Military

LCAC And The Over-The-Horizon Amphibious Assault

 

CSC 1985

 

SUBJECT AREA Warfighting

 

 

                       EXECUTIVE SUMMARY

 

TITLE:   LCAC AND THE OVER-THE-HORIZON AMPHIBIOUS ASSAULT

 

I.  Purpose:  To develop a concept for using the Landing

 

Craft Air Cushion (LCAC) to conduct an amphibious assault

 

from beyond the horizon.

 

 

 

II.  Problem:  Amphibious assault techniques must be devel-

 

oped to exploit the capabilities of the LCAC, reduce the

 

vulnerability of the amphibious task force to shore-based

 

weapons systems, and enable the landing force to achieve

 

tactical surprise and avoid enemy coastal defenses.

 

 

 

III. Data:  The traditional amphibious assault, charac-

 

terized by ships stationed close to the coastline

 

discharging slow-moving landing craft and assault amphibian

 

vehicles (AAVs) toward easily predictable beaches, offers

 

little hope of achieving tactical surprise, and is

 

vulnerable to modern defensive weapons.  The LCAC can

 

transport heavy equipment, including tanks and AAVs, at

 

speeds up to fifty knots directly to inland landing sites.

 

It is capable of negotiating about seventy-three percent of

 

the world's coastlines as compared to about seventeen

 

percent for displacement-type craft.  The LCAC can be

 

carried by all well-deck ships.  However, until current

 

shipbuilding programs are completed, some shortfalls will

 

exist in the number of LCACs that can be embarked to support

 

amphibious landings.  Employment of the LCAC with existing

 

and programmed ships, craft, and vehicles to launch an

 

assault from an amphibious task force stationed beyond the

 

horizon will present a number of challenges.  Naval gunfire

 

ships will be largely out of range to support the initial

 

assault.  The build-up of combat power ashore will be slow

 

because the turn-around time for LCACs launched from beyond

 

the horizon is lengthy.  Tank landing ships (LSTs) and

 

displacement-type landing craft organic to LKAs and MPS

 

ships must be integrated into the landing plan without

 

compromising the advantage gained by a high-speed surprise

 

LCAC assault.  Finally, the question of what to do with the

 

AAVs must be addressed.  Assault infantry units landed by

 

LCACs without AAVs will have limited mobility ashore and no

 

armored protection.  If LCACs are used to land AAVs with the

 

assault infantry units, the availability of LCACs to land

 

TOWs, tanks, and artillery in scheduled and on-call waves

 

will be significantly reduced.

 

 

 

IV.  Conclusions:  Until the assault elements of the landing

 

force are established ashore, the amphibious task force must

 

remain beyond the horizon, not only for its own protection,

 

but to deceive the enemy as to the location of the attack.

 

The capability of the LCAC to cross heretofore unassailable

 

beaches at high speed must be exploited to avoid enemy

 

defenses and gain surprise.  Assault infantry units must

 

have the necessary mobility ashore to seize deep objectives,

 

link-up with helicopterborne forces, and exploit the

 

advantage gained by a surprise landing.  The momentum of the

 

attack must be maintained by accelerating the offloading of

 

ships, to include using displacement-type craft, to hasten

 

the build-up of combat power ashore.

 

 

 

V.  Recommendations:  Future amphibious assaults should be

 

launched from twenty to twenty-five miles offshore.  Es-

 

corted by attack helicopters, LCACs should carry scheduled

 

and on-call waves of infantry mounted in AAVs, TOWs, tanks,

 

and artillery to inland landing sites.  Once the leading

 

elements of the landing force are established ashore, the

 

amphibious task force should move closer to the coastline to

 

accelerate offloading by reducing LCAC turn-around time, and

 

open conventional beaches to accommodate displacement-type

 

landing craft.

 

                  LCAC AND THE OVER-THE-HORIZON

                       AMPHIBIOUS ASSAULT

 

                           OUTLINE

 

Thesis Statement:  Future amphibious assaults will be

 

conducted by using LCACs launched from ships stationed well

 

beyond the horizon to carry scheduled and on-call waves of

 

infantry mounted in AAVs, TOWs, tanks, and artillery to

 

inland landing sites, whereupon the amphibious task force

 

will move closer to the coastline to accelerate offloading

 

by LCACs and, if necessary, open conventional beaches for

 

displacement-type landing craft.

