Fleet Landing Exercises

The history of amphibious warfare predates Greek antiquity. In United States history, early in the Revolution, Colonial marines were used to conduct amphibious landings and raids such as the Battle of Nassau, and the Penobscot Expedition. Amphibious operations were mounted in the American Civil War, and also prominently in the Spanish–American War. Though this history produced a system of landing procedures, the advent of the motor vehicle (the tank in particular) and the airplane required planners to think more critically about the feasibility of amphibious operations. In Panama, during the 1920s, the Marine Corps conducted a few modest experiments concerning modern amphibious warfare. At the beginning of the 1930s American defense policy shifted as the threat of the expansionist Japanese Empire became more apparent. The establishment of the Fleet Marine Force and greater concentration on the feasibility of amphibious assault were the direct result. Developing the ability to capture Japanese held islands during a Pacific war against Japan was a vital part of US war contingency plans; War Plan Orange. It was not until these contingency plans described the necessity of amphibious capability that testing key maneuvers in amphibious landings was funded. ==History==

After the First World War and until the mid-1930s, appropriations for the United States Navy were small. Ships fitted as troop transports were not priorities for the Navy in fact or in theory, so as a stop-gap measure the responsibility fell to battleships and cruisers to lift Marine landing forces. As a consequence of the standard davits on Navy ships, a length of 30’, the spacing of the davits fitted to these ships, and a weight of 5 tons (the maximum capacity of the davits) were imposed as basic requirements for all new landing craft Soon after the formation of the Fleet Marine Force, plans were made for training the FMF in landing operations in the Caribbean. The northwest peninsula of Culebra Island was chosen as the training area. The experimental problem used for the training involved a landing attack by the Fleet Marine Force embarked on Navy vessels moving from ship to shore in ship's boats and cutters. The Training Squadron consisted of the battleships Arkansas, Wyoming, and a destroyer squadron. In December 1934, a conference between Brigadier General C. H. Lyman of the Fleet Marine Force and Admiral C. S. Freeman was held aboard the flagship Trenton at St. Petersburg. Florida, to develop plans. The Marine contribution to the exercise included the 1st Marine Brigade, stationed at Quantico, composed of two infantry battalions, an artillery battery from the 10th Marine Regiment, and small engineer and service units. FLEX 1 The first of the exercises started 15 January on the beaches of Culebra and Vieques until March 15, 1935. The lift was provided by 18 ships' boats and one dumb barge artillery lighter. Fleet Landing Exercise Number 1 tested a series of theoretical and practical assumptions collected by the United States Marine Corps and Navy that soon became "Tentative Landing Operations Manual" of 1935. The exercises included landings, naval gunfire experiments, and the use of aviation in landing operations. Aircraft conducted aerial reconnaissance and bombardment sorties. The Caribbean fleet tested a range of weapons while the Marines moving from ship-to-shore employed machine guns, 81-mm mortars, and the 75-mm pack howitzers against beach targets. Due to the mixed results experienced with the boats used in the exercise, the Marines concluded that landing boat design needed to be improved. In one of the experiments, a boat was successfully covered in a protective smoke screen, but this caused the landing party to immediately halt, and the waves broke up the unit, while many boats lost their way to the beachhead. While the landing parties were ashore, the Navy held naval gunfire tests to assess the effects of different shells and fuses. These test concluded that area suppressing fire was far better than attempting pin-point bombardment. However, many supporting fire practices, both by aircraft and warships, were strictly limited due to safety precautions for the Marines conducting maneuvers along the beach. The outcome of these exercises convinced the Marines that better landing craft and boats were needed, as well as more dependable communications equipment and techniques. FLEX 2 The Fleet Landing Exercise Number 2 was conducted from January 4 to February 24, 1936, marking the beginning of the Culebra/Vieques Inner Range or the Culebra/Vieques Complex as it would be known until 1975 and the closing of the Culebra subranges. The amphibious exercises were transferred from Culebra's Flamenco Beach to Vieques, and naval gunfire practice began on Flamenco Beach and on the adjacent Flamenco Point. The 1st Brigade had revealed many of the same mistakes seen in FLEX1 but encountered several new problems. The Marines needed to get closer to the beach and the battleships were not able to tread in shallow waters. As for the landing craft boats, the problem was still not resolved as they were slow and extremely vulnerable. In several testing of various boats, they found that they proved to highly unstable for gun platforms, dangerous in disembarking the troops and were incapable in crossing submerged coral reefs. The uses of smoke