© 2004 Robert H. Stoner - used by permission

Naval Special Warfare: Small Combatant Craft Development – World War 2 through Vietnam


GMCM (SW) Robert H. Stoner (Ret)


In order to understand how the UDT/SEAL/MST units evolved during the Vietnam War, we have to understand how things were done in the beginning.


Boat Support Unit ONE got into the Naval Special Warfare role through its operation of fast patrol boats (PTF) beginning in late 1963.  As the small craft types multiplied for the prosecution of the war, BSU-1 became heavily involved in the training of crews to man the boats.  Meanwhile, across the road separating the Coronado, CA Amphibious Base and the UDT/SEAL compound other things were happening.


Underwater Demolition Teams had evolved from the Navy Combat Demolition Units of World War 2.  As constituted, the UDT had small boats for accomplishing their mission.  The smallest of these was the IBS (or small inflatable boat).  The IBS was an 8 to 10-man raft that could be fitted with a small outboard engine.  The IBS was employed for short-range operations.


No photo found


Originally called the Landing Craft Rubber (Large), this inflatable rubber boat became known by the more common term – IBS for Inflatable Boat, Small.  As shown, the IBS had a pointed bow that, over time, became more blunt.  Over the decades the IBS was in use, its overall length of 16 feet, 8-foot beam, nil draft, and 396 pound weight (or 474 pounds with a 9-1/2 HP outboard) remained fairly constant.  Speed was roughly 4.5 knots with the outboard and 55 yards per minute with eight experienced men paddling.  The IBS was the workhorse of NCDU/UDT/SEAL units until it was replaced by the Zodiac series of inflatable boats.


The next step up was the landing craft personnel (LCP), landing craft personnel, ramped [LCP(R)], or Landing Craft Personnel, Large (LCPL).  Higgins in New Orleans, LA, had designed the original boats during World War 2 for amphibious use.  All the boats were 36 feet long, wood or steel construction, and powered by 6-cylinder diesel engines.  The LCP had a blunt, tapered bow for running up on beaches.  The single propeller and rudder were protected by a skeg attached to the keel.  Immediately in back of the bow were two, three-foot diameter holes in the deck that mounted .30 machineguns.  In back of the gun positions on the centerline was a conning station [relocated to the left hand front corner of the well deck for the LCP(R)].  The well deck carried the troops.  The engine was located under a cover in the center of the well deck and the fuel tanks were located aft.  Troops exiting the LCP had to jump over the side and wade to the beach.  The boat was made primarily of wood with a Ľ-inch thick “armor” plate attached to the sides of the craft.

Drawing of the LCP (aka “Higgins” boat) as used at the start of World War 2.  Lack of a bow ramp meant troops had to exit by jumping over the side.  The boat was soon replaced by the LCP(R) and these boats were used by the first NCDU/UDT units.


The LCP(R) was a modified version of the LCP.  The bow got blunter and became a ramp.  There was a connecting passage between the well deck compartment and the ramp that allowed troops to exit from the bow of the boat.  The twin machine gun positions were located similarly to those on the LCP.  There was an inner safety door that separated the bow ramp from the interior well deck to prevent unintended flooding of the boat.  The boat was also made of wood with a Ľ-inch thick “armor” plate attached to the sides of the craft.




A World War 2 photo of the LCP(R) with a full troop load. (Photo: US Navy)


Both LCP and LCP(R) were used to drop off and pickup swimmers.  To do this, the LCP or LCP(R)  [and later LCPL] moved parallel to the beach with and IBS lashed along side.  Swimmers would go over the side of the LCP or LCPR, into the raft, and would roll-off into the water for insertions.  For extractions, a husky UDT man would man the raft holding what looked like an oversized tennis racket without strings.  The swimmers would line-up at a given interval, one behind the other, and hold up their arms.  As the pick-up boat moved down the line the swimmers stuck their arms into the “tennis racket” and were hauled onto the IBS lashed to the side of the moving boat.  The swimmer would exit the raft for the pick-up boat to allow another swimmer to be recovered.


