Keeping watch at sea
Just occasionally it is interesting to read how others keep, or kept, a watch at sea.
A recently published book about life at sea in the Second World War describes how officers kept watch on board a submarine as it transited on the surface in hostile waters. They kept their eyes permanently glued to their binoculars for the entire two hours they were on watch as they swept both sea and sky for sign of the enemy. Failure to do so could have meant disaster for both boat and crew. The need to spot a ship, aircraft or periscope in a hostile environment must have been a remarkable incentive to keep a very good lookout indeed.
The circumstances were, of course, very different to the maintenance of a good lookout in a merchant vessel or fishing vessel today. We are not looking for an enemy, but are there to ensure the safety of the ship, its cargo and everyone on board. A collision or grounding can still lead to people being killed or injured.
The need for a good, effective lookout to prevent collisions and groundings, has never been so important. But if the evidence from a number of recent accidents around the world is anything to go by, there are strong indications to show that the standards in too many vessels have slipped very badly indeed. It may no longer be necessary to keep one's eyes glued to binoculars for the entire watch, but there is abundant evidence to show that many of us have forgotten what it means to keep a 'proper lookout,' to ensure the safe passage of the vessel entrusted to our charge.
Keeping a good lookout means using the many available aids sensibly and understanding their limitations. It means looking out of the window and seeing things. It means correlating the radar picture with the visual and, not only knowing what other ships are doing, but spotting any changes they might make at the time. It isn't just keeping an eye open for other vessels. It involves seeing hazards along the proposed track. It means noticing the effects of shallow water in the wash astern, or the extra large wave approaching from up sea. It also means listening for sound signals in poor visibility. Despite modern aids, more than one collision has been successfully averted by watchkeepers taking the correct action on hearing 'apparently forward of her beam the fog signal of another vessel'.
Keeping an effective lookout is a demanding task. It is not an alternative to catching up with the paperwork or reading some erudite publication stowed in the bridge bookshelf.
The failure to keep a good lookout has been addressed in previous Safety Digests but it continues to feature as one of the most common causes of accidents at sea. The endless catalogue of new instances only serves to remind us we assume too much and still have much to learn from the shortcomings of others. Why is it, that with so many aids to safe navigation and anti collision available on many bridges, some officers of the watch get it so badly wrong?
Harping back to the watchkeeper on board a submarine, it is interesting to reflect how his successor in a modern boat running on the surface keeps his watch. With only a gyro repeat, a two-way intercom and a lookout to keep him company on the top of the fin, he has absolutely nothing between him and the elements. His co-watchkeepers are closed up in the control room several deck levels below. He has, in effect, uninterrupted 360°vision and virtually nothing, apart from rain water dripping down the back of his neck, to distract him. It could be argued that this provides the perfect environment in which to maintain an effective watch with the added bonus of being able to look astern and see what the rudder is doing when he orders helm. The top of the rudder is clearly visible above the surface. We do not advocate such austere watchkeeping methods, but it is interesting to reflect that keeping a good lookout in normal visibility does not require much more than excellent eye sight, a compass repeater and the minimum of distractions.
So what are we doing wrong in our well-equipped bridges today? Everyone will have views and many will claim, with justification, that in their ship a proper lookout is kept. But are they right? Take the modern radar. It is a wonderful aid and together with the ARPA has done much to ensure ships can manoeuvre safely in any conditions of visibility. The danger is that officers of the watch rely on it to the exclusion of all else. Radar is good, very good, but it has its limitations. Officers assume it will pick up everything of significance, but anyone who has made a conscientious comparison between radar contacts and what is actually out there, will know that certain objects, such as small yachts, do not paint with sufficient consistency to generate a track. Some radar echoing areas can be very small and there is every prospect that certain small craft will not be detected until they are close. Running down a fishing vessel or yacht can have serious implications for both master and whoever was on watch at the time.
Radar performance can be affected by multipath propagation effects. Transmissions to a target will either proceed direct or will be reflected by the intervening surface. Given certain combinations of radar and target height, sea state and range of detection, the direct and reflected transmissions can cancel each other out so that no return transmission is possible. Although not a phenomenon encountered that often, it can occur and is all too easily ignored. If any junior officer wants to impress the old man with his knowledge of wavelengths etc, he need do no more than mutter something about Fresnel Zones to earn a Brownie point.
It is all too easy to ignore radar blind arcs created by funnels, derricks and, occasionally, by cargo.
It is worth casting one's mind back to college days and those interminable lectures about ensuring the radar is set to maximum performance. Whenever you use the radar make sure it is correctly set up, especially in rough sea states or when (to use that delightful expression) precipitation is in sight. In a sandstorm you have a further problem, radar performance can be severely degraded.
