Shortly before ten o’clock, Carstens noticed that Chief Officer Herbert Kallback had come up to the open deck of the bow where three seamen had been on their hands and knees all evening scrubbing down the wooden deck of the bow. It was to be polished with oil the following morning as a protection against the salt air and sea spray. The chief officer, as usual, was carrying a black flashlight in his left hand like a general with a swagger stick. Carstens watched as the chief officer inspected the work on the foc’s’le deck, then apparently approving the progress of the work, called a halt for the night and led the men off the bow.
Shortly afterwards, Captain Nordenson came into the wheelhouse and announced he was going down to his cabin and would be there if needed. “Call me when you see Nantucket,” he told the third officer. Neither man could remember the short, casual conversation afterwards. Whether the captain had said anything about the possibility of fog or not, neither man could recall. If he had, it would have been superfluous, they said later. Carstens knew of Captain Nordenson’s standing orders that he was to be summoned at any time of day or night in the event of fog or any other potentially dangerous event. Captain Nordenson went down one deck to his cabin to catch up on some paper work for the two hours before he would be needed on the bridge to make the change of course upon reaching the Nantucket Lightship. It was his practice not to retire on the first night out until after the lightship had been passed.
When the captain had left the bridge, Carstens noticed the time and decided to determine the position of the ship. Nantucket Lightship, about 40 miles ahead, was now within range of the ship’s radio direction finder, Carstens thought. Before leaving the wheelhouse, however, he checked the radar to be certain there was no ship within 15 miles of the Stockholm. He called his standby, Peder Larsen, from a small room behind the wheelhouse to stand lookout on the bridge and he glanced at the gyrocompass to make sure the helmsman was steering the desired course of 87°.
In the chartroom Carstens switched on the radio direction finder, which working on batteries was ready for instant use, tuned it to 314 kilocycles, and turned the compass wheel eastward to pick up the radio beacon signal of the Nantucket Lightship. The signal was loud and clear in his earphones. Carstens zeroed it carefully to minimum and, reading the bearing on the compass, he laid off a corresponding line on the chart. Then he swung the wheel of the direction finder to the northwest to pick up the radio beacon signal of Block Island, which the Stockholm had passed three hours before, and drew that bearing line on his chart. Where the two lines intersected was the position of the ship at 10:04 P.M. by the electric clock on the chartroom wall. As an additional check he noted by the ship’s echo sounder that the depth of water beneath the ship was 35 fathoms and that corresponded with the depth noted for that position on the chart.
Thus, in about three minutes time, Carstens fixed the position of the ship with a fair degree of accuracy. The Stockholm, he saw, was two and one-half miles north of the course set by the captain.
Carstens returned to the wheelhouse and checked the radar. The flasher showed no ships or obstructions on the radar scope. Two and one-half miles off course was not very much at this point of the voyage, Carstens thought, but he decided to recheck his position again in a half hour before taking any corrective action. He checked the tide tables too, which convinced him that the currents were setting the Stockholm northward.
At 10:30 P.M., he took another RDF position. This time, he not only took bearings on Nantucket Lightship and Block Island but he also took a third bearing on the Pollock Rip Lightship some 60 miles to the north. The three bearings left no doubt. The Stockholm was now two and three-quarter miles north of the projected course line. He would have to correct for the northerly currents.
Carstens walked back into the wheelhouse. “Steer 89,” he told Johansson.
“Eighty-nine, yes, sir,” responded the helmsman, turning the wheel slowly to the right as he watched two degrees click off on the gyrocompass.
Carstens had made his first independent decision of the routine watch, then two-thirds over. He turned the numbers in the course box to read 089. The two-degree change to the south, or to the right, would compensate for the northerly set of the current, he expected. At any rate, he decided he would check his position again in another half hour.
A few minutes later, at 10:40, Peder Larsen took over the helm from young Johansson for the final third of the watch. Johansson relieved Bjorkman in the crow’s-nest and Bjorkman went to rest his feet in the standby room.
Carstens continued to pace the bridge on watch. There was a slight haze on the horizon but visibility continued to be good. Each time Carstens walked out to the bridge wing, he glanced up at the crow’s-nest to see that the lookout was alert, and further up the mast to confirm that the navigation lights were burning clearly. Every three minutes or so he inspected the radar scope for a sign of any ship.
Carstens, as he paced the bridge, paid particular attention to Peder Larsen at the wheel. This was Larsen’s first voyage on the Stockholm although he had had eight years of previous sea duty.
Carstens thought Larsen could steer the ship well enough when he kept his mind on what he was supposed to be doing. But the Danish seaman seemed to have an insatiable curiosity about what was going on about him and he carelessly allowed his attention to wander from the compass he was supposed to watch. That was all right for the steering of a freighter or a ferryboat, Carstens thought, but Larsen would have to learn that a helmsman was expected to keep a passenger liner on a tight, straight course within one degree of the desired course line. Larsen allowed the Stockholm at times to yaw two, three and even four degrees to either side.
