A most from the moment the first atomic bomb was dropped on Hiroshima, amphibious planners began searching for an improved concept of operations that simultaneously would eliminate troop concentrations in the beach area and yet would retain maximum impact against, and maximum movement in, the target area.
The problem of achieving mass while practicing dispersion essentially rested on an improved means of troop mobility, and to gain this, Marine Corps leaders soon chose the helicopter. After eight years of the most intense planning including thousands of field tests run under an extensive variety of nuclear and non-nuclear tactical situations, a new doctrine of amphibious warfare was published in Landing Force Bulletin-17 of December 1955. Cored around the technique of vertical envelopment, this doctrine dictates a powerful two-pronged attack, one prong a surface assault across the beach by conventional but dispersed means, the other a vertical envelopment by assault troops in helicopters.
The sine qua non of the new doctrine is helicopter operations. The old operational concept of the Amphibious Task Force working in conjunction with Fast Carrier and other naval forces remains, but certain conventional troop assault ships are to be replaced by helicopter-troop carriers from which assault elements of the Landing Force can be lifted and carried ten or more miles inland. Initial penetrations as far as a hundred miles from the Task Force or fifty miles inland and extending over divisional frontages of as much as fifty miles are considered feasible. The long-term goal is an all-helicopter assault with immediate post-assault elements coming in by aircraft.
To meet the present concept and to prepare for the future goal, the organization and structure of all Fleet Marine Force (FMF) units—three divisions, three air wings, and combat service elements (or Force Troops)—were rigorously reviewed from June to December 1956 by the "FMF Organization and Composition Board" headed by Major General (now Lieutenant General) Robert E. Hogaboom, USMC. The numerous and important recommendations of this group were approved by the Commandant, General Randolph McC. Pate, who ordered phase implementation commencing early in 1957. Reorganization of all units was completed in September, 1958.
The most vital changes in the FMF concerned the Marine infantry division. The new division is completely air-transportable with its assault elements completely helicopter- transportable. Reduced in personnel from 21,000 to just under 19,000, the division' has been stripped of much heavy equipment and some heavy weapons, yet by the incorporation of new but proven weapons and certain structural changes, it has actually increased in shock- and fire-power capability. Major changes are:
1) Command and staff personnel have been increased in order to maintain a division command post, an alternate command post, and an administrative command post. Regimental and battalion staffs have been reduced in size to meet the mobility requirement stemming from the regimental and battalion landing team concept of assault operations.
2) Certain administrative and supply personnel have been transferred from regimental headquarters to division headquarters and certain weapons such as the 4.2" mortar and the tank have been removed from the regiment. The result is a tactical regimental headquarters with maximum mobility in the field. Administrative and supply lines now run directly from division to battalion.
3) The weapons company in each battalion has been replaced by a fourth rifle company. Battalion weapons—a platoon of 106-mm. recoilless rifles, a platoon of 81-mm. mortars, a flame-thrower section and, for emergency purposes, eleven light machine guns and eight 3.5" rocket launchers—are now carried in the battalion H & S Company.
4) The division tank battalion has been transferred to Force Troops. It has been replaced with an anti-tank battalion equipped with 45 Ontos vehicles, a tracked carrier holding six 106-mm. recoilless rifles, each capable of killing any tank in existence or likely to be developed. The carrier itself is not helicopter-transportable but can be lifted easily by aircraft. The 106-mm. recoilless rifle detaches from the carrier and is easily lifted by helicopter for mounting on either the jeep or the new Mechanical Mule, an 800-pound, 27" high vehicle that can carry a 1,000- or 1,500-pound payload up to 25 mph.
5) The 155-mm. howitzer has been eliminated from the division artillery regiment. The new artillery regiment consists of an intermediate support battalion armed with the 105-mm. howitzer and three close support battalions armed with either the 105-mm. howitzer or the heavy mortar, the former helicopter-transportable by sectionalization, the latter as a single unit. Nuclear capability is furnished by close-support aircraft, by heavy artillery support battalions, and by ships firing rocket projectiles.
6) The division reconnaissance company has been increased to battalion strength.
