Consider your flight options. We strongly discourage the use of other than nonstop flights, especially for pets that will not be traveling in the cabin. Avoid weekend or holiday flight periods as the high numbers of travelers during these periods may prevent your pet from receiving as much attention as it should. If your pet will not be traveling in the cabin with you, avoid travel during very cold or hot times of the year and make certain that flights are early morning or late night if during the summer and midday if during the winter. The USDA prohibits the shipment of animals where temperatures at either the origin or destination are below 45 degrees or above 85 degrees.
Many airlines have further temperature-related restrictions.
Inquire as to the aircraft type planned for the route. McDonnell Douglas aircraft, including the MD80, DC9, and the DC10 will not accommodate 500-size crates. Contact the airlines. Each airline has their own rules and regulations, beyond the USDA's minimum requirements, concerning what types of pets they will transport and how they will transport them that you will need to discuss. Let the airline know the expected weather at your origin, destination, and any transferring cities, as well as the type of pet you have, its size, the type and size of its carrier, weight, temperament, and health.