When sizing an anchor or anchor rode, it’s useful to have starting point and to think of the whole system. This is a table developed by American Boat and Yacht Council (ABYC) to approximate the expected load on the anchor and the anchor rode for given wind speed and boat length. The complete table appears in Section H-40 of ABYC’s

Standards and Technical Reports for Small Craft

      available at abycinc.org.

The ABYC Horizontal Working Load (lbs) Table

Wind
Speed
(Knots)
Anchor Name
Boat Length – Feet
20 25 30 35 40 50 60
15 Lunch Hook 90 125 175 225 300 400 500
30 Working 360 490 700 900 1200 1600 2000
42 Storm 500 720 1400 1800 2400 3200 4000
60 Violent Storm 980 1440 2800 3600 4800 6400 8000

How do you intend to use your boat? Do you sail only on calm days with fair weather (Lunch Hook) or are you outfitting for an adventure (Storm) where you might be exposed to hazardous weather at anchor? For example, if you are outfitting a 35 foot boat for you should size the working rode and anchor to safely handle loads up to 1,800lbs if planning a cruising adventure, but the same margin of safety is not necessary if operating day trips from the safety of a marina.

ANCHOR SIZING:

When making sizing recommendations for a working anchor we are generally referring to the needs of a cruising boat spending most of its time on anchor, in doing so we try to envelope high sustained winds (40 kts) and assume poor holding conditions (low viscosity bottoms). Some may think these recommendations to be too conservative especially when compared to sizing tables from other manufacturers. Companies often make claims of superior anchor efficiency, stating that their small anchor X will outperform a much heavier anchor from their competitors and often use sizing charts as a marketing tool to that end, recommending anchors and anchor systems that are dangerously undersized for their intended use. Comparing surface area can be a good judge for potential holding capability. Our anchor sizing recommendations are presented in the table below and are divided in three categories: Lunch Anchor category is recommended for lighter use, expected winds under 25 knots, working anchor for winds under 40 knots and finally, storm anchor recommendations are intended for winds up to 60 knots. These recommendations are made assuming the worse case scenario, a poor holding bottom and thus may seem conservative but we believe are accurate.

ANCHOR SIZING GUIDE

Imperial