Posted: Feb 05, 2018 - 02:19 PM
There are many, many variables to that question. Which A are we talking about? What weather conditions? I would say a modern A isn't going to suffer much of a performance loss until you are at 200 lbs or so. Something like a Boyer Flyer or Nacra A2 may take a hit at about 180lbs.
In 20 kts of breeze, 250 lbs on the wire is going to be a rocketship upwind. Downwind, you probably wouldn't be trapping but you'd also have healthy margin to push driving from the tramp.
The other factor is mobility. A's are demanding boats to sail as they are powered up, lightweight boats that move in the slightest breath of wind. At 250 lbs you weigh nearly 100 lbs more than the boat, so its pretty easy to pull the boat over on top of you if sailing in low to mid range puffy conditions and you need to be quick on your feet to stop it.
The last issue is rig, you would want a stiff mast and sail cut designed for a heavy sailor.
Will you be competitive in a competitive A Cat fleet? Probably not, but I would venture to say boat speed won't be your issue in breeze, and most folks will suffer defeat in a relatively competitive A fleet as there are a lot of heavy hitters in the class, and it seems more getting involved every day.