Fleet Landing Exercises
Encyclopedia
The Fleet Landing Exercises, or FLEX were a series of annual large-scale amphibious landings exercises conducted to test the United States Marine Corps
' legitimation of the Fleet Marine Force
. These exercises commenced between the periods of 1930—early 1940s.
in amphibious landings
that became proven in World War II
. There were many events of problems and mistakes but their importance was still significant. The joint-Navy and Marine Corps effort corrected many deficiencies, and improved many techniques. The FLEX were commenced by the 1st Marine Brigade of the East Coast, stationed at Quantico
composed of two infantry battalions, an artillery battery from the 10th Marine Regiment, small engineer and service units, and light cruiser
s and gunboat
s of the Special Service Squadron
. And 2nd Marine Brigade of the West Coast, where it was stationed at Marine Corps Base, San Diego
which was built around the 6th Marine Regiment assuming the same structure but greatly undermanned.
Even though the Guantanamo Bay Naval Base
played the preeminent role in the training and dispatching of Marines to several of these interventions. However, the islands around Puerto Rico, Culebra
and Vieques remained important in training and in preparing military personnel for the 1st Marine Brigade in the Caribbean
for the Fleet Landing Exercises. As distinct from the Outer Range, which is the open-sea range complex on 138000 square miles (357,418.4 km²) of ocean northeast and southeast of Puerto Rico and Vieques, as well as south of Puerto Rico. The Outer Range is used primarily for missile firings, both surface-to-air and air-to-air, as well as for fleet exercises. In the Pacific, the 2nd Marine Brigade stationed at Marine Corps Base San Diego
, California
was the first unit to engage in Pacific Fleet maneuvers, and from that point on the Fleet Marine Force
took part in each annual fleet problem. West Coast Marines made landings at San Clemente
, in the Hawaiian Islands
, and at Midway Atoll
.
Great achievements were made in analyzing the ship-to-shore movements and debarkation, varieties of air and naval gun fire
techniques, and communications equipment. Effortlessly the Marines had experimented with every amphibious technique discernible by touch and the tactical approachment of its limitations in equipment available. Most of the exercises were to include in day and night amphibious landings, concentrating assaults, dispersed infiltrations and amphibious reconnaissance
. Major improvements were due to practice of various methods in uses of landing craft
s while the acting raiding parties fired many variants of weapons. Through trial and error, the Fleet Marine Force adopted a new, refined doctrine in landing operations, the Fleet Training Publication 167.
The United States Navy
used old four smoke stacked World War I-era
destroyers converted for troop transport
by removing two of the stacks and its boilers, it allowed the space for the Marines and their equipment. This allowed further development in the loading techniques and quick debarkation that was required in an amphibious landing, although it greatly reduced the efficiency of the cargo in stow but allowed improvement in amphibious assault capabilities. The Navy re-designated the converted destroyers to APD classification.
and Vieques until March 15 in 1935. Fleet Landing Exercise Number 1 tested the doctrine outlined in the Tentative Manual and have included extensive landings, naval gunfire experiments, and use of aviation in landing operations, such as aerial reconnaissance
and bombardment. The Caribbean fleet have tested a large range of weapons while using the ship-to-shore movement in a wide spectrum of machine gun
s and 81-mm mortars
, and the 75-mm pack howitzers
against beach targets. The conclusion was that landing boats were needed to be improved, if not better, due to the mixed results. One of the exercises, a landing craft was successfully covered in a protective smoke screen but caused the landing party to immediately halt, and the waves broke up the party, while many boats lost their way to the beachhead. While the landing parties were ashore, the Navy held naval gunfire tests with assessing the effects of different shells and fuses. These test concluded that area fire was far more better than pin-point bombardment. However, many strafing practices both by the aviation and navy were strictly limited due to safety precautions for the Brigade conducting maneuvers along the beach. The outcome of these exercises have attested that better landing crafts and boats are adequately needed, as well as more technologically advanced communications equipment and techniques.
