It deals with the 162ft 1989 Oceanfast charter yacht Mystique which has triple waterjet propulsion. There is also a list of more than 60 yachts with water jet propulsion.
So all specialists: Look at the list and make your comments. There are certainly some yachts missing and some facts that need corrections. Like the megayachts builders we are interested in we must also pursue perfection in everything we undertake!
The list includes the four Marinteknik yachts that Merijn listed (Let's play yacht trivia! topic) as well as Braveheart from Oskarshamns varv. Actually water jet propulsion was a speciality of the two Swedish yards that built the six superyachts in the late 80's and early 90's.
There is also an interesting technical feature showing the basics of waterjet propulsion: