered to relieve the 7th Infantry Division stationed in the Burauen-La Paz-Bugho area, engage and destroy all Japanese forces in its operational area, and protect XXIV Corps rear-area supply dumps and airfields.^[22]

Maj. Gen. Swing ordered the 187th Glider Infantry Regiment (GIR) to guard the rear installations of XXIV Corps, while the 188th GIR was to secure the division's rear and conduct aggressive patrols to eliminate any enemy troops in the area. The 511th Parachute Infantry Regiment (PIR) was assigned the task of destroying all Japanese formations in the division's operational area, which it began on 28 November when it relieved the 7th Infantry. The 511th PIR advanced overland with two battalions abreast and the third in reserve,^[23] but progress proved slow in the face of fierce Japanese resistance, a lack of mapped trails, and heavy rainfall (with more than twenty-three inches (60 cm) falling in November alone). As the advance continued resupply became progressively more difficult; the division resorted to using large numbers of Piper Cub aircraft to drop food and ammunition.^[24] Several attempts were made to improve the rate of advance, such as dropping platoons of the 187th GIR from Piper Cubs in front of the 511th PIR to reconnoiter, and using C-47 transport aircraft to drop artillery pieces to the regiment's location when other forms of transport, such as mule-trains, failed.^[25]

On 6 December the Japanese tried to disrupt operations on Leyte by conducting two small-scale airborne raids. The first attempted to deploy a small number of Japanese airborne troops to occupy several key American-held airfields at Tacloban and Dulag, but failed when the three aircraft used were either shot-down, crash-landed or destroyed on the ground along with their passengers.^[26] The second, larger, raid was carried out by between twenty-nine and thirty-nine transport aircraft supported by fighters; despite heavy losses, the Japanese managed to drop a number of airborne troops around Burauen airfield, where the headquarters of 11th Airborne Division were located.^[27]^[28] Five L-5 Sentinel reconnaissance aircraft and one C-47 transport were destroyed, but the raiders were eliminated by an ad hoc combat group of artillerymen, engineers and support troops led by Maj. Gen. Swing.^[29]

The 511th PIR was reinforced by the 2nd Battalion, 187th GIR, and continued its slow but steady progress. On 17 December it broke through the Japanese lines and arrived at the western shoreline of Leyte, linking up with elements of the 32nd Infantry Division.^[30] It was during this period that Private Elmer E. Fryar earned a posthumous Medal of Honor when he helped to repel a counterattack, personally killing twenty-seven Japanese soldiers before being mortally wounded by a sniper.^[31] The regiment was ordered to set up temporary defensive positions before being relieved on 25 December by the 1st Batt., 187th GIR, and the 2nd Batt., 188th GIR, who would themselves incur considerable casualties against a heavily dug-in enemy. The 511th PIR was reassembled at its original base-camp in Leyte on 15 January 1945.^[32]

Luzon

On 22 January the division was placed on alert for an operation on the island of Luzon, to the north of Leyte.^[29] Five days later the 187th and 188th Glider Infantry Regiments were embarked for Luzon by sea, while the 511th Parachute Infantry Regiment flew by C-46 Commando transport aircraft to Mindoro. At dawn on 31 January the 188th GIR led an amphibious assault near Nasugbu, in southern Luzon. Supported by a short naval barrage, A-20 Havoc light bombers and P-38 Lightning fighter aircraft, a beach-head was established in the face of light Japanese resistance.^[42] The regiment moved rapidly to secure Nasugbu, after which its 1st Battalion advanced up the island's arterial Highway 17 to deny the Japanese time to establish defenses further inland. The 2nd Battalion moved south, crossing the River Lian and securing the division's right flank.^[33] By 10:30 elements of the 188th had pushed deep into southern Luzon, creating the space for the 187th GIR to come ashore. The 188th's 2nd Battalion was relieved and the regiment continued its advance, reaching the River Palico by 14:30 and securing a vital bridge before it could be destroyed by Japanese combat engineers.