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 reef
s. 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. The Marine brigade gained tactical experience in the amphibious maneuvers ashore but the FLEX 2 had not made any significant breakthroughs in fixing the problems encountered during FLEX1.
from January 26 to March 3, 1937, in agreement with U.S. Attack Force Operation Plans 1-37 and 2-37. The 1st Marine Brigade was transferred to San Diego and was absorbed by the small-sized 2nd Marine Brigade, the whole Fleet Marine Force
and the understrength provisional Army
1st Expeditionary Brigade. And once again, the re-emergence of the testing problems of FLEX 1 and FLEX 2 were proven. The heavy Californian surf have proven that the landing boats were infeasible for beach landings; the Navy coxswains disembarked their troops to far from the beach, broached their boats, or were scattered in scouting out better, safer landing spots. It also proved conclusively that a special type landing boat with superior power, maneuverability, surf-riding qualities and protection was a highly desirable adjunct to the equipment for landing operations. The smoke and darkness continued huge problem as it did in earlier tests. Bombardment tests were extensive but the ordnance, communications and spotting techniques remained unsatisfactory because of the available equipment. The only significant improvements for the landing forces were the new Army Radios that became highly effective for communications and that the Marine pack howitzer batteries have shown that they can mobilize into the shore efficiently. Plus, they learned that aerial attacks had to be made at certain right angles to the direction of the attack to avoid friendly fire. The pilots however argued that they lacked the special-type of attack aircraft and the proper air-ground communications before they were to gain precision in strafing
and bombing. Two aircraft squadrons, from Quantico, VA. and North Island
, composed of the VF, VO, VB, and VJ aircraft. Also, the first time of cargo nets used for disembarking troops to the landing boats were a success, as in the past, the Marines were using the gangways.
The origins of the destroyer-transports
, or APDs were not widely known at that time until it was first mentioned in an after action report when Brigadier General
James J. Meade suggested destroyers might solve the dual problem of a shortage of amphibious transports and naval gunfire support. With such ships "troops could move quickly close into shore and disembark under protection of the ships' guns." The Navy apparently agreed and decided to experiment with one of its flush-deck, four-stack destroyers. It had built a large number of these during World War I and most were now in obsolete compared to the battleships that were being used as troop transports during those times. And he further concluded that the battleships can be pressed on to other naval missions instead of being relied for troop transportation. Although the APD provided lesser carrying capacity and limited ability in carrying landing crafts and heavy equipment. Of these various naval elements of APDs, the Navy detached Battleship Division One including the , , , which was being used as a mobile aerial bombing target configuration for Patrol Wing One. It became one of the victims at Pearl Harbor
five years later., and , Cruiser Divisions 4 & 5 including the , and , would later be lost on March 1, 1942 in the battle of Sundra Strait off the Netherlands East Indies
, and Destroyer Division 11. The total amphibious landing force was composed of approximately 4700 Army and Marine Corps personnel. Tragically, while firing a scheduled secondary battery practice on board the USS Wyoming on the last day of the exercises at San Clemente Island, an explosion occurred in the #13 5-inch gun mount, killing one officer and six enlisted personnel. Thirteen other personnel were injured in the blast.
, the Fleet Marine Force
returned to the Caribbean
to avoid any spying of the Japanese
. The tests were conducted on the beaches of Vieques and the main island of Puerto Rico
. During these exercises, three Army National Guard
regiments participated by staying ashore while the Marines of the 1st Brigade attempted a "mock" assault against them. It was the first time that reconnaissance
elements were added was first tested to reflect the reconnaissance doctrine outlined in the Fleet Training Publication 167. 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. 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 back 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 Puerto Rico Phase in the reconnaissance landing was however quite different. After sunset in the darkness, the submerged submarines navigated to 2 nautical miles (4 km) within the shoreline, following channels until it was able to reach within 1200 yards (1,097.3 m) from the beach of Ponce Playa
. 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.
It was again concluded that the landing force of the main landing parties were still in dispute over the landing crafts, but the tests in reconnaissance have added that the small, inflatable air rafts were feasible in transporting recon teams onto the beaches. However, both the landing teams and recon teams both agreed that communications was still a major deflection in achieving the total success of the Fleet Landing Exercises. Means of communications were important to transmit significant information quickly and not waiting for it to be relayed once the troops have landed for it to be available for those who would need it.
participate in the movement. The Marine Corps successfully landed amphibious reconnaissance patrols on Vieques during on when two partrols disembarked from the during the exercises from January 13 to March 13, 1939. The Navy reclassified Manley as a miscellaneous auxiliary (AG 28). After a few weeks of hasty work in the New York Navy Yard, the ship served as a transport for Marine units in the Caribbean. In the fall of 1939 Manley went back into the yards for a more extensive conversion. Workers removed all torpedo tubes, one gun, two boilers, and their stacks. That created a hold amidships for cargo and troops. Again, the Navy reclassified the Manley to a destroyer-transport class, APD-1. The Chief of Naval Operations made it a rush job so the ship would be available for FLEX 6 in early 1940.
