Early 1980s book I checked out of my local grade school library.  I left that school in 1986/1987 so it would have been published prior to that and it didn’t appear to be brand new when I checked it out.  What I recall:

1980s children’s picture book about future vehicles (in a similar style of Syd Mead). My primary focus of the book was the submarine image as I was obsessed with the ocean at the time.  The submarine appeared to have solar panels on the top of the hull and a raised platform (similar to the control portion of an aircraft carrier) that had the shape of a fin (like sports cars have on the rear) with two risers and a flattened, wing like top.  I believe (but could be mistaken) that there was a helicopter landing pad on the raised platform.

The submarine itself was massive and the front swept back like a manta ray or a shark’s pectoral fins.  The front “fins” had two, large engines (appeared to be similar to jet-intake engines like on a large plane) but obviously for aquatic propulsion.

I have attached a couple images: one is of a sports car tail-fin for reference and the other is a crude drawing of the submarine as I remember it.  Emphasis on the “crude”.

I have been trying in vain to find the book, or at least the image in the book of the submarine.  Hopefully, this will bring an end to my search!  Thank you!