and darkness to conceal the beach landings were still causing confusion amongst the landing parties. While the artificial naval gunfire tests were being continued, the rapid area fire had made the aerial spotting difficult for the pilots. And still communications were a problems. However, the barrage-type bombardment met the approval for the Army Officer-Observers to reinforce a fundamentally sound doctrine. They were criticized for lacking speed and maneuverability and being difficult to handle in surf. The Army's contribution climbed to three infantry regiments with supporting arms and brigade alternated in the part of landing force and shoreline defender. Brigadier General James Roosevelt, eldest son of the late President Franklin D. Roosevelt, who as a lieutenant colonel was in the Marine Corps Reserve on active duty aboard the during one of the reconnaissance patrols and experiments with raiding and patrolling parties. These raiding and patrolling parties would lay the ground work for the Marine Raider Bn. 1st Marine Brigade tested the concept of delivering 4-man patrols by submarines. The exercise missions were a mixed success at Vieques and Puerto Rico when two patrols were captured, but it was realized that with experience and refinement the concept held promise. The Vieques Phase, three patrols of one Army and two Marines with four men each were assigned by Rear Admiral A. W. Johnson, Commander of the Attack Force, in reaching the beach under the cover of darkness by inflatable rafts. They launched from submarines , and with intentions of conducting a reconnaissance ashore and return to the submarines the following night at certain appointed rendezvous. Four Marines from the Headquarters Company of the 1st Brigade marked the first amphibious reconnaissance patrol launching from a submarine by raft in United States history. Those four Marines reported aboard S-47 but was unsuccessful in locating the beach on Vieques. :"The weather conditions under which the night phase was carried on could not have been more adverse to a successful ship to shore movement. The heavy seas were awash the decks with every wave driven by a wind of between a force of 4 and 5 in velocity and varying direction from 70 degrees to 120 degrees which approximately paralleled the island. A brilliant full moon extended the visibility to at least , making a close approach to the beach impossible." This made it easy to discharge the patrols successfully to reach the beachhead without detection from the "enemy" zone of the Army National Guard. Although one was subsequently captured at the night of the landing. The tests in reconnaissance added that small, inflatable air rafts were feasible in transporting reconnaissance teams onto the beaches. However, both the landing teams and recon teams agreed that communications was still a major obstacle in achieving the total success of the Fleet Landing Exercises. Means of communications were important to transmit information quickly and not waiting for it to be relayed once the troops had landed for it to be available for those who would need it. FLEX 5 The Fleet Landing Exercise Number 5 commenced in January through March in 1938 and 1939 on the islands of Culebra and Vieques. These exercises again were only Navy-Marine Corps cooperation as the army no longer participated. The Marine Corps successfully landed amphibious reconnaissance patrols on Vieques when two such patrols disembarked from the during exercises from 13 January to 13 March 1939. Landing craft included two tank lighters, two artillery lighters, twenty-five special landing craft, of which twelve were the Bureau type, and eight landing skiffs. Comparative tests showed the Higgins Eureka landing craft, the 45-foot tank lighters, and rubber boats to have been the best adapted to landing operations. As a partial response to this problem, H.M. Smith seized the newly developed destroyer-transport. During FLEX 6, his plan called for the to land Company A, 1st Battalion, 5th Marines via rubber boats during the night, at H-minus three hours, at a point away from the primary assault beach. This force would advance inland, seize key terrain dominating the proposed beachhead, and thus protect the main landing from counter-attack. They were the first unit to use the revamped Manley. On 23 February 1940 it used rubber boats to execute an assault landing against Culebra. In 1940, patrols were successfully infiltrating ashore and reporting information and became an accepted doctrine in amphibious reconnaissance. FLEX 7 A year later, during Fleet Landing Exercise Number 7, Smith had three destroyer-transports. He designated the three companies of the 7th Marines embarked on these ships as the Mobile Landing Group. During the exercise these units again made night landings, either to protect the main assault, or conducted diversionary attacks. The 1st Marine Division was one of the first two division-sized units formed by the Corps. It was established in February 1941 aboard the in Cuba around the nucleus of the First Marine Brigade. The Division's first commander was the amphibious expert, Brigadier General Holland M. Smith. There is no record of an activation ceremony since the division was deeply involved the preparations for FLEX 7. This was the last fleet landing exercise before the United States became a combatant in the Second World War. ==Notes==