One Mtr Patrol Torpedo Boat - EeZeBilt - India's open forum for RC flying, aeromodelling, cars and hobby stores

Quote from: K K Iyer on September 22, 2015, 11:24:09 PM

Remember that even a gnat could kill a tiger toothed sabre Grin

Have we got any pictures of the finished boat?

The PT-boats were sold as 'mosquitoes able to kill a much larger ship', but their story is really one of failure turned into success. Initially, the Americans intended to use them for jobs which they could not do - as Churchill said:

"You can trust the Americans to do the right thing - after they have tried everything else..."

Small torpedo boats were an Italian invention - they had some spectacular successes with raiding ports and sinking battleships during WW1. But, as a result, the world's navies started defending themselves against torpedo boats, with secondary guns and escort 'torpedo boat destroyers'

Torpedo boats were still useful for short-range ambushes and supporting coastal raids - but the USA had no enemy coastline anywhere near it, and could not see the need for coastal torpedo boats when any expected battle would be fought in the middle of the Pacific or Atlantic between large battleships. They were eventually persuaded to build a few experimentally, and then WW2 started.

Since the US had lost many of its big battleships, small torpedo boats were shipped to the Far East to provide a naval presence. They had been sold as 'gnats able to sink big ships' but this proved to be untrue.

In the first half of the war, American torpedo boats went into action against a number of larger Japanese ships. They did not sink any. This was entirely due to their torpedo armament, which was by far the worst of any of the combatants. There were many basic things wrong, and 3 major design flaws.

The torps were too slow, and had too short a range. They had inadequate explosive charge, and the launching tubes could fail or catch fire when used. Worse, the torpedo designs did not work.

1 due to a design flaw, the torpedos ran much deeper than their settings, and would often run under a target
2 The torpedos had a magnetic detonator which was too sensitive - resulting in premature explosions about 50ft from the target
3 When the magnetic detonator was replaced with a contact detonator, this failed to explode if the torpedo had a good hit, and would only detonate with a glancing blow.

The net result of this was that early PT-boats reported engaging Japanese ships and scoring hits, while the Japanese ships never actually sunk.

Gradually these flaws were rectified, and by the end of the war the PT-boats had aircraft-type torpedoes which were reasonably reliable. However, by then, there were few Japanese major navy ships around, and radar had advanced to the point where engaging a battleship would be suicidal - their longer range guns would destroy a PT-boat long before it got into range. However, by then the PT-boats had found a much more useful role they could perform - disrupting Japanese sea supply routes. This was often called 'Barge-Busting' - shallow draught Japanese barges hugged the coastline, immune from torpedoes, keeping the occupied islands supplied. The PT boats engaged these with deck-mounted guns, and ended the war essentially armed as gunships - in some cases they discarded two of the torpedo mounts so as to be able to carry more cannon.

The Eezebilt plan shows one of the mid-war boats, with cannon fore and aft, but aircraft torpedoes rather than tubes. If you want to do an early one, mount 4 torpedo tubes, but only a single cannon at the rear, and a mast with no radar. A later one might have 3 cannon at the bow, and a pair of rocket launchers on either side...