I fly for Animal Rescue Flights (www.animalrescueflights.org) in my Aztec or the Mooney. Total of 9 dogs so far. The dogs have never had hearing protection. So far, the only complains I've gotten have been from rapid descents or turbulence, but so long as the flights are smooth and descents are in the 500-700 fpm range, they seem happy.

I have friends who use Mutt Muffs for their dogs and say the dogs love it. I would agree, it seems like a good idea.

Dogs are generally better passengers than humans. :-)

-Ted