WinDesign VPP

The VPP suite of software that the Wolfson Unit is offering is its latest release of the industry standard WinDesign4 VPP.

Please email us with your VPP requirements.


1. What is the definition of 'K-R Sep' found in the Flotation dialog, Keel group box ?
K-R separation is the mean distance between the leading edge of the keel and leading edge of the rudder.

2. I cannot run older .vpp files
The link with the underlying opsets (.ops) file may have been lost. Open the .vpp file and resave it to generate the opsets file, then run it again.

3. Does the program have a simplified input functionality?
Yes, the flotation parameters may be input directly in the VPP if the lines are not available.

4. How do I input a long keel hulform in the VPP?
The J Class option fundamentals are described in our paper 'Development of a Vpp based rating for J-Class Yachts'. In summary:

LPP - use the long keel option, this means that the entire hull, integrated keel and rudder are all one geometry, so no need to define keel and rudder.









VPP - in the Modelling page of the Flotation dialog, use the following settings

Otherwise you should be able to use the VPP in the usual way.

5. What coordinate system are the aero coefficients Cl and Cd referred to?
Apparent wind axes.

6. Is the basis area for Clx and Cdp the VPP's calculated sail area of the respective sail?
Yes, but the user can change this sail area input.

7. What does the Cd2 term account for?
This is Quadratic profile drag, which is multiplier applied to Cl2 but is independent of effective span, i.e. actual span does not change the influence of this (~Total sail Drag= parasite drag + quadratic profile drag + induced drag).

Release notes: 

Release changes are cumulative.

Release Notes for WinDesign4 Version:

  • The AeroTypes have been improved.
  • The user interface has been improved.

Release Notes for WinDesign4 Version:

  • HASP hardware lock protection and Windows 10 compliance.
  • Microsoft HTML Help (.chm) manual.