US motor torpedo boat PT-105 carves the water, wartime date uncertain.  Best regards, JR.

USS PT-105.

Elco (Electric Launch Company) pattern US Navy PT (Patrol Torpedo) boat (as usual) at speed.  The main armament of PT boats consisted of torpedoes and depth charges.  While they did carry guns for defensive purposes, their main defence lay in their speed and manoeuravability.  Armour was nil - the hull construction, like that of the civilian pleasure speed boats upon which their design was based - consisted of a specialised form of plywood.  However, this was found to be very strong, and PT boats proved capable of absorbing a surprising amount of battle damage.

PT boats were widely deployed by the US Navy and Coast Guard, in particular, in the Pacific, but also in the Mediterranean, and out of the south east coast of England.  Best regards, JR. 

Mosquito of the Sea.

Lieutenant (Junior Grade) John F. Kennedy, USN,  as commander of motor torpedo boat PT-109, operating out of Tulagi.  In August, 1943, Kennedy's boat was rammed and cut in half by a Japanese destroyer.  The PT (or its halves) stayed (surprisingly) afloat for some time; but the crew were eventually forced to swim to a neighbouring islet, from which they were rescued.  In the course of this incident, Kennedy aggravated an old back injury, the effects of which still seriously affected his health in later years - all the way to the White House.

Kennedy recovered sufficiently to enjoy a further career in command to the end of the war, which he finished as a highly decorated war hero.  When asked how he had become a war hero, he is said to have answered, "It was easy - they cut my PT boat in half !".  Best regards, JR.