Yes, you can take aerosol sunscreen on a plane, but the rules differ based on where you store it. For carry-on bags, the container must follow the "3-1-1" rule: it must be 3.4 ounces (100ml) or less and fit in your single quart-sized liquids bag. Most full-sized aerosol cans exceed this and must be packed in checked luggage. For checked bags, the FAA and TSA allow medicinal and toiletry aerosols (including sunscreen), provided the total aggregate quantity per person does not exceed 2 kg (70 oz) or 2 L (68 fl oz). Each individual container must not exceed 0.5 kg (18 oz) or 500 ml (17 fl oz). It is crucial to ensure the nozzle has a protective cap to prevent accidental discharge during the flight. Be aware that a TSA officer has the final discretion; if the aerosol is labeled as highly flammable or lacks a cap, it could be confiscated during screening at the checkpoint.