The Answers to the Quiz
1. Which side should you pass this buoy?
This is a starboard lateral mark. The correct side you should pass it on depends on which way you are going relative to the nearest port. Which way round the buoys are placed is set by the Direction of Buoyage. In the UK and Europe the direction of buoyage is from the sea into the harbour.
So if you are approaching the harbour, you would leave this to starboard (the right). If you are going away from the harbour, then you leave it to port (the left).
It´s not really a fair question as you actually need more information before you can answer it. We pitched it this way to remind you that in real life, making assuptions on limited information is dangerous at sea.
If you could see the rest of the lateral marker buoys you would know exactly where the channel, but what if you are making a passage in thick fog? In low visibility, knowing your position on a chart is the key to making the right decision on which side to pass this mark.
2. What does this mean?
It is an East cardinal buoy recognised by the arrangement of the triangles on the top and its coloured banding. This Buoy is telling you to keep to the East as there is danger to the West. For more information of Cardinals, click here
Once again, you need a chart to tell if the warning matters to you. It may be guarding shallow water such as a shingle bank but the LAT depth may still be 2 or 3 metres – plenty for a motor boat.
3. What and where is the danger?
These are the lights seen from the starboard side of a ship travelling from the left to the right. It is making way – that is moving under power.
The green light and the two highest white lights are the ships navigation lights, and the fact that there are two lights arranged as they are mean it is probably over 50m in length.
The two lower, all-round lights are the problem. They indicate this boat, itself over 50m long, is towing another boat that is over 200m long. So the danger is to the left and you need to avoid the tow cable between them.
4. Good day for boating?
This is a surface pressure chart. The lines join places of equal pressure and are just like contour lines that join places of equal height on a map. On a map, the closer these lines are together, the steeper the gradient. On a surface pressure chart, the closer these lines are together the stronger the wind.
This chart shows an area of low pressure centred across the UK. The average pressure is 1013mb. The low on this example is 980mb and the lines near the south coast are very close together. There is also an occluded front curling around (the purple line).
So, unless you are a masochist, this is not a good day for boating. The south coast will be suffering from strong westerly winds (possibly gale force), grey skies with some rain.
5. When should I not choose to round the headland marked by diamond A?
The purple diamond with a letter in it – in this case A – is a style of mark found on a maritime chart. This one was just off a headland. Each diamond with a letter has a corresponding table. In this question, the block has tables for tidal diamonds A,B, and C.
The table has three columns. The first shows the Bearing (Direction) of the tidal flow at each hour either side of high water (High tide). The second shows the speed of the tidal flow past the headland in knots per hour at spring tides (large tidal range between low and high - more water means faster flows). The third column shows the speed at neap tides (small tidal range meaning slower flows).
This table tells us that during a spring tide, the water is flowing around the headland at 2.6 and 2.3 knots, three hours and two hours before high tide respectively. Add an opposing strong wind and you can expect the thrills of a very bumpy ride as you round the headland.
In contrast, if we waited to round the headland at high tide, the water would only be flowing at 0.1 knots. An indication you would enjoy a peaceful passage on calmer waters as you round the headland.
Please note: the high tide time the table is using is the time for the reference port. On this table, the reference is Portsmouth. So to plan your journey you would need to know the high tide time for Portsmouth on that day.
6. What is a marine mobile service identity? Where is channel ‘M’?
An MMSI number is a unique number issued by OFFcom to a registered ship´s radio.
It can be thought of as the marine equivalent of a unique telephone number.
The MMSI number can be used to call other boats, stations and the Coastguard directly instead of using voice over channel 16.
A call made using this method, alerts only the intended receiving radio. When the call is accepted by the receiving radio, information is passed electronically so it automatically selects the channel specified by the caller.
It is worth remembering that from this point on, communication continues by voice over the pre-selected channel. So it is not a private call and you should therefore observe correct radio protocol at all times.
Channel M, as it is often called, is normally channel M1, number 37a. When marine radio was first introduced, the band allocated was only wide enough for 28 channels. As marine receivers and transmitters got better, it became possible to subdivide bandwidth and get twice as many channels. Instead of numbering them from 28 on upwards to 56, the decision was taken to number the additional channels from 60. So that gives us channels numbered 0-28, 60-88. There were no channels within the original frequency range between 28 and 60. That is, until 37a was added for special purposes. This channels frequency does not lie within the original frequency range.
Now that we have even more sophisticated marine radio equipment available, you can expect further band designation changes in the neat future.
Season 2023/24
Season 2023/24
Call Will for all boat training requirements on
01202 836721
Bespoke Tuition to suit your requirements, can also include crew training on your boat.
Call Will to discuss on
01202 836721
Our Details:
Saltwater Experience
Bailey Bridge Marina,
10 Bailey Drive,
Christchurch,
Dorset BH23 2BN
Tel: 01202 836721
Principal: Will Eveleigh
Chief Instructor: Lloyd James
- Shorebased courses:
- Diesel maintenance
- VHF Radio course
