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HARBOR ENTRANCE DES IGN: A PILOT'S VIEW Captain Thomas G. Knierim I am a New York ship's pilot, and my topic is pilots' concerns. After any and all the engineering and theoretical studies for harbor design have been developed and a vessel arrives at the entrance to this harbor, I am the one who must make the round peg fit into a square bole, or explain why it doesn't fit. It seems that in the past as the shipping of the day grew in size and draft, and problems arose, channels were enlarged just enough to permit those vessels to move under favorable conditions. A point seems to be the busy Houston Ship Channel which is dug case in to a width or Mu teet and continually accommodates tankers in the 100,000 DWT class. A pilot told me the U. S. Army Corps of Engineers will not widen the channel because there are not enough accidents to warrant it. It would seem that to lobby for a safer channel you must first become more slovenly in your piloting techniques. We wait for a calamity before doing anything constructive. To strengthen this point--though I know only some of the newspaper accounts of the tragic Tampa Bay accident--it was reported that a member of the state bridge commission (after several prior accidents) likened protection around the bridge tower dock structures to placing a metal shield over every home in the United States for protection from falling aircraft. Nonetheless, such protection has been placed around several New York bridges with satisfactory results. It must be said that we, the practical navigators, are quite skeptical about relations with government agencies. In cases such as harbor traffic control, rather arbitrary decisions have been made. To understand the pilots' views on harbor and port entrance design, we must really take into account the needs of both the foreign mariner arriving at a strange port with a large, fully laden vessel and attempting to find his pilot, and the pilot coming aboard a vessel foreign to him. The pilot is required to locate the ship's position and to provide safe, economical pilotage aboard this unfamiliar ship during the day and night and during all extremes of weather. In both instances, our needs can be expressed as the questions, Where am I? Ship's position), Where do ~ want to go? (local knowledge), and, How do I get there? (ship-handling ability). The last two represent the necessary ingredients of pilots. 95
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96 The question, Where am I? in a major seaport demands an outstanding aid to navigation equipped with a major light, sound signal, radio direction finder, and racon, etc., to distinguish it from all other aids or vessels. It is then an incoming beacon for the approaching mariner and a point of departure for a pilot. In a small port, such as Bridgeport, Connecticut, when approaching from the west, a light ahead (Stratfort Point Light), and when close to the mid-channel buoy, a light abeam (Penfield Reef Light), is ideal. Where am I going? As a pilot, my primary desire is a wide channel. It might be said that as the roadstead widens and becomes good water, as in a fjord or some sounds, the need for navigation aids lessens. Should we dig a channel this wide, our need to mark it diminishes or becomes nonexistent. Conversely, as the channel narrows, the need to mark it well increases. A 2000-foot-wide channel, such as Ambrose leading into New York, is regularly run in poor visibility using radar, without undue apprehension. As the channel continues to diminish in width to, say, S00-800 feet, the potential for near-misses and collisions increases at an accelerating rate. The entrance to a well-marked channel should, whenever possible, be marked with a mid-channel buoy, one to two miles off shore from the buoyed channel to give a good approach. The most valuable aid to navigation today, and the most basic aid, is a well-lighted sound buoy. Properly placed, in position, and in sufficient number, they indicate within a number of feet where the channel limitations are. Whenever possible, buoys marking channels should be sated. There seem to have been few changes to buoys in years, and their total number in an age of increasing ship size does not seem to have increased. Interestingly, when we ask for a buoy to mark a particular point, we often hear, "Glad to move one, where should we move it from? You get the feeling that not a single buoy has been built since my grandpa worked for the lighthouse department. Since buoys can move, some permanent structures should be considered, especially near turns in areas experiencing difficulties from ice or storms, or where they are often dragged by vessels. Lights should also be maintained under bridges to mark channels. Another basic useful aid to a mariner is a set of range lights. They are particularly valuable in the first leg of a channel, where there is a greater chance of tidal set. Entering or exiting a port such as Port Jefferson with a 300-foot channel at night in a winter gale, the range is used almost to the exclusion of the buoys. Electronic gadgets have emerged during the 20th century, notable for their advancement of navigation and also for their degree of unreliability during times of stress. During a symposium several years ago, an officer of Gulf Oil discussing collision avoidance systems (CAS), said his company experienced a breakdown rate of about 5 percent with the radar and about the same with the CAS, creating a multiple of unreliability for the CAS. Our most-used aid, the radar, the pilot uses aboard an unfamiliar vessel. The radar may be in almost any state of repair or tuning. It must be considered that we shrink a three-mile radius into about a foot on the three-mile range. Therefore, determination of position in, say,