This means of extraction was used from the end of World War 2 through the Korean War and into the 1960s.  However, the method exposed the boat, crew, and swimmers to hostile fire (the pickup boat was limited to 12 knots) and swimmers readily sustained injuries while being brought aboard.  In the early 1960’s the Navy fielded two gas turbine-driven boats that employed the Fulton recovery system to replace the LCP/LCP(R)/LCPL and IBS combination.  These boats were the Landing Craft, Swimmer Reconnaissance (LCSR) and a smaller, lighter version called the LCSR(L).  The LCSR boats were not used by UDT/SEAL teams in Viet Nam.



Above.  A portside shot of a 52-foot LCSR.  Seven LCSR and two LCSR(L) boats were built.   Uniflite of Bellingham, WA built the fiberglass LCSR. The LCSR and LCSR(L) were the Navy’s first attempt to put gas turbines in small craft.  The effort was not entirely successful. The LCSR turbine exhaust had a nasty habit of setting fire to wooden piers or small boats that came alongside.  The clutch mechanism for connecting the output of the turbines to the shafts was temperamental.  Props had a nasty problem of throwing blades – into the lazerette where the steering gear was located.  Low battery output caused hot starts on the turbines that lead to shortened engine life. (Photo: US Navy)



One of the two 36-foot LCSR(L) craft showing the exhaust stacks for the gas turbine engines.  One boat was fiberglass and the other was aluminum.  LCSR(L)-1 was built by Harbor Boat Co. (Harco) of San Diego, CA and LCSR(L)-2 was built by Henry C. Grebe Co. of Chicago, IL.  The LCSR(L) had similar problems to the larger LCSR.  The variable-pitch mechanism in the propellers was weak.  The hydraulic winch used for recoveries refused to work on the aluminum-hulled LCSR(L).  The electric winch installed on the fiberglass-hulled LCSR(L) used for recoveries worked fine for about 3-4 recoveries and then caught fire.   (Photo: US Navy)


The LCPL was a general-purpose craft.  It was used as a picket boat to help guide other landing craft during amphibious operations, it was used as a captain’s gig on ships, or when really spiffed-up as an admiral’s barge.  The LCPL Mk IV was a conventional steel- hulled boat with a cabin mid-ships.  The cabin was used as a conning station and as a weather cover for the transportation of personnel.  As the wartime LCP and LCP(R) boats were phased-out in the late 1950’s, the LCPL became the workboat for UDT units.  When attached to ships, the LCP, LCP(R), and LCPL were usually employed on converted World War 2 destroyer escorts called APD’s (high-speed destroyer transports).  It was usual that the UDT detachments provided their own boat crews for operations or acted to train ship’s company boat crews from the APD’s for their particular kinds of operations.



A late 1966 photo shows a nest of Mk IV LCPLs is tied up along side the USS BELLE GROVE (LSD-2).  These steel hulled 36-foot boats are stock except for the mounted machine guns.  The first SEAL units in Vietnam used boats similar to this.  (Photo: Bruce Shewbrooks)



A 1967 shot of the High-Speed Destroyer Transport USS DIACHENKO (APD-123).  Converted from World War 2 destroyer escorts, the APD carried four 36-landing craft and were very useful for supporting UDT operations with their 5-inch and 40mm guns.  However as SEAL operations moved ashore and onto the rivers and canals of Vietnam, the deep draft ships could not follow and it was evident that the LCPL, even in a heavily modified form, needed replacement with more specialized craft.  (Photo: Al Cataneo)


Late 1966 and early 1967 saw the first deployment of UDT and SEAL teams to the Viet Nam war zone.  At first, the UDT/SEAL operators made do with a scrounged collection of small boats:


There was the ubiquitous IBS and its parent, the LCPL.  UDT/SEAL operators modified the LCPL Mk IV to carry two .30 and two .50 machine guns, and one Mk 18 crank-operated 40mm grenade launcher (on the boat’s centerline, between the two .30 machine guns).  The boat was pretty much stock and there was none of the specialized armor or armament that characterized other such boats later in the war.


