The Disadvantages of a Modified Full Keel

Steering Disadvantages

• Like a full keel, a modified full keel offers stability in bad weather. However, because the keel still runs the length of the boat, modified full keels are clumsy compared to a streamline fin keel. Unlike the fin keel, which has a smaller turning radius, a modified full keel requires more turning room and is less likely to be capable of making a quick, agile turn. Additionally, the modified full keel does not offer any additional agility while steering or maneuvering the boat in reverse.

Speed Disadvantages

• Cruising and hobby yachts are less likely to require speed as sporting or racing yachts do. Therefore, another disadvantage of the modified full keel is the reduction of speed at the cost of balance. Because a modified full keel increases the surface area, water resistance has a tendency to reduce the speed at which the boat can move. Additionally, modified full keels are not able to steer in reverse unless the boat is at a stable speed already.

Weathering

• While modified full keels are still used among boat hobbyists, they are not as easy to maneuver in bad weather. The increased surface area of the keel results in a greater amount of lateral resistance than a fin keel, which means that during severe weather, there is more resistance to turning and steering. A modified keel can endure bad weather; however, it does take more time to accomplish turning and maneuverability during such types of weather.

Considerations

• Double keels and fin keels are alternatives to full and modified full keels as they offer better handling and speed in both regular and severe weather conditions. When purchasing a boat, consider if the boat is going to be used for pleasure or for sport. Generally, boaters who are more interested in sharp turning speed and ease of handling choose a fin keel over a modified full keel.