“These [drones] are not allowed at the airport in any way, shape or form, whether they are flying or coming through your checked luggage. So while it’s not a prohibited item the airlines are not allowing these on the planes.”
— Greg Meyer with the Fort Lauderdale-Hollywood International Airport, as quoted by NBC Miami
According to a story in Forbes, the issue may be the ithium polymer batteries that are used to power the devices. These batteries are also used in hoverboards and when punctured or suffering from defects can pose a fire hazard. However, as the Forbes article notes, “Those same batteries are also used in many notebook computers and other small electronics.”
Most travelers probably don’t give much thought to which batteries are allowed and where (i.e. in the cabin vs checked vs not at all). Well there are guidelines for that. While the TSA does not specifically prohibit drones. They also allow up to two larger lithium ion batteries (more than 8 grams, up to 25 grams of equivalent lithium content per battery) in passengers’ carry-on. This size covers larger extended-life laptop batteries. Most consumer lithium ion batteries are below this size.