Following Highway 17 to Tumalin, the regiment began to encounter heavier Japanese resistance.^[34] At midnight the 187th took over the lead and the two glider infantry regiments rested briefly before tackling the main Japanese defensive lines. These consisted of trenches linked to bunkers and fortified caves, and were manned by several hundred infantry with numerous artillery pieces in support.^[35] At 09:00 on 1 February the glider infantry launched their assault, and by midday had managed to break through the first Japanese position; they spent the rest of the day conducting mopping up operations. On the morning of 2 February the second line was breached, and by midnight the 188th had broken a third. The divisional reconnaissance platoon was now in the vicinity of Tagaytay Ridge, the intended site of the 511th Parachute Infantry Regiment's first combat drop.^[36]^[37]

The 511th's airborne operation had originally been scheduled for 2 February, but with Major General Swing's insistence that the drop was only to go ahead if his ground forces were in range to offer support, the dogged Japanese resistance encountered delayed the operation.^[37] With only forty-eight C-47 Skytrain transport aircraft available, the 511th was forced to deploy in three waves. The regimental staff, the 2nd Battalion and half of the 3rd Battalion would drop first, the rest of the regiment would arrive in the second lift, and the 457th Parachute Field Artillery Battalion would drop in the third.^[38]

At 03:00 on 3 February the troops of the first lift entered their transport planes, and at 07:00 the first transports left Mindoro. Protected by an escort of P-61 Black Widow night fighters, on arriving over Luzon they followed Highway 17 to Tagaytay Ridge. The ridge itself was an open space some {{convert|2000|yd|m|spell=in}} long and {{convert|4000|yd|m|spell=in}} wide, plowed in places, and had been largely cleared of Japanese troops by local Filipino soldiers and recognized guerrillas.^[38] At 08:15 the first echelon of the first lift, approximately 345 men, successfully parachuted into the drop zone. The second echelon, consisting of approximately 570 men, were dropped prematurely and landed about {{convert|8000|yd|m|spell=in}} to the east. The next lift also encountered problems, with 425 men dropping correctly but another 1,325 dropping early due to pilot error and poor jump discipline.^[39] However, the entire regiment was assembled within five hours of the first landings.^[40] After overcoming minor Japanese resistance, by 15:00 the 511th had made contact with the 188th and 187th, and the entire division was once again assembled as a single formation. The ridge having been cleared of its remaining defenders, the division began to advance towards Manila, with the national highway in Silang, Dasmarinas, Imus and Bacoor where cleared by Fil-American Cavite Guerilla Forces FACGF under General Mariano Castaneda and reaching the Paranaque River by 21:00. The city was protected by the Genko Line, a major Japanese defensive belt that stretched along Manila's southern edge.^[41] The line consisted of approximately 1,200 two- to three-story deep blockhouses, many of which emplaced naval guns or large-caliber mortars. Entrenched heavy anti-aircraft weapons, machine-gun nests and booby-traps made of naval bombs completed the defenses, which were manned by around 6,000 Japanese soldiers.^[42]

The 11th Airborne Division was ordered to breach the Genko Line and drive into Manila, where it would link up with other American forces attacking the city from the north. All three regiments were committed to the assault.^[43] Spearheading the division's attack on 5 February, the 511th overcame fierce resistance and broke the crust of the Japanese position, but was soon relieved by the 188th. As the glider regiment took up the push westwards in the face of heavy opposition, the 511th changed their axis of advance and attempted to move into the city from the north. By 11 February, the division had penetrated as far as Nichols Field, an airfield that formed the center of the Genko Line. This was heavily fortified with a number of entrenched naval guns and a series of bunkers; after a short artillery bombardment on the morning of 12 February, the 187th's 2nd Battalion attacked the airfield's north-west corner while the 1st Battalion and the entire 188th regiment moved in from the south and south-eastern corners. This pincer movement succeeded in taking the airfield and, despite a local counter-attack, by nightfall the position was secured.^[44] The following day the division thrust towards Fort William McKinley, the headquarters of Rear Admiral Iwabuchi, commander of the Japanese defenders on Luzon. It was during this advance that Private First Class Manuel Perez Jr. neutralized several Japanese bunkers which were impeding the division's progress, capturing one single-handedly and killing eighteen Japanese soldiers. PFC Perez was posthumously awarded the Medal of Honor.^[45]

On 15 February, the 1st Battalion of the 187th, alongside other American units, launched an attack on Mabato Point. This was an extremely heavily fortified position featuring the same defensive measures as the Genko Line, and it would take six days of hard fighting, multiple airstrikes, and the frequent use of napalm and heavy artillery, before the point was secured.^[46] Meanwhile, having taken heavy casualties on its approach to Fort McKinley—particularly when the Japanese detonated a quantity of buried naval depth charges—on 17 February the rest of the 11th Airborne Division assaulted the fort. The 511th led the break-in, and by 18 February the area had been cleared of its defenders.^[47] Sporadic fighting continued in Manilla until 3 March, when all organized Japanese resistance ended.^[46]

