I occasionally fly in and out of Copalis State Airport, the only officially designated beach airport in the USA.
https://wsdot.wa.gov/aviation/AllSta...palisState.htm This beach is ideal for aircraft operations because it has a very shallow slope, and the sand is fine and densely packed. So, during a falling tide, a large band of the sand is wet enough to support aircraft operations, and not just bush aircraft with big tires. I have seen plenty of Cessnas and Pipers with 6" wheels, and aircraft as large as a Beech 18. Overall the recommendations for operating here would also be applicable to selecting a location for an emergency landing site on an unknown beach.
- Check local tide tables.
- Dark, wet sand at low tide is the hardest for landing.
- The dry, light-colored soft sand near the high tide mark should be avoided.
- Summer landings may experience softer wet sand area (less compact) and higher risk of getting stuck.
- Avoid operating in the razor clam beds.
- Over flight is recommended before landing to check for obstructions such as exposed rocks, debris and pedestrians.
- The landing area is shared with other beach users and activities.
- Park aircraft in a row along the high tide mark.
- The busiest time is during the summer months and during the winter clamming season.
- Announce your intentions on the common radio frequency.
- Do not park aircraft overnight due to tidal changes.
- Observe all state park regulations.