 

 

 

I.   The requirement for an over-the-horizon amphibious

 

     assault capability

 

 

 

II.  The Landing Craft Air Cushion (LCAC)

 

     A.  Introduction into the fleet

 

     B.  Operational characteristics

 

     C.  Payloads

 

     D.  Compatibility with ships

 

     E.  Limitations and vulnerabilities

 

III. The problems associated with an over-the-horizon

 

     amphibious assault

 

     A.  Amphibious ready group configuration

 

     B.  Naval gunfire support

 

     C.  Ship-to-shore movement distance and time

 

     D.  Integration of LCACs, displacement-type landing

 

         craft, and AAVs

 

          1.  Displacement-type landing craft

 

          2.  AAVs

 

 

 

IV.  The concept for conducting an over-the-horizon

 

     amphibious assault

 

     A.  Composition of scheduled and on-call waves

 

          1.  AAVs in LCACs

 

          2.  TOWs, tanks, and artillery in LCACs

 

     B.  Control of ship-to-shore movement

 

          1.  Approach and retirement routes

 

          2.  Landing sites

 

     C.  Movement inshore of amphibious task force

 

     D.  Opening of conventional beach

 

     E.  Concept of fire support

 

                LCAC AND THE OVER-THE-HORIZON

 

                     AMPHIBIOUS ASSAULT

 

     It is hard to envision, in 1985, an amphibious assault

 

against a defended beach.  Sufficient naval gunfire ships to

 

obliterate fortifications and pound enemy defenders sense-

 

less no longer exist.  Lumbering amphibious ships standing

 

three to five miles offshore are easy prey to modern,

 

precision-guided, shore-based weapons.  Landing craft and

 

amphibious assault vehicles, remarkably similar to their

 

1942 predecessors, churning toward an easily predictable

 

beach at eight miles per hour are themselves vulnerable to

 

shore-based fires, and offer little hope of attaining

 

tactical surprise.  To be sure, the helicopter permits the

 

rapid and unexpected landing of light infantry.  However,

 

existing means for landing heavy combat support and combat

 

service support elements essential for the build-up of

 

credible combat power ashore have improved little since the

 

1940's, and arc restricted by reefs, tides, beach gradient

 

and beach trafficability.  Any surprise achieved by heli-

 

copterborne assault is soon compromised by a ponderous

 

surface assault.

 

     Because of the vulnerability of all types of ships,

 

craft, and amphibious vehicles to modern weapons systems,

 

the modern amphibious assault must be launched from beyond

 

the range of shore-based target acquisition systems.

 

Tactical surprise must be achieved to permit the rapid

 

landing of heavy combat and combat support elements across

 

undefended beaches before the enemy can react to the as-

 

sault.  Until these parameters are met, many will doubt the

 

continued practicality of the amphibious assault.

 

     The introduction of the Landing Craft Air Cushion

 

(LCAC) will make possible surprise landings across unde-

 

fended beaches, and will prove to be the most revolutionary

 

development in amphibious warfare since the advent of the

 

helicopter.  In conjunction with helicopterborne assaults,

 

LCACs launched from twenty to twenty-five miles offshore

 

will cross undefended segments of coastline at high speed

 

and land infantry mounted in assault amphibian vehicles

 

(AAVs), TOWs, tanks, and artillery at sites up to one mile

 

inland.  The ability of an LCAC-equipped amphibious task

 

force to paralyze enemy defenders  by striking unexpectedly

 

with speed and power promises to rejuvenate the utility and

 

effectiveness of the amphibious assault.

 

     The first production LCACs have already been delivered

 

to the fleet. By the summer of 1986, six LCACs will be

 

operational with Assault Craft Unit Five at Camp Pendleton,

 

California.  During Fiscal Year 1987, Assault Craft Unit

 

Four, based at Little Creek, Virginia, will begin receiving

 

the LCAC.  By 1992, a total of ninety LCACs will have been

 

delivered.  Assault Craft Unit Five and Assault Craft Unit

 

Four will each be assigned forty-five LCACs.1   Ultimately,

 

most conventional landing craft will be replaced with

 

LCACs.2

 

     The LCAC employs hovercraft technology to skim across

 

the ocean surface on a cushion of air.  It has a range of

 

two hundred nautical miles.3  With a full payload, it will

 

exceed speeds of fifty knots in sea state two, and forty

 

knots in sea state three.  Overloaded, it will still achieve

                                      

thirty knots in sea state two.4   Unconstrained by winds,

 

tides, reefs, underwater obstacles, mines, beach gradient

 

and beach trafficability,5 the LCAC can cross the shoreline

 

and proceed inland at speeds up to thirty-five knots.6

 

Ashore, it will cross twenty-foot ditches7 and five-foot

                                          

vertical obstacles,8  knock down small trees,9  and climb

 

gradients up to thirteen percent.10

 

     The most significant operational characteristics of the

 

LCAC are its ability to cross beaches that heretofore have

 

been unassailable, and its speed.  The LCAC will cross

 

approximately seventy-three percent of the world's coast-

 

lines, as compared to about seventeen percent for conven-

 

tional craft,11 enormously complicating a defender's task.

