'My Other Yacht Is a Support-Yacht'

Well, of course it is...

 Support yachts are for people who have outgrown their mega-yachts and need more space for their helicopters, speedboats, launches and submarines. The support yacht acts as a floating garage, trailing alongside the main yacht with all of the owner's oversized "toys."
While support yachts have been around for a while, the yacht-maker Amels has launched the Rolls Royce of support yachts -- the Sea Axe -- a gleaming, 220-feet ship that can hold a mega-chopper, loads of speedboats, a submarine, and all the scuba gear, jet skis and floaties an oligarch or sheik could ever want.
Article here 

Never thought of that... we've just been towing our Submarine for years. 

Pic O' the Day

The Better Half of Crew Istaboa, Crewing a DC-9

Melonie, when we first met, circa 1982