Similarly, they acquired a mechanized landing craft (LCM-6) and modified it to carry three .30 and four .50 machine guns, a 57mm recoilless rifle, a 60mm mortar, and an Mk 18 crank-operated 40mm grenade launcher.


Below.  A rare 1967 shot of the LCPL Mk IV used by SEAL Team ONE in Viet Nam.  The boat is pretty much stock with .50 BMGs fore and aft with .30 BMGs mid-ships and the Mk 18 on the centerline, between the two .30 BMGs.  (Photo: Chuck LeMoyne).



Above.  Another rare 1967 shot of the LCM-6 modified by SEAL Team ONE.  Looking aft from the bow, the Mk 4 Mod 0 60mm mortar is covered by a flak jacket and canvas cover, while the Mk 18 Mod 0 40mm (Honeywell) grenade launcher is just in back of the flak jacket.  The mid-ships .50 BMGs are shown; one just behind the Mk 18 and the other under a camouflage cover.  Both these guns were mounted on the ground M3 mounts.  The M18A1 57mm recoilless rifle is mounted just above the rear canopy.  Mounts and shields for two of the three aft .30 BMGs are clearly seen; the left gun is at full depression while the barrel of the right gun is slightly elevated with a cloth covering the receiver (just above and behind the camo cover for the .50 BMG.  Not shown are the two .50 BMGs on either side of the bow ramp or the .30 BMG that fired directly aft.  (Photo: Chuck LeMoyne)



Above.  A later 1967 portside shot of the LCM-6 modified by SEAL Team ONE  known as the “Mighty Mo. Looking aft from the bow, there are two .50 BMGs on either side of the bow ramp, a Mk 4 Mod 0 60mm mortar and a Mk 18 Mod 0 40mm (Honeywell) grenade launcher on the raised platform.  The mid-ships .50 BMGs are shown; both these guns appear to have been fitted with armored shields.  The M18A1 57mm recoilless rifle is mounted just above the rear canopy.  Mounts and shields for the three aft .30 BMGs are clearly seen.  This boat was operated out of Nha Be.  It was joined by two purpose-built Heavy Seal Support Craft (HSSC) operated by Mobile Support Team (MST) personnel from Can Tho and My Tho in the Spring of 1967.  LT John Kerrey and several others were wounded when the “Mighty Mo” took a mortar round in the well deck.  (Photo: Jerry Clark)




The standard 56-foot LCM Mk 6 as it was before SEAL Team ONE modified it.  (Drawing: US Navy)


Two things were apparent from the first: (1) the UDT/SEAL operators needed better, purpose-built craft with more firepower and armor, and (2) the boats needed to be driven by sailors – other than UDT/SEAL operators – who were familiar with the kind of tactics that were being developed.  This need developed into what was called PROJECT ZULU.


Volunteers from BSU-1 deployed to Viet Nam to experiment with the support of UDT/SEAL operators under wartime conditions.  They began with two LCM-6, two Mk IV LCPL’s and four Boston Whalers (with silenced outboards).  The Whalers were fitted with a pedestal mount that could take either a .30 or 7.62mm machine gun.  The LCPL’s and LCM-6 (now christened the Heavy SEAL Support Craft) were modified to accommodate numerous gun positions and had armor added to protect vulnerable spaces.  The heavily modified LCPL’s and HSSC were based at Can Tho and later My Tho.  Their operational area was a swamp, much like the Florida Everglades, that was infested with Viet Cong guerilla units.  This was the RSSZ [Rung Sat Special Zone].  It was here that the early SEALs and BSU-1 (now called Mobile Support Teams – MST) sailors learned the trade of war.



A Boston Whaler with an all-Vietnamese crew on patrol.  (Photo: Vietnamese Navy)


With the exception of the Boston Whalers, the LCPL and HSSC were very slow.  The problem with the Whalers was their total lack of armor and firepower for SEAL operations.  Something better was needed.



