South Africa to Build Damen Design Offshore and Inshore Patrol Vessels

Damen 85 meter Offshore Patrol Vessel, 1800

Damen 85 meter Offshore Patrol Vessel, 1800

Naval today reports, 

On February 15, Armscor (the acquisition agency for the South African Department of Defence–Chuck) announced Damen Shipyards Cape Town as the preferred bidder for the construction of offshore and inshore patrol boats…”

Reportedly the project includes three Offshore Patrol Vessels (OPVs) and three Inshore Patrol Boats (IPBs) for the South African Navy.

The OPVs will be Damen’s Offshore Patrol Vessel 1800 Sea Axe, illustrated above, 85 meters in length, with a beam of 13.7 meters, and a speed of 26 knots.

The IPBs will be Damen’s FCS (STAN PATROL) 5009 design, illustrated below, which is also used by the Ecuadorian and Trinidad and Tobago Coast Guards. These are 50.2 meters (165 ft) in length, 9.32 meters (30.6 ft) of beam. The South African vessels are expected to make 30 knots. An unusual feature (aside from the bow) is the use of four propellers.

I talked to someone who has ridden on a 5009 patrol vessel and he reported that it did indeed significantly reduce pitching. The tradeoff was that it was very wet forward. This should not be surprising since the design minimizes the rise of the bow when it encounters a wave.  You can see that they have attempted to counter this tendency by making the bow high and providing high bulwarks.

On the second page of this description of the design you will see a diagram of the ship which indicates that it can be fitted with up to three boats and a twin 40mm mount.

The long and slender Sea Axe hull offers exceptionally low resistance, delivering excellent fuel efficiency at all speeds

 

30mm “Swimmer” Round

30x173mm ammunition for Mk44 Bushmaster II

30x173mm ammunition for Mk44 Bushmaster II

Ran across an interesting new type of ammunition, the 30 mm Mk 258 mod 1 APFSDS-T, which appears to be designed specifically to counter Fast Inshore Attack Craft (FIAC). It uses a unique configuration to allow it to maintain high velocity after entering the water. Being an armor-piercing, fin stabilized, discarding sabot, tracer round, I suspect it might help us attack the engine rooms of larger ships. if we upgrade our Mk38 gun mounts to use the 30mm. Might be able to disable propellers and rudders as well.

In a test “…it destroyed a representative FIAC target travelling at 30kts at a range of 4.8km with the first shot.”

It would probably be good against radio controlled boats like the one in the recent attack off Yemen. General Dynamics is advertising that this “swimmer version” is currently available. This might explain why the Navy replaced the 57mm on the DDG-1000 class will 30mm guns. 

There is a bit more in the 2014 NAMMO Bulletin, on page 8 (5/13 on the pdf), under the title “The Navy’s Best Ammunition”;

The nose-shaped configuration was originally patented by the U.S. Navy and NSWC Dahlgren, but was never turned into functional ammunition. Nammo, NSWC Dahlgren and FFI (Norwegian Defense Research Establishment) carried out a comprehensive study that resulted in the final design configuration of the penetrator nose. Today, Nammo’s Mk258 mod 1 ammunition is used on board the LPD-17 and LCS class of U.S. Navy ships. This has significantly increased the fleet’s capability to defeat aerial and surface threats, as well as submerged threats like torpedoes and mines.

At the very least the 110s in Bahrain (or their Webber class replacements–whenever?) probably should have these. I’d like to see them on all the Webber Class WPCs.

How Does the Program of Record Compare to Historic Fleets

 The U.S. Coast Guard cutter USCGC Morgenthau (WHEC-722) heads out to sea from its home port in Alameda, California (USA), passing under the Golden Gate Bridge.


The U.S. Coast Guard cutter USCGC Morgenthau (WHEC-722) heads out to sea from its home port in Alameda, California (USA), passing under the Golden Gate Bridge.

A question from a reader prompted me to look at how the “Program of Record” (POR) compares with Coast Guard patrol fleets of the past.

