MARINE CORPS AIRBORNE DOCTRINE
On May 15, 1940, the Commandant, Gen Thomas Holcomb, wrote the Chief of Naval Operations to seek the help of his naval attaches in gathering information on foreign parachute programs. He noted that he was intensely interested in the subject. The Berlin attaché responded the following month with a lead on how to obtain newsreels and an educational film on the German paratroopers. The London attaché eventually provided additional information on the Germans and on Britain’s fledgling parachute program launched in June 1940. The Commandant’s own intelligence section had already compiled available material on the German and Soviet forces.
The report noted the distinction between parachutists and air infantry, the latter consisting of specially organized units trained and equipped to move by transport aircraft. The paratroopers acted as the advance guard for the air infantry by seizing the airfields upon which the transports would land. The report also detailed the different methods that the Germans and Soviets used to train their respective forces.
German paratrooper recruits went through an intensive ground school prior to making the six jumps required to achieve membership in a unit. The Soviet program featured the use of towers for practice jumps prior to actual training with a plane. When staff officers at Headquarters first looked at parachute forces in the aftermath of Fort Eben Emael in Belgium, they specifically considered the functions such a unit would perform. Their ideas were generally similar: paratroopers would be valuable for raids; for reconnaissance; for the seizure of airfields; for the aerial envelopment of the enemy’s rear area and, finally, for the occupation of key terrain in advance of the main force. Several officers specifically tied the latter two missions to the conduct of amphibious operations. Although the Corps’ amphibious doctrine had existed on paper for several years, the Fleet Marine Force was having a difficult time turning those ideas into reality.
During annual exercises, a lack of decent landing craft and transports had prevented the rapid buildup ashore of combat power, something the amphibious force had to do if it hoped to defeat counterattacks against its beachhead. Gen Holland M. Smith, commander of the 1st Marine Brigade, first tried to solve this problem during Fleet Exercise 6 in February 1940. A key part of his plan was the night landing of one company three hours prior to the main amphibious assault. This company embarked on a fast destroyer transport, would go ashore by rubber boat, seize key terrain overlooking the proposed beachhead, and then protect the rest of the force as it landed and got itself organized. This idea eventually gave birth to the 1st Marine Raider Battalion.
In the spring of 1940, it was obvious to a number of Marine officers, at Headquarters and in the FMF, that parachutism now constituted an ideal alternative for speedily seizing a surprise lodgment on an enemy coast. Smith explicitly would advocate that new wrinkle to doctrine the following year. The Marine Corps did not develop formal airborne doctrine until late 1942. It came in the form of a 12-page manual titled Parachute and Air Troops. Its authors believed that airborne forces could constitute a paralyzing application of power in the initial phase of a landing attack. Secondarily, parachute troops could seize critical points, such as airfields or bridges, or they could operate behind enemy lines in small groups to gather intelligence or conduct sabotage operations.
The doctrinal publication did not provide much detail on tactics, but the parachutists worked out techniques in combination with Marine transport pilots. The standard method of operations called for a terrain-hugging approach flight at altitudes as low as 50 feet, with a last-minute ascent to several hundred feet, at which point the jumpers exited the aircraft. The doctrine noted the limitations of airborne assault and emphasized that these forces could only seize small objectives and hold them for a short time pending linkup with seaborne or overland echelons.
The manual envisioned the formation of an air brigade composed of one regiment each of paratroops and air infantry, the type of force originally sought by Holland Smith. All leaders were thoroughly briefed beforehand with maps, aerial photos, and a sand table mockup of the objective so that they could quickly get organized and oriented once they hit the ground. When they jumped, the paratroopers carried the collapsible Johnson weapons or the Reisings, along with basic individual items such as a belt, knife, canteens, and ammunition. Cargo parachutes delivered heavier weapons and supplies. From early in the life of the program, planners realized that a lack of training facilities and planes hampered the ability of the Corps to field an adequate airborne force. They thus began looking at using parachutists for secondary missions.
In April 1941 the Commandant directed that parachute units conduct training in rubber boat operations, reconnaissance, demolitions, and other subjects to enable them to conduct special missions requiring only small forces or not necessarily involving airborne insertion. On New Caledonia in 1943, the 1st Parachute Regiment devoted much of its training time to such skills. In many respects, the Marine Corps had molded the parachutists and raiders into carbon copies of each other, with the parachutists’ unique ability to enter battle being the only significant difference between the two special units.
AIR TRANSPORT
The fate of the parachute program was intertwined completely with Marine aviation, inasmuch as the airborne infantry could not fulfill its function without transport aircraft. Although men could jump from just about any type of plane, tactical parachute operations required certain characteristics in aircraft. The door had to allow easy exit and the interior freedom of movement so that a stick of jumpers could exit the plane in short order; the ideal was one second per man. Any increase in the delay between jumpers resulted in wide dispersion once the stick landed on the ground and that translated into extra time spent in finding weapons and getting organized to fight. The last parachutists also might find themselves landing outside the drop zone in woods or water, either of which could easily result in death or serious injury.
