Max mast height at NORMAL POOLS on the Tenn-Tom from Kentucky Lake to Mobile is 52 feet. There is one
lift bridge on the Tennessee that is higher than 52 when lifted. The rest to Pickwick are above 52.
I took a CaboRico 40 down with Mast up in 2007 and it was just below 52 feet. It was close on a couple of bridges - calculated at 2 inches, but no contact.
In 2013/14 when we went to
Florida and returned (mast down on our H356) floods on the lower part of the Tenn-Tom raised the pool levels as much as 15 feet. If close to 52 feet you have to watch the water levels very carefully. I have a spreadsheet I will share with you that you can enter your mast information into, then update off
internet with pool information and see how close your mast will be. If you go in the late fall say mid to late October, then typically the pool levels are normal and we don't typically see floods, but there is that possibility so you might get stuck for a few days in between locks. There are 13 from Lighthouse Landing to Mobile.
We are at Lighthouse Landing at Tennessee River mile 24, just above Kentucky Dam and they can re-step your mast if you are short enough. You can do some
motor sailing and sail for a day on the upper Kentucky Lake, but none below there except
motor sailing. If you are low enough and have
radar on the mast that is a good reason to put it back up. You need radar some times due to
fog unless you want to have limited travel time. There are times when you will be ok early morning and after an hour or so,
fog will return and the visibility is almost zero. Once on the Tenn-Tom sailing or motor sailing won't help you because the locks congregate
boats so if you get to a lock 20 minutes before the pack, you will have to wait for the slowest boat before they will operate the lock.