The program of record is
8 NSCs
25 OPCs
58 FRCs
—————

91 vessels total

1990: Looking back at the “Combat Fleets of the World 1990/1991” the Fleet was:
12 WHEC 378′
32 WMECs (16×210′, 10×270′ (three building), Storis, 3×213′, 3×205′)
34 WPB 110′ (plus 15 building)
3 WSES 110′ surface effects ships
4 WPB 95′
——————-
85 vessels total
(There were also five Aerostat Radar Balloon tenders.)
 –
2000: “The Combat Fleets of the World 2000-2001” showed
 –
12 WHEC 378′
32 WMEC (13×270′, 16×210′, Alex Haley, Storis, Acushnet)
49 WPB 110′
——————-
93 vessels total.
 –
2013: “The Combat Fleets of the World, 16th Edition,” copyright 2013 listed:
 –
3 NSCs
8 WHEC 378′
28 WMEC (13×270′, 14×210′, Alex Haley)
4 FRCs
41 WPB 110′
——————–
84 vessels total
 –
Comparing the Program of Record (plus NSC #9) to the fleet of 2000: You can look at it this way,
  • 9 NSCs and 3 OPCs is more than adequate replacement for the 12 WHEC 378s
  • 49 of the FRCs is more than adequate replacement for 49 WPB 110s (and we have only had 41 anyway since the WPB 123 screw up)
  • That leaves 22 OPCs and 9 FRCs to cover for the 32 WMECs.
Conclusion: 
I think we would all be pretty happy, if we had the Program of Record fleet in place right now. It really would be a substantial improvement, but while the NSCs and the FRCs are well on the way, the first of the long-delayed OPCs will not be delivered until 2021, and, if everything goes according to plan, the last probably not before 2034, at which time even the newest 270 will be 44 years old. A lot can happen between now and then.
The 2000 fleet was, I believe, the benchmark against which the program of record was measured in the Fleet Mix Study. By 2013 we were already down nine vessels. By my estimate, by the time the last 210 is replaced it will probably be 60 years old. That is expecting a lot. Can we possibly expect that none of these ships will become unserviceable before they are replaced? Building no more than two OPCs a year is really too slow. Once the first ship is built, tested, and approved for full rate production, we should accelerate construction to the maximum. That can’t happen until at least FY2022, probably FY 2023.
By the end of FY2022 we should have already funded 7 ships. The remaining 18 would take nine years, if we buy them at the currently projected schedule. Instead we could fund the entire remaining program from FY2023-2027 by doing a single Multi-Year Procurement of 18 ships. If Eastern alone could not do it, Marinette, which like the designer VARD, is also a Fincantieri company, would probably be more than willing to build an additional couple a year, particularly if the Navy stops building Freedom class LCS/frigates.
 –
We could have the program complete by FY2030, four years early.
 –
Thanks to Peter for initiating this line of thought. 
uscgc_citrus_1984

USCGC Citrus (WMEC-300), USCG photo

storisfoam

USCGC Storis WMEC-38)

USCGC Acushnet

USCGC Acushnet (WMEC-167), USCG photo

 

Webber Class WPC Endurance?

USCGC Kathleen Moore (WPC-1109)

USCGC Kathleen Moore (WPC-1109)

A question, what is the real endurance of the Webber Class WPCs? The figure I see quoted is five days. This was the contract minimum. This is the same as listed for the 87 foot WPBs. Is this correct? This becomes important when the vessel has to make a long transit to and from its patrol area, and if we are understating the endurance, we are selling the class short.

The Webber class vessels are 353 tons full load. Similar sized ships seem to have greater endurance. The Navy’s 387 ton full load Cyclone class PCs have a nominal ten day endurance. The 300 ton Australian Armidale class patrol vessels claim a normal endurance of 21 days and 42 days maximum.

The Webber class’s endurance is not constrained to five days by fuel. The 87 ft WPBs have a nominal endurance of five days but a range of only 900 miles. The Webber class have a range of 2950 nautical miles. Obviously you don’t want to run the ship down to zero fuel, but at ten knots, it would take 295 hours or over 12 days to go 2950 miles. Even at 14 knots, it would take almost nine days to go 2950 miles. Additionally, it is the nature of Coast Guard missions that cutters frequently loiter as low speed which potentially adds patrol time.

A recent news release caught my eye. It reported the results of a 19 day patrol by USCGC Kathleen Moore (WPC-1109). She almost certainly refueled at least once, but did she replenish three times?

We have had these little ships long enough that we should have a revised opinion of their endurance based on experience. Any feedback?

 

The Mk38 Gun Mount and Ballistics and Weapons Effectiveness Lessons from Pursuit of the Graf Spee, Part 1

hms-exeter-damaged-595x371

Photo: Heavy cruiser HMS Exeter seen after the battle, looking aft from the bow. Both forward twin 8″ gun turrets and the firecontrol system were disabled and the bridge destroyed by “splinters.”  

Introduction:

Note, this has been edited from the original, based on feedback particularly with regard to the ammunition remaining on Graf Spee after the engagement. I don’t believe the thrust of the post has been changed.  

This is the first of two parts. Part one will tell a story. Part two will talk about the implications of lessons learned, applied to how the Coast Guard might deal with the threat of terrorists using a medium to large merchant ship to make an attack.

These are themes that will be discussed in part 2 before looking at specific tactics to make the best use of what we have. Hopefully you will see these illustrated in the following story.

