>>Don't the NAF-18s and the F-20s in Europe just have a small logo on the hulls? Do we need something on the sail?

The rules only require a small identifying logo near the clew of the mainsail and a measurement sticker near the beam on the inside of the hull. Most builder don't put F18 or F20 logo's on hulls or sails and often only use their own brand logo in the high part of the sail.

The two stickers are supplied with a valid measurement form.

Wouter