The dogs are usually prepared by no food for several hours, limited water, and and some Benadyl. That combination, a scratch under the chin, and the steady "purr"
of the Lycoshaker usually puts them right out. A good run and potty break is a really good idea before the flight. Once settled in, the dogs have never moved, unless it is to pop their heads up after landing. Yesterday, Wanda and BC did not move at all until after we had shut down and put the RV back in the barn.
I have an old moving blanket as the floor mat in the RV in case there are any accidents