  • In comparing guns, at any given range, the longer ranged weapon generally enjoys an advantage in accuracy.
  • It is very difficult to sink a ship by gunfire alone.
  • Ships’ structure provide a degree of protection that makes it difficult to comprehensively target the crew of a ship without sinking the ship.
  • It is difficult to forcibly stop a ship with gunfire alone.
  • You can run out of ammunition before you accomplish your mission. The depth of your magazine may be important.

But first the story.

To the Germans, it is the story of a lone warrior, that by guile and deception, manages to evade the world’s largest navy for three months. Graf Spee is captained by an honorable and humane gentleman of the old school, Captain Hans Langsdorff, who after seeking a fight with the British and apparently besting them, does the unthinkable, retreating to a neutral port and sinking his own ship, but sparing the lives of his crew.

From the British perspective, it is a story of three little guys, lead by Captain (later Admiral) Henry Harwood, that work together, and despite severe damage, manage to corner a bully. Then by cleaver manipulation, the bully is convinced he has no chance of winning a second round and he self destructs rather than face the Royal Navy again.

Graf Spee Cruise, 1939

Graf Spee Cruise, 1939

The story I will tell is one of how many hits, how many rounds expended, how many rounds remained, and unlikely, almost invisible, but critical damage.

The British had made the Deutschland Class, of which the Graf Spee was the third and last, something of a boogeyman, bestowing on them the description “pocket battleships.” In fact they lacked the protection implicit in the battleship description. The Germans called them simply “Panzerschiff,” (armored ships) and in 1940 reclassified the surviving ships as heavy cruisers. Graf Spee was little better protected than the ships she would fight. She was in fact a large heavy cruiser, but there were others that were larger and better protected, including the German Hipper class (the first commissioned in 1939) and the American Baltimore and later cruiser classes (the first commissioned in 1943). The Japanese and Italians, who were also cheating on their treaty commitments, had several cruiser almost as large.

(Note: the distinction between heavy cruisers and light cruisers was one of gun caliber, not displacement. Light cruisers’ heaviest guns were 6.1″ (155 mm) or smaller. Heavy cruisers carried guns larger than 6.1″; usually 8″ (205mm) guns which were the largest cruiser guns allowed signatories of the Washington Naval Treaty.)

On the other hand, the guns of the Deutschland class were exceptional. These ships were a very real tactical problem for the British, since no single cruiser could deal with them individually. The British considered they needed 70 cruisers to meet their needs and they never approached that number. If they had to double up, there would be many needs left unfilled.

Admiral Graf Spee in the English Channel in April 1939. U.S. Naval Historical Center Photograph # NH 89566.

Admiral Graf Spee in the English Channel in April 1939. U.S. Naval Historical Center Photograph # NH 89566.

The Ships: 

  • Admiral Graf Spee, 16,200 tons (full load), 610 ft (186 meters) loa, six 11″, eight 5.9″, six 4.1″, eight torpedo tubes, 26 knots (reduced to 24 by a fouled bottom), crew 1,134.
  • HMS Exeter, (one of the smallest of the treaty heavy cruisers) 10,490 long tons (full load), 575 ft (175 meters) loa, six 8″ guns, four 4″, six torpedo tubes, 32 knots, crew 630.
  • HMS Ajax and HMNZS Achilles, 9,740 tons (full load), 555 ft (169 meters) loa, eight 6″ guns, four 4″, eight torpedo tubes, 32 knots, crew 570.

Note the total displacement of the three Commonwealth cruisers totaled 29,970 tons, almost twice the displacement of Graf Spee.

HMNZS Achilles,photo, State Library of Victoria - Allan C. Green collection of glass negatives.

HMNZS Achilles. Photo, State Library of Victoria – Allan C. Green collection of glass negatives.

The Guns:

Commonwealth:

  • British 8″/50 MkVIII (203mm), 256 lbs.(116.1 kg) projectile, 3-4 rounds/minute, range: 30,650 yards (28,030 m). Time of flight to 20,000 yards (18,290 m), 38.4 seconds, elevation for 20,000 yard range: 16.5 degrees
  • British 6″/50 BLMkXXIII (152mm), 112 lbs.(50.8 kg) projectile, 6-8 rounds/minute, range: 24,500 yards (22,400 m). Time of flight to 20,000 yards, 47.2 seconds, elevation 24.1 degreees.
  • British 4″/45 (102 mm), 31 lbs (14 kg), 10-15 rounds/minute, range: 16,300 yards (14,950 m)

German:

  • German 11.1″/52 (283mm), 661.4 lbs (300 kg) projectile, 2.5 rounds/minute, range: 39,890 yards (36,475 m) at 40 degrees elevation. Would have been more if 45 degrees elevation had been possible, elevation for 20,000 yard range: approximately 11 degrees.
  • German 5.9″/55 (149mm), 100 lbs. (45 kg) projectile, 6-8 rounds/minute,  range: 25,153 yards (23,000 m) at 40 degrees elevation, would have been slightly greater if 45 degree elevation had been possible.
  • German 4.1″/65 (105mm), 35 lbs (15.8 kg) projectile, 15 – 18 rounds/minute, range: 19,357 yards (17,700 m).at 45 degree elevation.

