Under normal circumstances, the decision on whether to sortie or remain in port is largely based on the answer to a single question: Would the vessel in question be better off attempting an evasion at sea or remaining in port? Evasion rationale should include consideration of the following general factors:

* Vessel characteristics
* Berth and anchorage conditions
* Most recent tropical cyclone warning advisory
* Tropical cyclone climatology
* Sheltering or haven qualities

Individual vessel characteristics and berth/anchorage conditions are best determined by those responsible for each vessel and local port authorities. Tropical cyclone warnings are issued by the Naval Pacific Meteorology and Oceanography Center/Joint Typhoon Warning Center Pearl Harbor for Department of Defense assets.

Per COMNAVFORKOREAINST 3140.1, Commander Naval Forces Korea, working with the Naval Pacific Meteorology Center/Joint Typhoon Warning Center Pearl Harbor and USFK will direct the setting of appropriate Conditions of Readiness (CORs) for the CNFK AOR. Messages which contain CORs contain forecasts of maximum winds expected. CORs will be ordered for specific areas such as Area IV Commander Fleet Activities Chinhae as the storm warrants. Local Commanders may order a higher COR at their discretion and will report attainment and termination of each COR placed in effect. CNFK will direct the securing of appropriate CORs for the CNFK AOR.

Tropical Cyclone Conditions of Readiness (TCCOR):
* TCCOR 4 - Destructive winds (sustained winds exceeding 33 kt) are possible within 72 hours.
* TCCOR 3 - Destructive winds are possible within 48 hours.
* TCCOR 2 - Destructive winds are anticipated within 24 hours.
* TCCOR 1- Destructive winds are anticipated within 12 hours.
* TCCOR 1 Caution - Winds 0f 34-49 kt are occurring at a particular installation.
* TCCOR 1 Emergency - Destructive winds are occurring at a particular installation.

* TCCOR Recovery - Used by TCCOR Authority to designate a period of time after the passage of a typhoon when work and survey crews are sent to determine the extent of damage and to establish safe zones around hazards (downed power line, unstable structures, etc.). Until the recovery process is declared completed and either ALL CLEAR or STORM WATCH has been declared by the installation TCCOR Authority, general base population will be asked to remain indoors.
* TCCOR STORM WATCH - Although the destructive winds have subsided, or are currently not forecasted to occur, there is still the possibility of danger due to the proximity of the storm and due to unforecasted changes in storm track and/or strength. Personnel should stay alert, and continue to monitor television and radio announcement. A rapid change to TCCOR conditions to occur.
* TCCOR ALL CLEAR - The storm is over and not forecast to return (may be declared by installation Commanders).

A Broadcasting Service of the Korean Maritime Safety Information (weather, search and rescue, navigational warnings, etc.) is offered at regular times for all vessels navigating along the coastal sea of the Korean Peninsula. This service uses two frequencies from transmitting stations at Jukbyeon (37°03'N 129°26'E) and Byeonsan (35°36'N 126°29'E) for seas east and west of the Korean coastline, respectively. Transmissions cover a range of 200 nmi from each station. English is broadcast on 518 kHz (International Common Frequency) and Korean on 490 kHz. The broadcasting times for English are 0330, 0730, 1130, 1530, 1930, and 2330 UTC. All navigators can receive this information automatically by using a NAVTEX receiver on board.

Long range navigational warnings (NAVAREA navigational warnings) are promulgated according to the World Wide Navigational Warnings Service (WWNWS) System by cooperation between the IHO (International Hydrographic Organization) and the IMO (International Maritime Organization). For Korea broadcasts are made in English and Korean from the following locations:

Jeju-Call Sign HLE, 2,299 kHz, 0902 and 1702 UTC
Gangneung, Call Sign HLK, 2,836 kHz, 0903 UTC
Gunsan, Call Sign HLN, 2,507 kHz, 0403 UTC
Incheon, Call Sign HLC, 2,284, 0003

The Port of Pusan is not considered a typhoon haven. An early sortie is recommended for all ships to proceed completely out of the Port. All of the anchorages may be impacted by strong winds and heavy seas.

The interpretation of tropical cyclone climatology is addressed in the following sections.

Evasion at Sea

Evasion from Port of Pusan is the recommended course of action for all U. S. Navy ships.

Per COMNAVFORKOREAINST 3140.1, Commander U.S. Naval Forces Korea as Senior Officer Present Afloat (SOPA) is responsible for preparing and issuing sortie instructions and orders for all ports in Korea. Any Commander may order emergency sortie for units under his operational control. When issuing sortie orders, Commanders shall keep COMSEVENTHFLT, SOPA, and Immediate Superior in Command (ISIC) informed. Additionally commanding officers of individual units should not hesitate to request permission from the SOPA or ISIC to get underway prior to a sortie. Responsibility for the safety of the ship/unit remains squarely on the CO's shoulders, as no other understands the strength and weakness of that particular unit.

For evasion at sea, steaming into the Yellow Sea or the Sea of Japan are the open ocean sortie options available. The choice will depend on the strength and forecast track of the approaching storm and how early in the planning process the sortie decision is made.

