Re: Retired 737 to go "in the drink"
Way back, the Boeing dive club, the Seahorses, tried to put down a Minuteman missile vertically in Puget Sound but couldn't get the environmental permits. There's already a 727 deliberately sunk off Miami and DC-3s off both Coco View & Anthony's Key Resort on Roatan, Honduras. A drug-running AeroCommander's upside down (basically wing, engines and gear only) off Bimini.
A Beech 18 is in Perch Lake, Santa Rosa, NM and an Aerostar 600 in Oronogo lake near Joplin, MO. Dived on all of them except the '27.