Propeller Calculator, Crouch's Calculator

Optimizing the performance of Boston Whaler boats
jimh
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Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
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Propeller Calculator, Crouch's Calculator

Postby jimh » Sat Oct 17, 2015 9:52 am

The two very useful performance-related calculators, the Propeller Calculator and Crouch's Calculator, are at this moment no longer available due to the move of the website to a new host. I am particularly fond of both of those calculators and will be making an effort to get them working again. While there are many alternative calculators available for the propeller calculations, the Crouch's Calculator was unique.

jimh
Posts: 3725
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Propeller Calculator, Crouch's Calculator

Postby jimh » Mon Mar 28, 2016 7:09 pm

I have not yet been able to restore the old Propeller Calculator that was available for years here on CONTINUOUSWAVE.COM. For an alternative propeller calculator, I recommend the very nice propeller calculator implemented at MERCURYRACING.COM. See

http://www.mercuryracing.com/prop-slip-calculator/

The above calculator is very versatile and the presentation is excellent. I recommend using this calculator until I can get our old one working again.

jimh
Posts: 3725
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: Propeller Calculator, Crouch's Calculator

Postby jimh » Sun Oct 23, 2016 8:36 am

An alternative to the Crouch's Calculator that was available here has been found at

http://www.go-fast.com/boat_speed_predictions.htm

Although the above page attributes this analysis to Mercury Marine, the method is identical to Crouch's analysis. The basis for Crouch's Calculator was the observation that boat speed is proportional to the power-to-weight ratio to the 0.5 exponent times a constant that was scaled for the type of moderate v-hull planing boat being analyzed. For a typical Boston Whaler hull the hull factor of 180 can be used to get a reasonable estimate of hull speed potential.