 

Conventional landing craft and vehicles travel at speeds of

 

eight to eleven knots, and must be launched from three to

 

five miles offshore.  The fifty-knot speed of the LCAC

 

permits the amphibious task force to remain over the hori-

 

zon, beyond the reach of shore-based target acquisition

 

systems.  The vulnerability of the amphibious task force is

 

reduced, and the specific location of the landing is not

 

disclosed by the presence of ships close offshore.

 

     The capabilities of the LCAC facilitate tactical

 

deception to achieve surprise and project forces across an

 

undefended beach.  To illustrate, an LCAC-equipped amphi-

 

bious force approaching Norfolk, Virginia, at dusk, can

 

launch a dawn assault anywhere between Long Island, New

 

York, and Myrtle Beach, South Carolina!12  Put another way,

 

with a ship-to-shore transit time of under fifty minutes, an

 

amphibious task force twenty miles offshore can project

 

forces ashore anywhere across a forty-mile front!

 

     The LCAC carries a standard sixty-ton payload or an

 

overload seventy-five ton payload on a sixty-six foot by

 

twenty-six foot four inch rectangular cargo deck.  It is

 

equipped with bow and stern ramps that will permit drive-

 

through loading and off-loading of any vehicle organic to

 

the landing force.13  Typical LCAC loads are shown in Figure

 

1.

 

 

                        TYPICAL LCAC LOADS

 

4600        Cubic feet cargo

250        Combat-equipped Marines

3        Assualt amphibian vehicles (AAVs)

4        Light Armored Vehicles (LAVs)

1        Tank and 1 LAV

2        M198 howitzers with prime movers

12        High mobility multipurpose wheeled

Vehicles (HMMWV)

 

               

                             Figure 1*

 

     The LCAC is designed to operate from the well decks of

 

amphibious ships.  On its air cushion it measures eighty-six

 

feet nine inches in length, forty-seven feet in width, and

 

twenty-three feet six inches in height.15  It can enter or

 

depart the flooded or dry well deck of all existing well-

 

deck ships while the ship is underway or at anchor.16  Newer

 

classes of amphibious ships, such as the LSD-41 and the LHD,

 

are being designed specifically to accommodate the LCAC.

 

Ships capable of carrying LCACs are shown in Figure 2.

 

LSD-class ships will normally carry one LCAC less than

 

capacity to provide room for shipboard maintenance.17

 

Because of the height of the LCAC, LSDs with mezzanine decks

 

installed will be further limited in the number of LCACs

 

they can carry.

 

*Footnote 14.

 

 

            SHIPS CAPABLE OF CARRYING LCACs

 

        LHD                         3 LCACs

        LHA                         1 LCAC

        LSD-28 class                3 LCACs

        LSD-36 class                4 LCACs

        LSD-41 class                5 LCACs

        LPD                         2 LCACs

 

                  Figure 2*

 

 

     If current shipbuilding programs are continued, the

 

amphibious force will be able to lift all ninety programmed

 

LCACs by the mid-1990's.19  Until then, shortfalls will

 

occur.  Studies have shown that sixty-nine to eighty-three

 

LCACs will be required to support a Marine Amphibious Force                                               

 

(MAF) amphibious assault.20  The amphibious force of 1986

 

will be capable of lifting just sixty-four LCACs.21

 

Thirty-five to forty-two LCACs will be required to support a

 

Marine Amphibious Brigade (MAB).22  A representative mix of

 

ships available to embark a MAB might include three LHAs,

 

seven LPDs, one LSD-41 class ship, three LSD-36

 

class ships, and one LSD-28 class ship, with a total capa-

 

city to lift only thirty-three LCACs.  Six to nine LCACs

 

will be required to support a Marine Amphibious Unit

 

(MAU).23  Typical amphibious ready groups (ARGs) used to

 

deploy MAUs are configured with one LHA, one LKA, and one

 

*Footnote 18

 

LST, with a total capacity of one LCAC; or one LHA, one LPD,

 

and one LST, with a total capacity of three LCACs; or one

 

LPH, one LPD, one LSD, and two LSTs, with a total capacity

 

of five or six LCACs, depending on the class of LSD.

 

     Like any other vehicle, the LCAC has limitations and

 

vulnerabilities that must be recognized prior to considering

 

its employment. It is a big, noisy craft that displays a

                                                  

characteristic "rooster tail" of sea spray or dust.24

 

Although tests have shown that it can sustain considerable

                                     

damage and continue to operate,25  it is nonetheless an

 

unarmored craft.26  Essentially a flatland vehicle, its

 

speed and maneuverability ashore is constrained.  It is

 

particularly difficult to maneuver in reverse.27  Finally,

                                                      

the LCAC weighs eighty-seven and one-half tons, empty.28  If

 

disabled ashore, it will be extremely difficult to extract.

