Captain Koster is a retired submarine officer who served on both Submarine Group Eight staff and on the staff of CINCUSNAVEUR. He now lives in Winter Springs, Florida.
Author’s note: The contributions of the Skipper, Capt Herbert O Burton, USN Ret, have been extremely valuable in preparation.
The letter from Frank Uhlig, Jr. in the January Review raised the issue of putting expensive SSNs in shallow water in support of SEAL operations and information gathering. He cited the vulnerability concerns expressed by ADM J. L. Holloway in planning and executing a surface ship raid on the entrance to Haiphong harbor in Operation Lion’s Den in late August 1972. The Admiral’s excellent article in the August 2004 issue of Naval Historv provided a blow-by-blow of the mission involving two cruisers and two destroyers in a surprise shore bombardment raid close inshore. The Admiral, then COMSEVENTHFLEET, was embarked as an observer in the NEWPORT NEWS, the big-gun cruiser involved. The force was attacked by three P-6 MTBs on retiring from the area that were destroyed by gunfire and supporting aircraft. The issue of submarine operations in littoral waters resurrected memories of a six-week lifeguard operation in 1965 mostly in the approaches to Haiphong to seaward of Lion’s Den. Mr. Uhlig’s question is valid, but clearly one that has been faced before.
SALMON (SS573) was one of perhaps halfa dozen submarines assigned, off and on, to lifeguard missions in 1965 to support ROLLING THUNDER air strikes on North Vietnam north of the 191h parallel. A submarine picked up one downed pilot in the Spring off Bach Long Vi Island in the north central Tonkin Gulf (USS CHARR SS328 on 29 March ’65). Submarine participation started for brief periods in March and terminated by December. By then rescue helicopters, hot-refueled by surface ships on NORTH SAR and PIRAZ stations in the northern Gulf, were demonstrated to be far more effective than submarines could ever be in that environment.
SALMON, I believe, served the longest time on a dedicated lifeguard mission-six weeks continuously from late-September to early November ’65. We were well prepared, knowing our first operation after deployment from San Diego would be as lifeguard. We studied the few previous reports, all the charts, coast pilots, meteorological and intelligence assessments and everything else we could get our hands on. AMS/JN Charts were added to our inventory for land recognition. And the boat was augmented for self-defense on the surface. Two water-tight, ready-service ammo lockers, removed from a mothballed fleet boat, were installed on the navigation deck and heavy machine gun mounts were welded on each side of the large bridge cockpit. We received 50-caliber machine guns, and trainers from PHIBASE Coronado taught us basics of 50-caliber marksmanship and weapon cleaning. We u surface and gun crew drills on the transit to Subic in late August. These involved hauling the machine guns up through the bridge trunk and mounting, retrieving ammo boxes from the ready service lockers, and firing a few practice rounds. All were timed and we practiced until it went smoothly. The crew was most enthusiastic and everyone wanted to get qualified. As navigator during this period details are easily refreshed with current charts and in discussions with shipmates. Lessons-learned were documented in our post-mission report and many are recalled.
Lifeguard areas, 24-mile diameter circles, were positioned north of the l 9’h parallel generally tangent to the 12 mile limit to support ‘Alfa strikes’ from carriers in the Gulf. These gave the pilots a ditching target and provided a safe haven. Several are shown on the chartlet reco11stn1cted to general locations from memory. Area Hotel is the most accurately positioned as SALMON occupied it most of the time on station. It is also an area not previously occupied.
Current charts of the area indicate soundings in meters based on lowest, low water; even considering the four-meter diurnal tidal range, the soundings are somewhat less than those encountered during SALMON’s operation. Soundings on charts used 40 years ago were in fathoms and feet. In researching the current charts, sedimentation from the Red River (Song Hong and Song Duong) has increased significantly in recent years as a result of extensive up-river deforestation.1 We would be hard pressed to operate in these charted waters today as SALMON did.
We positioned in response to direction from the operational commander, COMSUBFLOT SEVEN/ CTG70.9 in Yokosuka, based on assigned target packages and scheduled times for the air strikes. This was delivered by FLASH message, repeated on the submarine broadcast with the normal 12-hour assured-delivery cycle. In my recollection, we always copied the message on first transmission. One occasion of late notification required a to-knot snorkel transit to Area Golf partly during daylight to cover the strike. (This makes the case for nuclear power, but waters were shallow and fishing hazards abundant.)
No special submarine coordination nets were established. We monitored the CTF 77 intra-ship tactical circuits along with aircraft strike and SAR/emergency frequencies. Our one occasion to communicate was to rendezvous for the long awaited mail transfer when we left station.
The ROE are not memorable; we felt we had all the flexibility needed to rescue downed flyers. By the end of the operation we considered the most likely scenario for our participation would be if one of the SAR helos went down while feet wet.
