On 25 June, 13:28, "Dave Liquorice"
wrote:

I still feel that a properly made 15' timber gate is not a problem.

This gate is several years old and hasn't dropped at all,

Dropping isn't the problem, as you have the height of the gate to work
with for triangulating it with bracing (like I said before,
structurally a gate is a triangle, not a rectangle). The problem
you'll encounter first and most awkwardly is horizontal flexing when
opening or closing, even some helical twisting, as there isn't enough
thickness in the gate to brace it easily.