The most controversial of these changes is perhaps that of removing tanks from the division. A number of Marine officers hold that the dual role of the tank in the assault, that of providing close fire support for the infantry plus protection against enemy armor, should not be sacrificed to logistic expediency. The proponents of the change argue that other weapons, for example air-to-surface missile systems and helicopter-borne close support artillery, will provide the necessary close support. As for protection against enemy armor, there are the 106-mm. recoilless rifle effective at 1,000 yards and the 3.5" rocket effective at 200 yards; in addition, greatly improved anti-tank weapons are now being tested. Furthermore, the bulk of future operations will probably be undertaken in reduced visibility or darkness and tanks are not very effective under such conditions. Finally, when the tactical situation demands tanks, they can be supplied from Force Troops just as can other heavy weapon units. Interestingly enough, the decision to remove the tanks did not rest on a logistic factor, but once the decision was made it was discovered that so much weight was eliminated as to allow the thought of a completely air-transportable division.
The most significant tactical change in the division is the replacement of the weapons company in each infantry battalion with a fourth rifle company in order to provide the increase in reconnaissance capability and in shock power which modern warfare dictates to the infantry battalion, the basic tactical unit of a Marine division. This battalion forms the core of the basic ground combat unit of the Marine Corps, the Battalion Landing Team or BLT. In a recent test exercise described by Lieutenant Colonel W. A. Wood, USMC, one BLT consisted of an infantry battalion, a 4.2' heavy mortar battery, a pioneer platoon, an AT (Ontos) platoon, a naval gunfire detachment and a medical detachment, altogether 61 officers and 1,390 enlisted men with a total of 116 vehicles and 108 radios—in other words a large and complex organization designed either for independent operations or for operations as part of a Regimental Landing Team. Since nuclear warfare imposes the probable requirement of frequent independent or dispersed operations, the BLT commander must have sufficient forces to attack in strength while simultaneously protecting his exposed flanks and rear and also to meet casualty and fatigue attrition over prolonged periods of isolated employment. Although increasing the size of the battalion by only one Marine officer, 58 Marine enlisted men, and eleven Navy enlisted men, the addition of the fourth rifle company, besides offering the tactical advantages derived from the quadrangular formation, offers the battalion commander nine more reinforced rifle squads, or 27 more fire teams, or 108 more scouts on security and reconnaissance tasks than could the old triangular battalion.
Some of the same reasons that prompted the addition of a fourth rifle company to each battalion prompted the increase of division reconnaissance from company to battalion strength. Extended, dispersed, and extremely mobile warfare automatically increases the intelligence demand, both because of the increased vulnerability of semi-isolated units to enemy action and because of the necessity of swift target acquisition to exploit the increased lethality of fire support weapons. The fivefold mission of the new reconnaissance battalion is to provide:
- Helicopter and ground reconnaissance beyond the combat area but short of distant reconnaissance missions;
- Flank, separation, and rear area reconnaissance;
- Road reconnaissance;
- Battlefield surveillance by establishment and displacement of helicopter-lifted observation posts;
- Counter reconnaissance.
The entire battalion is capable of being helicopter-lifted and a helicopter reconnaissance squadron has been provided in each Marine air wing for this purpose. Reconnaissance personnel are of course equally adept in conventional ground and amphibious reconnaissance techniques.
Extending division reconnaissance is the mission of a special reconnaissance company located in Force Troops. Consisting of an amphibious reconnaissance platoon, a parachute reconnaissance platoon, and a parachute pathfinder platoon, this company has a mission of preliminary operations in the assault area. Equipped for night operations in particular, the reconnaissance company is perfecting a number of new techniques that should satisfy the intelligence requirement peculiar to the vertical assault. In order to conduct deep reconnaissance, the parachute reconnaissance platoon is perfecting a technique of free fall jumping whereby, to gain pinpoint landing accuracy, a paratrooper falls free a considerable distance before opening his chute. The amphibious reconnaissance platoon has come up with an unconventional and highly successful technique that involves the SCUBA underwater breathing apparatus. So equipped and trained, personnel can embark and disembark from a submerged submarine, a method which eliminates the former hazard inherent in a submarine surfacing in an enemy area. The parachute pathfinder platoon consists of highly trained teams that as little as fifteen minutes prior to a scheduled helicopter assault will drop into the target area where they will establish communication with inbound helicopters. After guiding them to the best landing sites, members of the team will then provide fire security during initial deployment.
The major change in the fire support system of the division is found in the artillery regiment. By substituting the heavy mortar for the 105-mm. howitzer in the close support battalion for the vertical assault, and the 105 for the 155-mm. howitzer in the intermediate support battalion, the regiment has lost its former long-range destruction capability. But this sacrifice, a necessary one if the artillery is to support infantry in the assault, is not without compensations. One is the development of a greatly improved close support weapon, presumably a howitzer type capable of single helicopter lift, that has been designed to replace the heavy mortar. Another has resulted from the organizational and tactical promotion of the artillery battery to the basic fire support unit capable of operating independently (a position formerly held by the artillery battalion). By providing its own observation, communications, supply, and maintenance and by preparing its own firing data, the new battery offers a self-sufficient unit which can readily and simply absorb heavier support units that may be attached to it. This task organization capability extends upward to battalion and regimental level and means, in effect, an increased capability of offering the infantry unit heavy artillery from Force Troops and, in conjunction with infantry fire support centers, more effective naval gunfire and close-air support.
