Dead Reckoning - the basics

Here at Penzance Sailing Club our active Training Group comprises of volunteers with a variety of experiences and qualifications.
The main aims of our Training Group is to encourage people in West Cornwall to take up sailing, enjoy the experience and be safe on the water.
The content of these videos is put together in good faith and is constantly evolving. It is possible that errors exist within this content.
Watching this content is not a substitute for completing a RYA Shorebased course or similar.

[joshuaespinoza]

Tell your kids " put down those cell phones and pickup a ruler and compass." Love these videos. Thank you

[DisabledPrepper]

Fantastic work. I am sharing this with friends. I would love to make such videos but have speech difficulties as well. Keep up the good work. Very clear, succinct and well presented. Excellent job! Thank you. Warm regards.

[michaelsolis]

So can anyone tell me the amount of stress one goes thru while doing this mid flight. I havent flown yet but I can Imagine this is extremely difficult

[jamesbaxter]

I see land and sea on a screen. I am looking to know how you plot a couse. Like the Pannama canal to Australia, stopping at some of the islands. Can you point to a place (S) so as you go. You know where you are going. Maybe time to get there. Thanks

[CheersWarren]

I’m surprised at all the decision of conversion to true north. I understand the ultimate accuracy argument but we always just use magnetic for everything. Way simpler. Compass reads true, true is on chart and the variation changes so little it does not matter. We only had parallel rulers so after we had made our best guess at the course sailed ( to nearest 5 deg) we would walk that course from the compass rose magnetic ring to the last position we had plotted with DR or confirmed another way. If we felt like getting really fancy we would add the compass deviation but it was never more than 1-1/2 degs so not of much consequence.
Much more important was to add the off set for the tidal current to the course.
Thanks for posting about DR, still an important simple way to navigate.
Cheers Warren

[malcolmhowe]

Would you not also compensate for tide and leeway? 6.5Nm is presumably measured via the log, which is distance through the water, but not over the ground.

[Capt.Safety]

My question how do you know how far you've traveled in a set time?

[clarenceleblanc]

The term comes from deduced reckoning hence ded reckoning, not dead reckoning. Also, if I remember correctly from my flying ground courses on navigation, we were taught how to add or substract from magnetic to true heading with the following sentence: East is least, west is best. So a west correction would require an addition, not a substraction. Hey, but I might be wrong on both. Look it up.

[sinancoskun]

sir good sir i wish i found you a few days ago so maybe i could just asked you if you could show us how to do runnig fix i have my last exam tomorrow i hope i will pass... but if you could post runnig fix one day that would be awesome thank you already

[jsmorrow]

Why do you subtract variation besides adding?

[evs]

What if you drift off course and you find that you haven't been following the set heading?

[Taz-Alba]

could this method work in aviation's dead reckoning?

[MrVenci]

Not bad! it's true but only if this variation is for the year of sailing. And you didn't mention the deviation

[kuantang]

Where can I buy you now use Parallel Rulers.
thank you!

[tobyque]

impressive! but why is this method obsolete now?

[GaskellleoCinema]

Why do you convert to ºT instead of doing the whole problem in magnetic?

[CruiserlifestyleBlogspot]

Why not just plot magnetic and use the variation compass on the chart?

[billybeerman]

Wrong! When variation is West he supposed to add to get True course. He subtracted so now he is 14 deg. off!
"West is best" you add, "East is least" you subtract.

[stenya]

West is best, so you should add 7degrees

[kei]

Good tutorial but I think it would be nicer if you minimize your tongue clicking. :)