I just finished sailing lessons and put my newly acquired 21' american fiberglass boat in the water. After tuning and rigging we gave it a try last night. After being blown downwind for awhile we realized we forgot to lower the vertically retractable keel. I winched the cable all the way down and we heard the keel knocking back and forth with the waves. I'm not sure if this is normal or if something is wrong. My wife was quite nervous and we motored back to the dock. I am going to take a swim and look at it today. It didn't seem like there was any kind of locking mechanism. Am I missing something or is this the way these boats are supposed to be?