59-55_skc28_graf_spee_after_pic

Photo: After superstructure of Admiral Graf Spee showing 15 cm/55 and 10.5 cm/65 guns. Note the burned-out Arado Ar 196A-1 floatplane on the catapult and the after main-director rangefinder. Photograph taken at Montevideo, Uruguay in mid-December 1939, following the Battle of the River Plate. U.S. Naval Historical Center Photograph # NH 80976.

How Deep Is Your Magazine?:

The number of rounds carried by each ship would become important as the engagement progressed and as options were weighed. Total weight of rounds available was also an important variable determining how much damage could be inflicted:

Graf Spee: 322.6 tons

  • 11.1″: 720 rounds, 661 lbs each: 475,920 lbs or 238 tons.
  • 5.9″: probably 800 rounds, 100 lbs each, 80,000 lbs or 40 tons
  • 4.1″, probably 2550 rounds, 35 lbs each, 89,250 lbs or 44.6 tons

British: 296.25 tons:

Exeter: (86.05 tons)

  • 8″: 600 rounds, 256 lbs each: 153,600 lbs or 76.8 tons
  • 4″  600 rounds, 31 lbs each, 18,500 lbs or 9.25 tons

Ajax & Achilles (210.2 tons)

  • 6″: 3200 rounds, 112 lbs each: 358,400 lbs or 179.2 tons
  • 4″, 2000 rounds, 31 lbs each, 62,000 lbs or 31 tons
From official British report into the cruise of the Graf Spee and Battle of the River Plate. Published by HMSO (His Majesty's Stationery Office).

From official British report into the cruise of the Graf Spee and Battle of the River Plate. Published by HMSO (His Majesty’s Stationery Office).

Battle Before Breakfast:

It is 13 December 1939. In the Southern Hemisphere, this is one of the longest days of the year. As the sun comes up, Graf Spee sights masts on the horizon. Believing the ships to be a cruiser and two destroyers escorting a convoy she had hoped to attack, she turns toward them and accelerates.

6:10: Graf Spee’s increased speed results in more smoke and she in turn is seen by Commodore Harwood’s cruisers. In accordance with their previously planned response, the cruisers divide up, so that Graf Spee will have two separate groups to engage about 90 degrees apart. Heavy cruiser Exeter goes NW and the two light cruisers go NE. Additionally this should allow the two groups to spot fall of shot and provide range correction for each other.

06:18 Graf Spee opens fire at a little less than 20,000 yards. Exeter at 06:20, Achilles at 06:21 and Ajax at 06:23.

From the first, Graf Spee’s fire, targeting Exeter, is accurate. First salvo over, second salvo short, third salvo straddled. A near miss, bursting short, kills the crew on the starboard torpedo tubes and damages Exeter’s two spotter planes, which are jettisoned. It is textbook gunnery, the rocking ladder. Only one salvo of three is expected to yield any hits. Even then, dispersion of the rounds means, even if the fire control solution is perfect, it is unlikely more than one round out of a salvo would hit. Straddles that include no hits are common. So under ideal condition, if everything worked perfectly, the best one could expect would be that, one round of 18 would hit.

But the adversary is also doing everything he can to throw off the gunnery solution. Assuming the gun line is perpendicular to the base course, at 30 knots, a 30 degree course change for only thirty seconds will change the range 250 yards. At long range, this can be done between the time the guns fire and the shells impact. Both sides used smoke and evasive maneuvers to complicate the fire control problem.

At 06:26, Graf Spee scores a direct hit on the “B” turret (second turret on the bow). Splinters wipe out the entire bridge crew with the exception of the Captain and two others. The Captain is wounded but continues to command the ship. For the rest of the action, the ship is controlled by messenger to after steering.

06:37 Ajax launches her spotter plane to observe and provide correction of the cruisers’ gunnery.

06:38 Exeter is hit twice. One hitting the “A” (most forward) turret and putting it out of action, the other strikes the hull starting a fire.

“At this point, Exeter was severely damaged, having only “Y” turret still in action under ‘local’ control, with Jennings (Gunnery Officer–Chuck) on the roof shouting instructions to those inside. She also had a 7° list, was being flooded and being steered with the use of her small boat’s compass. However, Exeter dealt the decisive blow; one of her 8 in (200 mm) shells had penetrated two decks before exploding in Graf Spee′s funnel area, destroying her raw fuel processing system and leaving her with just 16 hours fuel, insufficient to allow her to return home.

