A versatile and user friendly definition of the mast parameters

  • Layout

     SIMSPAR allows to define easily and quickly the most common type of layout including aft stayed rig, sweep spreader, staysail, self sustained rig, jumper..

     SIMSPAR provides as well the capability to modify and to customize the layout using interactive graphic control.

     Mast sections and cables properties


    SIMSPAR include a data base of commercial mechanical properties coming from various mast and rig providers.

     SIMSPAR allows the user to define and manage in the mechanical data base his own properties.

     Sailing conditions and loads


    SIMSPAR allows to define loads on sails and rig by various intuitive ways and for the most representative sailing conditions like dock tuning, regular sailing for various wind speed, extreme sailing close hauled with reef in the main, downwind breeze with spinnaker etc…

     Tuning cables and controls.


    SIMSPAR includes a powerful interactive interface to tune the cables of rig and various controls like vang, mast collar and mast foot. This allows to define pretensions specifications and to simulate effect of tuning modifications on the mast shape and the headstay sag.

     Mast data base

  •  The collection of the data for a mast ( geometry, mechanical properties, sailing conditions, tuning) can be saved in a file. This allow for example to create a public mast data base for the most popular dinghies and one design.


A complete description of the mast behaviour

SIMSPAR computes and displays after every modification of the model a complete set of data describing the behaviour of the mast.

 Values and graphic view of lateral and longitudinal deformation of the mast

  • Value of the headstay sag
  • Tension in cables of rigging, detection of slacked cables.
  • Buckling safety coefficients.
  • Compression in the mast tube.

A wide range of applications

  • Tuning of an existing mast

     SIMSPAR allows high level sailor to improve the tuning and to well understand the effect of available tuning and control on the bending of mast and on headstay sag.

     SIMSPAR allows mast manager of big boat to find quickly and easily safe and fair tuning of the mast which can saves consuming time and expansive trial sessions.

     Design of sails for an existing mast


    SIMSPAR provides to sail designer the data on longitudinal bending and headstay sag for various tuning and wind speed which helps him to design luff curve of mainsail and head sail.

     Include mast options inside a boat design process.


    SIMSPAR allows the naval architect and the boatyard design office to incorporate himself in the design loop various feasible mast solutions keeping the control on the outline, the loads and the weight.

     Optimise and ensure the design of mast.


    SIMSPAR provide to the mast designer all necessary structural data to find the best trade off for production or performance purpose.
More generally, SIMSPAR is the appropriate tool to create and share common knowledge inside the sailing technician community dealing with mast design and using.


  • Mast modelization

     SIMSPAR modelization of mast is based on FEM method. The FEM kernel of the method has been originally developed by HDS office since many years for this own mast design projects. Geometrical non-linear behaviour, global buckling, slacking of cables are included in the algorithm in order to predict with accuracy the deformation and the strength. The fully mast dedicated FEM kernel provides fast calculation which allows the user to get results instantaneously while mesh remains reasonable.

     Calculation of loads applied by sail on mast


    SIMSPAR calculation of loads applied by sail is based on studies carried out by CRAIN on sail stress and load by using his office developed FEM non-linear membrane code. Since those kinds of calculations remain too heavy and too sensitive to be included in a robust and fast software like SIMSPAR, only analytical formulas derived from FEM calculations are used to compute loads.

     Validity of the modelization (DOWNLOAD ARTICLE)


    Validity of SIMSPAR is proved by the HDS experience of hundredth of mast design for various application like IACC boats, Open 60’ monohulls& multihulls, maxi yachts, production boats etc…SIMSPAR has been also validated for several cases by using the reference commercial FEM code MSC NASTRAN ®. Last, real size rig measurements have been carried out for some mast.