The STAB used by SEAL Team TWO in 1967.  (Photo: US Navy)

A bow-on shot of a well-used STAB.  (Photo: Fred Schuler)



SEAL Team TWO and MST brought three STAB (SEAL Team Assault Boats) to Viet Nam in late 1967 for evaluation.  The STAB was a modified Boston Whaler commercial design.  It had twin outboards, some armor, and more mounts for M60 machine guns.  It was not entirely successful and was an interim design at best.  These boats were used until worn-out and discarded for purpose-built craft.




The old and the new -- a MST-modified LCPL and a new LSSC are tied up to a barge in the Bassac River at Nha Be or My Tho in late 1968 or early 1969.  This LCPL has a single .50 BMG forward with a pair of .50s mid-ships.  Viet Nam was always hot with humidity that seemed to take your breath away along its rivers and canals.  The only exception was during the Monsoon season, when temperatures could drop twenty degrees or more to the point you were cold, you shivered, and your teeth chattered.  From looks of the boat crews, this is not the Monsoon season.  (Photo: Rick Erwin) 


Meanwhile, modifications were being done to the LCPL’s in-country (now four) and the HSSC as the result of combat lessons learned.


The LCPL was the workhorse of the MST units during late 1967 through 1969.  Modifications included cutting a hole in the foredeck for single or twin .50 machine guns or a 7.62mm Mini-gun.  The deckhouse was cut down to reduce its visibility.  A canopy was erected over the interior to shield the occupants from the tropical sun.  A Raytheon 1900 search radar was fitted to help identify small craft and assist navigation.  A 60mm Naval mortar, three more .50s or two .50s and twin M60 machine guns, several single M60 machine guns, a Mk 20 automatic 40mm grenade launcher, and AN/TVS-2 night vision gear.  The next series of photos are show details of the LCPL belonging to LTjg  John Engstrom’s Detachment ECHO in operations at Nam Can before the building of SEA FLOAT (December 1968 to June 1969).



A bow-on shot of Detachment ECHO’s LCPL.  Note the cargo net tied on the bow to assist the SEALs when reboarding the craft.  This boat has an interesting in-country modification (and the only one of the four LCPL’s to receive it): the 7.62mm Mini-gun.  To its rear is the Mk 4 Mod 0 60mm Naval mortar.  To the left of the crewman are an Mk 20 Mod 0 40mm automatic grenade launcher and a Browning .50 AN/M2HB machine gun (one of two).  ECHO’s LSSC is just visible in the left foreground.  (Photo: John Engstrom)


A shot of LTjg Engstrom’s LCPL extracting from a beach on the Song Cau Lon near Nam Can.  The SEALs are shown in their ready-reaction positions.  Whether this was part of an actual operation or staged for the camera is unknown.  Most SEAL operations like this were done at night to minimize the threat of detection.  (Photo: US Navy)



Detachment ECHO’s LCPL with its bow on the beach and its SEALs ashore.  The dense jungle is one reason why the Commander Naval Forces Viet Nam (ComNavForV) Elmo R. Zumwalt ordered defoliation of the Song Cau Lon near Nam Can to prevent ambushes of friendly forces by the VC and NVA forces.  Note that the draft of the LCPL prevents it from getting close to shore and that the SEAL operators will have quite a lift to get back on the boat (hence, the cargo net over the bow in another picture).  (Photo: US Navy)



A close-up view of the Mini-gun and gunner on Detachment ECHO’s LCPL.  The Mk 4 Mod 0 60mm mortar is in the foreground.  (Photo: John Engstrom)




The Detachment ECHOL LCPL underway with the SEALs aboard.  The location is unknown but the buildings suggest along the Bassac River near Binh Thuy.  The LCPL was not a fast boat as shown by how she plows through the water.  (Photo: US Navy)