“At this point, nearly one hour after the battle started, Graf Spee was doomed; she could not make fuel system repairs of this complexity under fire. Two-thirds of her anti-aircraft guns (two out of three mounts–Chuck) were knocked out, as well as one of her secondary turrets (one of eight guns–Chuck).

06:40 A near miss on Achilles–splinters kill four, wound several others, and temporarily disable the main fire control director.

07:25 An 11″ shell puts one of Ajax’s after turrets out of action and jams the other. She now has use of only half of her 6″ battery.

07:30 Flooding shorts out power to Exeter’s only remaining turret.

About this time, it appears Graf Spee begins to break off the engagement and heads for the River Plate.

07:40 Now listing heavily, with all major guns disabled and her speed reduced due to flooding in the bow, Exeter breaks off action and begins a long retirement to the Falklands where she will make temporary repairs before returning to Britain for a 13 month refit.

About the same time the Exeter turns to disengage and begin her transit to the Falkland, Commodore Harwood, having closed to close to 8,000 yards, hears reports he is running short of ammunition. He probably also realizes he is in a very dangerous position where his adversary’s shooting is much more accurate. He changes tactics, opens the range and plans to make a night attack when an effective torpedo attack is more likely.

Ajax and Achilles drop back and follow Graf Spee as it becomes obvious she is heading for the mouth of the River Plate. Some shots are exchanged, but these appear to be only Graf Spee warning the cruisers to maintain their distance.

Late in the evening Graf Spee anchors in Montevideo harbor.

The following day she releases her 62 merchant navy prisoners, transfers wounded to hospitals ashore, and buries her dead.

How accurate were they?:

The British light cruisers fired 2064 x 6″ projectiles and scored 17 hits or one hit for every 121 rounds fired or 0.82%. Of their original 3200 rounds 1136, 35.5%, remained.

Exeter fired 193 x 8″ rounds (possibly a few more) and scored three hits or one hit for every 64 rounds fired, 1.55%. This is all the more remarkable because 177 of these are fired by the after twin turret, most of which were fired under local control, and Exeter never closed the range to the degree the light cruisers did. It appears one of Exeter’s three hits was made while the gun was in local control.

Graf Spee fired 414 x 11.1″ rounds. Graf Spee’s 11.1″ hit Exeter at least seven times plus a particularly damaging near miss, along with several others that caused minor damage. These guns also made two hits on Ajax and a damaging near miss on Achilles. If we assume ten hits, that is one hit for every 41 rounds fired or  2.4%. Graf Spee had only 306 rounds, 42.5%, remaining. If she continued shooting with the same degree of accuracy, these could be expected to score at best eight more hits.

My primary source indicates that Graf Spee’s relatively powerful secondary armament fired 377 x 5.9″ and 80 4.1″ projectiles, but made not hits. They should have performed similarly to the British 6″. “It was not known until later that splinter damage to the director directing the 15 cm fire caused bearing track inaccuracy for the 15 cm fire…a small shell splinter entered the starboard director (of assume the forward conning tower FC station). But as luck would have it, the optic was left intact and the director function but little impaired, so the damage remained unknown until late in the evening. The casualty was not noticed by the operator during the battle at all. However, the director did not provide the proper fine bearing angle alignment to the battery, resulting in very poor on target performance.”

A Second Round?:

Diplomatic rankling begins almost as soon as Graf Spee anchors, with the Germans asking for two weeks in port to make the ship seaworthy enough to deal with the North Atlantic winter. The British first try to have Graf Spee’s stay limited to 24 hours, and then, realizing it will be several days before their heavy units arrive, they attempt to keep her in port without saying so.

The Uraguian authorities are unmoved and give the Graf Spee 72 hours.

Meanwhile the Royal Navy has ordered a battlecruiser, an aircraft carrier, and eight cruisers to converge on the River Plate to make sure Graf Spee does not escape.

22:00, 14 December, Heavy cruiser HMS Cumberland arrives, having steamed at full speed for 36 hours from the Falkland Islands. 28% Larger than Exeter (13,450 tons full load and 630 ft loa), with 33% more 8″ guns, she brings with her full magazines, 800 rounds of 8″.

17 December, Graf Spee sets sail, but a large portion of her crew has already left the ship. She stops, anchors, the rest of the crew leave the ship, transferring to waiting tugs. A series of explosions erupt and Graf Spee settles in shallow water, her guns and superstructure still out of the water.

Why did they do it?:

The British provided disinformation that the battlecruiser Renown and aircraft carrier Ark Royal were waiting outside and the Graf Spee crew members convinced themselves they saw the masts of these ships offshore.