Using experimental rubber boats, the inserted teams would deflated upon reaching the shore and reinflate to rendezvous with the awaiting submarine at a predestined point. As for the Marine assault teams they found that getting their equipment to the beachhead
during an amphibious landing and was a strenuous task and was extremely difficult with the landing craft
s. Most of the landing boats were incapable in hauling amphibious tractors, artillery
and other important supplies necessary for setting up an advanced base
. They requested the Naval
Bureau of Construction and Repair
for construction of feasible landing crafts but no avail and soon began to express interest in variety of different boats. Of all the other boats they had tested and researched, the Higgins' boats
became the best choice. When tested during the FLEX 5 by the Navy and Marine Corps, Higgins' Eureka boat surpassed the performance of the Navy-design. Although the drawback was that the equipment had to be unloaded, and men disembarked, over the sides, thus exposing them to enemy fire in a combat situation. They requested that the boat have retractable hinged door at its bow-replacing the machine gun mounts; and it was adopted as the standard personnel landing craft, the Landing Craft Vehicle Personnel (LCVP)
by 1940. Thus were two of the major impacts of San Clemente Island on the outcome of WWII, and our nation’s history.
could barely send two thousand Marines to land in the Caribbean
and only adequate experimental landing crafts were provided. 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 at H-minus three hours (prior to dawn) 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.
The 1st Marine Division was one of the first two division-sized unit ever formed by the Corps. It was established in February 1941 aboard the in Cuba
around the nucleus of the pre-war First Marine Brigade. The Division's first commander was the amphibious warrior, BrigGen Holland M. Smith. There was no record of an activation ceremony since the division was deep in the preparations for FLEX 7, the last of the pre-war fleet landing exercises.
United States Marine Corps
The United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...
' legitimation of the Fleet Marine Force
Fleet Marine Force
The United States Fleet Marine Forces are combined general and special purpose forces within the United States Department of the Navy that are designed in engaging offensive amphibious or expeditionary warfare and defensive maritime employment...
. These exercises commenced between the periods of 1930—early 1940s.
History
Although, similar exercises were commenced in the 1920s, it was not until the early 1930s that these contingency plans gave the envision of importance in testing key maneuversManeuver warfare
Maneuver warfare, or manoeuvre warfare , is the term used by military theorists for a concept of warfare that advocates attempting to defeat an adversary by incapacitating their decision-making through shock and disruption brought about by movement...
in amphibious landings
Amphibious warfare
Amphibious warfare is the use of naval firepower, logistics and strategy to project military power ashore. In previous eras it stood as the primary method of delivering troops to non-contiguous enemy-held terrain...
that became proven in World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. There were many events of problems and mistakes but their importance was still significant. The joint-Navy and Marine Corps effort corrected many deficiencies, and improved many techniques. The FLEX were commenced by the 1st Marine Brigade of the East Coast, stationed at Quantico
Marine Corps Base Quantico
Marine Corps Base Quantico, sometimes abbreviated MCB Quantico, is a major United States Marine Corps training base located near Triangle, Virginia, covering nearly in southern Prince William County, northern Stafford County, and southeastern Fauquier County...
composed of two infantry battalions, an artillery battery from the 10th Marine Regiment, small engineer and service units, and light cruiser
Cruiser
A cruiser is a type of warship. The term has been in use for several hundreds of years, and has had different meanings throughout this period...
s and gunboat
Gunboat
A gunboat is a naval watercraft designed for the express purpose of carrying one or more guns to bombard coastal targets, as opposed to those military craft designed for naval warfare, or for ferrying troops or supplies.-History:...
s of the Special Service Squadron
Special Service Squadron
The Special Service Squadron was a component of the United States Navy during the 1920s and 1930s.Under the United States Fleet, the squadron patrolled the Caribbean Sea as an instrument of gunboat diplomacy. It was headquartered in Balboa, Panama Canal Zone.-Commanders:* C.H. Hockson 1907 * Henry...
. And 2nd Marine Brigade of the West Coast, where it was stationed at Marine Corps Base, San Diego
San Diego, California
San Diego is the eighth-largest city in the United States and second-largest city in California. The city is located on the coast of the Pacific Ocean in Southern California, immediately adjacent to the Mexican border. The birthplace of California, San Diego is known for its mild year-round...
which was built around the 6th Marine Regiment assuming the same structure but greatly undermanned.
