At least 70 ft, 75 is better
The mast is about 28 ft from base to head. If you have a turning block at the bottom (you pull UP on the halyard to raise the mainail) that's 56 feet of line. You need some slack for handling and cleating, so add six to ten feet more. If you take care of your halyards, they'll last at least ten years. You should cut a couple of feet off the shackle end of the halyard every couple of years so the same spots don't chafe on the sheaves. That's five to ten feet more. Your total now is somewhere between 67 ft and 76 ft. I'd go high. It's just nine more feet, which is still cheaper than completely replacing a 65 ft halyard in three to five years. Here's my Rule No. 1 for running rigging: A line that's a foot too long is a nuisance. A line that's a foot too short is useless. Happy sailing. Peter H23 "Raven"