 

In fact, no landing force vehicle is capable of towing it.29

 

     Employment of the LCAC with existing and programmed

 

amphibious ships, craft, and vehicles to conduct an amphib-

 

ious assault from beyond the horizon will present a number

 

of challenges.  Configuration of amphibious ready groups

 

(ARGs), naval gunfire support, time-distance factors

 

affecting the ship-to-shore movement, and the integration of

 

LCACs and displacement-type craft are issues which must be

 

addressed.

 

     As shown above, amphibious ships likely to be available

 

in the near term to embark the assault echelons of a MAF or

 

MAB have the capacity to carry a significant number of

 

LCACs, although slightly fewer than desired.  Configuration

 

of ARGs used to forward-deploy MAUs will have to be

 

specifically tailored with the capacity to carry the minimum

 

six LCACs determined to be adequate to support a MAU land-

 

ing.  Of the three ARG configurations in use today (LHA,

 

LKA, LST; LHA, LPD, LST; and LPH, LPD, LSD, LST, LST), only

 

the LPH, LPD, LSD, LST, LST configuration will carry six

 

LCACs, and then only if the LSD is an LSD-41 class.

 

Introduction of the LHD, capable of carrying three LCACs, to

 

replace the LPH will significantly improve the situation, as

 

will the continued production of the LSD-41 class.  However,

 

programmed LCAC deliveries will be completed long before the

 

last LPH or LSD-36 class ship is retired.  In the interim,

 

LCAC-equipped ARGs will have to be configured with an LPH,

 

LPD, and an LSD-41 class ship, or with an LHA, LPD, and an

 

LSD-36 or LSD-41 class ship.

 

     The traditional concept of using naval gunfire for 

 

preparatory fires and to support the amphibious assault                                      

 

until landing force artillery is ashore will not work for an

                                         

assault launched from twenty to twenty-five miles offshore.

 

Ships armed wish 5"/54 caliber guns will not be able to

 

reach targets without moving to within visual range of the

 

coastline, and by doing so will compromise the surprise

 

achieved by retaining the amphibious task force beyond the

 

horizon.  Even the battleship, with its sixteen-inch guns

 

effective to twenty-four miles, will have limited utility if

 

stationed beyond the horizon.  The LCAC-borne amphibious

 

assault launched from beyond the horizon will have to be

                

supported by alternative means, because naval gunfire ships

               

will be largely out of range.

 

     Once launched, it is essential that the momentum of an

 

amphibious assault be maintained by the rapid and continuing

                                                                         

build-up of combat power ashore.  Sufficient landing craft

                  

will never be available to land all desired combat, combat

 

support, and combat service support elements in one lift.

            

Each craft must make many trips to the beach.  This will

 

remain true with the LCAC.  Additional consideration,

 

however, must be given to the distance the LCAC must transit

 

in the ship-to-shore movement, and the relatively limited

 

endurance of the craft as applies to maintaining the momen-

 

tum of the assault.

 

     Launched from twenty miles offshore, LCAC transit time

 

to the beach will be about thirty minutes.  Ten minutes will

 

be required to offload in the landing site.  Thirty minutes

 

transit time back to the ship, twenty minutes to enter the

 

well deck, load, and depart the well deck, and thirty more

 

minutes transit time back to the beach, all works out to an

 

hour and a half between the time an LCAC makes its initial

 

landing and returns with a second load!  Turn-around time

 

for a third trip to the beach will be further increased

 

because the LCAC must be refuelled after every second trip

 

ashore!30

 

     Undoubtedly the biggest dilemma facing the amphibious

 

planner is the integration of fifty-knot LCACs with nine-knot

 

displacement-type landing craft and eight-knot AAVs into the

 

ship-to-shore movement plan. The LCAC is designed to

                               

replace the venerable Landing Craft, Utility (LCU), and

 

Landing Craft, Mechanized (LCM-8).  However, LKAs carry

 

organic LCM-8s, and MPS ships will carry organic LCM-8s, and

 

causeways.31 The LST is designed to beach itself, or

 

offload by causeway.  These type ships will remain in the

 

fleet long after the introduction of the LCAC and will

 

almost assuredly be found in any amphibious task force.

 

Ship-to-shore movement plans must be designed to capitalize

 

on the speed and range of the LCAC, yet still provide for

 

the landing of considerable quantities of supplies and

 

equipment by displacement-type craft across conventional

 

beaches.

 

     The assault amphibian vehicle (AAV) is designed to

 

provide armored protection to the assault elements of the

 

landing force during the ship-to-shore movement.  It pro-

 

vides mobility ashore, which is particularly critical during

 

the initial stages of an assault when surface-landed ele-

 

ments seek to achieve a rapid link-up with helicopterborne

 

forces.  The problem is, it only travels eight miles per

 

hour in the water, and the follow-on to the current AAV is

                                                        

not expected to have a significantly greater water speed.32

 

It is impractical to launch AAVs from twenty miles offshore.