SALMON made initial landfall on Hon Me Island after a 200 mile submerged transit across the mouth of the Gulf. We then moved north covering several strikes as we proceeded to Area Hotel where we were assigned for most of the time. Monitoring the downlink of a successful pilot recovery by helo well inland provided a great sense of purpose for the operation. The transit exposed us to local conditions and we adjusted to operating in shallow water-less than 100 feet for most of the operation-and the fathometer was used as needed without fear of detection throughout. Trimming was a demanding task in the shallow, sometimes brackish water of the Red River outflow. (At 350 feet LOA, anything greater than a three down or a two degree up angle risked putting the bow or stem in the mud much of the time.) Fortunately, seas were generally calm during the operation. Anything much more than a moderate swell would have forced us to deeper water.
Relatively few fishing boats were encountered in the transit; untended long-line fishnets proved to be the biggest hazard. Strung across the current that set to the southwest along the coast, nets were sometimes marked by poles at the ends, other times by floats. Sighting a single pole forward of the beam prompted a tum to seaward and a diligent search for the second pole, adjusting the tum to clear both. We snagged a net early on, detected by a float thumping on the hull. We surfaced that night to clear it and found, to our surprise, imbedded fishhooks making removal a time-consuming task. Later we observed a school of sea snakes frolicking on the surface-recalling that a boat had previously surfaced in the Gulf with a sea snake in the shears that reportedly fell on a lookout. The deadly snakes were said to die on encountering air … right! Those going topside for every surfacing thereafter donned a rain parka and gloves.
Coastal navigation, essentially piloting, relied primarily on a hand DR on a chart overlay, with the MK 19 plotter set to the chart scale. With erratic visibility, nondescript coastal features, a generally flat bottom with a very gradual slope to seaward, no RDF, and occasionally a weak LORAN line, it took a while to develop confidence in our position. Sparse charted soundings in fathoms and feet indicated a 15-fathom curve that roughly bisected the SAR areas but included no reliable information for contour navigation. Variable currents influenced by the monsoons and diurnal tides, coupled with our slow speed, added to challenges of maintaining a good DR position. When visibility cleared the Chief Quartermaster identified several distant peaks from topography on a Jet Navigation Chart that provided good bearing lines for a fix. On entering Area Hotel we found a reliable NA VAID-Grande Norway light. It marked the eastern entrance to Haiphong channel and was normally illuminated. Visibility permitting, dipping the light provided a reasonable 21 mile range arc at night. Fortunately, our first fix using this method positioned us as having entered the area from the south, clear of the most prominent charted feature in Area Hotel-a 12-fathom pinnacle in the northwest quadrant. We carefully avoided that region and fortunately soundings always seemed to indicate water slightly deeper than shown on the charts we used.
Area Hotel was positioned on the primary shipping lane serving Haiphong from the Hainan Strait about a hundred fifty miles to the east. A second lane, generally less traveled, extended southward around Hainan. Most ME RS HIPS were detected at night, apparently the result of the daytime air raids.
Hotel also straddled a major fishing area served from many coastal villages in the Red River delta. With water temperatures almost 90 degrees and heavy nutrient content in the river outflow, the biologics, largely shrimp and carpenter fish, contributed to a very high ambient noise level. This situation worsened in the relatively frequent rain showers of the south Monsoon. Fortunately, PUFFS punched through the ambient noise in many cases. (A retired Senior Chief Sonarman recently described those conditions off Haiphong as being the worst he encountered in 22 years. 2) All combined with the shallow water to influence operating procedures in the area. Predeployment preparations had provided only the basics as we were the first to occupy Hotel.
The driving operational factor was to be in a ready position at the announced time of’ Alfa strikes’-by recollection, most occurred in the early morning or late afternoon. This position was ideally to be clear of contacts so that both scopes, and occasionally the ESM mast, could be used. We often had only 20 to 30 feet of water beneath the keel in these areas. (Remaining undetected was para-mount, unless and until required to conduct a rescue.) From there, visibility permitting, we occasionally observed helos that were always present for the strikes, loitering off the coast and readily available if a plane went down. We considered helo movements to be an early indicator of SALMON’s potential involvement. The crew was keyed to all events. Only when the aircraft departed the area did we detect radio transmissions, and then the pilot chatter seemed near continuous-understandably.
The ubiquitous fishing boats presented problems not fully appreciated beforehand. Most were relatively small, about 30 feet with one and sometimes two masts, not the characteristic fishing junks found off Hong Kong. Many towed a sampan to tend nets.
Most were under sail or drifting, and only a few were motorized-distinctive one-Jungers. No large trawlers here. (Fortunately PUFFS was relatively unaffected by biologics and it was often the first to detect the one-lung fishing boats and merchants.) Several times each week before dawn large groups migrated out from land, probably riding the diurnal tides; they always seemed to straddle our track as we proceeded to our ready position. Most seemed unlighted or with a dim lantern. In the evenings large numbers would return to shore most often across our intended track to a night snorkel area.
At first light one morning soon after arriving in Hotel we found ourselves amid what seemed to be hundreds. Our Skipper, CDR Herb Burton, described the situation best: ” … we’ve got ’em surrounded … “. SALMON seemed to .. surround ’em” frequently thereafter.