Even though the Guantanamo Bay Naval Base
Guantanamo Bay Naval Base
Guantanamo Bay Naval Base is located on of land and water at Guantánamo Bay, Cuba which the United States leased for use as a coaling station following the Cuban-American Treaty of 1903. The base is located on the shore of Guantánamo Bay at the southeastern end of Cuba. It is the oldest overseas...
played the preeminent role in the training and dispatching of Marines to several of these interventions. However, the islands around Puerto Rico, Culebra
Culebra, Puerto Rico
Isla Culebra is an island-municipality of Puerto Rico originally called Isla Pasaje and Isla de San Ildefonso. It is located approximately east of the Puerto Rican mainland, west of St. Thomas and north of Vieques. Culebra is spread over 5 wards and Culebra Pueblo...
and Vieques remained important in training and in preparing military personnel for the 1st Marine Brigade in the Caribbean
Caribbean
The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...
for the Fleet Landing Exercises. As distinct from the Outer Range, which is the open-sea range complex on 138000 square miles (357,418.4 km²) of ocean northeast and southeast of Puerto Rico and Vieques, as well as south of Puerto Rico. The Outer Range is used primarily for missile firings, both surface-to-air and air-to-air, as well as for fleet exercises. In the Pacific, the 2nd Marine Brigade stationed at Marine Corps Base San Diego
San Diego, California
San Diego is the eighth-largest city in the United States and second-largest city in California. The city is located on the coast of the Pacific Ocean in Southern California, immediately adjacent to the Mexican border. The birthplace of California, San Diego is known for its mild year-round...
, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
was the first unit to engage in Pacific Fleet maneuvers, and from that point on the Fleet Marine Force
Fleet Marine Force
The United States Fleet Marine Forces are combined general and special purpose forces within the United States Department of the Navy that are designed in engaging offensive amphibious or expeditionary warfare and defensive maritime employment...
took part in each annual fleet problem. West Coast Marines made landings at San Clemente
San Clemente, California
San Clemente is a city in Orange County, California. The population was 63,522 at the 2010 census. Located on the California Coast, midway between Los Angeles and San Diego at the southern tip of the county, it is known for its ocean, hill, and mountain views, a pleasant climate and its Spanish...
, in the Hawaiian Islands
Hawaiian Islands
The Hawaiian Islands are an archipelago of eight major islands, several atolls, numerous smaller islets, and undersea seamounts in the North Pacific Ocean, extending some 1,500 miles from the island of Hawaii in the south to northernmost Kure Atoll...
, and at Midway Atoll
Midway Atoll
Midway Atoll is a atoll in the North Pacific Ocean, near the northwestern end of the Hawaiian archipelago, about one-third of the way between Honolulu, Hawaii, and Tokyo, Japan. Unique among the Hawaiian islands, Midway observes UTC-11 , eleven hours behind Coordinated Universal Time and one hour...
.
Great achievements were made in analyzing the ship-to-shore movements and debarkation, varieties of air and naval gun fire
Naval gunfire support
Naval gunfire support is the use of naval artillery to provide fire support for amphibious assault and other troops operating within their range. NGFS is one of a number of disciplines encompassed by the term Naval Fires...
techniques, and communications equipment. Effortlessly the Marines had experimented with every amphibious technique discernible by touch and the tactical approachment of its limitations in equipment available. Most of the exercises were to include in day and night amphibious landings, concentrating assaults, dispersed infiltrations and amphibious reconnaissance
Reconnaissance
Reconnaissance is the military term for exploring beyond the area occupied by friendly forces to gain information about enemy forces or features of the environment....
. Major improvements were due to practice of various methods in uses of landing craft
Landing craft
Landing craft are boats and seagoing vessels used to convey a landing force from the sea to the shore during an amphibious assault. Most renowned are those used to storm the beaches of Normandy, the Mediterranean, and many Pacific islands during WWII...
s while the acting raiding parties fired many variants of weapons. Through trial and error, the Fleet Marine Force adopted a new, refined doctrine in landing operations, the Fleet Training Publication 167.
The United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
used old four smoke stacked World War I-era
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
destroyers converted for troop transport
High speed transport
High Speed Transports were converted destroyers and destroyer escorts used to support amphibious operations in World War II and afterward. They received the US Hull classification symbol APD; "AP" for transport and "D" for destroyer....
by removing two of the stacks and its boilers, it allowed the space for the Marines and their equipment. This allowed further development in the loading techniques and quick debarkation that was required in an amphibious landing, although it greatly reduced the efficiency of the cargo in stow but allowed improvement in amphibious assault capabilities. The Navy re-designated the converted destroyers to APD classification.