 

On the other hand, bringing ships to within fice miles of

 

the coast to launch AAVs compromises the advantage of an

 

LCAC-equipped force to launch an assault from beyond the

 

horizon.  Hence the dilemma:  What to do with the AAVs?

 

Based on the premise that the assault will be launched from

 

beyond the horizon, two solutions are apparent, each with

 

advantages and disadvantages.

 

     First, assault infantry units can be landed without

 

AAVs.  Each LCAC can carry up to 250 Marines, providing the

 

potential for an incredible swift build-up of infantry

                                      

strength ashore, while retaining the preponderance of the

 

LCAC force to transport pre-loaded TOWs, tanks and artillery

 

ashore in on-call waves.  This concept also provides an

 

opportunity to alter the doctrinal precept of landing

 

two-thirds of the assault force by helicopter and one-third

 

by surface assault.

 

     Landing assault infantry elements without AAVs has

 

disadvantages.  Once ashore, the infantry will have only

 

limited mobility and no armored protection. More impor-

 

tantly, the loss of a single LCAC carrying 250 Marines in

 

the initial assault would be a significant loss to almost

 

any size force, and might very well jeopardize the mission.

 

     The other alternative is to mount the assault infantry

                  

units in AAVs and carry the AAVs ashore in LCACs.  Each LCAC

 

can carry three AAVs.  Infantry strength is not concentrated

 

on a few LCACs, lessening the impact of losing an LCAC.

 

Once ashore, the infantry is provided with mobility and

 

armored protection.

 

     Carrying the AAVs ashcre in LCACs constrains the

 

landing force commander to a surface assault by the doc-

 

trinal one-third of his assault force, and significantly

 

reduces the number of LCACs available to carry TOWs, tanks,

 

artillery, and other combat support and combat service

 

support units ashore in scheduled or on-call waves.  For

 

example, five of six LCACs supporting a MAU would be

 

required to land the fourteen AAVs normally assigned.

 

Sixteen of thirty-three LCACs supporting a MAB would be

 

required to land forty-seven assigned AAVs.  If all ninety

 

programmed LCACs were embarked to support a single MAF,

 

sixty-nine would be required just to land 208 assigned AAVs!

 

Needless to say, it is unlikely that LCACs would be

 

available for floating dumps or free boats, and alternate

 

techniques for emergency resupply and landing command groups

 

must be developed.  By landing the AAVs with the assault

 

infantry units, the infantry is provided with mobility and

 

armored protection, but is left with little combat support.

 

Remembering that an hour and a half will elapse before the

 

first LCAC will return to the beach with its second load, a

 

significant delay in the build-up of tank and artillery

 

strength ashore could occur.

 

     The characteristics, capabilities, and limitations of

 

the LCAC, and some of the problems associated with an

 

amphibious assault launched from beyond the horizon have

 

been discussed.  How, then, will an over-the-horizon amphib-

 

ious assault be conducted?  Capitalizing on deception and

 

speed to achieve tactical surprise, LCACs launched from

 

twenty to twenty-five miles offshore will carry scheduled

 

and on-call waves of infantry mounted in AAVs, TOWs, tanks,

                                                                        

and artillery to landing sites up to one mile inland.  Once

 

the assault elements are established ashore, the amphibious

 

task force will move closer to the beach to reduce LCAC

 

transit time and accelerate the build-up of combat power

 

ashore.  If required, a conventional beach can subsequently

 

be opened to accommodate LSTs and other displacement-type

 

landing craft.

 

     Except in unusual circumstances, it will be necessary

 

for the LCACs to transport AAVs ashore with the assault

 

infantry units.  The surface assault will be limited to just

                                                                       

one-third of the landing force assault elements, and the

 

number of LCACs available to pre-load and land TOWs, tanks,

 

and artillery in scheduled and on-call waves will be

 

dramatically reduced.  Nonetheless, it is essential that the

 

infantry have the mobility to quickly seize inland objec-

 

tives, link-up with helicopterborne forces, and exploit the

 

surprise gained by a high-speed assault launched from beyond

 

the horizon.

 

     Expecting a delay of an hour and a half until the first

 

LCAC returns to the beach with a second load, the early

 

landing of combat support units is mandatory.  All available

 

LCACs not used to transport AAVs will be used to land TOWs,

 

tanks, and artillery in scheduled or on-call waves.  There

 

will be no requirement for LCACs to carry heavy beachmaster

 

or landing support equipment ashore in on-call waves.  The

 

capability of the LCAC to move heavy equipment across the

 

beach to inland landing sites virtually eliminates any need

 

for the early introduction of landing support units.