The Detachment ECHO LCPL shows its battle damage after a dust-up with the local VC/NVA forces.  Just to the left, middle of picture, above the waterline is the hole from a B-40 rocket.  Also visible are numerous bullet impacts on the hull.  This boat reflects the upgrades in armament while at Nam Can.  Note the twin M60 machine gun mount to the right of the .50.  The strange device above the forward M60 is an AN/TVS-2 “Starlight” passive night vision scope. (Photo: John Engstrom)



SEA FLOAT in late 1969 or early 1970.  The barges were oriented East to West in the Cau Lon River.  The MST quarters are directly opposite the boat wake on the Northeast side.  The next two long huts were for three SEAL platoons and one UDT detachment.  Craft at SEA FLOAT were a mix of Swift boats (PCF), river assault craft, coastal patrol junks, and two gun boats – an American PG and a Vietnamese LSSL.  These large craft provided security for the barges and anchored about 1,000 yards from either end.  (Photo: Ed Lefebvre)



The extent of defoliation along the river at SEA FLOAT to prevent the VC/NVA from ambushing friendly forces is very apparent in this photo.  This did not prevent the bad guys from shooting at us on the river – it merely made it harder for them to hide and get away with it.  (Photo: Bob Stoner)


The next series of photos show the result of PROJECT ZULU: the Heavy Seal Support Craft or HSSC.  (The HSSC evolved as experience was gained in fighting the enemy along the river.  Compare this boat with the Nha Be LCM-6 of SEAL Team ONE.



The HSSC as she looked at the time of PROJECT ZULU.  She does not yet have the later in-country modifications such as bar armor.  Note the standoff-plates around the conning station of the boat (beneath the radar dome).  The solid plates would eventually be supplemented by bar armor that was lighter and more effective.  Likewise, the canvas covering over the well deck would give way to a steel helicopter pad and a canopy would soon be erected over the conning station to protect the crew from the Vietnamese sun.  The armored bulge around the engine spaces is also absent in this picture.  Note the two LCPL’s of PROJECT ZULU nested outboard of the HSSC.   (Photo: US Navy)



A close-up of the HSSC’s conning station.  Note the armored cupola with vision slits and the improvised canopy to protect the crew from the sun.   The radar dome appears to have been relocated in this photo.  Two members are “catching some rays” on this river transit.  (Photo: US Navy)



Another shot of the HSSC seen from the bow ramp.  Note the inner blast doors to protect the well deck when the ramp goes down.  There are two 7.62mm Mk 21 Mod 0 Browning machine guns directly to the rear of the Mk 2 Mod 0 81mm mortar (the basket-enclosed breech end is just to the left of the sailor wearing the helmet and flak jacket).  Behind the Mk 21’s are the four .50 machine guns (two per side) and there was a single .50 firing out the rear of the conning station.  The well deck does not yet have its canvas cover replaced by the helicopter pad in this 1968 shot.  (Photo: US Navy)



A good side view of the HSSC in early 1968 shows protection upgrades around the engine compartment to defeat rockets and recoilless rifle rounds.  No bar armor is fitted at this time and the cloth cover over the well deck has yet to be replaced.  It has yet to receive its 106mm recoilless rifle and Mini-gun. (Photo: US Navy)



The HSSC in mid-1969, before the bar armor modifications.  Bar armor was standard on the HSSC assigned to SEA FLOAT.  In this shot, the solid helo pad has been added over the well deck.  A M40A1 106mm recoilless rifle is mounted on the pad and a 7.62mm Mini-gun has been added in a tub at the front of the pad to give the HSSC more frontal firepower.  The Mk 2 Mod 0 is in front, barrel pointing down to drain any rainwater.  By the time the HSSC got to Nam Can [SEA FLOAT/SOLID ANCHOR] the mortar had been upgraded to the Mk 2 Mod 1 with the .50 M2 machine gun over the recoil cylinder.  Ordnance carried by Nam Can’s HSSC was the was the 81mm/.50 forward, the Mini-gun in a gun tub behind it, two pairs of .50 and two pairs of M60 machine guns on either side of the well deck, a 106mm recoilless rifle on top of the helo pad, and a .50 “stinger” machine gun at the rear of the conning station.  This HSSC was later sunk in a storm while alongside the ARL that was anchored off Square Bay at the western entrance to the Song Cau Lon  (Photo: US Navy)




