For those of you chomping at the bit (including your always humble editor) to take issue with the word "plywood," consider this; words often take on different meanings for succeeding generations. The rudimentary "computers" used about U.S. Navy vessels during World War II served an entirely different function than those aboard ship today. Today's plywood is composed of thin sheets of wood (of various dimensions), joined together by the generous use of glue. PT boat hulls were composed of double planked 1" mahogany fastened with monel (copper-nickel alloy, very salt water resistant, really quite expensive - ed.) screws. Sandwiched between the layers of mahogany planks was a layer (or ply) of canvas. Every other wooden feature on the PT boat was traditional plywood. If the hull had been plywood, as some mistakenly believe, the boat would have disintegrated from the pounding that the hull underwent while underway.
PT boats used three 12-cylinder Packard Marine Engines, 4M-2500, which burned one-hundred octane gasoline. These liquid-cooled power plants could generate anywhere from 1,200 to 1,500-hundred horsepower depending on conditions at the front and the period of construction. The Packards were lightweight, dependable, and situated two engines forward in the engine room, one port and one starboard, and the third engine farther aft on the centerline. This made service of the engines in the relatively cramped confines of the engine room possible. Yes, the boats were fast; perhaps 40-knots under favorable conditions with the boats graceful bow jutting proudly above the water's surface. On occasion a good third of the boat's hull would come free of the water as she maneuvered across the water. In ideal conditions a PT boat was a most formidable weapon.
Conditions in the Pacific Theater were rarely ideal. Distances, living conditions, diseases, and lack of resources (the boat's engines should have been changed out every one-thousand hours of operation), all combined to severely impact the capabilities of boats and crews. Many photographs of PT boat crewmen from the forward areas of the Pacific show a lean bunch of bearded men, scantily clad, standing on the cluttered decks of what, to the untutored eye, must surely have been a barge. As the sailors had undergone a change (their training at Newport, Rhode Island could hardly have prepared them for the primitive living conditions that they encountered), so had the trim lines of the PT boats. They were boats that would become lethal instruments of war.
All torpedo boats had been designed as a means to deploy torpedoes against enemy vessels. What better way to disable or sink an capital ship than by the use of a fast, difficult to see and hit boat with a low silhouette? They became all the rage in the navies of the early 20th Century. Torpedo boats and their nemesis torpedo boat destroyers (yes, that's how these predators who later chased undersea quarry were born) began to share the oceans with traditional vessels.
When World War II began the Patrol-Torpedo, or PT boats of the American navy was viewed as a customary extension of that concept -- little, fast boats to launch torpedoes at slow, big ships. But as the war progressed in the South Pacific, the needs of the warrior changed. The ideals of high sea's encounters that so many naval strategists had dragged into the war were quickly shattered by aircraft carriers. Vessels often didn't see one another and there was certainly no role for the diminutive PT boat in single combat covering hundreds of square miles of open water.
But there were other battlegrounds for the Higgins or Elco boats. Every island in the South Pacific had the potential of harboring the enemy and there thousands of islands scattered about these vast distances. General Douglas MacArthur's strategy of island hopping reduced the number of islands that were to be invaded to a manageable level, but that number was still in the hundreds. There were islands to be by-passed, invested, subdued, ignored or contained. Islands surrounded by shallow water -- water perfect for the PT's modest draft.
PT boats were soon hunting Japanese supply and troop barges, Japanese coastal vessels, and Japanese submarines. They were sent out to rescue downed pilots, or take scouts close to shore, or rendezvous with coast watchers. PT boats were targeted by shore batteries on virtually every mission, so they relied on three attributes. The boats were (despite the abominable condition of the boats and engines), still very fast and maneuverable; crews coveted their speed and worked miracles to keep the engines in shape. PT boats were stealthy; despite their 80-foot length and 40-ton displacement (both varying from boat to boat), they could close their mufflers and ease on the quarry -- the throaty roar of the powerful engines reduced to a whimper as long as they maintained a speed of no more than ten-knots. Anything more than that and the force of the exhaust would blow the mufflers off the vessel.
There was a third element on which the PT boats of the South Pacific depended, one that at first glance might raise an eyebrow of a chair-bound naval traditionalist of the period; these little guys were armed to the teeth.
The first ten PT boats delivered to the United States from the Elco yards in Bayonne, New Jersey carried four MK-VII torpedoes, and two-twin mount .50 caliber machine gun turret with Plexiglas canopies; similar to the turrets on bombers. The boats also had an assortment of weapons that included, hand grenades, .03 Springfields, and Colt .45 caliber semi-automatic pistols, and bow mounts for two Lewis guns.
