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Boston ASA 105
Coastal Navigation Course




3 Days

About the Course

Prerequisite: ASA 104 Bareboat Cruising

ASA 105 is a classroom based course that teaches students to apply the navigational theory and practices for safe navigation in coastal and inland waters. We practice charting and passage routing using compasses, parallel rules and dividers. Students learn the intricacies of tides and currents and how to adjust their projected courses to account for these differences. 

Topics Covered in ASA 105 - Coastal Navigation


Dead Reckoning and Estimated Positions

Learn how to apply the fundamental relationship between distance, speed and time in order to find an estimated position or when determining an ETA.

Taking Compass Fixes

Expand on ASA 104's teaching of taking two and three point fixes using a hand bearing compass and how to apply them to a navigational chart.

Calculating Set and Drift

How do we compensate for currents and the side-slipping motion, Leeway, from our own boat when dead reckoning? We teach how to compensate for set and drift so that you can be confident that you will not drift off course planning routes across tidal or current heavy areas.

Taking Running Fixes 

Learn how get a moderately accurate position using a fix off of a single object on the coast, sailing for a length of time and then taking a second fix from the same object. Running fixes are a crucial technique when sailing up and down the coast!

Converting courses and bearings between True, Magnetic and Compass North

We teach how to take a compass bearing, account for deviation and variation and plot it on a navigational chart according to True north.

And more!

We teach far beyond the basic ASA 105 curriculum and cover topics such as tides and currents,

danger bearings, electronic navigation instruments, important navigation publications, and much more!

Students will graduate the course with an American Sailing 105 Coastal Navigation Certification.

Frequently Asked Questions

Where is the ASA 105 held? 

ASA 105 is a classroom-only course held in our classroom in East Boston. It takes place over 2 consecutive weekends. 9am to 5pm on Saturday and Sunday, then 9am to 5pm again on the next Saturday.

How many students will be in the class?

We limit the number of students in the class to 6, in order to have room to spread out the large training charts and so that each student receives plenty of one on one attention from the instructor.

What do I need to bring?

Students will need to bring their own dividers and parallel rules or they can purchase them on the first day from us. First Reef Sailing will provide all other materials.

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