To exploit this tactical concept has meant a shift of emphasis in Force artillery to give it increased mobility and organizational flexibility necessary to permit rapid and smooth integration of its units into the division artillery regiment. Accordingly the battalion organization at Force level has been dropped; all Force artillery units are now organized as separate, independent batteries which will be either self propelled or helicopter-transportable and thus, once committed to the tactical area, able to go in and out of position in a matter of minutes. The potential here is tremendous. Both the Honest John and the Little John rocket batteries, the latter still under development, carry either nuclear or conventional warheads and are helicopter-transportable. Although the heavier batteries must be brought in by sea lift, the self-propelled 8" howitzer has tremendous power at an 18,000-yard range as does the self-propelled 155-mm. gun at 25,000 yards (and a self-propelled 155-mm. howitzer that is air-transportable is scheduled for delivery in 1961). The ability of these units to integrate rapidly and smoothly into the division artillery task organization concept, whether at regiment, battalion, or battery level, means that the division has very great power on call without the logistic responsibility of such power.
A final compensation for the division's loss of the howitzers has resulted from an increase in the capability of close air support by the addition of a second forward air controller (FAC) to each battalion's tactical air control party (TACP), and by the addition of a third Air Support Radar Team (ASRT) to the Marine air support squadron in the wing. The latter addition greatly increases the ability of the division to gain precise air delivery of nuclear weapons at any time and in any weather.
The service organization of the division has been streamlined by combining the old service regiment and the shore party battalion into one service battalion of 74 officers and 1,402 enlisted men which comprise an H & S company, three light support companies, one medium support company, and two landing support companies. The light support company—which, excepting ten 24-ton trucks, is helicopter-transportable—provides light supply and maintenance support to tactical elements of the division. The medium support company provides general support to the di vision as a whole and the two landing support companies assume the old shore party battalion function. The logistic capability of the battalion includes only those services habitually required by the division to initiate and sustain combat for the initial assault period. Extended division operations will require support from Force service elements, a capability that has been increased by the new Force service regiment which provides supply, maintenance, and essential services to a Marine division-wing task force as well as to a number of Force Troop units.
Other service changes in the division include a redesignation of the engineer battalion as the pioneer battalion, whose three pioneer companies and one pioneer support company can be augmented from Force service elements such as the Force engineer battalion, fixed and floating bridge companies, and explosive ordnance disposal company. Because of the additional mobility provided by the helicopter, the division motor transport battalion has lost one truck company but, when necessary, it can be reinforced by the motor transport battalion in Force Troops. The medical battalion of the division has lost two hospital companies and gained one collecting and clearing company, the reason being that new helicopter and transport aircraft evacuation techniques have rendered obsolete a division hospitalization requirement. Standing behind this battalion at Force level are separate surgical companies, hospital companies, dental companies, and the new mass evacuation company, a unit prepared to move immediately into any area that has received an atomic blast. This company provides the necessary personnel to control and direct operations at the site of the blast and a minimum of medical, monitoring, and decontamination personnel to perform essential tasks. A minimum force, it has been designed as an efficient core around which additional medical, damage control and rescue teams can immediately build.
Reorganization of the Marine air wing was not as drastic as that of the division. In strength the wing remains between 8-10,000 personnel with slightly less than 400 operational aircraft that form six major operational groups: Fighter (FJ-4 or Fury and F8U-1 or Crusader), Attack (A4D or Skyhawk and FJ-4B or Fury), All-Weather Fighter (F4D or Skyray), Fixed-wing Transport, Medium Helicopter, Light Helicopter, and one helicopter composite reconnaissance squadron. Besides their conventional missions of pre-assault bombardment, air protection, and close-air support of the Landing Force, the fighter and attack elements must now be concerned with tactics necessary to assault helicopter protection. Of predominant interest to the concept of vertical assault is the helicopter and transport lift capability of the wing.
