Sail Trim Quiz

Tag: sails rigging

Test your knowledge of sail trim:


Take this simple test to determine your sail trim level of knowledge

Thanks to Don Guillett for this quiz. The purpose of this quiz is to test your sail trim knowledge. There are no trick questions. The sail trim controls outlined in the quiz are standard on most mast head rig boats and their function should be understood by every sailboat owner. Here's the situation - you are sailing to windward in 5 to 15 knots of wind in a relatively small choppy seas. What general mainsail and jib settings would you use to obtain optimum performance from your Catalina 30? Assume your the skipper issuing sail trim instructions to your crew. You have 2 minutes to issue your instructions. It is important that as skipper that you know WHY a particular sail trim adjustment is necessary. If you do not have a cunningham, just skip that question. 




1) Traveler - where is it placed on the track?


2) Mainsheet - how much tension and why?


3) Halyard - how much tension and why?


4) Outhaul - how much tension and why?


5) Cunningham - how much tension? I prefer the cunnigham over the

halyard as it is easier for me to adjust than the halyard.

6) Boom Vang - how much tension?

7) Draft Depth - what %?

8) Draft Position - What position on the boom? (40% to 60%)

9) Telltales - what are the leech and center sail telltales suppose to

be doing?

10) Mast Bend - how much?

11) Batten - Where should the top batten be pointing?

12) Leech line - how much tension?

13) Crew Position - what side and where on the boat?

14) Twist - how much?



1) Halyard - how much tension?

2) Fairlead - inboard or outboard and where would you position them

(forward or aft?)

3) Sail Position - where in relation to the spreader?

4) Head stay Sag - how much tension?









Answers below:



The following answers where collectively obtained from authors such as Dennis Conners, Gary Jobson, North Sails et al and over 50 various sailing magazine writers. They are general in nature and designed to get you into the ball park so you can fine tune your boat from that point. 


MAINSAIL 1) Traveler - close to center


2) Mainsheet - moderate tension, which provide moderate twist.


3) Halyard - tight which moves the draft depth to almost flat


4) Outhaul - fully tight to obtain a flatter sail

5) Cunnigham - moderate tension with some luff wrinkles

6) Boom Vang - snug tension

7) Draft Depth - 12% to 13%

8) Draft Position - 50%

9) Telltales - ALL streaming but the top can "just" stall

10) Mast Bend - moderate tension

11) Battens - top not more than 10% to 20% to leeward

12) Leech line - moderately loose

13) Crew Position - windward / forward

14) Twist - moderate


1) Halyard - Moderate tension with very few wrinkles

2) Fairlead - inboard and normal (middle) position. Telltales should

break evenly from top to bottom

3) Sail Position - on the spreader

4) Head Stay Sag - medium tension. Sag adds power.


So, how did you do? I hope you had fun with the quiz and more importantly were able to honestly asses your sail trim level of knowledge. If you did not answer all the questions correctly don't feel bad as only 25% of the sailors worldwide could answer all correctly in 2 minutes. If you don't believe me, print the quiz and ask these questions to some of your sailing friends and see how they do. Some things should jump out at you after taking this test. Do you understand all the terms such as draft depth, draft position and twist? Understanding these terms is critical to understanding sail trim. If you do not have a complete understanding of draft depth, draft position, twist and angle of attack, sail trim will never make any sense to you. If you do understand those element, this quiz is a snap.







I call those items "The 4 Elements Of Sail Trim". Do you know what happens to each of the 4 elements of sail trim when you ease or trim the sail trim controls for the mainsail and jib? If you don't know what happens, how can you effectively adjust your jib and mainsail? The answer is obvious - you can't. So where does a beginner to intermediate sailor go to get these answers. The answer is simple - check out my web site and review my book "The sail Trim Users Guide" and its companion "The sail Trim Chart". Both are sold with a money back guarantee. If you are not completely satisfied, I'll refund your money and you can keep the products.


Don Guillett





Share It!

Login required to comment
Be the first to comment