 

     The requirement to use every available LCAC to get the

 

assault elements ashore with as much combat support as

 

possible in the first lift leaves no suitable craft for

 

floating dumps or free boats.  Floating dumps and free boats

 

will become a thing of the past.  Emergency supplies for

 

units landed by LCACs will be prepositioned on ships and

 

brought ashore by helicopter.  Command groups will have to

 

land in scheduled or on-call waves, or use helicopters to go

 

ashore when desired and link-up with command vehicles landed

 

with early waves.

 

     A primary control ship will be designated to control

 

the movement of LCACs from the ships to inland landing

 

sites.  Loaded LCACs will  be formed into waves. The LCAC

 

waves will follow designated routes, very similar to heli-

 

copter approach and retirement lanes, to and from inland

 

landing sites.  Alternate routes and alternate landing sites

 

will be designated.  Designated rendezvous points, departure

 

points, penetration control points, control points, and

 

initial points will be used to control the movement of LCAC

 

waves to arid from landing sites.

 

     Primary and alternate LCAC landing sites will be

 

selected to facilitate the seizure of initial landing force

 

objectives, but will not normally be located more than one

 

mile inland.  The limited overland speed and maneuverability

 

of the LCAC, and its size, noise, and "roostertail" signa-

 

ture make it a vulnerable target for enemy gunners ashore.

 

If the LCAC must travel several miles inland to reach a

 

landing site, ship-to-shore transit time will be increased,

 

and it will take a longer time for each LCAC to return to

 

the landing site with a second load.  The importance of

 

reducing the LCAC turn-around time to maintain a rapid and

 

continuous build-up of combat power ashore will dictate that

                                

landing sites be located not more than about one mile

 

inland.

 

 

     Special consideration must be given to the size and

 

trafficability of potential landing sites.  Landing sites

 

should be big enough to permit LCACs to easily maneuver in

 

and out, preferably without having to reverse direction,

 

Ideally, each site should accommodate three or more LCACs,

 

so that one or two disabled craft won't obstruct the whole

 

site.  Landing sites should provide good trafficability for

 

tracked and wheeled vehicles to permit rapid offloading and

 

reduce landing support requirements.

 

     After scheduled and on-call waves have landed and

 

initial objectives have been seized, it will no longer be

 

necessary to conceal the presence of the amphibious task

 

force.  Emphasis must be placed on rapidly landing addi-

 

tional combat, combat support, and combat service support

 

units necessary to sustain the momentum of the attack.  To

 

speed offloading and hasten the build-up of combat power

 

ashore by reducing the LCAC ship-to-shore transit time, the

 

amphibious task force will close to within three to five

 

miles of the coast.  Minesweeping operations, initiated

 

after scheduled and on-call waves have been landed by LCACs,

 

will clear lanes for ships to move closer to the coast.

 

     If the amphibious task force includes LSTs or LKAs and

 

MPS ships with organic displacement-type landing craft, a

 

conventional beach will be opened.  These type ships will

 

approach the coast preceded by the ships being offloaded by

 

LCACs and the minesweeping operations.  Underwater and beach

 

obstacle clearance operations to support the landing of

 

displacement-type craft will be initiated after scheduled

 

and on-call waves have been landed by LCACs.

 

     An amphibious assault launched from beyond the horizon

 

will present unique fire support problems.  Because naval

 

gunfire ships will be out of range to support the initial

 

landings, the necessity of achieving tactical surprise is

 

doubly important.  The initial assault will be supported by

 

ship-launched surface-to-surface missiles and air strikes.

 

Attack helicopters will escort the LCACs across the beach

 

and into landing sites, and will provide close-in fire

 

supression and anti-tank fires in support of assault infan-

 

try elements.

 

     The inability of naval gunfire ships to support the

 

initial assault will make the early landing of TOWs, tanks,

 

and artillery highly desireable.  If the early landing of

 

TOWs, tanks, and artillery is restricted by limited LCAC

 

assets and a lengthy ship-to-shore turn-around time, even

 

greater reliance will be placed on close air and attack

 

helicopter support.  Once scheduled and on-call waves have

 

been landed by LCACs, naval gunfire ships will move inshore

 

to fire-support stations within range of landing force

 

objectives ashore.

 

     The vulnerability of ships and slow-moving landing

 

craft to modern weapons systems has made the traditional

 

concept of amphibious assault almost obsolete.  The

 

incorporation of LCACs into the amphibious forces will

 

permit the resurgence of the amphibious assault as a daring

 

but highly practical form of offensive warfare.  The

 

capability of the LCAC to be launched from well beyond the

 

horizon and carry assault forces across the coastline at

 

high speed will again place the amphibious attacker in a

 

position of advantage.  Avoiding enemy defenses, and seeking

 

to achieve tactical surprise, future amphibious assaults

 

will be launched from twenty to twenty-five miles offshore.