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97 a 2000-foot channel, which is about the width of my thumb, is truly by rule of thumb. Loran and Deca will give a position within 50 feet or so in some areas. However, aboard merchant ships, personnel is insufficient to keep an up-to-date running check as a cross-reference for the pilot. We have Dopplers and rate-of-turn indicators that can be useful, but in a channel situation, these are difficult to incorporate fully into navigational procedures. This brings us to a quite interesting aid, used today in the man-made port of Antifer, near Le Harve, France, which quite possibly could have prevented the tragedy in Tampa Bay--the transponder. During experiments with this device (for example, in channel situations at the Computer-Aided Operations Research Facility), a very informative readout was obtained regarding longitudinal position from the channel's center-line, and the rate at which the vessel was transversing either left or right. It also gave a readout for the distance to the next turn. A system that uses a shore station, when receiving signals from two transmitters located fore and aft on the centerline of the vessel, instead of just one transmitter at the center of the ship, will also give the vessel's rate of turn in a bend. Pilots are as interested as anyone in navigational advances for harbor and entrance design. However, we must stress that electronic aids be provided in addition to a complete set of basic navigational aids, and never to the exclusion of those aids. I have purposely disregarded the depth of the channel, which I personally like at least 1.2 times the ship's draft for ease of handling. This is because pilots must often exercise their abilities in less than ideal conditions. If a vessel will float, we will move it safely at a slow rate. I have also omitted vessel traffic control because so much has been said about it lately. Vessel traffic control should aid the mariner, not add to his burden. DISCUSSION MAGOON: I would just like to make a comment. For many of the channels, at least the federal channels that are constructed and maintained by the Corps of Engineers, some of the problems you mention come up in public hearings when the project is under review. If the problems need review, a resolution is introduced in Congress and a study is authorized of the particular channel. On the study's completion, the recommended changes would be made. WEBSTER: One of the problems, I would imagine, with port design is that you have to design the port so that many different types and sizes of ships can come through it. I was wondering whether you have any insight into the most demanding types of ships that you have to drive through the New York harbor. Are the biggest ones the hardest to handle? Do you have any feel for what it would be that is the most critical in handling?
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98 KNIERIM: Some of the larger ships, passenger ships, are quite easy. Loaded tankers are difficult ships to handle because of their size and weight. I think something that has been found, though I haven't handled a VLCC* as such, is that the control of these ships, with the amount of mass that they have, the forces created by their movement through the water, and various interactions place demands on the pilot. The SL-7s, because of their size and handling abilities, are very difficult ships. The most difficult part of the SL-7 pilotage in the New York harbor is done by the docking masters and not by the sea pilots. One cliff iculty in piloting an SL-7 is that the wheelhouse is all the way forward. The pilot therefore has lost a lot of his perspective, being right on the bow. He doesn't get a feeling of the ship's mass, and he can't see just what the ship is doing, so the pilot usually doesn't stand there, but prefers to stand more or less in the midship house where some of the stacks are. He gives his commands by radio to the pilot who is in the wheelhouse, and it is then passed on to the quartermaster for steering. Interestingly, if he tells them that be wants 10 degrees right rudder, they put the rudder over 10 degrees right, but the tugboat on the stern starts working slow a bead on the starboard quarter. If he increases the rudder to 20 degrees right rudder, the tugboat on the quarter increases speed to half ahead on the starboard quarter and if he says hard right, the tugboat hooks it up. Those ships don't handle well, and pilots derived the system of turning them with their rudder commands, automatically giving a signal to the tugboats and assistants to help them turn. Container vessels, because of their size and the sail area in a good breeze or wind, are most difficult to handle, and require special caution. LE BACK: As a pilot, would you support or advocate moving the pilot boarding area farther out to sea, for those large vessels particularly? Licensing would have to be changed and extended, and of course, the question of additional pilot fees for extending this pilot ground further to sea would have to be resolved. Would you support something like that if it were in the interest of the safety of the port? KNTERIM: The captain of a foreign, heavily laden ship coming to the port for the first time is apprehensive. There should be a good light, a good beacon, bringing him in so he knows where be is, but there should be no reason for him to be overly apprehensive. The assumption of pilotage should take place long before the ship is in any real danger. There should be time for the pilot to come aboard the ship and to receive the command from the captain without any difficulties occurring before or during the passage of the command to the pilot. Therefore, I should say that if the pilotage area is not sufficiently offshore for that particular type of ship, moving it farther out should definitely be considered. *Very large crude carrier.