We saw no evidence of the long-line, largely untended nets observed in transit. And we were fortunate to clear the smaller tended nets-at least we had no sign of dragging any boats astern–always a potential problem amid fishing fleets.
Periscope procedures and close-contact management skills were rapidly honed to avoid detection while winding our way through these seemingly endless flotillas. Minimum scope exposure and very short observations, often in low power, were essential. The conning officer marked contact bearings and estimated ranges that were recorded on a laminated maneuvering/tote board for reference. A stopwatch assured short exposures and the plotter was set at 500 yards to the inch to keep track of major concentrations. (The Contact Evaluation Plot, the bearings-only presentation adopted from the British in 1971, would have been a valuable tool in these situations.) Fortunately most contacts were at slow speed or stationery; we focused largely on those with visible waterlines well inside the horizon-less than l 000 yards. These would sometimes number a dozen or more. With very little water beneath the keel the boat had no place to duck, and running with the scope down for more than two minutes created new hazards. (Those weak-of-knee rapidly gained leg muscles on the scope.) Additional problems resulted when visibility closed in with rain or heavy mist. We were always able to maneuver through a hole to a ready position relatively clear of contacts where at least # 1 scope would provide an antenna for strike coverage. After sunset the problem was sometimes more difficult as we tried to thread through to a safe snorkel area in the gathering darkness.
High ambient noise levels contributed significantly to the problem of detecting merchant ships. One night during a snorkel shutdown to clear baffles PUFFS detected a faint merchant through the biologics-it turned out to be a bow nu11. Soon, out of the limited visibility a masthead, range light and two sidelights appeared. We were clearing the track with its bearing moving ever so slowly. We couldn’t take an angle and go deep, only plane down a few feet and lower the scope; the reconstructed bearing rate at CPA was well over 40 degrees/minute. We looked up at the ship’s deck lights-not a comfortable experience in shallow water. Many heard it through the hull at CPA and the 8QR-28 could only pick up reliable track when the ship came out of the baffles and opened.
PUFFS also detected light fast screws amid the biologics one morning that turned out to be a sma11 patrol craft with a machine gun on the foredeck-the only NVN warship we observed during the operation. It was patrolling about 3,000 yards north of our position. (Hostile encounters were frequent subjects of wardroom discussions. Our only real defense in recovering a downed pilot would be the 50 caliber machine guns. The MK 37 couldn’t be used with its six-foot ceiling cutout switch, and the straight-running MK 14 could only be used set at low speed, 31 knots, with its minimum 10 foot running depth suitable only for a larger warship not in the NVN navy 008. The hi-speed 45-knot setting would bury in the mud with its depth excursion on impulse. Other weapons were not feasible.)
The high injection temperatures and an often-oily sea surface off Haiphong created problems, first reflected in increased time for periscope upper optics to clear. Draining time of less than a second was acceptable; it increased to three seconds soon after arrival in Hotel. This required surfacing every second night as we night-snorkeled in the deeper water, 100-120 feet, toward the seaward edge of the area. At this time we cleaned and polished the headwindows coating them with a wetting agent.
We also noted sea-slime on the bridge-a situation that worsened with each surfacing thereafter. The fu11 magnitude of the problem only became apparent when we departed station. The magnetic log became erratic periodically requiring retraction and cleaning on several occasions. I also recall the engineers having to clean salt water cooling system strainers more frequently while in the warm waters.
Air temperature and humidity were high, even at night, with a smell on surfacing similar to that from open sewers in third world countries. On one occasion when the foul air was not noted on the bridge in the on-shore breeze, we ‘ventilated ship’ by taking the engine suction through the forward torpedo room hatch. That was a memorable mistake as the odor lingered near the sea surface and soon everyone was exposed to the foul air. It took a long time to get back to a good diesel-boat smell.
On surfacing in the Central Gulf for the long-awaited mail transfer on departing station we noted the extent of the sea-growth problem. Green hair almost an inch long covered the hull. When dry and bleached by the sun it turned almost white. We resembled Moby Dick on arrival in Kaohsiung. We also found barnacles, some the size of saucers, in the superstructure away from the water flow. Fortunately we were in Taiwan where local labor assisted the topside gang in removing the growth.
In summary, SALMON’S lifeguard operation almost 40 years ago demonstrates the feasibility of operating a relatively large (SALMON was the largest diesel) submarine in shallow and congested waters for extended periods. Clearly the environment is a major factor and the mission trade-offs must be favorable. Accurate pre-mission intelligence, including timely updates, is vital. Information on fishing patterns is particularly important.
The rapid response of P-6 MTBs, craft not reported in the area by pre-mission intelligence for Lion’s Den, in 1972 suggests that we could have been in serious trouble had we tried to recover a downed pilot much closer to the coast than our position at time of ditching.
From the SALMON experience, the submarine rescue function, so vital in WWII, was clearly obviated by helicopters in the Vietnam War. The boat was better suited for employment elsewhere.