FLEX 1
The first of the annual exercises commenced on January 15 on the beaches of CulebraCulebra
Culebra may refer to:* Culebra, Puerto Rico, an island* Isla Culebra, the Spanish name of Sedge Island, part of the Falkland archipelago* Culebra Peak, the southernmost fourteener in Colorado, United States...
and Vieques until March 15 in 1935. Fleet Landing Exercise Number 1 tested the doctrine outlined in the Tentative Manual and have included extensive landings, naval gunfire experiments, and use of aviation in landing operations, such as aerial reconnaissance
Aerial reconnaissance
Aerial reconnaissance is reconnaissance that is conducted using unmanned aerial vehicles or reconnaissance aircraft. Their roles are to collect imagery intelligence, signals intelligence and measurement and signature intelligence...
and bombardment. The Caribbean fleet have tested a large range of weapons while using the ship-to-shore movement in a wide spectrum of machine gun
Machine gun
A machine gun is a fully automatic mounted or portable firearm, usually designed to fire rounds in quick succession from an ammunition belt or large-capacity magazine, typically at a rate of several hundred rounds per minute....
s and 81-mm mortars
M1 Mortar
The M1 is a United States 81 millimeter caliber mortar. It was used during World War II well into the 1950s when it was replaced by the lighter and longer ranged M29 Mortar...
, and the 75-mm pack howitzers
M116 howitzer
The 75mm Pack Howitzer M1 was designed in the United States in 1920s to meet a need for an artillery piece that could be moved across difficult terrain. The gun and carriage was designed so that it could be broken down into several pieces to be carried by pack animals...
against beach targets. The conclusion was that landing boats were needed to be improved, if not better, due to the mixed results. One of the exercises, a landing craft was successfully covered in a protective smoke screen but caused the landing party to immediately halt, and the waves broke up the party, while many boats lost their way to the beachhead. While the landing parties were ashore, the Navy held naval gunfire tests with assessing the effects of different shells and fuses. These test concluded that area fire was far more better than pin-point bombardment. However, many strafing practices both by the aviation and navy were strictly limited due to safety precautions for the Brigade conducting maneuvers along the beach. The outcome of these exercises have attested that better landing crafts and boats are adequately needed, as well as more technologically advanced communications equipment and techniques.
FLEX 2
The Fleet Landing Exercise Number 2 was conducted from January 4 to February 24 in 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 BeachFlamenco Beach
Flamenco Beach is a seaside resort in Puerto Rico, United States on the Island of Culebra.-Geography:Flamenco is located on the western shore of Culebra. The beach lies on a half-mile-wide, horseshoe strip of coast. The beach is bordered by the Culebra National Wildlife Refuge, which is of itself...
to Vieques, and naval gunfire
Naval gunfire support
Naval gunfire support is the use of naval artillery to provide fire support for amphibious assault and other troops operating within their range. NGFS is one of a number of disciplines encompassed by the term Naval Fires...
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 reef
Coral reef
Coral reefs are underwater structures made from calcium carbonate secreted by corals. Coral reefs are colonies of tiny living animals found in marine waters that contain few nutrients. Most coral reefs are built from stony corals, which in turn consist of polyps that cluster in groups. The polyps...
s. 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. The Marine brigade gained tactical experience in the amphibious maneuvers ashore but the FLEX 2 had not made any significant breakthroughs in fixing the problems encountered during FLEX1.
FLEX 3
The Fleet Landing Exercise Number 3 was conducted on San Clemente, CaliforniaCalifornia
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
from January 26 to March 3, 1937, in agreement with U.S. Attack Force Operation Plans 1-37 and 2-37. The 1st Marine Brigade was transferred to San Diego and was absorbed by the small-sized 2nd Marine Brigade, the whole Fleet Marine Force
Fleet Marine Force
The United States Fleet Marine Forces are combined general and special purpose forces within the United States Department of the Navy that are designed in engaging offensive amphibious or expeditionary warfare and defensive maritime employment...
and the understrength provisional Army
United States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...
