Sounds like a movie, right. No snakes on this plane, but there were tarantulas hitching a ride from Punta Cana to Canada.
Cacatas on a Plane:
http://www.cbc.ca/news/canada/montreal/tarantula-plane-air-transat-1.3590780
Cacatas on a Plane:
http://www.cbc.ca/news/canada/montreal/tarantula-plane-air-transat-1.3590780