This is Scout, a miniature horse that works as a guide horse.  I saw him and his partner at the Cincinnati airport and asked if I could take a picture as I had never seen a guide horse before!  Yes, he did get on a plane! Please note the sneakers. These have become more and more accepted by guide horse users as horseshoes tend to set off metal detectors at airports.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/18309730@N00">DanDee Shots</a>
CC BY 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/18309730@N00/295965213/">Guide horse</a>