IB Designs,USA signal flags are 8″ x 8″ because we wanted to have them at a size that people could use for banners and be able to spell words. The below picture shows a signal flag being hoisted and is one of the largest one. Since I like to use Paint Shop Pro I put the letter “P” of our own signal flags in the picture just to give you an idea of how huge the flags are that he is hoisting. The letter “P” and the “C” are probably size 14 in the Signal Flag Alphabet.
After researching on the internet the common sizes are as follows:
- No. 0- 1′ x 1′
- No. 2- 1.5′ x 2′
- No. 3- 2′ x 2′
- No. 7- 3′ x 3′
- No. 10- 4′ x 4′
- No. 14- 4′ x 6′
Although the above numbers are common now throughout history the signal flags have varied in size. Both in 1935 and 1963 the signal flags were slightly smaller. An example is that the number 1 size is now 1′ x 1′ but earlier it was 9″ x 12″. In the long history it seems to me that they varied by what the manufacturer decided to make them.