Dinghies and Drag - SailNet Community
LinkBack Thread Tools
post #1 of 1 Old 04-09-2001 Thread Starter
Contributing Author
Join Date: Jan 2000
Posts: 251
Thanks: 0
Thanked 4 Times in 3 Posts
Rep Power: 16
Dinghies and Drag

How can I reduce drag from hull and foils in a dinghy?

Dan Dickison responds:

You're not alone in your quest for reducing drag. In fact this is an ongoing pursuit for any serious racing sailor. The first way to reduce drag is to reduce wetted surface area. By that I don't mean reconfiguring the hull of your boat, but by getting as much of it out of the water as you can. This involves lightening the load carried in the boat and adjusting your own body weight while sailing. Here's an example: I race on a 28-foot boat called an E-Scow. One of the keys to performance in this boat is to achieve the proper heel angle so that we have a minimum amount of wetted surface area (read drag). Of course we carry the minimum amount of gear necessary (life jackets, bucket, etc.), but we're always trying to be cognizant of how much heel we have when sailing.

The other way to have an impact on drag is to make sure that your hull and appendages are as fair and smooth as possible. Since you sail a dinghy, I'm going to assume that you don't have any bottom paint on your boat. What you need to do is to make sure that the hull is as smooth as possible from the bow aft at least halfway to the transom. Aft of that, the flow over the hull is so turbulent that spending additional time smoothing it won't have much effect. Do the same thing with your blades (rudder and centerboard). I recently raced at the Acura SORC in Miami, and one of the top boats there (a boat that is drysailed and therefore has no bottom paint) had a common lubricant applied to its hull to combat drag. I don't like the negative consequences for the environment that this application carries, but you have to admit it is a novel approach. I've even heard of some dry-sailed boats using teflon wax on the hull and blades.

A source of ours who specializes in bottom preparation for racing says that he's gotten great results with high-grit sandpaper. That's high grit as in 1,000-grit paper. My experience is limited to 600-grit paper, but I'd recommend you try the 1,000-grit route and see how that works. Best of luck.



Dan Dickison is offline  
Closed Thread

Quick Reply

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Posting Rules  
You may not post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is Off
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome