Finding Your Way Without a Compass by Simon Phillips
Finding your way without a compass.
Alone at sea with a broken compass, fear not for help is at hand! Some navigational help by Simon Phillips – Associate Fellow of the Royal Institute of Navigators.
For a non sailor, fear is being on a boat in the first place. Just imagine being on a boat with no navigational compass / GPS or electronic charts. A complete nightmare it must be! How about simply turning the electronic navigation equipment off, like I do sometimes whilst mid Atlantic, it is total bliss! Peace from the continual beeping of electronic instruments! They aren’t needed in any case, for we have the sky which is full of stars, a warm breeze going to the Caribbean and plenty of time! You don’t need to be a sailor to gaze up at the heavens on a warm clear night with a pair of binoculars and wonder in awe! A good challenge and sense of real achievement for the navigator beckons! Sailing across the Atlantic or another expanse of water using traditional methods of navigating is much more satisfying than keeping the boat constantly on the blue line on the plotter screen!
As sailors’ we like to know where we are going! Making sure we have the right equipment onboard and knowing how to use it is a must! Not knowing how things work onboard and having them is worse than not having them to start with!
Well, our scenario – We have dropped our hand bearing compass overboard (a keel hauling offence!) and the fluid has leaked out of our main compass, a pretty dire position you might say. Well, it isn’t ideal I grant you, but with a few bits from the toolboxes and a few moments, we can find our way again!
What to do?!
Refilling your compass may be an easy solution, however you must first find the reason why the fluid leaked out in the first place. Find this and seal this would be the ideal solution. Then we can look at refilling the missing fluid.
What is the liquid inside the compass in any case?
It should be mineral oil or mineral spirits, although not mixed as they will separate!
I have heard and used other liquids which have sufficed for short periods of time. Liquids such as white spirit, pure alcohol may also work – although these may well have the affect of dissolving numbers / markings on the inside of the compass. Draining the compass now filled with alcohol for a hard earned drink is probably best avoided!
There is a drain hole in the compass for this very thing – refilling the compass. It would be advisable to find out what is in your compass beforehand, so you can keep some spare if it is ever needed.
If this all fails and we cannot repair our main compass, then we will have to resort to alternative methods –
Some ways of finding our way during the day with a few simple bits and pieces from the boat!
Let us start with checking the time on our watch, analogue watches are better in my opinion for a few reasons. One of these is that we can use this to find direction.
Assuming we are in the northern hemisphere;
- Point the hour hand at the sun
- See where 12 is
- Halve this angle between the hour hand and 12
- This new line is south.
Make your own compass.
Kit required to do this;
Needle, silk, magnet, cork, jar / cup of water, cling film.
Onboard should be a sail repair kit – useful for repairing sails and of course, and also for making a compass with! What we need from here is the needle. Alternatively, a small nail / panel pin will do.
Magnet – handy to have one onboard – for retrieving items dropped over the side, catching any metallic filings in the oil sump and for ‘charging’ our sail repair needle of course!
Silk – if you do not have a magnet onboard – this will help ‘charge’ the needle to make our compass.
Cork – so the needle can float in a jar / cup.
Making our new improvised ‘compass.’
Find the needle and magnet.
Hold the needle in one hand and the magnet in the other.
Put the North end of the magnet against the needle in the middle and rub it towards and off the point end of the needle.
Lift the magnet up and away from the needle and place it in the middle again.
Repeat this technique for the same half of the needle for approximately twenty times.
Turn the magnet over so you are using the South end and rub it from the middle to the ‘eye’ end of the needle approximately twenty times.
You have magnetized the needle just like a compass needle. Moving a magnet along the needle, this aligns the atoms inside the needle which then creates a small magnet.
Small pieces of cork are stuck on either end of the needle – be careful to not drop it, or the atoms will become randomly aligned and you need to restart the process!
Put the needle with cork into a jar / cup of water and it will slowly and gradually point north / south. The clingfilm is to stop any interference caused by any wind acting upon the needle turning in the water.
We will know which way north is, as the sun will be casting a shadow in this direction.
Lets see how we can find our way, at night, when our compass no longer points to the north. Doesn’t happen very often, however I have seen compasses loose their liquid, bulbs fail at night or something falling on it rendering it useless! And let’s face it, this only happens at 3am! Well, all is not lost – believe me. Some knowledge of the stars and a directional mind is all that is needed.
Here are a few basic tips on finding your way;
Finding North – We want to find The North Star – Polaris. This is the brightest star in Ursa Minor. By imagining a vertical line from Polaris to the horizon, this will give you north.
How to find it – We should know roughly where we are in terms of our Latitude, and we can use our latitude to look up into the sky at that same angle. As we are looking for Polaris, for example, if we are standing on the North Pole, Polaris will be directly above us – 90 degrees up. If we are in the Bay of Biscay area, approximately 45 degrees Latitude, then Polaris will be approximately 45 degrees from the horizon. This is no coincidence! The angle from the horizon to Polaris in the northern hemisphere will give us our Latitude too.
Finding East and West – Locate Orion in the sky. A large constellation, Orion, known as The Hunter in Greek Mythology. Once we have found Orion, we need to locate his belt, three bright stars in his middle. The star closest to his shield out of the three stars is called Mintaka, it is this which we are interested in.
How to find East or West – Watching Orion in the night sky, we can tell if it is rising or setting. Orion rises on his back – shield first, and sets on his front – shield first also. All rotating around Polaris. The star we are interested in here is Mintaka. This star is due East when Orion is rising, and will set due West when Orion is falling into the ocean.
Finding South – Look around until you see Scorpius in the night sky. Scorpius is on the opposite side of the sun as Orion – you will never see them in the sky at the same time! Scorpius is the largest constellation in the sky, looking rather like a Scorpion! The red giant star called Antares is at the Scorpion’s neck.
How to find South – As Scorpius moves across the sky rising and setting, it will tilt. Finding the three stars which make up the head and the three stars which make up the tail are important in finding South. When the three stars which make up either the head or the tail are vertical, then this is south.
These are some basic ways of finding our way onboard without a compass. Once a direction is found, an estimated direction can be steered throughout the journey. Bearing in mind that objects in the sky such as the sun will move 15 degrees every hour, a 90 degree course change can occur over a period of 6 hours! Therefore, checking our heading on a regular basis of around one hour intervals, we can pretty accurately keep our direction.
Seeing the nearest lighthouse at the coast should give us an indication of where we are!