Raid at Los Baños

A large number of civilian prisoners had been detained by the Japanese on Luzon, mostly in internment camps scattered throughout the island. The largest of these was located on the campus of the Agricultural College of the Philippines at Los Baños, some forty miles (64 km) south-east of Manila.^[48] General Douglas MacArthur had tasked the 11th Airborne Division with rescuing the Los Baños internees on 3 February, but the division's ongoing combat operations around the Genko Line left it unable to divert any resources at that time.^[49] All that could be accomplished during February was to gather information, primarily through liaison with the guerilla groups operating in Southern Luzon and around Los Baños. Maj. Gen. Swing and his command staff were briefed daily by the officer working with the guerilla groups, Major Vanderpool.^[49] From the guerillas and a few civilians that had escaped the camp, Vanderpool established that it was surrounded by two barbed-wire fences approximately six feet tall. Several guard towers and bunkers dotted its perimeter, each containing at least two guards. Prisoners left each morning under armed guard to gather food supplies and firewood from a nearby town.^[50] Vanderpool was informed that the camp's population consisted of American civilians in three distinct groups: Protestant missionaries and their families; Roman Catholic nuns and priests; and professional workers such as doctors and engineers, and their families. The latter group included several hundred women and children. While all the inmates appeared to be in good health, many had become weak from food rationing.^[51]

On 20 February, Maj. Gen. Swing was finally able to release sufficient troops for a raid on the Los Baños camp, and a four-phase plan was devised by Major Vanderpool and the divisional staff officers.^[52] The divisional reconnaissance platoon would travel across a nearby lake and move to the outskirts of the camp, securing a large adjacent field as the drop zone for a company of paratroopers. Having landed, the paratroopers would eliminate Japanese resistance in the area, secure the camp, and prepare for its evacuation. Fifty-four amphibious Amtracs would transport two additional companies of paratroopers to the lake shore, where a beachhead would be established while the Amtracs continued to the camp to evacuate its occupants. Simultaneously, a task force consisting of a reinforced infantry battalion, two battalions of heavy artillery and a tank destroyer battalion would advance down Highway 1 towards Los Baños to interdict any Japanese attempts to interfere.^[52]

Assisted by a group of guerrillas, on the night of 21 February the divisional reconnaissance platoon made their way to the lake and collected ten canoes. Despite navigational difficulties, the platoon came ashore near Los Baños at 02:00 the following morning, and after securing the paratroopers' drop zone, concealed themselves in the jungle near the camp.^[53] During the afternoon B Company of the 1st Battalion, 511th PIR was transferred to the airfield from which they would be deployed, while the rest of the battalion rendezvoused with the Amtrac convoy.^[54] At 07:00 on the morning of 23 February, B Company took off in ten C-47 Skytrain transport aircraft, arriving over their drop zone shortly afterwards.^[54] As the first paratroopers landed, the reconnaissance platoon and the supporting guerilla fighters opened fire on the camp's defences, using Bazooka rounds to penetrate the concrete pillboxes, and then entered the camp to engage its garrison. The paratroopers soon joined the battle, and by 07:30 the Japanese guards had been overcome and the internees were being rounded up and readied for evacuation.^[55] At the lakeshore the 511th's other two companies had secured their beachhead, and the convoy of Amtracs reached the camp without incident. Priority during loading was given to the women, children and wounded; some of the able-bodied men walked alongside the Amtracs as they returned to the beach. The first evacuation convoy left the camp at approximately 10:00, with B Company, the reconnaissance platoon and the guerrillas remaining behind to provide a rearguard. By 11:30 all of the civilians had been evacuated, and at 13:00 the Amtrac convoy returned for the rearguard, with the last paratroopers leaving the beach at approximately 15:00.^[56] Meanwhile, on Highway 1, the taskforce that had been deployed to protect the operation met heavy Japanese resistance and suffered several casualties, but was able to block Japanese forces that advanced on the camp, before retreating back to American lines.^[57] The raid had been a complete success, liberating 2,147 civilians.^[58]

