re: drones and cruise ships. First, I am an avid drone pilot. I am also a well known maritime aerial photographer. While passengers are not permitted to use drones (and I'll get to that) many of the cruise lines have brought professional drone companies aboard their ships for marketing videos. However, consider the mega ships carrying 3-5000 passengers. It is easier to simply say no. If Princess has varying rules, kudos to them. Your mileage may vary as one might gather..and rules can change on a dime. And yes, most cruise ships scan and send all luggage through xray machines for every time anyone re-boards. Liquor is not a lipo battery. LOL
Obviously, LIPO batteries are a major concern. cruise ship staff has neither the time or expertise to determine if your batteries have been discharged to 30% or ensure you are bringing batteries in LIPO safe bags. While airlines publish Lipo battery limitations, cruise ships view batteries no matter what the technology as flammable. To permit drone batteries to be brought aboard and kept separately would require creating steel safety housings in the cargo area to store them. It is too much of a headache. I have suggested to several cruise lines developing a "Shore excursion" offering a drone permitted cruise for a small group, where the cruise line handles the drones with batteries removed on embark, and provide at shoreside, with all the permitting at various ports already cleared in the "tour group." A money maker as a "private tour." However, most drone pilots want to be on their own, so I don't think it would really work...but perhaps an introductory class for novices could work. Or the ship could supply 6 or 10
Phantom 4 drones and make it a real money maker. As for launching drones from a ship, it is not the vessel's speed as much as the massive turbulence that a ship sets up as she plows through the air. I regularly fly robust helicopters over my client's ships. There is an aerodynamic bow wave, turbulence admidships and more disturbance towards the stern. Good chance the drone would land, crash, go into the water or hit someone on the Lido deck or in the pool. In ports, without the local country's permitting, it's not gonna work. As for many ports in the Mid-east, they are military controlled and a drone in the port would face severe penalties. One drone team, contracted by a cruise line to fly the drone off the ship, attempted to do so in the SUEZ canal. Someone was really dumb. they were fined heavily and drones were confiscated by the Egyptian authorities..or at least temporarily. In the Port of NY much of the same issues abound including that NYC is officially a "no drone city." The passenger ship terminals in the Port are owned by the Port Authority of NY/NJ and have massively strict protocols for any drone usage within their jurisdiction. Not to mention concerns of NYPD, NYPD Aviation, NYPD Marine Intelligence and Sector NY USCG.
Caribbean nations also have changing and variable rules and it behooves to be aware of their rules way ahead of any travel by any means.
Just my two cents.