The other (second) HSSC was similar in appearance except that it had twin .50 M2HB machineguns in place of the Mini-gun.  Ordnance carried by this HSSC was the was the 81mm/.50 forward, twin .50 BMG in a gun tub behind it, two pairs of .50 and two pairs of M60 machine guns on either side of the well deck, a 106mm recoilless rifle on top of the helo pad, and a .50 “stinger” machine gun at the rear of the conning station.  This HSSC was later turned over to the Vietnamese Navy.   (Photo: Vietnamese Navy)



“Fire in the hole!”  Steve Elson, a Nha Be SEAL took this photo of target practice from the helo pad of the HSSC.  Note that everyone with experience is protecting his ears from the back blast of the M72 rocket launcher (or LAW – light anti-tank weapon) being fired.  The M40A1 106mm recoilless rifle is swung to starboard in preparation for firing.  This beast was MUCH louder than the M72!  (Photo: Steve Elson)


 The MST sailors and SEALs learned that the B-40 rocket and 57mm or 75mm recoilless rifles were some of their worst enemies.  By late 1969 the HSSC had benefited from the anti-rocket protection afforded to the craft of the Mobile Riverine Force.  Bar armor made from concrete reinforcing rods was placed on hangers a foot away from the hull and pilothouse of the boat.  The bar armor would detonate the warhead of the rocket or recoilless round to prevent its penetrating into the interior.


By late 1967 it was obvious that the 17-foot Boston Whaler was unsuitable, as was the longer STAB trimaran.  The LCPLs and HSSCs certainly had firepower, but they were very slow.  Additionally, their size and draft prevented them from going into the smaller canals.  And so it was back to the drawing board.  What came forth were the two boats that became the workhorses of the MST/SEAL units for the remainder of the war in Viet Nam.  These boats were the Light SEAL Support Craft (LSSC) and Medium SEAL Support Craft (MSSC).  Grafton Boatworks built 16 LSSC’s and Atlantic Research built ten MSSC’s.


Grafton also built 22 of a slightly larger, improved [aka Mk II] version of the LSSC called the Strike Assault Boat or STAB.  [Note: there are two STAB boats of different designs used by different operators.  This has confused many people and authors over the years.]  These STAB’s were assigned to STAB Squadron [StabRon] 20 that operated around the “Parrot’s Beak near the Cambodian Border in 1970 and not to MST.



The second STAB (aka Mk II LSSC), like the original LSSC, was also built by Grafton Boatworks.  It was two feet longer and used MerCruiser outdrives (props) instead of Jacuzzi pump jets.  These STAB’s were used exclusively by StabRon 20 and were not used by MST.  These two STAB’s are alongside the USS BENEWAH (APB-35) on the upper Mekong River.  (Photo: Tom Lefavour)



A slightly damaged photo of a STAB beached.  The area is apparently secure since the guns are still covered.  (Photo: Don Basillion)



Morning on the Grand Canal (between the upper Mekong and Vam Co Tay Rivers.  Dawn is just breaking and it is time to secure from waterborne guard post and go home.  It is very easy to confuse the STAB and the LSSC as can be seen from the photos as the layouts were very similar and there was only two feet difference in length.  STAB’s tended to carry more armament than their LSSC cousins.  The LSSC partially relied on the weapons of its SEAL squad to enhance their firepower.  (Photo: Don Basillion)



The LSSC of MST Detachment ALPHA comes back in from an operation with SEALs of X-Ray platoon aboard.  It appears that the radio operator standing on the bow may have a problem judging from his expression and posture.  Note the diverse “uniforms” worn by the SEAL and MST operators.  The general rule was that if it worked you used it; if not, you didn’t or found something better.  Hence, SEALs wearing Levi’s instead of camouflage trousers. (Photo: Gary Hunt)