 

Scheduled and on-call waves of infantry mounted in AAVs,

 

TOWs, tanks, and artillery will be carried to inland landing

 

sites by LCACs escorted by attack helicopters.  Once the

 

leading elements of the landing force have been established

 

ashore, the amphibious task force can safely move inshore to

 

speed offloading and maintain the momentum of the attack.

 

     The introduction of the LCAC promises to be the most

 

significant development in the art of amphibious warfare

 

since the advent of the helicopter.  Innovative and imagina-

 

tive employment of the LCAC will permit swift, powerful, and

 

unexpected amphibious strikes across beaches heretofore

 

unassailable.  In the years ahead, the stock-in-trade of the

 

Navy-Marine Corps team will be the high-speed, over-

 

the-horizon amphibious assault.

 

 

 

                         FOOTNOTES

 

     1Marine Corps Association, "LCAC Rollout," Marine Corps

Gazette, 68 (June 1984), p. 10.

 

     2Dov S. Zakheim, "The Role of Amphibious Operations in

National Military Strategy," Marine Corps Gazette, 68 (March

1984), p. 38.

 

     3Roy McLeavy, ed., Jane's Surface Skimmers,  Hovercraft

and Hydrofoils 1983, 16th ed. (London:  Jane's Publishing

Company, Limited, 1983), p. 126.

 

     4Roy McLeavy, "LCAC:  Amphibious Assault at 50 Knots,"

Jane's Defense Review, 4 (August 1983), p. 755.

 

     5Ibid, p. 751.

 

     6Vincent C. Thomas Jr., "A Much-Needed Lift,"  Sea

Power, 25 (November 1982), p. 30.

 

     7Col R. B. Rothwell, USMC, "Toward a New Amphibious

Tactical Concept," Marine Corps Gazette, 67 (July 1983), p.

66.

 

     8Thomas L. Clancy Jr., "The Floating Shell Game," U. S.

Naval Institute Proceedings, 108 (July 1982), p. 116.

    

     9Rothwell, p. 66.

 

     10Clancy, p. 116.

 

     11Roy McLeavy, "LCAC, Amphibious Assault at 50 Knots,"

Jane's Defense Review, 4 (August 1983), p. 751.

 

     12Col John G. Miller USMC, "LCAC and the Lift Dilemma:

Sandbags...Rice Bowls...and Pandora's Box," Marine Corps

Gazette, 65 (December 1981), p. 49.

 

     13Roy McLeavy, ed., Jane's Surface Skimmers.

Hovercraft and Hydrofoils 1983, 16th ed. (London:  Jane's

Publishing Company, Limited, 1983), p. 126.

 

     14Presearch Incorporated, Technical Memorandum No.

82-007.  Employment of Landing Craft Air Cushion (LCAC) in

Contingency Amphibious Operations (Arlington, VA: Presearch

Incorporated, 1982), p. 11.

 

    

     15Roy McLeavy, ed. Jane's Surface Skimmers.  Hovercraft

and Hydrofoils 1983, 16th ed. (London: Jane's Publishing

Company, Limited, 1983), p. 126.

 

     16Alan Blunden, "Military Hovercraft," International

Defense Review, 15 (November 1982), p. 1544.

 

     17Presearch Incorporated, Technical Memorandum No.

82-007.  Employment of Landing Craft Air Cushion (LCAC) in

Contingency Amphibious Operations (Arlington, VA:  Presearch

Incorporated, 1982), p. 30.

 

     18Rothwell, p. 65.

 

     19Rothwell, p. 65.

 

     20Presearch Incorporated, Technical Memorandum No.

82-007.  Employment of Landing Craft Air Cushion (LCAC) in

Contingency Amphibious Operations (Arlington, VA:  Presearch

Incorporated, 1982), p. 1.

 

     21Roy McLeavy, "LCAC:  Amphibious Assault at 50 Knots,"

Jane's Defense Review, 4 (August 1983), p. 129.

 

     22Presearch Incorporated, Technical Memorandum No.

82-007.  Employment of Landing Craft Air Cushion (LCAC) in

Contingency Amphibious Operations (Arlington, VA:  Presearch

Incorporated, 1982), p. 1.

 

     23Ibid., p. 1.

 

     24Col Joseph H. Alexander USMC, "Amphibious Warfare:

What Sort of Future?"  U. S. Naval Institute Proceedings,

108 (February 1982), p. 66.

 

     25Rothwell, p. 65.

 

     26Alexander, p. 65.

 

     27Rothwell, p. 66.

 

     28Roy McLeavy, ed., Jane's Surface Skimmers.