1st Expeditionary Brigade. And once again, the re-emergence of the testing problems of FLEX 1 and FLEX 2 were proven. The heavy Californian surf have proven that the landing boats were infeasible for beach landings; the Navy coxswains disembarked their troops to far from the beach, broached their boats, or were scattered in scouting out better, safer landing spots. It also proved conclusively that a special type landing boat with superior power, maneuverability, surf-riding qualities and protection was a highly desirable adjunct to the equipment for landing operations. The smoke and darkness continued huge problem as it did in earlier tests. Bombardment tests were extensive but the ordnance, communications and spotting techniques remained unsatisfactory because of the available equipment. The only significant improvements for the landing forces were the new Army Radios that became highly effective for communications and that the Marine pack howitzer batteries have shown that they can mobilize into the shore efficiently. Plus, they learned that aerial attacks had to be made at certain right angles to the direction of the attack to avoid friendly fire. The pilots however argued that they lacked the special-type of attack aircraft and the proper air-ground communications before they were to gain precision in strafing
Strafing
Strafing is the practice of attacking ground targets from low-flying aircraft using aircraft-mounted automatic weapons. This means, that although ground attack using automatic weapons fire is very often accompanied with bombing or rocket fire, the term "strafing" does not specifically include the...
and bombing. Two aircraft squadrons, from Quantico, VA. and North Island
Naval Air Station North Island
Naval Air Station North Island or NAS North Island is located at the north end of the Coronado peninsula on San Diego Bay and is the home port of several aircraft carriers of the United States Navy...
, composed of the VF, VO, VB, and VJ aircraft. Also, the first time of cargo nets used for disembarking troops to the landing boats were a success, as in the past, the Marines were using the gangways.
The origins of the destroyer-transports
High speed transport
High Speed Transports were converted destroyers and destroyer escorts used to support amphibious operations in World War II and afterward. They received the US Hull classification symbol APD; "AP" for transport and "D" for destroyer....
, or APDs were not widely known at that time until it was first mentioned in an after action report when Brigadier General
Brigadier general (United States)
A brigadier general in the United States Army, Air Force, and Marine Corps, is a one-star general officer, with the pay grade of O-7. Brigadier general ranks above a colonel and below major general. Brigadier general is equivalent to the rank of rear admiral in the other uniformed...
James J. Meade suggested destroyers might solve the dual problem of a shortage of amphibious transports and naval gunfire support. With such ships "troops could move quickly close into shore and disembark under protection of the ships' guns." The Navy apparently agreed and decided to experiment with one of its flush-deck, four-stack destroyers. It had built a large number of these during World War I and most were now in obsolete compared to the battleships that were being used as troop transports during those times. And he further concluded that the battleships can be pressed on to other naval missions instead of being relied for troop transportation. Although the APD provided lesser carrying capacity and limited ability in carrying landing crafts and heavy equipment. Of these various naval elements of APDs, the Navy detached Battleship Division One including the , , , which was being used as a mobile aerial bombing target configuration for Patrol Wing One. It became one of the victims at Pearl Harbor
Pearl Harbor
Pearl Harbor, known to Hawaiians as Puuloa, is a lagoon harbor on the island of Oahu, Hawaii, west of Honolulu. Much of the harbor and surrounding lands is a United States Navy deep-water naval base. It is also the headquarters of the U.S. Pacific Fleet...
five years later., and , Cruiser Divisions 4 & 5 including the , and , would later be lost on March 1, 1942 in the battle of Sundra Strait off the Netherlands East Indies
Dutch East Indies
The Dutch East Indies was a Dutch colony that became modern Indonesia following World War II. It was formed from the nationalised colonies of the Dutch East India Company, which came under the administration of the Netherlands government in 1800....
, and Destroyer Division 11. The total amphibious landing force was composed of approximately 4700 Army and Marine Corps personnel. Tragically, while firing a scheduled secondary battery practice on board the USS Wyoming on the last day of the exercises at San Clemente Island, an explosion occurred in the #13 5-inch gun mount, killing one officer and six enlisted personnel. Thirteen other personnel were injured in the blast.
FLEX 4
The Fleet Landing exercise number 4 participated from January 13 to March 15 in 1938. As the world situation worsened World War IIWorld War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
, the Fleet Marine Force
Fleet Marine Force
The United States Fleet Marine Forces are combined general and special purpose forces within the United States Department of the Navy that are designed in engaging offensive amphibious or expeditionary warfare and defensive maritime employment...
returned to the Caribbean
Caribbean
The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...
to avoid any spying of the Japanese
Japanese people
The are an ethnic group originating in the Japanese archipelago and are the predominant ethnic group of Japan. Worldwide, approximately 130 million people are of Japanese descent; of these, approximately 127 million are residents of Japan. People of Japanese ancestry who live in other countries...
. The tests were conducted on the beaches of Vieques and the main island of Puerto Rico
Puerto Rico
Puerto Rico , officially the Commonwealth of Puerto Rico , is an unincorporated territory of the United States, located in the northeastern Caribbean, east of the Dominican Republic and west of both the United States Virgin Islands and the British Virgin Islands.Puerto Rico comprises an...
