While the number of nudear submarines facing the West has dedined, the number of diesel threats has remained steady, and more and more third-world countries are acquiring first-line subs from Russia, Gerrnany, or Sweden.

Combine this with the shift from "blue water" to coastal operations and the West's problem is compounded. Training for over a decade in the relatively acoustically simple deep water environment, ASW forces now have to deal with shallow water, high ambient noise, variable salinity near river mouths, and the possibility of operating near a hostile shore.

To illustrate the problem, here is a scenario generator that creates encounters between late-model diesel submarincs and different surface ASW groups.

Operational Situation: The government of A has extended claim to territorial waters from 12 nm to 100 nm. The B government, determined to preserve its right of free passage, is conducting another of its "Freedom of the Seas" exercises, deliberately steaming into areas it considers international waters but are claimed by A.

Environment: Roll time of day and weather randomly, although country B will delay the exercise if the sea state is six or greater. The scenario takes place on the continental shelf, within l00 nm of the coast. Subtract 3 from the D10 roll for sonar conditions. Water depth in the patrol area varies from shallow to Intermediate II (see Setup). Convergence zones are not present in such shallow water.

Tactical Situation: The B surface group has entered waters claimed by A. Although normally these exercises have not been opposed, A's brand-new diesel submarine has been assigned to patrol the area, with orders to sink any intruders.

A: India, Iran, Pakistan

B: The United States, The United Kingdom, Russia

A's Orders: Defend your patrol area. Sink any contact classified as not friendly. Neutrals have been warned to keep clear.

A's Forces:

India: One Shishumar (Type 209/1500) SS
Iran: One Russian Project 877 [Kilo] SS
Pakistan: One Agosta 90B SS

A's Victory Conditions:
Decisive: Sub sinks a warship and remains undamaged.
Tactical: Sub damages a warship over 50% and remains undamaged.

B's Orders: Steam through the exercise area, approaching to within 20 nm of shore, but remaining at least 15 nm away (12 nm limit plus 3 nm margin). You must enter the area from the eastem or western edge and leave by the opposite side.

B's forces:

USA: One Arleigh Burke Flight IIA DDG and one O.H. Perry FFG
UK: One Type 42C DDG, one Type 23 FF
Russia: One Udaloy DD, one Krivak II FF.

All ships have wartime allotments of aircraft.

B's Victory Conditions:
Decisive: Force passes through the area undamaged.
Tactical: Force passes through the area with both ships afloat and under power (speed >0), and sub is sunk.

Setup: The Referee should draw a random shoreline at least 50 nm long. The exercise area is a box 50 nm long extending 50 nm out from shore. A's player is aware of its exact location because B has posted the area (as required by International Law) in Notices to Airmen and Mariners, in other words a public decdaration of their right of free passage. Within D6 nm of the shore the water depth will be 25 meters or kss, too shallow for sub operations.

Within D6 nm of this boundary, water depth will be Shallow (26 - 50 meters). D6 nm out from this, the depth becomes Intemmediate I (51 - 100 m), and D6 nm further out, it becomes Intermediate II (101 - 200 m).

Allow the sub player to plot his patrol route, including depth and speeds and weapons status. Have B's player plot his route through the zone, including speeds and sensor status. The referee can then plot the two sides' movement at 30-minute or 3-minute intervals and see where they interact.

Agosta 90B

Displacement: 1760 subm
Acoustic Counterm: 3rd Gen
Electronic Counterm: None
Propulsion: Diesel-Electric
Size Class: Small
Max Depth: Int V
In class: 0+0+3
In Service: 1999
ESM/AIR: 3rd/3rd Gen
Crew: 36
Signature: Small/V Quiet
Btry Rtng: 100
Weapons: PB&SB(5)2 533mm TT w/16 F17P Mod 2 and SM39 Exocet (F,D France)
Sensors: DRUA 33 (J France) and Advanced Eledone suite (M France)

Remarks:
Sonar suite indudes TSM 2253 passive flank array and the DUUX 5 Fenelon passive ranging array. Endurance 60 days. Integrated Digital FCS. Third unit (IOC 2006+) will have AIP propulsion. Hull is HY100-equivalent steel.

Damage and Speed Breakdown:

Dam Pts:	0	8	17	25	30	34
Surf Speed:	12	8	6	3	0	Sinks
Subm Speed:	20	15	10	5	0	Sinks

BT