Low tide at Nam Can.  The LSSC of Detachment ECHO has its underwater vitals exposed for maintenance.  Even routine tasks could be difficult due to the lack of support equipment.  Note the Jacuzzi pump jets and the step that are different from the later STAB.  The SEA FLOAT base was not yet constructed.  (Photo: John Engstrom)



BM3 Dan Savage of Detachment GOLF (September 1970 to March 1971) shows off the battle damage to his LSSC: a B-40 rocket hit just below the pad eye.  The pad eye deflected the blast away from the crew and no casualties occurred.  (Photo: US Navy)




Close-up of the B-40 hit on the Detachment GOLF LSSC.  The rubber railing that ran along the edge of the deck on the LSSC is clearly shown in this picture.  (Photo: US Navy)



An LSSC and LCPL underway for a SEAL operation.  A Vietnamese LDNN (SEAL) is on the bow.  The SEAL facing the camera clearly shows his subdued UDT life jacket.  In this 1968 photo, the radar has yet to be removed from the LSSC.  (Photo: US Navy)



A classic SEAL insertion from the LSSC.  The lead SEAL carries the Ithaca M37 12 gauge shotgun.  The second SEAL is barefoot to confuse VC/NVA trackers.  (Photo: US Navy)



Not all SEAL extractions were easy; sometimes you had to push the boat [here an LSSC] off the beach when the tide started to drop.  The mangrove swamp is typical of the Mekong River Delta and the canals of the Ca Mau Peninsula.  (Photo: US Navy)



Detachment ECHO’s LSSC at Nam Can.  Note that it still has its radome in this early 1969 shot.  Here, an improvised twin M60 mounting has replaced the single rear .50 BMG set-up.  (Photo: John Engstrom)



A January 1971 photo of Detachment CHARLIE’s LSSC at SOLID ANCHOR after an ambush.  The SEAL advisor LT Jim Thames and Vietnamese LDNN interpreter were killed and the MST-2 OIC LTjg Bob Natter and several others were wounded.  The lower of the two B-40 rocket hits punctured the fuel bladder and severed the pump gate control cables so that the boat could only go forward with no neutral or reverse.  Note that the radar radome has been removed from this boat.  (Photo: Don Crawford)



A good interior shot of the MST-2 Detachment at Nha Be in 1969.  (Photo: Terry Knott)



Two of the Nha Be LSSC’s nested along the river.  Note the mixed armament carried; both M60 and M60D 7.62mm machine guns, an M2HB Browning .50 machine gun (right); and a Mk 20 automatic 40mm grenade launcher (left foreground).  (Photo: Terry Knott)



Interior shot of the two nested Nha Be LSSC’s.  The throttles are just below the radome.  Note the C-ration cans clipped to the sides of the M60D machine guns to help the belted ammunition feed to the gun.  This was a frequent field expedient in Viet Nam for M60 machine guns.  Shown is one of the bench seats (occupied by helmets and ammunition boxes) that  were for MST crew and SEALs.  Normal crew for the LSSC was 2 to 3 MST and up to 6 SEALs.  This made for a very crowded interior when everyone was aboard.  (Photo: Terry Knott)




A flying LSSC?  Certainly!  In this photo, an LSSC is about to be airlifted by an Army CH-47 “Chinook” helicopter.  The idea was to insert and extract the LSSC into areas that the VC/NVA considered secure from enemy forces.  The idea was tested three times; the first two flights were successful and the third resulted in the jettison of the LSSC when it began an uncontrolled oscillation beneath the helicopter.  A fourth flight was not attempted.  None of the attempts involved combat operations.  (Photo: US Navy) 



The LSSC in flight beneath a CH-47 helicopter.  This unique view of the LSSC shows why it was able to go into very shallow water – there was nothing projecting below the bottom of the hull due to its water-jet propulsion system.  The inlet for the portside pump is seen near the end of the hull.  (Photo: US Navy)