Even an accurate view of the odds looked unfavorable for a successful sortie. After the arrival of HMS Cumberland, Graf Spee faced a force at least as powerful as the one engaged on the 13th. Additionally, the three cruisers waiting off shore did not have to sink Graf Spee to be successful. All they really had to do was shadow her until the heavy units could join them and Graf Spee’s fate would be sealed. With less than three quarters the ammunition she had used in the first engagement and her forward fire control director already disabled, Graf Spee’s chances of inflicting significant damage, escaping her tormentors in the South Atlantic, getting through the British blockade of Germany, and making it home appeared slim.

Then there is the matter of the fuel oil purifier. Without it, they could not expect to make it back to Germany, even if the Royal Navy were not in their way.

_________

Annex. Extracts from H. M Ships Damaged or Sunk By Enemy Action, 3 Sept 1939 to 2 Sept. 1945

EXETER during the “Battle of the River Plate”, came under shell fire from the German Pocket Battleship, ADMIRAL GRAF SPEE.

Hit No. l, struck the shelter deck just abaft “B” Turret and passed out through the superstructure side without exploding.

Hit No. 2, struck the front plate of “B’ Turret between the two guns and detonated on impact. “B” Turret was seriously damaged and put out of actions. Splinters caused damage and casualties on the bridge.

Hit No. 3,, struck on or very near, the fluke of the starboard sheet anchor and detonated on impact. The side plating was split and torn and much damage in the paint shop was caused by splinters.

Hit No. 4, struck the forecastle deck on the middle line just aft of the cable holders and exploded on impact. A hole 10 ft. by 10 ft. was blown in the forecastle deck and splinters penetrated the upper deck.

Hit No. 5, struck the jacket of the right gun of “A” Turret, and exploded on impact. “A” Turret was put out of action although it was found later that the turret could be trained and the left gun used. The forecastle deck was torn and the upper deck damaged by splinters.

Hit No. 6, passed through the whee!house, charthouse, out through the armament office and exploded just forward of the starboard 4 inch H.A. (High Angle-Chuck) Gun. Damage from splinters was widespread, ammunition in R.U. (Ready Use-Chuck) lockers was ignited, the lower bridge and 25% of the 4 inch armament was put out of action.

Hit No. 7, passed through the ship’s side just under the upper deck abreast “B” turret, travelled aft through the mess spaces on the lower deck and exploded abreast the E.R.A .’s (Engine Room Artificers-Chuck) mess. Damage from splinters was widespread, the fire main was fractured, communications seriously damaged and the lower deck holed. The 4 inch H.A. magazine and handing room were flooded by water escaping from the fractured fire main. Fire broke out in the mess spaces just aft of “B” turret supports.

Splinter Damage. EXETER suffered a great deal of superficial damage from splinters due to shells that burst short. Splinters on the ship’s side near the waterline caused a good deal of flooding. Most aerials were carried away and searchlights, signal projectors;, rigging etc. were badly damaged. One R.U. Ammunition locker was also ignited by splinters.

Fighting Efficiency = Seriously impaired. “A”, “B” and °Y° Turrets and 25% of the 4 inch H.A. armament was out of action. Slight loss of speed due to flooding and consequent heel and trim of the ship.

AJAX during the “Battle of the River Plate” came under shell fire from the German pocket battleship ADMIRAL GRAF SPEE. The direct hit struck the after superstructure port side passed thro’ “X” barbette and exploded in the Admiral’s cabin, starboard side causing slight structural damage. The shell did not detonate but burst with a mild explosion. Splinter damage caused, “Y” turret to jam.

(Ajax was again hit by a 283 mm (11.1 in) shell that destroyed her mast and caused more casualties, but damage was apparently not worth reporting–Chuck)

Fighting Efficiency = Impaired, “X” and “Y” turret were out of action due to the shell hit. “B” turret had one gun out of action due to failure of the hoist.

ACHILLES during the “Battle of the River Plate” came under shell fire from the German pocket battleship ADMIRAL GRAF SPEE. Splinters from shells bursting short pierced the ship’s side above the waterline, bridge screen etc, and also caused other slight damage. Minor damage was sustained in the director control tower but after casualties had been replaced it was able to continue in action.

Fighting Efficiency – Not impaired. Gun fire was not efficient until casualties in the D. C.T. (Fire Control Director–Chuck) were replaced. W/T (radio-Chuck) was out of action temporarily.

REMARKS The “Battle of the River Plate” revealed the following items.

