An article I read said that nobody else knows what an HC-144 is, either. Being USCG, with and H designation, ATC often assumes it is a chopper. In one case they offered to let them land on the ramp and the pilot's response was, "I can only do that once. I'd rather use the runway."
H, as a prefix, of course means "Rescue" but it used to mean Helicopter. That is where the Huey got its name. It was HU-1, meaning a Utility aircraft that was Helicopter, before deciding that H as a primary designation would mean Helicopter and U would be Utility, making it a UH-1.
How many H prefix fixed wing aircraft do we have? HC-130 and now HC-144, based on the Airbus CN-235, which is another one I've never heard of.