I hope this helps... http://www.nps.gov/lyjo/planyourvisit/presidentialvehicles.htm

Amphicar

Built in Germany from 1961 to 1968, the Amphicar is the only civilian amphibious passenger automobile ever to be mass produced. A total of 3,878 vehicles were produced in four colors: Beach White, Regatta Red, Fjord Green (Aqua), and Lagoon Blue--the color of President Johnson's Amphicar.

President Johnson enjoyed surprising unsuspecting guests when taking them for a ride in his Amphicar.

The President, with Vicky McCammon in the seat alongside him and me in the back,was now driving around in a small blue car with the top down. We reached a steep incline at the edge of the lake and the car started rolling rapidly toward the water. The President shouted, "The brakes don’t work! The brakes won’t hold! We’re going in! We’re going under!" The car splashed into the water. I started to get out. Just then the car leveled and I realized we were in a Amphicar. The President laughed. As we putted along the lake then (and throughout the evening), he teased me. "Vicky, did you see what Joe did? He didn’t give a damn about his President. He just wanted to save his own skin and get out of the car." Then he’d roar. --Joseph A. Califano, Jr