Well before PT boat crews found themselves skirting in and out of shallow waters looking for mischief, the armament aboard PT boats began to change. First to go was the Dewandre Plexiglas turret; the darn thing fogged up and made visibility nearly impossible. Then some bright young officers eyed the four torpedo tubes, which housed the torpedoes. Besides the weight of the tube, torpedoes exiting their containers sometimes created a bright, but short-lived fire in the tube -- usually sparked by grease. There was no danger from the fire itself, but advertising your position in the face of the enemy is not advisable. So the tubes were gone, replaced by a simple device that dropped the torpedo over the side. And anyway, as the island war continued there weren't that many targets against which torpedoes would be effective. The Japanese barges, often heavily armed with shallow drafts, traveled at night. These barges stayed very close to shore, following the contours of the shoreline. It fell on PT boats to hunt out and sink these barges and so they began to arm themselves for the task
Americans are great scavengers and one creative band of PT boatmen salvaged a 37mm automatic cannon out of the wreck of a P-39. While the aircraft never found favor with Americans, its cannon enjoyed a great deal of popularity on the bow of a PT boat. Soon, these cannons became standard on the boats. To keep pesky Japanese aircraft at bay as well as worry the Japanese barges, some inventive types began installing 20mm cannons on the bow and amidships. These guns had a range of 5,500 yards and a rate of fire of 450 rounds per minute. Elco engineers even came up with the Thunderbolt system consisting of four MK 20mm cannons on a single mount. By this time the ambitious PT boat crews had apparently decided that it would be handy to have a 40mm cannon on board as well. These were soon installed on a number of PT boats with twin rocket launchers, each housing 8 5-inch rockets. Of course I won't mention the additional single or twin mount .50 caliber machineguns that kept sprouting up from the deck. Or the Thompson submachine guns, M-1 rifles, M-1 carbines, Colt .45 semiautomatic pistols, and Browning Automatic Rifles. I won't even take the time to mention the 2.36-inch rocket launchers (commonly called the Bazooka), and .60mm mortars that some boats carried. It's a wonder that the 40-ton boats didn't sink under the weight of all of that iron.
The contest between the barges and the PT boats was a confusing, close-quarter engagement in almost total darkness with the superior firepower and speed of the PT boats usually resulting in an American win. It was dangerous, deadly work but gradually the Japanese, who had been denied the opportunity to move reinforcements and supplies by superior Allied airpower, found that even their intricate barge-network could not withstand the assaults of the PT boats. Nipponese outposts withered on the vine, effectively pruned to extinction by torpedo boats transformed into heavily armed gunboats
The needs of combat changed radically throughout the island battlefields of the South Pacific. On the great ocean gray-clad fleets ranged over the watery landscape throwing up clouds of aircraft in a desperate attempt to annihilate one another and the destruction that was rendered on a grand scale was monumental. But around the shallow waters of nameless islands, and in the lagoons and bays that would eventually become rusty with the carcasses of unlucky ships, low-slung shadows moved ominously, looking for prey. These PT boats were, pound-for-pound, the most heavily armed warships afloat. They became gun platforms because it was necessary for them to go heavily armed. Americans, a naturally creative and inventive lot, turned their sleek PT boats into deadly instruments of war; vicious little predators who waited along the dark shores of distant islands for the enemy.
http://www.military.com/NewContent/0,13190,Wilson_032805,00.html
Some technical details corrected.
The hulls were not plywood, but mahogany in layers, like one boat hull inside another boat hull, with the wood grain direction of these two layers at perhaps sixty degrees (educated guess). Under way the hulls flexed under the pounding, so a waterproof layer was built between them.
There was a certain PT skipper who received orders to intercept a Japanese convoy at a certain spot that the convoy was certain to pass that night. The boat arrived at the correct location without incident. However, when the convoy arrived they found all of the crew asleep but one, maybe. A Japanese destroyer saw the waiting PT and rammed it. The crew apparently did not notice any of this until the destroyer was a few hundred yards away, and did not even give the idling engines the gas. This is clearly the responsibility of the commanding officer, who was certainly asleep.
"The idling PT boat was rammed by the Japanese destroyer Amagiri on August 2, 1943 in the Blackett Strait between Kolombangara and Arundel in the Solomon Islands, cutting it in half and killing two men."
The story, as I understand it, is that this unnamed PT skipper had a very influential father, a very heavy contributor to the Democrat Party, a big enough contributor to have been the United States Ambassador to The Court of Saint James. Great Britain, folks. A most plum job, reserved for the most generous.
I know no reader here will need to be told this clown's name.
Anyway, he was not court martialed. Daddies in high places beats malfeaseance in the face of the enemy, hey. Especially during that administration.
I wonder who you could be talking about. Give us a hint, did he ever run for political office?
I've read somewhere that the Packard engine referred to here was a modified Allison V-1710, similar to what powered the P-38, 39, and P-40?
Most excellent read, Iris7.
The PT-109 incident has been so "glorified" that few now-a-day know that it was really a screw-up that would have gone unoticed or at most a footnote in history except for "friends" in high places and the fact that the Skipper became famous later in life.
See post 47: According to my Uncle "Bud" there were actually two types of engines. The newer ones generated about 300 more HP than the older ones. He also informed me that the Japanese had what he called an "I" Class destroyer that could out run but not out turn some of the older boats. They had an incident where one of the older boats had to play ring around a small island all day for the boat to get away. The PT boat could get in closer to the island and both the Jap destroyer and PT boat spent almost an entire day running around an island. The island was high enough to where the destroyer could not fire across the island to hit the PT boat.