As we've seen before, airlines are constantly going bankrupt and cumulative earnings across the history of American passenger aviation are negative $33 billion. It turns out that getting out of the conventional business of carrying human passengers doesn't really solve the problems:
Pet Airways — once the great transportation hope for animal owners — is now suffering a fate similar to its counterparts that cater to human travelers.
Dog and cat owners are angry about canceled flights. Travel sites are abuzz with complaints, including customers who claim they have not received refunds for paid-for flights. And the company is burning through cash at a rapid rate.
So the search for sustainable aviation business models goes on, with Southwest retaining its status as the only U.S. company to have ever really cracked the code.