Aware of this trait of his helmsman, Carstens sought to keep a tight rein upon him. Each time he walked through the wheelhouse, which was every three to five minutes, Carstens pointedly stopped to look at the compass by which Larsen was steering. The helmsman could have no doubt that the officer was checking his steering and the wordless reminder was enough to turn Larsen’s eyes upon the compass.
As for the helmsman’s point of view, Larsen had complete confidence in his own ability to steer the Stockholm, or any other ship. He just did not see the necessity for keeping his eyes glued to the compass like a robot. A glance at the compass and the feel of the wheel in his hand sufficed, he thought, and despite the yawing of the ship he did make good the course he was to steer by.
Carstens, more concerned about the possible drifting of the Stockholm off course, wanted to take another RDF fix to determine what effect his two-degree change of course at 10:30 P.M. had made in the Stockholm’s position. He checked the horizon visually and by radar for any other ships and, finding none, called Bjorkman from the standby room to stand lookout watch on the bridge while he was in the chartroom.
Carstens took this fix on the radio beacons of the Nantucket and Pollock lightships. As he did with the other RDF position fixes, Carstens noted on the navigation chart the mileage on the log and the time. It was actually 10:48 P.M., if one computes the time by the ship’s speed and distance from the previous fix, but Carstens noted the time as 11 P.M. Why he did this, he could never explain. This inaccuracy was to plague him in the months ahead, but he could not know that at the time. Nor could he foresee even 21 minutes into the future.
What concerned Carstens at the moment was that the Stockholm, despite the two-degree change in course, was now three miles north of the projected course. The tide was causing the ship to drift progressively farther to the north. At 10:04, the ship had been two and one-half miles off the course line; at 10:30, she was two and three-quarters miles off, and now three miles off.
Carstens strode back into the wheelhouse and ordered another two-degree turn to the right. Larsen eased the wheel to 91 degrees as Carstens checked the radar scope. This time he saw the “pip” of a ship.
The pip was small and faint, a yellow dot appearing at a distance of 12 miles and just slightly off to the left of the Stockholm’s heading f
lasher. Bending over the radar, with his eyes focused on the spot where he had seen the pip, Carstens tried to adjust the set for added brightness to bring the pip into better focus. But it remained dim and small. He decided to wait until the pip showed the vessel to be 10 miles away. Then, he told himself, he would plot the course of the ship on the Bial Maneuvering Board set up beside the radar scope. The maneuvering board, 14 by 18 inches, corresponded to the radar scope. By plotting the other ship from 10 miles away, he could allow one mile for each concentric ring of the maneuvering board and obtain a larger diagram than by plotting from 12 miles and halving the value of the ten concentric distance rings.
Radar is one of the most simple devices of the electronic age, so simple as to be deceiving. It is in the misuse of the instrument or the misinterpretation of what it tells you, that navigators go wrong so often.
The radar set on the bridge of the Stockholm, which is not materially different from those on any other ship, has a round television-like screen which is dark except for illuminated hands originating in the center of the scope like the hands of a watch. The scope is a cathode tube which always shows the home ship to be in the center and stationary. One hand, the ship’s heading flasher, always points upward to 12 o’clock. Another hand, the flasher, circles the scope about 12 times every minute continuously, in synchronization with the ship’s revolving radar antenna atop the mast. Any object struck by the very high-frequency radio signals emitted by the set through the antenna appears on the radar scope at the appropriate distance and bearing. The outer rim of the circular scope is marked off with the 360 degrees of a compass. With the heading flasher on the course of your own ship, you can determine the relative position of the other ship at that given instant by noting its bearing in relation to your ship. This is done by putting the third hand, called the cursor, which is similar to the alarm setting hand of a clock, on the pip and noting the number of degrees it is away from the heading flasher.
Because one observation is true for only the instant it is made, at least two observations must be plotted on a paper or device similar to the radar scope in order to determine the course of the other ship in relation to your own ship—provided neither ship changes course. Only by plotting at least three observations can one see if a ship is changing course. And only by timing the various positions can one determine the speed of the other vessel. And then, with a bit of trigonometry, one can simply determine the true course of the other vessel.
In the dark of the wheelhouse, Carstens switched on and adjusted the light beneath the plastic surface of the Bial Maneuvering Board, lighting it like the dashboard panel of an automobile so that the numbers and lines on the board could be seen and yet no light reflected into the dark wheel-house. He adjusted the compass ring around the radar scope to the 91-degree course of the ship and watched the pip of the other vessel until it reached 10 miles distance. At that exact moment he asked the helmsman for the actual heading of the Stockholm. Larsen sang out, “Ninety degrees.” The pip at that moment was one degree to port. Adding the one degree difference from 90 to 91, he marked an X on the plotting board two degrees to port and 10 miles away. With a glance back at the chartroom wall clock, which he could see through the open door, Carstens noted the time of his observation. Later he could not recall it.
The young officer watched the pip on the radar for several seconds to determine that it represented a ship coming toward the Stockholm. This was not unusual on the Stockholm’s route from New York to Nantucket. It was expected.