The supplement and then replacement for the venerable LCPL was the Medium SEAL Support Craft (MSSC).  Ten were built by Atlantic Research for the Navy under a 1968 contract and came into use by MST in late 1969.  The MSSC could carry a whole SEAL platoon plus its MST crew at speeds over 30 knots.  The MSSC was built of aluminum like its LSSC stable mate, but instead of the two 427 cu. Inch Ford engines and Jacuzzi pump jets, the MSSC used 427 cubic inch Chevrolet engines with MerCruiser stern drives (outdrives).  The MSSC could not go into the shallow waters the LSSC could, but the thrust of its propellers was more than that of the Jacuzzi pumps in the LSSC.



Stateside shots:  The MSSC at the Boat Support Unit ONE pier in Coronado, CA.  Note that the boarding steps on the front of the MSSC have not been damaged.  The boarding steps were the most easily damaged feature of the craft and so they were supplemented by a nylon cargo net when on operations in Viet Nam.  (Photo: US Navy)




A public relations shot of the MSSC dropping off SEALs on Silver Strand Beach near the Amphibious Base at Coronado, CA.  (Photo: US Navy)



Coronado’s MSSC shows off her top speed in San Diego Bay.  The Naval Base (32nd Street) is in the background.  (Photo: US Navy)



Detachment ALPHA’s MSSC getting ready to move out on a daylight operation from Ben Tre (during October 1970 to March 1971).  (Photo: Gary Hunt)




Stern shot of Detachment ALPHA’s MSSC heading out on the same daylight operation from Ben Tre.  (Photo: Gary Hunt)



Detachment ALPHA’s MSSC at top speed on the river near Ben Tre.  Note the cargo net draped over the bow to assist SEALs in getting aboard the boat on extraction.  (Photo: Gary Hunt)





CWO Shepherd of Detachment ALPHA and the crew of their MSSC at Rach Soi.  Note the Naval Mk 4 Mod 0 60mm mortar on the starboard weapons mount.  This installation was not common.  (Photo: Gary Stubblefield)



Detachment ALPHA’s  MSSC at the Rach Soi docks.  Other river craft in the photo are a Boston Whaler (foreground), PBR (next to MSSC), and armored LCM Mk 6 landing craft (behind PBR).  (Photo: Lee Wahler)



Interior of Detachment ALPHA’s MSSC looking aft shows off the amidships .50 BMG’s and the aft 7.62mm Mini-gun.  Note the M79 grenade launcher behind the bungee cord across the Mini-gun’s ammo container.  The 40mm grenades are in the bandoliers just to the left of loop in the Mini-gun’s feed chute.  The box [left foreground] with the large “C” is for C-rations, while an insulated cooler is directly in back of it.  The flak curtains on either side of the well deck are clearly shown in this photo.   (Photo: Gary Hunt)


A recycled .50 machine gun.  This gun was captured from the VC and put back to work against them.  The hybrid AN/M2-M3 (Aircraft) Browning machine gun is on Detachment CHARLIE’s MSSC. (Photo: Bob Stoner)



The MSSC’s of Detachments CHARLIE and BRAVO nested on the beach at SOLID ANCHOR in October of 1970.  In the Spring of that year, Detachment CHARLIE’s MSSC (foreground) took a hit with a B-40 rocket just above the water line and behind  the white fender that severed the steering cables (narrowly missing the fuel cell), punched through the interior armor and flak blanket, and wounded one of the SEALs.  The emergency tiller was quickly attached and the boat was maneuvered out of the ambush.  One of CHARLIE’s two LSSC’s is just behind the folded down windshield.  The remains of the old SEA FLOAT barge complex can be seen to the right, still anchored fast in the Cau Lon River.  (Photo: Bob Stoner)


Below.  Detachment CHARLIE’s MSSC hull showing the B-40 hit. (Photo: Fred Schuler)




Interior shot of the MSSC showing damage to the ceramic armor ties and flak blanket.  (Photo: Fred Schuler).