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The passenger will need to understand airline policies and should find out what type of documents the carrier would need... .

Accommodating Passengers With Service Animals in the Cabin

How can airline personnel help ensure that passengers with service animals are assigned and obtain appropriate seats on the aircraft?

Let passengers know the airline's policy about seat assignments for people with disabilities. For instance: (1) should the passenger request pre-boarding at the gate? or (2) should the passenger request an advance seat assignment (a priority seat such as a bulkhead seat or aisle seat) up to 24 hours before departure? or (3) should the passenger request an advance seat assignment at the gate on the day of departure? When assigning priority seats, ask the passenger what location best fits his/her needs.

Passengers generally know what kinds of seats best suit their service animals. In certain circumstances, passengers with service animals must either be provided their pre-requested priority seats, or if their requested seat location cannot be made available, they must be assigned to other available priority seats of their choice in the same cabin class. Part 382.81(c) requires airlines to provide a bulkhead seat or a seat other than a bulkhead seat at the request of an individual traveling with a service animal.

Passengers should comply with airline recommendations or requirements regarding when they should arrive at the gate before a flight. This may vary from airport to airport and airline to airline. Not all airlines announce pre-boarding for passengers with special needs, although it may be available. If you wish to request pre-boarding, tell the agent at the gate.

A timely request for pre-boarding by a passenger with a disability must be honored (see sections 382.83(c) and 382.93) Part 382 does not require carriers to make modifications that would constitute an undue burden or would fundamentally alter their programs (382.13 (c))...