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SEARCH and RESCUE ( SEARCH PATTERNS )

Here are some search patterns that you could use if a vessel or aircraft went down.

In any situation, think about this while doing a search

(1) what are you looking for? ship - Liferaft - man in the water.

With all of the above you must then take the following into consideration.

(a) The weather
(b) The strength of the tide
(c) The wave height
(d) The temperature of the water

with the above information and regarding the following, then think about this

Sea is like a mirror, then the searches can be pretty wide
Storms, large waves and strong tides, then the searches must be very tight

There are various searches that can be carried out, the following searches are recognised in the IMASAR Manual.

Expanded Square Search

Downwind for 1 miles, alter to starboard 90 degrees, go down this course for 1 mile,
Then
Alter 90 degrees to starboard and go down this course for 2 miles
Then
Alter 90 degrees to starboard and go down this course for 2 miles
Keep adding 1 mile ever time you alter to starboard

These distances are just for examples

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Sector Search Pattern

Go Downwind for 1 mile,
alter 120 degrees to starboard, this course for 1 mile
then
Alter to starboard 120 degrees and go on this course for 2 miles going through datum
then
Alter to starboard 120 degrees for 1 mile
then
Alter to starboard 120 degrees for 2 miles going through datum
then
Alter to starboard 120 degrees for 1 mile
then
Alter 120 degrees to starboard for 1 mile back to datum
then go down the Blue track as follows
Alter 30 degrees to starboard for 1 mile
then go to the above and do the same again
then go down the Black tracks as follows
Alter 30 degrees to starboard for 1 mile
then go down the above and do the same again

These distances are just for examples

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Parallel Search Pattern

With this search it can be done with 1 or more vessels
The main vessels starting the search are the two back arrows next to datum (Black square)
They will go up past datum and after a certain distance will turn away from each other at 90 degrees
then at very short distances on this track will turn and go parallel to each other on reciptical courses
they will do this until told to stop

Other vessels (Red arrows) will take the next berth alongside the main 2 search vessels and also turn away from each other

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Williamson Turn

For this demonstation, assume your going Due North

Turn towards the side that the man fell overboard, (in this case he's fell over the starboard side)

Alter till you see 060 degrees on your compass

Alter hard to port till you see 200 degrees on your compass

Square up your helm to amidships, this will take you down on a reciptical course

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ALONGSIDE TOWING

For tugs working inside harbors and for towing short distances or in confined areas where constant control is required, towing alongside or the hip tow is the preferred method. A hip tow can be made up on either the port or starboard side of the tug. There are various ways of making up a hip tow, here are some standard things to keep in mind.

Making Up a Hip Tow
Three lines should be used, the spring line, the bowline, and the stern line. For large or heavy tows, you may want to double up on the towlines and also use a bow breast line. Before the tug goes out to make up for a hip tow, the towing lines must be inspected and made ready. Inspect the lines for signs of chafing and the eyes and the eye splices for fraying or breaks. Check the towlines for wear and breaks. If you find a line damaged or one that you have doubts about, point it out to the operator. When selecting the lines to be laid out, the usual procedure is that the best line is used for the spring line. This serves as the towline and takes the greatest strain. The second best line is used for the bowline, and the third best line is used for the stern line. The lines are then faked down (they are laid out so that they are free of kinks and obstructions). They can then be paid out rapidly when they are needed.

DETERMINING WHICH SIDE TO MAKE UP TO
The tug secures to one side of the tow with her own stern abaft of the stern of the tow. This will increase the effect of the tug’s screw and rudder. The side chosen depends on how much the tug must maneuver with the tow.

If all turns are to be made with the tug’s screw going ahead, she will be more favorably placed on the outboard side of the tow, the side away from the direction toward which the most turns are to be made.

If a sharp and difficult turn is to be made under headway, the tug should be on the side toward which the turn is to be made. Here she is placed for backing to assist the turn, because as she slows, the tow’s bow will turn toward the side the tug is on.

If a turn is to be made under no headway, the tug is more efficient on the starboard side of the tow. When the tug backs to turn, the port send (side force) of her screw will combine with the drag of the tow to produce a turning effect greater than that which could be obtained with the tug on the port side.

The best position for a long back in a straight line is to have the tug on the port side. Then the drag of the tow tends to offset the port send of the backing screw.

SECURING THE TOWLINES
The towing line or spring line, usually a 6-inch (or larger) hawser, is led from the forward towing bitts on the tow side of the tug to the aft set of bitts on the tow. This line is secured first. Then the tug eases ahead with her bow turned in to take out all of the slack.

