Sail number placement

[Ru88ell]

I've noted that Zephyr doesn't have her number on her mainsail. Since I intend to do the odd race I need to know where to stick them. Is there a stated, measured location for sail numbers?

[Dennis]

Hello Ru88ell

There does not seem to be a fixed position, the actual position seems to be at the whim of the sail manufacturer. If you look at the various photos on the Home Page and in The "Pictures and Albums" section you will see what I mean.

eg. Mike Brooke,s boat "Sea Badger ll" has the numbers just below the top batten, my boat "Mary Ann" has them just above the centre batten on the starboard side and just below the centre batten on the port side. The point I am making is that these two boats both have cream coloured Hyde sails but have the numbers in different positions.

I reckon as long as the numbers are clearly visible even when fully reefed (racing?) the precise position will not matter.

Cheers

Dennis

CC19 #100 Mary Ann

[Ru88ell]

Cheers Dennis. My current class has very strict rules regarding size and position of numbers. In the absence of anything formal, should The Webmaster come up with a definition?

[David Hudson]

Best practice for sail numbers per ISAF "Racing Rules of Sailing":

New rules 2002

The new 2002 rules, both for the IOM class and the RRS, take a completely new approach to sail numbers. A number of restrictions have been removed, only one new requirement has been added, and an easier set of specifications have been developed. Appendix G of the RRS now deals with sail identification, not the ICAR, and for radio sailing Appendix G is modified by rule E6 of Appendix E. Amongst other things, this approach now means that sail identification is an RRS issue, not a "measurement" issue, and your compliance with Appendix G as modified by E6 is now an issue that the Race Committee deals with at an event.

Recommended RRS E.6 revision

Keep an eye on the latest developments. Appendix G as modified by Appendix E.6 is problematic in the 2002 RRS, and rule changes have become necessary. ISAF-RSD have published a recommended change to E.6 on their Web site, and it is this that I describe below.
In summary, your sail numbers (and national letters, if any) should have a legibility "better than Helvetica". Numbers must be between and 100mm and 110mm in height. Their width, stroke, or radius of curvature is no longer specified. Such numbers would typically result from a sans-serif font rendered at between 390 and 420 points in size. The gap between adjacent digits or letters must be between 13mm and 23mm. National letters must be capital letters, between 60mm and 70mm high (230 to 270 points). Note that in order to obtain the right gap between numbers or letters, you will probably have to ensure that character spacing is set somewhat higher than the default value in your word processor, drawing package, or paint software. For the numbers, character spacing would be around 15%, and for the national letters around 25%, of the width of a space character. The gap between numbers on opposite sides of the sail must be at least 60mm, and at least 40 mm for letters. Remember that the starboard numbers or letters are placed higher than the port ones, remember that numbers and letters need to be all in the same colour, and remember to leave room for a "1" in front of your numbers. If space is limited, there is a set procedure to follow according to E.6, and note that smaller digits are only permitted as an absolute last resort. Numbers on the mainsail must be in the upper 75% of the sail, while the placement of numbers on the jib is not restricted. National letters are to be below the mainsail numbers. Finally, here is a simple test to check if your sail number in your favourite typeface is "clearer than Helvetica" -- make up your number in Helvetica, prop it next to your favourite, and then walk away until one of the numbers becomes unreadable. It had better be the Helvetica number.... (You don't have Helvetica? Arial is pretty similar.)
The IOM insignia is a 50mm diameter black circle, with a central vertical white bar 10mm wide by 35mm high.

The "kerning" problem

The spacing between national letters should be between 13 mm and 23 mm, and our sailors in ITA have a potential difficulty with theirs. If you think that the letters should have a "bounding box", and that the spacing between the letters should be measured as the space between the bounding boxes, you run into the "kerning" problem, as illustrated by the "T" and "A" in the first row. The bounding boxes are 13 mm apart, but the letters themselves are over 30 mm apart -- outside the rules.

My unofficial suggestion is to forget about bounding boxes and to measure the gap between the letters (and digits) from their nearest points. However, this is not a suggestion that receives universal support. It seems that the exact meaning of the word "nearest" will have to be established via a request for an interpretation to ISAF itself.

David

[Ru88ell]

I've just had sail numbers added to my main by Sanders Sails. I guess I should take a look at what they did. I guessed that a sailmaker should know..