Cal 40 Sailing

Rudder Repair & Upgrade

Cal40 Class Association • Technical & Performance Overview

Performance Upgrade

Carl Schumacher Rudder Replacement for C40


When Bill Lapworth originally designed the Cal 40, his deep, high-aspect ratio, balanced spade rudder revolutionized production yacht design. However, after decades of hard ocean racing and heavy offshore cruising, many original rudder stocks suffer from corrosion, core moisture delamination, or excessive weather helm when driving hard off the wind.

To address control issues in heavy following seas, a group of twenty Cal 40 owners joined together to commission renowned naval architect Carl Schumacher to engineer a modern, high-performance replacement rudder.

“The result was a balanced elliptical rudder with a surface area similar to the original Lapworth blade, but far better balanced to minimize weather helm—especially when reaching and surfing in heavy air.”

Key Benefits of the Schumacher Blade

Reduced Helm Effort

By moving the center of effort relative to the rudder stock, the balance significantly decreases tiller loads, making high-speed ocean driving and autopilot operation far smoother.

Spin-Out & Broach Prevention

The modern foil profile maintains attached flow at higher angles of attack, delaying stalling and maintaining positive steering control when surfing down large ocean swells.

Structural Integrity

Replacing a 40+ year old stainless post and foam-filled core provides essential peace of mind prior to offshore events such as the Transpac or Pacific Cup.

Reference Articles & Historical Resources

For additional background on the development of the Cal 40 and its retrofitted rudder options, explore the following resources: