This article is from the Piano Purchase and Maintenance FAQ, by Isako Hoshino email@example.com with numerous contributions by others.
For cross-country move, try having the following conditions
added to your moving contract.
(1) The piano will not be transferred at shipping
terminals across the country, and will not be
unloaded off the 18-wheeler trailer once it has been
initially loaded on
(2) The piano will be blanket wrapped, and strapped to
the side of the trailer
(3) The trailer will be one of the "computer air-ride"
trailers that maintain a constant/controlled air
environment. (There exists such trailers which are
designed to handle computer and other instruments)
(4) Insure the piano for its full replacement value