. During these exercises, three Army National Guard
Army National Guard
Established under Title 10 and Title 32 of the U.S. Code, the Army National Guard is part of the National Guard and is divided up into subordinate units stationed in each of the 50 states, three territories and the District of Columbia operating under their respective governors...
regiments participated by staying ashore while the Marines of the 1st Brigade attempted a "mock" assault against them. It was the first time that reconnaissance
Reconnaissance
Reconnaissance is the military term for exploring beyond the area occupied by friendly forces to gain information about enemy forces or features of the environment....
elements were added was first tested to reflect the reconnaissance doctrine outlined in the Fleet Training Publication 167. 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
Brigadier general (United States)
A brigadier general in the United States Army, Air Force, and Marine Corps, is a one-star general officer, with the pay grade of O-7. Brigadier general ranks above a colonel and below major general. Brigadier general is equivalent to the rank of rear admiral in the other uniformed...
James Roosevelt
James Roosevelt
James Roosevelt was the oldest son of U.S. President Franklin D. Roosevelt. He was a United States Congressman, an officer in the United States Marine Corps, an aide to his father, the official Secretary to the President, a Democratic Party activist, and a businessman.-Early life:Roosevelt was...
, eldest son of the late President Franklin D. Roosevelt
Franklin D. Roosevelt
Franklin Delano Roosevelt , also known by his initials, FDR, was the 32nd President of the United States and a central figure in world events during the mid-20th century, leading the United States during a time of worldwide economic crisis and world war...
, who as a Lieutenant Colonel
Lieutenant Colonel (United States)
In the United States Army, United States Air Force, and United States Marine Corps, a lieutenant colonel is a field grade military officer rank just above the rank of major and just below the rank of colonel. It is equivalent to the naval rank of commander in the other uniformed services.The pay...
was in the Marine Corps Reserve on active duty aboard the during one of the reconnaissance patrols and experiments with raiding and patrolling parties. 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
Rear admiral (United States)
Rear admiral is a naval commissioned officer rank above that of a commodore and captain, and below that of a vice admiral. The uniformed services of the United States are unique in having two grades of rear admirals.- 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 back 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 [knots] 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 1500 yards (1,371.6 m), making a close approach to the beach impossible."
The Puerto Rico Phase in the reconnaissance landing was however quite different. After sunset in the darkness, the submerged submarines navigated to 2 nautical miles (4 km) within the shoreline, following channels until it was able to reach within 1200 yards (1,097.3 m) from the beach of Ponce Playa
Ponce, Puerto Rico
Ponce is both a city and a municipality in the southern part of Puerto Rico. The city is the seat of the municipal government.The city of Ponce, the fourth most populated in Puerto Rico, and the most populated outside of the San Juan metropolitan area, is named for Juan Ponce de León y Loayza, the...
. This made it easy to discharge the patrols successfully to reach the beachhead
Beachhead
Beachhead is a military term used to describe the line created when a unit reaches a beach, and begins to defend that area of beach, while other reinforcements help out, until a unit large enough to begin advancing has arrived. It is sometimes used interchangeably with Bridgehead and Lodgement...
without detection from the "enemy" zone of the Army National Guard. Although one was subsequently captured at the night of the landing.
It was again concluded that the landing force of the main landing parties were still in dispute over the landing crafts, but the tests in reconnaissance have added that the small, inflatable air rafts were feasible in transporting recon teams onto the beaches. However, both the landing teams and recon teams both agreed that communications was still a major deflection in achieving the total success of the Fleet Landing Exercises. Means of communications were important to transmit significant information quickly and not waiting for it to be relayed once the troops have landed for it to be available for those who would need it.
FLEX 5
The Fleet Landing Exercise Number 5 commenced on January through March in 1938 and 1939 on the islands of Culebra and Vieques. These exercises again became only Navy-Marine Corps cooperation as they no longer had the United States ArmyUnited States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...
participate in the movement. The Marine Corps successfully landed amphibious reconnaissance patrols on Vieques during on when two partrols disembarked from the during the exercises from January 13 to March 13, 1939. The Navy reclassified Manley as a miscellaneous auxiliary (AG 28). After a few weeks of hasty work in the New York Navy Yard, the ship served as a transport for Marine units in the Caribbean. In the fall of 1939 Manley went back into the yards for a more extensive conversion. Workers removed all torpedo tubes, one gun, two boilers, and their stacks. That created a hold amidships for cargo and troops. Again, the Navy reclassified the Manley to a destroyer-transport class, APD-1. The Chief of Naval Operations made it a rush job so the ship would be available for FLEX 6 in early 1940.