When Headquarters planners first began evaluating the idea of creating Marine parachute units, the Corps possessed just two planes suitable for tactical jumping, the pair of Douglas R2D-1s (Military version of the DC-2) of Utility Squadron 1 (VMJ-1) in Quantico (Virginia). Its two Wright engines generated 710 horsepower, lifted the plane’s maximum gross weight of 18.200 pounds, and pushed it to a top speed of 210 miles per hour. It could accommodate approximately 10 parachutists. The capacity depended, of course, upon the amount of equipment to be dropped, since each cargo parachute for weapons and supplies took up the space of one man. At that time the Department of the Navy had on order seven of Douglas’ newer DC-5s, known as R3D-2s in the naval services. The Marine Corps was slated to receive four of these aircraft, which could hold about 15 jumpers. Finally, the Corps had its R3D-2s by mid-1941 and placed two each in VMJ-252 and 152, respectively located in Hawaii and Quantico. One of the old R2D-1s remained in service at the air station in San Diego.
The real workhorse of Allied airborne operations during World War II was based on Douglas’ DC-3 airliner, which made its first commercial flight in 1935. The Army Air Forces began buying a military version in 1940 and labeled it the C-47. The Department of the Navy acquired its first planes of this type, designated the R4D, during 1942. The Skytrain’s two Pratt and Whitney engines generated 1200 horsepower, lifted the plane’s gross weight of 29.000 pounds, and pushed it to a top speed of 227 miles per hour. It could carry up to 25 paratroopers out to a range of 1600 miles. The United States built over 10.000 C-47 variants during the war, with the naval services receiving 568 of them. In August 1943, the Marine Corps possessed about 80 of these planes. There were seven VMJ squadrons and an eighth on the drawing board, each with a projected authorization of one dozen R4Ds, but most of the units were brand new and still short of planes and crews. A number of the aircraft also were distributed in ones or twos to headquarters squadrons in support of various air groups. The heart of Marine transport capability rested at that point in Marine Air Group 25’s three squadrons in the South Pacific, a grand total of just 36 transports.
TRAINING CENTERS
Very early in the process of creating the parachute program, the Marine Corps sought out information on the parachute tower then being used as an amusement ride at the New York City World’s Fair. A lieutenant with the Marine Detachment at the fair provided his report on May 20, 1940. He thought such a tower could be used to advantage if the Corps modified it to simulate the physical jolt that a jumper would experience when his parachute opened and radically slowed his rate of descent. The Safe Parachute Manufacturing Company, the builder of the World’s Fair ride, also owned two towers at Hightstown (New Jersey). Each stood 150 feet tall and used a large ring to lift a spread parachute with the jumper dangling from the risers. When the mechanism released its load, the descending chute automatically filled with air. One tower featured a controlled descent guided by four cables, while the other completely released the parachute for a free fall. Fortuitously, Hightstown was just 20 miles from the Navy’s Parachute Material School at the Naval Air Station Lakehurst (New Jersey), the facility that trained sailors and a handful of Marines to pack parachutes for pilots. That made Lakehurst the obvious choice as the primary instruction facility. Lakehurst eventually had room to train a maximum of 100 men at a time. Given the length of the course (which often stretched to six weeks or more due to delays because of bad weather, the Marine Corps could produce no more than 700 qualified parachutists per year.
By mid-1941 the school was not even achieving that pace, having fallen more than two months behind schedule. In July 1941, the officer in charge of the school recommended the creation of an additional parachute training facility at the burgeoning Marine base in New River (North Carolina), but it would be a while before the Corps found the resources to act on that suggestion. In the meantime, Headquarters decided to shift its primary parachute school to San Diego to allow more efficient use of training time due to better weather and the proximity of Marine aviation units.
In April 1942, the Lakehurst detachment began transferring its instructors to San Diego, a process completed in May after the last Lakehurst class graduated. The new San Diego school began training its first class on May 27. The plan called for the program to start a new class of 36 students each week, with a possible expansion to 60 trainees per week in the future. The school initially operated out of San Diego‘s Camp Elliott, but the Corps built barracks, jump towers, plane mockups, and aviation fields near Santee and moved the entire operation there at the end of August 1942. The Commandant named this small base, dedicated entirely to parachute training, Camp Gillespie (California) in honor of Brevet Maj Archibald H. Gillespie, who had participated in the campaign to free California from Mexico in 1846.
The Marine Corps established another training facility at New River‘s Hadnot Point in 1942. In June the 1st Parachute Battalion had transferred one officer and 13 NCOs to form the instructor cadre. The school opened with the first class of 54 students on August 10, but delays in constructing the jump towers and obtaining parachutes slowed training. The initial group finally graduated on October 13. The New River school’s designed capacity was 75/class, with a new class beginning every week. By the end of 1942, the Marine parachute program was finally in full swing and capable of producing 135 new jumpers per week, though actual numbers were never that high. The Marine Corps had one more source of trained parachutists. During the 1st Battalion’s initial period of recuperation from fighting on Gavutu and Guadalcanal, it had difficulty obtaining qualified jumpers from the States. To solve the problem, Col Williams organized his own informal school. It lacked towers and he ignored much of the syllabus used stateside, but during the program’s brief operation it produced about 100 trained jumpers from volunteers garnered from other units located in New Caledonia.