  1. Increased protection to vital communications required.
  2. Additional portable telephones required,
  3. Improvement to look-out positions necessary,
  4. Need for increased protection for exposed personnel.
  5. Remote control of the smoke apparatus required.
  6. Square ports to be abolished.
  7. Automatic emergency secondary lighting to be introduced.
  8. Modifications required to telephone hand sets to prevent “jumping off”.
  9. Additional portable pumps to be supplied.
  10. Fire mains to be modified to provide for easier isolation and repair.

Print Sources:

  • Bennett, Geoffrey, Battle of the River Plate, Ian Allen, Ltd., 1972
  • Campbell, John, Naval Weapons of World War Two,  Conway Maritime Press Ltd, 1985
  • Chesneau, Roger, Conway’s All the World’s Fighting ships, 1922-1946, Conway Maritime Press Ltd, 1980

On Line Sources:

Don’t Go Out Without Protection

U.S. Coast Guardsmen, assigned to Port Security Unit 309 in Port Clinton, Ohio, conduct security patrols during exercise Combined Joint Logistics Over-the-Shore (CJLOTS) 2015, at Anmyeon Beach, Republic of Korea, June 30. CJLOTS 2015 is an exercise designed to train U.S. and ROK service members to accomplish vital logistical measures in a strategic area while strengthening communication and cooperation in the U.S.-ROK alliance. (U.S. Navy photo by Mass Communication Specialist 1st Class Kori Melvin/Released)Photo: TPSB with ballistic protection,  Anmyeon Beach, Republic of Korea, June 30. Exercise CJLOTS 2015 (U.S. Navy photo by Mass Communication Specialist 1st Class Kori Melvin/Released)

Got an interesting link from Luke S. “Evaluation of Composite Armor for Coast Guard Vessels” (pdf) is a study from 1989, looking at how selected portions of the 110 foot WPBs might be protected from small arms fire. Here is the summary of their findings.

Up to a firing range of 100 yards, which was the limit of this study, personnel inside Island Class cutters are vulnerable to lethal rifle fire coming from drug smugglers. Test results showed that unconditional protection for personnel inside can be obtained by adding KRP (KEVLAR reinforced plastic–Chuck) armor panels to the cutter. This is also a more weight effective solution than increasing the thickness of the hull and superstructure. Although it was found that placing the KRP either in front of or behind the 1/8″ aluminum was equally effective, it should be noted that the aluminum by itself was overmatched by the threats. In general, it is more efficieut to place the KRP behind metal.

The USCG R&D Center defined three areas of the Island Class cuttfer that required protection in order to allow it to continue its mission if it came ander fire. These were the bridge and the communications room, both behind 1/8″ aluminum, and the magazine behind 5# steel. A visit was made to the USCGC Matinicus to take measurements and assess the feasibility of retrofitting KRP armor in those areas. Retrofitting them inside the bridge and communications room could be done by placing them in the space between the exterior aluminum skin and the interior trim panels. This might require some fit and trim but KRP panels can be cut and drilled so there should be no particular difficulty. Another option is to place the panels on the exterior of the bridge and communications room. This would appear to be an easier task but would present a different set of considerations. Since the KRP panels would have to be spaced 3″ in front of the aluminum, the panel supports would have to be designed to withstand green water loading. Environmental effects on these panels caused by exposure to seawater and UV radiation is not a problem for adequately sealed KRP. For the remaining area requiring armor, the magazine, mounting the panels against the steel hull inside the vessel did not appear to be difficult.

The amount of material and weight added in each of the critical areas is summarized in TABLE 6 for the worst case threat, the 7.62mm, M80 at point blank range.

TABLE 6 included the location to be protected, the total area to be armored, the weight per square foot for the armor, and the total weight for protection to that level. I have summarize the data below, but did not include the weight per sq.

  • Bridge 33′ x 4′ – 132 sq ft, 1056 lbs.
  • Communication rm. 14′ x 6′ • 84 sq ft, 672 lbs.
  • Magazine 6. x 6′ 36 sq ft, 180 lbs.
  • Total area covered: 252 sq. ft. weight: 1908 lbs.

These numbers are guidelines because the minimum armor density required was not determined in this study. Nevertheless, realizing these numbers are on the high side, the material cost from a commercial panel manufacturer for a KRP panel weighing 8 psf (lbs/sq ft–Chuck) with 20% resin would be about $40,000. This is basd upon a panel cost in the $20 to $24 per pound range.

Makes me wonder if anything was done about this, particularly for the WPBs based in Bahrain. Also, was anything included in the Webber class WPCs?

Even this relatively light armor would also provide a degree of protection against heavier .50 cal. and 14.5mm machine guns if fired from a greater range and/or if the round strikes at an oblique angle.

In addition to the bridge, comm space, and magazine, the gunners on open mounts could also use some protection as I’ve suggested before.

I have heard that ballistic protection for the Offshore Patrol Cutter has been deleted. This may be a mistake, particularly if it is as inexpensive as it appears.