Southern Luzon and Aparri

On the day that the Los Baños internees were freed, the headquarters of Sixth United States Army assigned the 11th Airborne Division the task of destroying all Japanese formations in southern Luzon, south of Manila.^[59] The bulk of the division moved south the following day, with the 187th GIR and the 511th PIR advancing abreast. The 188th GIR was detached from the main advance by Maj. Gen. Swing; it was to eliminate all Japanese units still operating in the Pico de Loro hills along the southern shore of Manila Bay.^[59] These forces belonged to the 80,000-strong Shimbu Group, one of three groups of the Japanese Fourteenth Area Army under General Tomoyuki Yamashita.^[60] It would take until the end of April for the 11th Airborne Division—often acting in conjunction with Filipino soldiers, the recognized guerillas and elements of the 1st Cavalry Division—to subdue the Shimbu Group. Conducting combat operations was extremely difficult in the mountainous terrain, and many Japanese units elected to fight to the death rather than surrender.^[59] However, all organized resistance in southern Luzon ended on 1 May, when the division captured Mount Malepunyo near the city of Lipa. The 11th Airborne established a base centered around the former Japanese airstrip on the outskirts of Lipa, the runway of which was lengthened by the 127th Airborne Engineer Battalion to accommodate C-47 transport aircraft. Once the engineering work was completed, the division's combat troops participated in several refresher-training courses.^[61]

The 11th Airborne's next operation took place on 23 June in the province of Aparri in northern Luzon.^[62] By this time the only Japanese forces remaining on the island were positioned to the far north and belonged to the 52,000-strong Shobu Group.^[62]^[63] This last of General Yamashita's three groups proved to be the most tenacious, forcing Lieutenant-General Walter Krueger, commander of the Sixth United States Army, to commit four infantry divisions, an armored task force, and a large band of the Filipino recognized guerrillas. While these forces pinned down the Japanese, the 37th Infantry Division began an advance northwards, defeating a weaker formation and encircling the main Japanese force. To ensure the success of the 37th's drive, Krueger called for an airborne force to land near Aparri and move southwards to meet the advancing 37th.^[64]

The 11th Airborne Division was to drop a battalion-sized combat team on Camalaniugan Airfield, approximately {{convert|10|mi|km|spell=in}} south of Aparri. It would then advance southwards, eliminating all Japanese resistance, until it linked up with the leading elements of the 37th Infantry Division.^[65] To accomplish this Maj. Gen. Swing formed a special unit–Gypsy Task Force–comprising the 1st Battalion of the 511th Parachute Infantry Regiment, G and I Companies of the regiment's 2nd Battalion, an artillery battery from the 457th Parachute Field Artillery Battalion, and a platoon of engineers and miscellaneous signal and medical detachments.^[66] Gypsy Task Force would be transported by fifty-four C-47 Skytrain and thirteen C-46 Commando aircraft, as well as six Waco CG-4A Gliders which would land jeeps and supplies for the task force.^[67] On 21 June, a detachment of pathfinders from the division was flown in to secure Camalaniugan Airfield, and two days later the transport aircraft carrying the troops of Gypsy Task Force were escorted by fighters to the area. At 09:00 the pathfinder detachment set off colored smoke to mark the drop-zone, but fierce winds and uneven ground around the airfield proved hazardous to the parachutists, causing two deaths and seventy injuries during the drop.^[68] Despite these casualties the force was rapidly concentrated, and began its advance southwards. Japanese resistance was stiff, forcing the airborne troops to rely on flamethrowers to eliminate bunkers and fortifications along their route.^[68] After three days of fighting and having eliminated a significant portion of Shobu Group, the task force encountered the lead elements of the 37th Infantry Division. Although Shobu Group would continue its resistance until September, its encirclement marked the 11th Airborne Division's final combat operation of the war.^[69]

Casualties

Post-World War II

Occupation of Japan

General MacArthur made plans to use the 11th Airborne Division in the invasion of Japan; it was to remain as Sixth Army's operational reserve, to be committed if required.^[71] However, with the end of hostilities in the Pacific Theater due to the surrender of Japan, the division was instead selected by General MacArthur to lead the American forces that would occupy Japan.^[72] The divisional staff received orders to this effect on 11 August 1945,^[73] and the division was transported to Okinawa on 12 August; an operation that involved 99 B-24 Liberator bombers, 350 C-46 Commando and 150 C-47 Dakota transport aircraft to airlift 11,100 men, 120 vehicles and approximately 1.16 million pounds (530,000 kg) of equipment.^[73] The 11th Airborne remained on Okinawa for several weeks before,^[74] on 28 August, it was ordered to land at Atsugi Airfield outside of Yokohama, on the main Japanese home island of Honshū. Its instructions were to secure the surrounding area, evacuate all Japanese civilians and military personnel within a radius of {{convert|3|mi|km|spell=in}}, and finally occupy Yokohama itself.^[73] A large number of C-54 Skymaster transport aircraft were made available, with the first—carrying Swing and his divisional staff—landing at Atsugi Airfield at 06:00 on 30 August.^[73] It took a week to fully assemble the division, and by 13 September it had been joined by the 27th Infantry Division, which was airlifted into Japan at the same time.^[75] The 11th Airborne Division was later moved from Yokohama to northern Japan, and established camps along the coast of Honshu and on the island of Hokkaido.^[76]

