Yacht lengths

Large pleasure craft (or yachts) for commercial use are eligible to the RIF if the hull length (LH in French) is equal to 15 meters or above.

Hull length

The hull length is defined as the measurement of the ship length in accordance with the EN ISO 8666 standard:

"Hull length should be measured according to the figure above, with one plane touching the foremost part of the boat and the other touching the rearmost part. This length includes all structural and integral parts of the boat, such as wooden, plastic or metal fore and aft sections, bulwarks and deck/hull joints. This length excludes removable parts that can be detached non-destructively, without affecting the structural integrity of the boat (e.g. spars, bowsprits, pulpits, bow fittings, rudders, outboard motor chairs, propulsion bases, diving and reboarding platforms, fender strips and fender flanges. This length also includes detachable parts of the hull that act as hydrostatic or hydrodynamic support when the boat is idle or underway.”

Reference length

The reference length (LR in French) means 96 % of the total length on a waterline at 85 % of the least moulded depth measured from the top of the keel, or the length from the foreside of the stem to the axis of the rudder stock on that waterline, if that be greater. Where the stem contour is concave above the waterline at 85 % of the least moulded depth, both the forward terminal of the total length and the foreside of the stem respectively shall be taken at the vertical projection to that waterline of the after most point of the stem contour (above that waterline). In ships designed with a rake of keel the waterline on which this length is measured shall be parallel to the designed waterline.

Why is the reference length important? It determines whether the yacht is required to be registered with an authorized classification society (SCH). In accordance with Article 42-5 of the decree n ° 84-810 of August 30, 1984 on the safety of life at sea, pollution prevention, safety and social certification of ships:

• "any new or foreign-acquired ship with a reference length of 24 meters or above, […] independently of its particulars, excepted for pleasure craft for personal use, historic sailing ships, racing ships and experimental ships, shall be assigned the first class notation by an authorized classification society corresponding to its operation.
• This ship shall maintain compliance to the class conditions set for this first notation.
• An order of the Minister in charge of the sea defines, for each type of ship, the minimum areas covered by classification referred to as "first class notation”."

Thus, yachts with a reference length of 24 meters and above shall be recorded in the register of an authorized classification society.

Yacht lengths, summary

L’’: reference length (LR) which determines if the yacht is required to be registered with an SCH or not ;
L’: length between the fore and aft perpendiculars corresponding to the minimum depth (from which the reference length is measured) ;
Lh: hull length (LH) which determines if the yacht is eligible for RIF registration, the applicable reference system for the application (Division 241 or 242) and the competent commission for the application review (CRS or CCS).