Next the bowline or backing line is paid out over the outboard side of the bow stem or king post and lead to a bitt on the forward end of the tow. Once the bowline is secured on the tow, all the slack is taken in and the bowline secured. This will bring the tug into proper position, slightly bow-in to the tow. When backing down, the bowline becomes the towline.

The stern line or turning line is lead from the tug’s stern to the outboard side of the tow’s stern. The purpose of this line is to keep the tug’s stern from drifting out. The three lines, when properly secured and made taut, will make the tug and tow work as one unit.

Note: If for some reason the stern line cannot be fair led and secured to the outboard side of the tow, it is then secured to the inboard bitt on the stern of the tow.

A fourth line (optional), the bow breast line, can also be used for greater control when making up to a heavy tow. Check all the lines to ensure that they are as taut as possible. Perform this by easing the tug forward, then aft, to see that all the towlines are secure. The tug and the tow should be made up as a single unit.

CAUTIONS:

1. When securing these towlines, remember, NEVER secure the line so that it cannot be thrown off quickly and easily.

2. The tug and tow seldom pitch in the same manner. When both start pitching the lines take a heavy strain and may part. When equipped with a rudder the tow assists in steering. Size and loading of the tow may obstruct the view of the tug’s operator. In that case, a lookout is stationed aboard the top who keeps the operator informed of activity and hazards in the blind area.

BASIC TOWING

TYPES OF TOWS

The use of tugs and their connection to the tows can vary. The following are some basic types:

Single tug, single unit tow.
Single tug, multiple unit tow.
Multiple tug, single unit tow.

SINGLE TUG, SINGLE UNIT TOW
This consists of a tug and tow. Several methods are used in connecting the tug and tow. The single leg and bridle or stern tow is used for long distance towing in open waters. The alongside or hip tow is used where maximum control and maneuverability are required.

The single leg and bridle is made when the towing ship passes the towline, which is shackled to a flounder plate at the apex of the bridle. Each leg of the bridle consists of chain or wire rope passed through the bow chocks and secured on the tow’s deck to padeyes or bitts.

Towing alongside (hip tow) is most often used in congested waters. Towing alongside offers excellent control, it is not recommended for the open ocean. For alongside towing, the tug generally secures to one side of the tow with her own stern abaft of the stern of the tow to increase the effect of her screw and rudder. The side chosen depends on how much the towing ship must maneuver with the tow.

SINGLE TUG, MULTIPLE UNIT TOW
This consists of one tug and several tows. The connection and makeup of the tows can vary. The following are the three used for towing astern:

Christmas Tree rig (for long distance in open ocean towing).
Honolulu rig (for short distance towing).
Tandem rig (for congested waters where control is required).

MULTIPLE TUG, SINGLE UNIT TOW
It may be desirable to use more than one tug for only one tow. Greater power, increased towing speed, and better control may be obtained in a multiple tug tow. This type tow is generally used in towing large ships, deep-draft, large-displacement dry docks, or deep-draft barges.

ZONE TIME OF LOCAL APPARENT NOON (LAN)

Local apparent noon (LAN) is a sight taken on the Sun at the instant it transits an observers meridian. At that time, the Sun is at its highest altitude. The purpose of observing the Sun at LAN is that it allows you to establish your latitude.

The purpose of determining watch time of LAN is merely to enable you to arrive on the bridge within a few minutes of the time you should take your sight. Since zone time of LAN is based on your dead reckoning (DR) longitude, the exact moment it transits over your meridian will seldom be precisely calculated, but you should be able to figure it very closely.

The Greenwich Mean Time of meridian passage, or GMT Mer. Pass, is found on the lower right daily pages of "The Nautical Almanac" just below the sunset table. This is also the time that the sun will be over any standard meridian, no matter what zone you maybe in. Below is an excerpt from the Nautical Almanac that shows you how this information appears. Be sure that you use the page for the appropriate date. 12 Febuary, 1981. All the Coast Guard test question’s are based on using the 1981 Nautical Almanac.

Excerpt from Nautical Almanac time of meridian passage for Febuary 12, 1981
		DAY	SUN		Mer.
			Eqn. of Time		Pass.
			00h	12h
		12	1417	1417	1214
		13	1417	1416	1214
		14	1415	1414	1214

To compute the time of the 1st Estimate of LAN, I use a step by step process using the form shown below.

Problem 1 : On 12 Febuary 1981, your 0930 zone time DR position is LAT. 25° 20.0 N, LONG. 30° 40.0 W. Your vessel is on course 135° T at a speed of 11.2 knots. What is the zone time of local apparent noon (LAN) ?

A. 1210

B. 1215

C. 1220

D. 1224

DATE	12 Feb. 1981
MER. PASS.	1214
DR. LONG.	30° 08.0 W
STD MERIDIAN	30° W
d Long.(arc)	0° 08.8
d Long. (time)	+ 0m 32s
ZT LAN ( 1st Est.	12h 14m 32s = 1215

Step 1: Enter the appropriate date.

