gary eudy wrote:
just because someone had good luck doing something stupid does not make it right
Two hobies stacked are top heavy four stacked are just dangerous to you and the traveling public
I'm inclined to agree with admiral gary on this one. Unless the boat box on that trailer is full of bricks, I would expect that trailer to be unstable (and the fact that it hasn't flipped yet does not make it anymore stable).
A quick google search shows that there is this thing called a Static Stability Factor used in assessing vehicle stability. It's a simple calculation relating track width, T (center to center wheel spacing) to the height of the CG, h... SSF=T/2h. The higher the SSF, the greater the vehicle stability. Your average passenger car has a SSF somewhere between 1.1 and 1.4.
I calculated the approximate SSF of my trailer with boat to be SSF=1.1. (T=5.5ft, h = 2.5ft). I would expect your average double stack to be somewhere around SSF=.8 .
For the triple stack +2 shown in the picture, I would estimate the CG to be at about 4.5 ft with the same track width. This means SSF=.61, so about twice as likely to roll over as a standard single Hobie trailer. Even if I'm off by 20%, I'd say that still puts that rig at scary
Just something to consider when you start piling boats on top of one another.