United Airlines is investigating the death of a giant rabbit which was being transported on one of its planes.
The 90cm-long bunny was found dead in the hold when the flight it was on arrived in Chicago from London Heathrow.
Out of the many animals that travel each year, most are put in with the cargo, where the pressure and temperature are controlled.
In 2016, the Animal Reception Centre at Heathrow Airport handled 17,500 cats and dogs and a whopping 786.6 million invertebrates.
But here are a few examples of pets who have been given first class treatment in the sky.
Falcons to Saudi Arabia
Earlier this year, 80 falcons boarded a flight to Saudi Arabia.
Turkey-based businessman Ahmet Yasar posted the image on social media and said: "It is quite common for airlines in the Middle East to transport birds for hunting purposes. In this case each falcon is estimated to be worth about $8,000 (£6,435)".
Pandas to Scotland
Edinburgh Zoo's pandas, Tian Tian and Yang Guang, are on loan from the Ya'an reserve in Chengdu, China.
The pair's nine-hour flight in 2011 required 21 months of planning with three teams in three different countries. They were put in a FedEx Express carrier and settled in very well apart from the jet lag.
Turkey to Salt Lake City
Easter the turkey travelled with its owner Jodie Smalley from Seattle, who was flying to Salt Lake City.
She said: "The flight we went on was only an hour and a half long. During the flight she was quiet and well behaved. She had a diaper on from a site that specialises in bird diapers and it works really well!"
Jodie had recently been through a separation and bereavement, she struggled mentally and emotionally but found Easter a source of comfort.
And one pig that doesn't fly
Before getting on the plane, meeting Lilou could calm your nerves.
She is one of the therapy animals at San Francisco International Airport and part of the Wag Brigade. The group, who are mostly dogs, wear vests that read "Pet Me!" and roam the terminals helping anxious passengers have a relaxing flight.