Harpoon: The Hawaiian Trough 1997

Harpoon
South China Sea 1997

USS Galveston, Third Fleet

The political situation in the South China Sea has been deteriorating.  A US flagged oil exploration ship has been seized by the Chinese PLA, and a task force built around the USS Independence  has engaged and sunk a Han class submarine that fired on the carrier.

Mission 1
Passage: Ballast Point, San Diego
to Pearl Harbour, Honolulu.

INT MESSAGE 3rd Fleet HQ

To: Captain USS Galveston,

A Canadian P-3 Orion operating on a training mission out of San Diego thinks that they may have picked up a submarine 237 miles southwest of Galveston's current position. They even got positive MAD (magnetic anomaly detection) contact, but lost contact after tracking the submarine for about twenty minutes. The P-3 crew is pretty confident that what they found was an SSN.  Naval Intelligence thinks it may even be one of the Chinese Han class of nuclear attack submarines.

Proceed with caution.  Strictly do not engage hostiles unless in self defence.

SSN 671 USS Galveston.   

4× 21 in (533 mm) torpedo tubes, 37× Mk 48 torpedo, Tomahawk land attack missile, Harpoon anti–ship missile, Mk 67 mobile, or Mk 60 Captor mines (FLTII and 688i FLTIII have a 12-tube VLS)

Max Depth 300 metres

Full Speed 32 Knots, Flank Speed 35 Knots.

133 crew.

For this transit, USS Galveston has been given only 12 Mk 48 ADCAP torpedoes.  With a top speed of over fifty knots while running deep, and a range in excess of 30,000 yards, the Mk 48 ADCAP is arguably the best heavy torpedo in existence.  Its only real competition coming from the British Spearfish, carried by the submarines of the Royal Navy.

Game Setup

Galveston is running at 25 knots on a course of 310 degrees towards Pearl Harbour, depth Intermediate (4), with some cavitation due to speed.  The TB-23 towed-array sonar is deployed.  Sea Depth 5000 metres (over the Hawaiian Trough)

Speed	Depth	Sonar	Firing	Command	Targeting
Flank 40kn	1  Surfaced	Active Pinging	Mk 60 Captor mines	Capt	FIRE One to Four
30kn	2  Periscope	Single Ping	VLS Tomahawk Land targets	1st Officer	Firing Solution
20kn	3  Shallow	TB-23 array	VLS Harpoon Anti-ship	OOD	Second Bearing
10kn	4  Inter	TB-16 array	21" Tube Mk 48 ADCAP	Weapons	First Bearing
All Stop	5  Deep	Internal Passive	Opened Outer  Doors	Ch.Engineer	Scope Up
Spin reverse	6  Very Deep	Closed	Closed Outer  Doors	Chief	Scope down

Turns
Intermediate Turn (10 minutes)	Tactical Turn (1 minute)
Plotting Phase	Plotting Phase	Log Movement, Firing, other orders
Movement Phase	Movement Phase	Move either 10 mins (Inter)or 1 min (Tct)
	Planned Firing Phase	Plotted fire exchanged Simultaneously
Detection check Phase	Detection check Phase	Visual, Radar, Sonar, ESM.
	Air movement Phase	Air Move and Fire
	Reaction Fire Phase	Shipboard at New Targets (half max)
	Resolution Phase	Resolve all weapons fire or movement

Turn #1 Intermediate 17th October 0130hrs

Plotting  

Make the turn to 310 degrees

Movement

25 knots  4.1" on table

Detection

Passive Sonar reports “Tonal contact, center bearing 253 on the end-fire beam,” 

The contact is designated "Master 1"

“Blade rate indicates Master 1’s speed is steady at eighteen knots, identifies as Han#239”

Turn 2 (Intermediate) 0140hrs

Plotting 

“Man battle stations torpedo, reduce 10 Knots.”  

Movement

10 knots  1.6" on table

Detection

“Master 1 now bearing 169, BSY-1 range is 12,000 yards. He is not in a convergence zone.  Confirmed as Han#239”

Turn 3 (Tactical) 0141hrs

Plotting Phase

“Torpedo room, fire control, make tubes one and two ready in all respects and open the outer doors. Waiting on Firing solution."

Movement Phase

10 knots 0.16"

Planned Firing Phase
Galveston's orders are clear.  She must only fire to defend herself.

Detection Check Phase
Active Pinging from Master #1.  Firing solution bearing 169, 12000 yards

Air movement Phase

Reaction Fire Phase

Resolution Phase

Turn 4 (Tactical) 0142hrs

Plotting Phase

“Lock Firing solution. now bearing 163"

Movement Phase

10 knots 0.16"

Planned Firing Phase

Galveston's orders are clear.  She must only fire to defend herself.

Detection Check Phase

Torpedo in the water! Type SET-53, bearing 163.

Air movement Phase

Reaction Fire Phase

Resolution Phase

Turn 5 (Tactical) 0143hrs

Plotting Phase

“Firing solution locked. now bearing 163"

Movement Phase

10 knots 0.16"

Planned Firing Phase
Galveston's orders are clear.  She must only fire to defend herself.

Detection Check Phase
Torpedo from Master #1 goes active. bearing 163.

Air movement Phase

Reaction Fire Phase

Resolution Phase

Turn 6 (Tactical) 0144hrs

Plotting Phase

“Lock Firing solution. now bearing 162  Turn 162, all stop.  Match sonar bearings and shoot, tubes one and two,

Movement Phase

Turn to 162 all stop

Planned Firing Phase
Firing two Mk 48 ADCAP torpedoes.  Ten remain.

Detection Check Phase
“Both torpedoes have acquired Master 1,  Enemy Torpedo Type SET-53, bearing 163, remains active.

Air movement Phase

Reaction Fire Phase

Resolution Phase

Han torpedo runs down at 6000 yards. That;s Russian technology for you, its supposed to do 12000.

Turn 7 (Tactical) 0145hrs

Plotting Phase

“Cut the wires, shut the outer doors, and reload tubes one and two,
Evasive action, launch two ADC Mk 2 decoys”  Spin the screw to Flank speed.  Come to heading 50 degrees.
Movement Phase

Increasing speed beyond 10 knots Heading 50 degrees

Planned Firing Phase
Two ADC Mk 2 decoys.

Detection Check Phase
“Both torpedoes locked Master 1, closing fast.

Air movement Phase

Reaction Fire Phase

Resolution Phase

Explosions in the water  bearing 160 degrees.

Master #1 is destroyed.

Turn 8 (Intermediate) 0155hrs

Plotting 

Secure from battle stations.  Reduce 25 Knots. Come to 340 degrees for Pearl Harbour.  

Movement

25 knots, Turning 340 degrees 

Detection

Master #1 breaking up

The board is clear.  

A win for USS Galveston who totally outclassed her opponent.

Let's see how she copes with stronger opposition...