If evasion to the Sea of Japan is selected, the commander must be aware that the ship may be placed in the stronger, and therefore more dangerous, semicircle (the right side of the storm with respect to the storm's direction of movement). The following factors should also be considered:

(1) Lead time. Since tropical cyclones tend to increase their speed of movement after recurvature, planners must provide for an early departure in order to clear the area before the storm's circulation arrives. A storm movement in excess of 30 kt is not uncommon while the storm is still in the vicinity of the Tsushima (Korea) Strait, and may further accelerate when the storm reaches the Sea of Japan. The potentially rapid speed of the tropical cyclone may allow it to overtake evading ships unless the sortie is carefully planned and initiated early in the decision process.

(2) Other potential havens. The Port of Chinhae has typhoon haven qualities but should only be considered as a last resort in the event of a typhoon. The specific guidance provided in the Chinhae Port Study is as follows:

If a tropical cyclone is 2-3 days away from passing Chinhae and is forecast to be 50 kt or less in intensity at CPA, Chinhae (anchorage) would be an excellent haven.

If a tropical cyclone is 2-3 days away from passing Chinhae and is forecast to be of typhoon intensity (greater than or equal to 64 kt) at CPA, Chinhae should not be considered as a typhoon haven. This is particularly true if the storm is forecast to pass within 100 nmi west of Chinhae or 50 nmi east of Chinhae. Passage to the west of Chinhae (Typhoon Maemi) is the most dangerous situation.

If the evading unit(s) does not wish to sortie across the Sea of Japan, or if it appears that the storm may overtake the evading unit(s), commanders may wish to consider using the Port of Maizuru, Japan as a typhoon haven. Maizuru (35°29'N 135°23'E) is evaluated in the Japan Section of this manual.

Whichever option is chosen, ship captains should remember that tropical cyclones are historically unpredictable, especially in the recurvature phase. The 48-hour forecast position error may exceed 200 nmi. Consequently, the storm may be closer to or farther from Pusan than the forecast indicates, or be right or left of its forecast track.

The nearest typhoon haven is the Non-Tidal Basin in the Port of Inchon. This would be the safest location but the pilots indicated during the Inchon Site Visit in September 2008 that if there is a threat by a typhoon or bad weather, congestion will likely occur outside the Lock Gates with many ships trying to get into the Non-Tidal Basin. Note that ROKN deep-draft vessels did sortie to the Non-Tidal Basin during Typhoon Maemi.

Commanding officers and ship masters with access to tropical cyclone warnings and advisories coupled with OTSR services are most capable of making the safest and most prudent decision for successful storm evasion and avoidance. In all sortie situations, OTSR services from Naval Pacific Meteorology and Oceanography Center (NPMOC), Pearl Harbor should be requested and utilized. The best sortie route in a specific tropical cyclone scenario is largely dependent on the location of the tropical cyclone and the forecast track. During any tropical cyclone threat there is normally one to three options available to the commanding officer and ship master. Selection of the best option is the objective of all concerned!

Keeping in mind that tropical cyclones normally approach the Port of Pusan from the south-southwest, the following guideline is offered for the more common "threat" situations (any tropical cyclone expected to have a CPA within 180 nmi of Pusan):

Evasion to the Yellow Sea is the best option available. Because tropical cyclones normally begin to weaken as they move over the relatively cooler waters of the Yellow Sea, the recommended evasion procedure is to sortie into the Yellow Sea and maneuver to place the ship in the navigable semicircle (the left semicircle with respect to the storm's direction of movement) of the storm's circulation and ride it out.

In all cases, the timing of the evasion is affected by:

* The time required to make preparations to get underway
* The time required to reach open water and gain sea room
* The forward speed of the tropical cyclone
* The radius of hazardous winds and seas that can adversely impact a vessel's ability to reach open water.

As stated during the Site Visit in May 2009, ROKN deep-draft vessels normally sortie to the west and may use the Non-Tidal basin in Inchon.

Remaining in Port

Remaining in the Port of Pusan pierside or at anchorage is not the recommended course of action.

Pusan is not considered to be an adequate haven pierside or at anchor for U. S. Navy ships in a tropical cyclone situation. The reasons for not remaining in port include:

(1) The lack of protection from wind in the Harbor,
(2) The susceptibility of Pusan Harbor to storm surge, and
(3) The vulnerability of the anchorages from high winds and seas.

All U. S. Navy ships capable of getting underway should sortie from the Port if Pusan is threatened by a tropical cyclone.

For those vessels moored to Pier 8 and incapable of getting underway due to mechanical problems, the following precautions are recommended.

(1) All items capable of becoming flying projectiles in a strong wind should be removed or otherwise secured.
(2) Extra attention should be given to the mooring lines and to the brow during the passage of the storm. Crews should have extra line and wire available and be ready to tend lines during the storm's passage. Yokohama fenders should be placed between the ship and the berth unless a camel is used.

Based on discussions with the Port Authority during the Site visit in May 2009, in a worst case scenario a deep-draft vessel would probably be required to drop anchor in the North Inner Harbor vice staying moored to the pier.