Training and first inactivation

Occupation duties in Japan continued until May 1949, when the 11th Airborne was relieved and recalled to the United States.^[77] The division was transferred to Camp Campbell in Kentucky^[77] and became a training formation, with several of its subordinate units inactivated including the 188th Glider Infantry Regiment. Training continued until the outbreak of the Korean War in 1950. For service in Korea, the 187th Glider Infantry Regiment—now renamed the 187th Airborne Infantry Regiment—and the 674th Airborne Field Artillery Battalion were detached from the division and re-formed as a separate Regimental Combat Team (RCT).^[77] The 187th RCT saw two years of fighting in Korea, conducting two airborne operations as well as operating as conventional infantry.^[78] The rest of the division continued its training role, processing and training approximately thirteen thousand recalled reservists between September and December 1950 alone.^[77] The 187th RCT remained in Korea until 1 October 1953, when it was transferred to Japan for two years until being replaced by the 508th RCT. The 187th returned to the United States on 17 July 1955, but as a unit independent of its parent division.^[79]

The 11th Airborne Division was sent to Germany in early 1956 as part of Operation Gyroscope, to replace the 5th Infantry Division stationed in Augsburg and Munich. As the division was en route, the 187th RCT was relocated to Fort Campbell, taking over the camps that the 11th had recently vacated. In July that year the 187th, along with the 508th ARC, was transferred to the newly reactivated 101st Airborne Division.

As the American Army began to restructure its organization (known as the Pentomic Concept), the battalions of the 187th were re-designated as Airborne Battle Groups. In early 1957 the 1st Airborne Battle Group, 187th Infantry transferred to Augsburg to join its former parent formation, where it was reintegrated into the 11th Airborne Division.^[80] The 2nd Airborne Battle Group, 187th Infantry remained with the 101st until 1964^[81] while the 3rd Battalion was inactivated.^[82] However, the 11th Division was itself inactivated in Augsburg on 1 July 1958, and the 1st Airborne Battle Group was instead moved to the 24th Infantry Division.^[83]

Reactivation (11th Air Assault Division) and inactivation

In the early 1960s, the United States Army began to explore alternative means for conducting future combat operations. One of the many ideas resulting from that effort was the concept of helicopter assault. To test this concept's feasibility, the 11th Airborne Division was reactivated on 1 February 1963 and renamed the 11th Air Assault Division (Test).^[84] This was done on the recommendation of the U.S. Army Tactical Mobility Requirements Board, also known as the 'Howze Board' after its president Lieutenant General Hamilton H. Howze.^[85]

The 11th never existed as a full division during the test period. Although the intent was to create three air assault brigades, the reality was an air assault brigade (which was also parachute-qualified), an airmobile brigade, and both ground and air artillery elements (the air artillery was provided by armed helicopters known as ARA). There was also an aviation group to control the helicopters assigned to the division -^[86] the 11th Aviation Group, consisting of the 227th, 228th, and 229th Aviation Battalions. Elements of its original combat units – the 187th Airborne Infantry, the 188th Airborne Infantry and the 511th Airborne Infantry were also reformed under the new division.^[84]^[87]

For the next two years, the 11th Air Assault Division developed and refined air assault tactics and the equipment required to operate effectively in the role. The 187th and 188th tested helicopters during various exercises, ranging from command and control maneuvers to scouting, screening and aerial resupply, to assess their ability to perform as combat aircraft.^[88] However, the division was inactivated for the final time on 29 June 1965. The colors and subordinate unit designations of the 1st Cavalry Division were transferred from its post in Korea to Fort Benning, Georgia, where they were used to reflag the 11th Air Assault Division into the 1st Cavalry Division (Airmobile). Concurrently, the personnel and equipment of the 1st Cavalry Division, which remained in Korea, were reflagged into the 2nd Infantry Division.^[89]^[90]

Air Assault Badge

An earlier predecessor to the current Air Assault Badge was worn by troops of 11th who qualified for it by making three helicopter rappels from {{convert|60|ft|m}} and three from {{convert|120|ft|m}}. Soldiers were also required to be knowledgeable of aircraft safety procedures; familiar with aircraft orientation; proficient in hand and arm signals and combat assault operations; able to prepare, inspect and rig equipment for external sling loads; and able to lash down equipment inside helicopters. The badge was first awarded in early 1964 and was only authorized for wear by soldiers within the 11th.{{Citation needed|date=May 2012}}