SELDÉN DEFINITIONS

 

THE RIG

FH

Forestay Height

Fractional rigs: From deck/coach roof where the mast base stands or where the mast enters the boat to where an extension of the forestay intersects the front of the mast.

Masthead rigs: From deck/coach roof where the mast stands or where the mast enters the boat to top end of mast extrusion.

CSH

Cutter Stay Height

From deck/coach roof where the mast stands or where the mast enters the boat to 
where cutterstay crosses the front of the mast.

P

Main sail luff space

From top edge of black band at boom level (top side of the boom aligned 90° to the mast) to lower edge of top black band.

BH

Boom Height 

From deck/coach roof where mast stands or where mast enters the boat to top edge of the black band at boom level (top side of the boom aligned 90° to the mast).

Q

Bury

From deck/coach roof where the mast enters the boat down to the surface where the mast base is fitted.

E

Main sail foot space

From aft edge of the mast to the forward edge of the boom’s black band.

S

Main sheet distance aft of mast 

From aft edge of the mast to the main sheet fitting in the boat. Main sheet attachments on mast may be denoted with S1, S2, S3 etc, positioned from aft face of the mast.

SPL

Spinnaker Pole Length
Note:Different rules state different definitions, the SPL varies slightly. Please see actual measure rule system.

J

Fore triangle base 

Horizontal distance from the intersection between forestay and deck to the mast section front at deck height level.

DH

Deck height

Centre of V1 chainplate pin hole / the surface where the tipcup chainplate is mounted to deck/coach roof where the mastbase stands or where the mast enters the boat.

WLH

Water Line Height 

Vertical distance from water line to deck/coach roof where the mast stands or where the mast enters the boat.

 

 Righting moment

RM30°

Righting Moment at 30 degrees

Static righting moment the boat creates at 30 degrees heel. 
IMS, IOR or other measuring rule data may be given. As well as a 30 degrees value from the designer of the boat.

 

The righting moment can be approximately estimated by Seldén if boat data are given as below. For the stated righting moment it shall be stated what’s included. Whether the stated righting moment is stated for a fully loaded and equipped boat or not and how many crew members sitting on rail taken into account. 

LOA

Length over all

The over all length of the yacht.

Beam

Max Beam

Maximum beam of the boat.
Draft Maximum draft of the boat.
Displacement The total weight of the boat, including ballast. 
Note: It shall be stated whether this value is for a loaded boat or not.

Ballast

Keel weight including bulb.

Bulb / Wing keel

Is the keel a classic conventional keel or is it a wing keel or bulb keel which most of modern boats are equipped with.