Carstens, informing Bjorkman of the ship, ordered him to stand lookout on the port wing of the bridge. After the ship had been safely passed would be time enough for Bjorkman to rest in the standby room.
Carstens walked from the radar to one wing of the bridge, looked out to sea, walked back to the radar to check the pip of the other ship, and then went to the other bridge wing to scan the horizon. The night, it seemed to Carstens, had not changed. The moon shone overhead and the sea remained calm.
He plotted the pip of the other ship again with the help of the helmsman. It was six miles away and four degrees to port. Giving his entire attention to the exact marking of the other ship’s position, he was unaware of the bridge clock ringing six bells for 11 P.M. Larsen at the wheel, however, responded by pulling the lanyard over his head for six chimes on the ship’s bell above the wheelhouse. It was his duty as helmsman to sound the hour to the whole ship.
Captain Nordenson in his cabin below the wheelhouse noted the six bells and, pausing in his writing, thought he would soon have to go up to the bridge for the approach to the Nantucket Lightship. But he did have a half hour or so before the lightship would be picked up on radar. He continued to write in his personal diary: Beautiful weather and warm, a slight haze on the horizon. 1131 departed from New York. Sent a letter to my Sonia, darling [his wife]. It’s very nice to get away from the heat in New York.
Carstens on the bridge neglected to note the time for his six-mile observation. He looked out at the black night beyond the port bow of the Stockholm, expecting to see the mast head lights of the other ship.
He had, of course, full confidence in his radar. The set had been checked and calibrated for accuracy the day before the ship sailed from New York. Yet good seamanship, as Carstens had learned it in school, called for him to wait if possible until he visually sighted the lights of the other ship before taking action. And he expected to see the lights then or at any moment at about 20 degrees off his port bow.
He had marked an X on the plotting board corresponding with the range of six miles and four degrees to port. Then he ruled a straight line between the X’s, noting that it showed the bearing of the other ship was increasing and that the ship would pass—if neither one changed course—to the left of the Stockholm at a distance of between one-half and one mile. He decided he would have to turn to the right to increase the passing distance because Captain Nordenson’s standing orders were never to allow another vessel to come within one mile of the Stockholm.
He expected to have plenty of time before the ships met to turn the Stockholm to the right and execute the usual port-to-port, or left-to-left, passing. This was in accordance to Rule 18 of the International Rules of the Road: When two power-driven vessels are meeting end on, or nearly end on, so as to involve risk of collision each shall alter her course to starboard, so each may pass on the port side of the other.
Having plotted the course of the other ship, Carstens walked to the starboard wing of the bridge where he told lookout Bjorkman, “Keep a sharp lookout for a ship on the port!”
This was all routine. Carstens was not in the least concerned. He had executed this maneuver many, many times before. Port-to-port passings were the pactice at sea. It is only when meeting a ship at sea starboard-to-starboard that a navigator must make a basic decision. The accepted practice in a right-to-right passing situation in open waters is for both ships to turn to their right early enough to execute the usual port-to-port passing. It is only when the two ships are so far to the right of one another that it would be dangerous to attempt to cross over for a port-to-port passing, that the starboard-to-starboard passing is acceptable. And then, the law courts have held, the ships must pass on each other’s right side without having to alter course. But Carstens did not have this to concern him: the ship he saw on his radar was on his port or left side.
As he peered into the dark night, however, he began to wonder why he did not see the lights of the other ship. The radar told him the other ship was a fast one. But what size ship or what type ship, he could not tell. He saw the radar pip of the ship advance to within five miles of the Stockholm and still he could not sight the vessel.
The underlying principle for all the Steering and Sailing Rules of the Rules of the Road is stated in the preliminary: In obeying and construing these Rules, any action taken should be positive, in ample time, and with due regard to the observance of good seamanship. This is the basic safety rule of all the regulations promulgated to
prevent collisions at sea. It means that in taking advantage of the relatively slow speed of ships, and overcoming the disadvantages of poor braking or stopping power of ships, every change of course taken to avoid a collision must be taken early and must be a bold or sharp action or change of course. Only a bold alteration of course, one of at least 20 degrees, can be easily seen from another ship. And it must be taken far enough away from the other ship that NO MATTER what the other ship does, there can be no collision. This is prudent seamanship!
When the oncoming ship was four miles away, Carstens turned the knob of the radar set to the close-up range of five miles. The pip became enlarged, taking the shape of a yellow bean on a black background. The illuminated flasher circled the screen indicating no other ships in the vicinity. Although Carstens did not bother to notice the time, the bridge clock showed 11:03 P.M.
Again he peered into the night and now he began to wonder why he did not see the lights. No definite reason occurred to him. Not for a single moment did he think that there might be fog. To him the night seemed clear enough. He assumed visibility was as good for the other ship. It occurred to him that the lights of the other ship might be defective. That did happen sometimes. Ships did steam through the night without running lights, contrary to law. It was possible also that the other ship was a naval vessel on maneuvers, running with her lights blacked out.
Collision Course Page 4