Late addition:

Just found this. The photo below is Prince Charles boarding the HMS Middleton (a 32 year old, 750 ton mine countermeasures vessel) in Bahrain. The post is interesting regarding the situation in Bahrain, but I wanted to mention the gun crew protection visible between the stack and mast. The gun is an M134 “mini-gun,” a six barrel 7.62mm “gatling” gun. The additional pretection is apparent. Apparently the Brits recognize the need to protect their gun crews. It is not just about protecting the gunner, it is also about keeping the gun that is defending the ship operational.

hmsmiddletonm34

Sea Shepherd’s New Vessel “Ocean Warrior”

gCaptain reports the Sea Shepherd organization has taken possession of their new vessel “Ocean Warrior.” The little ship could make a credible patrol boat, and the bridge layout is also interesting.

Background here.

Characteristics: 

Reportedly this vessel is based on an existing design. Here you can find a product description of the “parent craft,” the here: Download ›

Based on the parent craft, it appears the dimensions are:

  • Length O.A. 53.25 m (175 feet)
  • Beam O.A. 10.10 m (33 feet)
  • Depth at sides: 4.70 m (15.4 feet)
  • Draught: 3.20 m (10.5 feet)
  • Speed: 30 knots
  • Four engines totalling 8 megawatts or approx 10,728.2 HP

They claim an exceptional range of “3100 nm. at max. speed” but they also list a range of maximum speed from 20-30 knots depending upon choice of engines, so I assume this is really 3,100 miles at 20 knots, but that is still exceptional and probably would translate to over 5,000 miles at most economical speed.

There is a “virtual tour’ of the parent craft here.

Comments: 

I would note that all four engines and all the generators are located in a single compartment (good for minimal manning/not so good for damage control) and the small helo deck on the “Ocean Warrior” has a number of obstructions that would be unacceptable to the Coast Guard, but it could make a good UAV operating area.

Crew for the parent craft is only eight, and consequently only birthing for eight is provided on the parent craft, but it also includes airline style seating for 80 in the main deck compartment at the foc’sle. Presumably on the Ocean Warrior this area has been converted for additional birthing.

UAV for WPC Sized Vessels

Photo: Information systems technicians conduct pre-flight checks on a Puma unmanned aerial vehicle (UAV) aboard the coastal patrol ship USS Monsoon (PC 4). Photo: US Navy

NavalToday reports, the Navy has been testing a UAV, RQ-20A Puma AE (all environment), on the USS Monsoon, a patrol craft of the same size as the Coast Guard’s Webber class WPCs.

“Weighing approximately 14 pounds, the small unmanned aerial vehicle (UAV) can provide more than three hours of flight time with a range of 15 kilometers and operating altitude of 500 feet. Equipped with an electro-optical and an infrared camera, the Puma can be manually operated or by GPS.”

“… Puma is most commonly employed as a precursor search and overwatch platform to support her VBSS team…”

 

 

New South Korean Patrol Craft

According to the local news agency Yonhap, South Korea's Navy launched a new fast patrol boat to help counter North Korea's hovercraft force along its maritime demarcation line, the military said Thursday July 28, 2016.
An artist rendering of South Korea’s new Chamsuri-211 fast patrol boat
(Credit: Yonhap)

NavyRecognition is reporting the South Korean Navy will be getting the first of a new class of Patrol Craft in late 2017. It is a bit smaller than the Webber class at 44 meters in length and 210 tons. It is designed specifically to counter North Korean Hovercraft. It is armed with a 76 mm gun and a pair of remotely operated, radar controlled 12.7mm (.50 cal.) machine guns. The unusual weapon seen on the stern is a launcher for 130mm (5.1″) guided rockets (apparently twelve) . (I suspect these are actually guided versions of the 5″ Zuni rocket, much like the APKWS is a guided version of the Hydra rocket. )

The vessels is expected to have a max speed of about 40 knot and will apparently be powered by waterjets. I don’t see any boat on the artist impression above.

87 Footer Patrols SE Alaska

There is an interesting news release by the 13th District reporting, in part:

“The crew of the Cutter Terrapin completed a 37-day patrol to Southeast Alaska during which they protected living marine resources, safeguarded lives at sea and enhanced maritime security across the region.

“The crew of the Terrapin supplemented Coast Guard Sector Juneau’s response cutter requirements during the transition period between the homeport shifts of the 110-foot Patrol Boats Naushon and Chandeleur and the 2017 arrival of new Fast Response Cutters, the John McCormick and the Bailey Barco.”

Nice to see that they will be getting Webber class WPCs relatively soon. We knew they were coming. Should be an notable improvement over the 110s that were always a bit too thin skinned to operate freely up there.