Step 2: Go to The "Nautical Almanac" and extract the time of meridian passage for 12 Febuary 1981.

Step 3: (a) Set up universal plotting sheet.

(b) Plot 0930 DR position and DR ahead to 1214.

1214

- 0930

3h 44m at 11.2 knot = 41.8 miles

Step 4: Enter your DR longitude for the time of meridian passage you extracted from the almanac (1214).

Step 5: Enter the nearest standard meridian.

Step 6: Calculate the difference in arc between the standard meridian and your DR longitude.

Step 7: Convert the arc in into time using the "Conversion of Arc to Time" from the Nautical Almanac.

Step 8: Now apply the time correction to the time of meridian passage from the almanac. Because you are west of our standard meridian, you must add the difference. By applying this correction you will have the time of LAN at the meridian for your DR position. This is called the first estimate of LAN.

Note: if you clocks are set to daylight savings time (DST), add one hour to your zone time or use the standard meridian that your clocks are set to.

TEMPORARY EYE IN WIRE

A temporary eye may be put in wire by using wire rope clips. A wire rope clip consists of two parts, the U-bolt and the roddle, the part into which the U-bolt is inserted. You should always put the U-bolt over the bitter end and the roddle on the standing part. This protects the live or stress-bearing end of the rope against crushing. The roddle protects the rope and, should always be placed against the live end.
To get maximum strength from the temporary eye splice, use the correct size and number of wire clips, and the correct spacing between them. Size is stamped on the roddle between the two holes. Use the following formula to determine the number of clips: 3 x diameter of wire rope + 1 = number of clips. For example, the number of clips needed for l-inch wire rope is: 3 x 1 + 1 = 4. To determine the correct space between clips, multiply the diameter of the rope by six. For example, the space between clips to be put on 1-inch rope is: 6 x 1 = 6 inches. Measure the space from the center of one clip to the center of the next one. If the calculation for either the number or the space results in a fraction, round off to the next higher whole number.

(Molly Hogan) Splice. Sometimes you have to put a splice in fast, you can do this with the Molly Hogan splice. This splice can be quickly made, but it is limited to about 70 percent of the strength of the wire rope. It should not be used to lift heavy loads. This splice can be used only when working with preformed wire rope. To make a hasty eye splice, personnel should follow these steps:
(1) Using a marlinespike, screwdriver, or, if necessary, a nail, separate the wire rope into two three-strand sections. These sections should be unlaid four times the diameter of the desired eye. If you want a l-foot diameter eye, unlay the sections back 4 feet.
(2) Use the two sections to form a loop of the desired diameter for the eye.
(3) Lay the strands back around each other to form the eye.
(4) After the strands have been laid back around each other and the eye has been formed, seize the wire to complete the splice.

SHORT SPLICE

Splicing is a method of permanently joining the ends of two lines or of bending a line back on itself to form a permanent loop or an eye. If two lines are to be spliced, strands on an end of each line are unlaid and interwoven with those of the standing part of the line. Small stuff can be spliced without a fid, which is a tapering length of hard wood used in splicing larger lines. A knife is used to cut off the ends of the strands.

Short Splice - The short splice is as strong as the rope of which it is made. The short splice increases the diameter of the rope and can be used only where this increase in diameter will not affect operation. The splice is used to repair damaged ropes or where two ropes of the same size are to be joined together permanently. Damaged parts of the rope are cut out and the good sections are spliced. These are the steps

(1) Untwist one end of each line five complete turns. Whip or tape each strand. Bring these strands tightly together so that each strand of one line alternates with a strand of the other line. Put a temporary whipping or tape on the lines where they join to keep them from coming apart. Do this procedure with small lines until you can hold them together while you tuck. 2) Starting with either line, tuck a round of strands in the other line. Then, using the strands of the other line, tuck a round in the first line. Make sure to tuck in one direction, the reverse and tuck in the other direction. When making a round of tucks, regardless of the direction, face where the lines are butted so you will always tuck from right to left. Pull each strand as to tighten the center of the splice.
(3) Tuck two more rounds in each direction. After tucking in one direction and reversing and tucking in the other direction, pull the strands as required to strengthen the center of the splice. When finished with three rounds of tucks in each direction, cut off any excess length on the strands.

NOTE: To have a smoother splice, cut off one-third of the circumference of each strand before making the second round of tucks and another third before the third round.
(4) When the splice is completed, cut off the excess strands as before. Lay the splice on the deck and roll it with your foot or hands to smooth out and tighten the splice.