Hi 
I'm a university student, Im in my 3rd year and im doing a project on designing a landyacht.
I need some help with the sails part 
However I'm very new to how sails work and only know the simple fundementals of sails.
I have to do some calculations on the velocity of a land yacht, just some rough ones to start with what I don't know is how I can calculate how much force the sail generates from a given wind speed, and once I calculate this forward force, how do I calculate the velocity of the land yacht, given the land yacht drag and wheel drag 
I would really appriciate it, if someone could shed some light on the subject so my question is how do I calculate the speed of the land yacht?
Thank you in advance!
So would we! There are a large number of variables involved like:-
yacht weight(including pilot), stiffness/flexibility of mast, wind direction, wind density, elevation above sea level(affects wind density),wheel size, tyre pressure, sailing surface- salt, sand, clay or carpark just to name a few.
If you do discover a formula, PLEASE let us know
Hi RED01,
Good on yer! You come all this way just to find out that you have a perfectly good Sail Maker in your own country[}:)]
I have just been in contact with John of http://www.sailrepair.co.uk/shopoffers.htm
info@sailrepair.co.uk
He has given me some really good advice.
I do not know where he is nor yourself, regarding County location but contact him and mention Ron Williams .Tassie
Go research your project.
Ron W
Go here to see a Land Yacht video etc.
www.seabreeze.com.au/forums/Land-Yacht-Sailing/Construction/Just-working-out-a-build/?page=4
People in the sport over the years haven't worried to much about measurements of strength and forces etc., most of the design info comes from trial and error like "at what point it bends / breaks then make it just a bit stronger"
With sails and forces it can be a VERY variable thing and would be hard to measure, and lets assume you can actually get some figures what then, how does it relate to the real world?
The only yacht that might have had tests and forces done on it would be the Blokart or perhaps some of the other production line produced yachts.
Giz'
Who was that Dublahumpty Wheel barra fella that you guys were talking about a month back. You know the one that tested Sails in a Wind Tunnel affair and wrote a book. That may be of some use RED 01.
Ron
There now Gizmo, That wasn't so hard. Was it
[}:)]
You have been very cooperative with the Gentleman
Ron