An awareness of the potential limitations will prompt the conscientious watchkeeper to use radar as an aid, and not rely on it to the exclusion of everything else. The good watchkeeper will also remember that radar will not tell him what the other vessel's heading is should he be altering course.
We see instances of watchkeepers assuming the information radar provides as gospel. In thick fog we assume the radar and ARPA enable us to determine whether a close quarters situation is developing, or risk of collision exists. We convince ourselves we know what the other vessel is doing and do not even consider reducing speed. Very sadly we see too many instances where such faith is overly optimistic. An over-reliance on radar, and the common practice of proceeding at full speed in fog, are contributing factors in many collisions.
Of all the instruments available to watchkeeping, man, the Mk 1 eyeball, is still the best providing the visibility is sufficiently good. Man might not, without extensive practice, be able to range accurately by eye, but in every other respect an eye is a superb complement to radar-derived information. Even in fog, there will be someone on the bridge doing his or her best to see things visually at the earliest opportunity.
The best watchkeepers find visual lookout superior to radar, and instinctively revert to the traditional and extremely effective way of determining whether collision exists by taking compass bearings of another vessel to see if they change. One reason for not doing so is that many vessels are no longer equipped with an azimuth circle or pelorus. It is great pity, many an ancient mariner has found them indispensable and never had a problem ascertaining whether risk of collision existed.
The ancient mariner also knew a trick or two about keeping a visual lookout and realised he had to adapt his methods depending on the weather and time of day. He knew about glare and the difficulty of finding the horizon on a dark night. If he wanted to spot a very dim light he knew he was better placed to do it if he averted his gaze by about 2°. The eye makes a much better initial detection when it is slightly offset.
He knew that some sightings are not made on the horizon, and would deliberately look below it for the small vessel or yacht that would first be seen at far closer range. He would know the importance of looking astern from time to time, and always on the engaged quarter before altering course. Some vessels tend to go quite fast these days, and a 5000 teu container vessel proceeding at 25 knots, and overtaking rapidly on the quarter, is a formidable obstacle should you wish to alter course in that direction without looking first.
Maintaining a watch in perfect visibility while 'dipping through the tropics' and not having seen another ship for a week or more, is very different to doing the same thing while 'butting down the Channel in the mad March days.' The watchkeeper in a congested area such as the Dover Strait has to contend with fishermen, yachts, crossing ferry traffic and, perhaps, poor visibility. He may also be tired.
Fatigue remains one of the most common reasons for not keeping an effective lookout. Very often the causes are outside the control of the individual such as long working hours, poor quality sleep, personal worries, and lengthy periods without proper rest. There are, however, one or two things an individual can do to improve alertness and stamina such as drinking a lot of water, taking regular exercise and eating a balanced diet.
But the biggest obstacle of all to keeping an efficient lookout is allowing oneself to be distracted. The MAIB sees it over and over again. It could be paperwork, taking too long to put a fix on the chart or writing up the log. Dealing with the GMDSS can be a major problem, as can sorting out a defect or the investigation of an alarm. Visitors to the bridge, while often welcome and sometimes very helpful, can be a major distraction. And there are many other events that can severely interfere with this most important of all tasks at sea. The list is seemingly endless; a visit to the heads, the
prolonged brew up of a cup of coffee at the aft end of the bridge, filling in the garbage book, or even, would you believe, a requirement to conduct rounds in the engine room!
Of course there are distractions, but the important thing is to manage them. If it is busy out there, set your priorities and do not allow the distractions to take over. If they do and something goes wrong, life could become very uncomfortable indeed.
Two pairs of eyes are better than one when heavy traffic exists, visibility reduces or it is dark. Notwithstanding the clear directive to have an additional lookout at night, there is very clear evidence to indicate that some ships do not comply. This failure to appoint a lookout is a prime reason for a number of accidents each year. Accidents also tend to occur when one person on the bridge is overwhelmed by having to deal with several things at once in a busy shipping lane.
A rather curious feature of some accident investigations is the number of times an officer of the watch has dispensed with the rating on lookout duty. The reasons vary, but sending him below to get a cup of tea is often the prelude to an accident. Sometimes these absences can be very long. Keeping a lookout can be fairly tedious when there is nothing to look at but an empty horizon for days on end. It is slightly different when you are very tired, in a busy shipping lane and are making your way past sandbanks and other obstacles. The fact remains, however, that all your shipmates, let alone the owner, are relying on you to do a responsible job well. It is all too easy to let other things get in the way and prevent you from maintaining that good lookout.
Guidance from your company and the master is one thing, as is advice in a Safety Digest, but the penalties of failing to keep a good lookout in 2002 can be very severe indeed. Don't let it happen. Keep a good and efficient lookout - at all times.
Reproduced by kind permission of the Marine Accident Investigation Branch. Originally published in MAIB Safety Digest 1/2002.
www.maib.dft.gov.uk