Using experimental rubber boats, the inserted teams would deflated upon reaching the shore and reinflate to rendezvous with the awaiting submarine at a predestined point. As for the Marine assault teams they found that getting their equipment to the beachhead
Beachhead
Beachhead is a military term used to describe the line created when a unit reaches a beach, and begins to defend that area of beach, while other reinforcements help out, until a unit large enough to begin advancing has arrived. It is sometimes used interchangeably with Bridgehead and Lodgement...
during an amphibious landing and was a strenuous task and was extremely difficult with the landing craft
Landing craft
Landing craft are boats and seagoing vessels used to convey a landing force from the sea to the shore during an amphibious assault. Most renowned are those used to storm the beaches of Normandy, the Mediterranean, and many Pacific islands during WWII...
s. Most of the landing boats were incapable in hauling amphibious tractors, artillery
Artillery
Originally applied to any group of infantry primarily armed with projectile weapons, artillery has over time become limited in meaning to refer only to those engines of war that operate by projection of munitions far beyond the range of effect of personal weapons...
and other important supplies necessary for setting up an advanced base
Advanced Base Force
The United States Marine Corps's Advanced Base Force was a coastal and naval base defense force that was designed to set up mobile and fixed bases in the event of major landing operations within, and beyond, the territorial United States...
. They requested the Naval
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
Bureau of Construction and Repair
Bureau of Construction and Repair
The Bureau of Construction and Repair was the part of the United States Navy which from 1862 to 1940 was responsible for supervising the design, construction, conversion, procurement, maintenance, and repair of ships and other craft for the Navy...
for construction of feasible landing crafts but no avail and soon began to express interest in variety of different boats. Of all the other boats they had tested and researched, the Higgins' boats
LCVP
The Landing Craft, Vehicle, Personnel or Higgins boat was a landing craft used extensively in amphibious landings in World War II. The craft was designed by Andrew Higgins of Louisiana, United States, based on boats made for operating in swamps and marshes...
became the best choice. When tested during the FLEX 5 by the Navy and Marine Corps, Higgins' Eureka boat surpassed the performance of the Navy-design. Although the drawback was that the equipment had to be unloaded, and men disembarked, over the sides, thus exposing them to enemy fire in a combat situation. They requested that the boat have retractable hinged door at its bow-replacing the machine gun mounts; and it was adopted as the standard personnel landing craft, the Landing Craft Vehicle Personnel (LCVP)
LCVP
The Landing Craft, Vehicle, Personnel or Higgins boat was a landing craft used extensively in amphibious landings in World War II. The craft was designed by Andrew Higgins of Louisiana, United States, based on boats made for operating in swamps and marshes...
by 1940. Thus were two of the major impacts of San Clemente Island on the outcome of WWII, and our nation’s history.
FLEX 6
Fleet Landing Exercise Number Six was the first wartime exercise in amphibious training in 1940-1941. It became clear that the Navy and Marine Corps was in dire need for amphibious transports larger than destroyers as the 1st Brigade1st Brigade
1st Brigade can refer to numerous military formations, usually with long traditions, in various countries. They include:-Canada:* 1st Canadian Armoured Brigade* 1 Canadian Mechanized Brigade Group* 1st Canadian Tank Brigade-Japan:...
could barely send two thousand Marines to land in the Caribbean
Caribbean
The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...
and only adequate experimental landing crafts were provided. 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 at H-minus three hours (prior to dawn) 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
Culebra
Culebra may refer to:* Culebra, Puerto Rico, an island* Isla Culebra, the Spanish name of Sedge Island, part of the Falkland archipelago* Culebra Peak, the southernmost fourteener in Colorado, United States...
. 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 to protect the main assault, or conducted diversionary attacks.The 1st Marine Division was one of the first two division-sized unit ever formed by the Corps. It was established in February 1941 aboard the in Cuba
Cuba
The Republic of Cuba is an island nation in the Caribbean. The nation of Cuba consists of the main island of Cuba, the Isla de la Juventud, and several archipelagos. Havana is the largest city in Cuba and the country's capital. Santiago de Cuba is the second largest city...
around the nucleus of the pre-war First Marine Brigade. The Division's first commander was the amphibious warrior, BrigGen Holland M. Smith. There was no record of an activation ceremony since the division was deep in the preparations for FLEX 7, the last of the pre-war fleet landing exercises.