Conventionally, flying with a baby capsule must be a fully collapsible stroller. However, numerous airlines permit you to use a specific travel system - a stroller frame and an infant car seat in combination. Let’s take American Airlines as an instance. According to their pushchair policy, the stroller must meet the following requirements to count as a carry-on: - It must be smaller than 22 x 14 x 9 inches (including handles and wheels) - The stroller must fit in the carry-on sizer at the check-in counter  If customers bring both the pram and the seat, they can check only one baby system for free. And strollers over 20 pounds must be checked at the ticket counter.