Hovercraft and Hydrofoils 1983, 16th ed. (London:  Jane's

Publishing Company, Limited, 1983), p. 126.

 

     29Rothwell, p. 66.

 

     30Presearch Incorporated, Technical Memorandum No.

82-007.  Employment of Landing Craft Air Cushion (LCAC) in

Contingency Amphibious Operations (Arlington, VA:  Presearch

Incorporated, 1982), p. 16.

 

     31LtCol John S. Lowery USMC, "MPS Concept Becomes a

Reality," Marines, 13 (December 1984), p. 15.

 

     32Alexander, p. 64.

 

                        BIBLIOGRAPHY

 

Alexander, Joseph H.  Col, USMC.  "Amphibious Warfare:  What

     Sort of Future?"  U. S. Naval Institute Proceedings,

     108 (February 1982), 62-68.

 

Barrow, Robert H., Gen, USMC.  "CMC FY 82 Posture

     Statement."  Marine Corps Gazette, 65 (April 1981),

     28-39.

 

Barrow, Robert H., Gen, USMC.  "Congress and the Corps.  CMC

     FY 84 Posture Statement."  Marine Corps Gazette, 67

     (April 1983), 38-49.

 

Blunden, Alan. "Military Hovercraft."  International Defense

     Review, 15 (November 1982), 1539-1545.

 

Clancy, Thomas L. Jr. "The Floating Shell Game." U. S. Naval

     Institute Proceedings, 108 (July 1982), 115-118.

 

Grace, J. J., Col, USMC (Ret).  "Land the Landing Force

     Where it Will do the Most Good:  A New Look at an Old

     Mission."  U. S. Naval Institute Proceedings, 107 (May

     1981), 114-131.

 

Hamilton, C. F., Maj, USMC.  "LAV and the Amphibious

     Assault."  Marine Corps Gazette, 67 (October 1983),

     66-73.

 

Kelly, Paul X., Gen, USMC.  "Congress and the Corps.  CMC FY

     85 Posture Statement to Congress." Marine Corps Ga-

     zette, 68 (April 1984), 31-49.

 

Lowery, John S., LtCol, USMC.  "MPS Concept Becomes a

     Reality."  Marines, 13 (December 1984), 12-23.

 

Marine Corps Association.  "Progress Being Made With

     LCACs."  Marine Corps Gazette, 65 (October 1981), 4.

 

Marine Corps Association.  "LCAC Rollout."  Marine Corps

     Gazette, 68 (June 1984), 10.

 

Marine Corps Association.  "LSD-42 Launched at Shipyard

     Ceremony."   Marine Corps Gazette, 68 (September 1984),

     4.

 

Marine Corps Association.  "Testing is Completed on LCAC."

     Marine Corps Gazette, 69 (February 1985), 6.

 

McLeavy, Roy, ed.  Jane's Surface Skimmers.  Hovercraft and

     Hydrofoils 1983.  16th ed. London:  Jane's Publishing

     Company, Limited, 1983.

 

McLeavy, Roy.  "LCAC:  Amphibious Assault at 50 Knots."

     Jane's Defense Review, 4 (August 1983), 751-755.

 

Miller, John G., Col, USMC.  "LCAC and the Lift Dilemma:

     Sandbags...Rice Bowls...and Pandora's Box."  Marine

     Corps Gazette, 65 (December 1981), 47-50.

 

Presearch Incorporated.  Technical Memorandum No. 82-007.

     Employment of Landing Craft Air Cushion (LCAC) in

     Contingency Amphibious Operations.  Arlington, VA:

     Presearch Incorporated, 1982.

 

Presearch Incorporated.  Technical Report No. 566.

     Preliminary Comparison of Three Alternative Landing

     Concepts.  Arlington, VA:  Presearch incorporated,

     1982.

 

Rothwell, R. B., Col, USMC.  "Toward a New Amphibious

     Tactical Concept."  Marine Corps Gazette, 67 (July

     1983), 63-67.

 

Thomas, Vincent C. Jr. "A Much Needed Lift."  Sea Power, 25

     (November 1982), 22-32.

 

U. S. Marine Corps.  NAVMC 2710.  Marine Air-Ground Task

     Forces.  Washington, 1983.

 

U. S. Marine Corps.  Marine Corps Development and Education

     Command.  Amphibious Ships, Landing Craft, and Vehi-

     cles, IP 3-4.  Quantico, 1982.

 

U. S. Marine Corps.  Education Center, Marine Corps

     Development and Education Command.  Naval Gunfire and

     Supporting Arms Planning Reference Handbook 1984-1985.

     Quantico, 1984.

 

Zakheim, Dov S.  "The Role of Amphibious Operations in

     National Military Strategy."  Marine Corps Gazette, 68

     (March 1984), 35-39.