Problems with IMS stability data

Hello there. Can somebody please enlighten me on the units used for IMS stability data ?

I'm am doing some indicative calculations for this boat: this boat (alternative link), an IMX 40. We're considering moving weight form inside the interior to the keel. I am now trying to make some quick calculations to find out how big the effect is on our stability.

Just to demonstrate, I take RM90, which is 41,6 . According to the IMS Rule book (rule 711 on page 47) this number is a righting moment divided by the degrees of heel. So if multiply that with 90 degrees, I arrive at a righting moment of 3744. I assume the units are Nm for now. Now divided by the sailing displacement (7574) times the acceleration constant of gravity (9,81) I arrive at the GZ value. The result is 0,05 m . Way to low of course for a cruiser/racer like an IMX-40 on its side. Now I could imagine that the moment is expressed in kNm, but that would be mean that the GZ is 50 m. Probably a bit of the mark as well ...... ;-)
So beyond that it would be guessing on my part .

So what is up here. What units does the IMS use for this number ? Or have I misinterpreted the definition ?

Also, can somebody confirm that RM / RMC is just a GM value. It seems so.

Thanks for any help.

 

If I'm not wrong, righting moments are in kg*m, not in Nm. Don't use "g".
Cheers.

 

Try it like this. Bold is mine.

 

Guillermo and rayk, thanks very much. That makes sense. Is there some guide where the units of the IMS data are listed ? It's not in the ORC Rule guide that I linked in my first post here.

 

Al other units are Kg., m, m2, sec/mile ore unitless ratio's.