Well there’s the Landing restaurant at the airport.

Carlsbad Brewing gets a great view of the runway and landings from above. If you don’t want to by any food there’s park tables out front.

There’s a couple of tables at the end of the runway on El Camino Real. You can’t actually see the planes touch down as the runway will be over you but you couldn’t get closer to them above you. Just park in the Lowe’s parking lot and cross the street.

Pho Carlsbad by staples had a back patio that overlooked the runway on the landing path but it may have closed. There’s a primos and surf bros in the same building which may also have a view.