The Marine Corps is currently flying four types of helicopters: the HOK, a small machine primarily used for reconnaissance, the HRS which is being replaced by the HUS, machines primarily employed as assault vehicles, and the HR2S, a larger machine primarily used for heavy lift. Included in each air wing are two light helicopter transport squadrons (HUS and HRS) or a total of 48 machines, one composite reconnaissance squadron (12 HOK and 12 HUS or HRS) Or a total of 24, and one medium helicopter transport squadron of 15 HR2S machines. The HUS is capable of carrying twelve troops with full equipment or 3,000 lbs. on a basis of a one hundred-mile operating radius; the HR2S can haul 26 troops with full equipment or 5,800 lbs. on a fifty-mile operating basis or twenty troops with full equipment or 4,500 lbs. on a one hundred-mile operating radius.
Helicopter assault techniques continue to be improved on a converted escort carrier, the training ship, USS Thetis Bay. The first true helicopter-troop carrier or LPH, the USS Iwo Jima, has been designed to berth 2,000 troops and carry more than 1,000 tons of cargo and approximately thirty HUS type helicopters—her keel was laid in March, 1959. To plug the necessary operational time gap, the USS Boxer has been converted into an interim LPH and is in service with Atlantic Fleet units at this time; another carrier, the USS Princeton, has undergone limited con version and is now serving with the Pacific Fleet. One other such carrier will probably be converted, but in any event the Fleet Marine Force now holds a two-battalion helicopter assault capability, a powerful weapon for any brushfire war that may involve this country. Complementing the LPH will be a new assault ship, the LPD.
Fixed-wing transport capability, now consisting of R4Q and R4D aircraft in the wing, will be greatly improved by the adoption of the C-130 aircraft which inter alia can carry 92 combat-loaded troops. Three squadrons of the C-130, each holding eighteen aircraft, are planned by the end of 1962 with the first squadron of an initial twelve aircraft being operational by the end of 1961. Each C-130 will be equipped with the Marine Inflight Refueling System (MIRS), a package device installed for a fighter refueling mission and removed for a troop-carrying mission.
The difficult problem of supporting helicopter and aircraft operations from the ground has been partially resolved by the development of a bulk fuel handling system that is helicopter-transportable and offers a fuel supply of 300,000 gallon capacity to the Landing Force. Tankers or smaller Landing Ship Tanks (LSTs) converted to tankers will pump the fuel through a buoyant hose to the beach where a system of five 60,000-gallon tank farms will carry it up to fifteen miles inland. An attendant problem of construction needs in the target area may have been whipped by a sectionalization program designed to make the three basic machines of assault construction—the bulldozer, scraper, and grader—helicopter-transportable. The Marine Corps now has prototypes of sectionalized pieces of these machines with no single piece weighing more than 6,000 lbs. and thus capable of lift in the HR2S, though not for long distances. In a demonstration last year a sectionalized bulldozer weighing 36,000 pounds was lifted by helicopter to a target area and assembled in two hours and forty-five minutes by eight Marines using hand tools.
These and other diverse problems are inherent in the doctrine of vertical envelopment just as problems are in any radical new operational concept. The pressing requirement for a better close support artillery weapon has been mentioned; improved helicopter protection is vital; a need for pinpoint accuracy of naval gunfire will exist so long as the conventional ship-to-shore landing phase is necessary; equally important is the development of equipment that will lighten the combat load of the individual Marine who today carries an average ninety pounds which is much too restrictive for the mobile role demanded of him. Budgetary limitations have dictated certain severe shortages to the Fleet Marine Force, and until a sufficient number of LPHs and helicopters become available, the Force is going to hold a limited helicopter assault capability. As Marine Corps planners point out, however, it was not long ago when the landing craft concept of the amphibious assault was developed without adequate landing craft, a difficulty that did not negate the validity of the concept. So in the last few years the Marine Corps has developed the concept of vertical assault despite material shortages. But, by the reorganization of its Fleet Marine Force units, by daily research and development of new weapons and equipment, by rotation of infantry battalions for operational training aboard the interim LPHs, the Marine Corps stands ready to exploit the necessary equipment upon its delivery.
Meanwhile the newly organized divisions, wings, and service elements are being tested in a variety of tactical situations. Minor changes are being made and another Organization and Composition Board will be convened in 1959 to review the present achievement. Although much remains to be accomplished, the recent reorganization, by fitting the Fleet Marine Force into the physical delimitations set by the vertical assault concept, has increased enormously its readiness for modern warfare.
Mr. Asprey is a free lance writer who has served tours of duty in the Marine Corps both during and after World War II. Since his retirement he has travelled abroad gathering material for articles published in a number of American magazines. He is the author of The Panther's Feast.