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Mercury’s Bravo Three Props Produce Improved Acceleration
FOND DU LAC, Wis. (Jan. 26, 2010) – Mercury Marine today announced the release of new versions of the 20, 21 and 22.5 pitch front propellers in Mercury's Bravo Three propeller lineup.

These new propellers provide improved performance, including a significant reduction in time to plane. The three-blade rear propeller continues in production unchanged.

“The lower-pitch front propellers in the Bravo Three line-up have been redesigned from top to bottom,” said product manager Dirk Bjornstad. “These changes result in better acceleration across the board with light and heavy loads.

“The differences are most pronounced on boats with slower acceleration times. We've seen up to 8 percent faster acceleration with the new four-blade front propeller in heavier applications."

A Bravo Three propeller set consists of two counter-rotating propellers on the same drive. The Generation II Bravo Three propellers feature a four-blade front and a three-blade rear while the Generation I Bravo Three propellers used a three-blade front and rear.

“Our engineers have made refinements to the rake profile to provide the kind of holding customers expect with a four-blade front propeller,” said Bjornstad. “The new low pitch propellers ensure the complete line of Generation II models will accelerate and hold better than their predecessors.” Production of the latest revision of the 20, 21 and 22.5 Brave Three series began Jan 22.

http://www.brunswick.com/news/newsstori ... 379118.php

Interesting; VP have had a 4 blade front prop and a 3 blade rear one on some of their DP drives for many years, but as far as I know only for diesel engined set ups. Stainess props are 3+3 also on the diesels. I wonder why VP don't use a 4 blade stainless prop? Cost maybe?

Graham