Streaker PY number

Originally posted by JohnW Originally posted by tack'ho ... Now as Jim C so elequently puts it, <span style="font-weight: bold;">30 pints is realistically neither here nor there </span>... Remind me not to go drinking with Jim C!!!!  Doug & Captain Morgan - We are looking forward to Swanage regatta as always, expect a Garmin of Albacores to be there.

Awesome news!! I mean who could resist a town with seemingly more
pubs than houses.
Should hopefully be a group of boats from kent coming along. The
wilsonian 29ers and musto skiff and some others I think.

Originally posted by tack'ho The reason the Europe is 1139 is because it's sooooooo much better than a streaker

I want to defend my boat but I can't disagree with you. Only because I
wouldn't claim any boat is better than a europe.

I have streaker 1306 (?) in the garage awaiting a new rear bulkhead.  It is quite old, as you can tell by the number, so does not have the false floor and go faster stuff the newer boats do.  My guess is that the calculations for the py are more accurate for this type of boat rather than the new Butlers and Roosters.  Therefore the new boats are so much bandito they should be quarantined for suspected swine flu!

Presumably if I were smart enough I could use Dan's calculations to work out a py for the mogo.  As it is, I am too mathematically challenged (cse grade 2!)

Originally posted by Captain Morgan Originally posted by JohnW Doug & Captain Morgan - We are looking forward to Swanage regatta as always, expect a Garmin of Albacores to be there.   Goddamit!!! Don't even mention the bloody Albacore PY to me! The damned Albacore is the ONLY boat to sail in order to do well on handicap at Swanage. If I started sailing one I'd guess I'd be right at the top of the results table again! Along with more politics and much grumbling... Sorry, but I had to get that one off my chest. Hope to get a good turnout on 1st-2nd of August at Swanage (especially anyone in anything capable of thrashing the Albacores ).

Is that Bill McM. keeping you all in order?  Mind you he has had getting on for 70 years practice!  - Send him my regards.


Edited by JohnW

Originally posted by winging it dan, or anyone, does the py equation work in excel?  what does ^ mean, and how do we calculate RM?

Hi, its an excel spreadsheet that the plot is from - the formula I gave is straight out of the spreadsheet. "^" means raised to the power, i.e x^2 means x squared.

PM me if you want me the spreadsheet, although its probably a little baffling for someone who didn't write it.

Alternatively if you give me the length, beam on deck, sail area, weight ready to sail, I can assume a sailor weight and height and give you a steer if you like.

The RM calculation makes an assumption of righting lever by working out the distance of the sailor's CofG from edge of the deck, assuming some biomechanic stuff, and the assumed sailor height. (different oviously for trapezing and hiking) With the beam and assuming no heel we have the righting lever, with the sailor weight we have the righting moment.

Sorry for the waffle, but slightly more understandable than the righting lever equation out of the spreadsheet:

=IF(P88=1,((G88/2)*(COS(($B$2*PI()/180))))+($B$2*$B$3)+((O88 *$B$7)-(($B$12*O88)))*(COS((($B$10-$B$2)*(PI()/180))))+((O88 *$B$8)*(SIN(($B$11-$B$2)*(PI()/180)))),IF(P88=3,(((G88/2)*(C OS(($B$2*PI()/180))))+($B$2*$B$3)+(((O88*$B$9)))*(COS((($B$1 6-$B$2)*(PI()/180))))+((O88*$B$8)*(SIN(($B$17-$B$2)*(PI()/18 0)))))))

Dan