In the bleak months following Pearl Harbor, the general public was well aware
that the U.S. Pacific fleet was antiquated as well as outnumbered. The
prospect of hurling our remaining capital ships into a conventional war of
attrition would have seemed suicidal. However, during the desparate process
of rebuilding, the average American could identify intimately with the
vision of individual small craft roaring to counterattack. More powerful
than might alone, the St. George imagery provided the assurance of righteous
cause around which to muster the all-volunteer force.
While the PT boat is still a popular icon of World War II, many misconceptions
remain regarding the type and its development. The motor torpedo boat was not
born precipitously on the eve of hostilities, nor was its concept unique to the
United States. The Elco and Higgins PTs represented a refined combination of
hull design, power plant, and weapons that were all invented in the 19th
century. Powerfully armed, yet vulnerable to fire, mass produced, yet of
superior performance, the PTs embodied many design contradictions.
That the boats could be finely tuned to meet the demands of the front lines,
and still be produced at such an unprecedented rate, make the PT program one
of the greatest accomplishments of the wooden boat building industry.
Origins of the Motor Torpedo Boat
The essence of the torpedo boat concept lies in radical tactical responses to
convential naval strategy. By the time of the American Revolution, accepted
naval doctrine called for sending a fleet of floating wooden fortresses
either to trade fire with their enemy counterparts or to blockade its ports.
Blockade strategy was as tedious and stagnant as sieges in medieval Europe or
trench warfare in World War I. Both of the latter static strategies were
outmoded respectively by the invention of artillery to breach walls and
armored tanks to span trenches.
The Development of the torpedo boat was governed by advances in hull design,
power plants, and weaponry. Robert Whiteheads's invention of the
self-propelled torpedo in 1876 along with the multiple expansion steam
engine led to the first modern torpedo boats. One particularly famous
example was N.G. Herreshoff's conversion of the launch STILETTO to fire a
torpedo over her bow. The conventional mindset of the Navy gradually pushed
for ever larger torpedo craft, a move which led to the development of
fleet-size ships and the destroyer. At the turn of the century, one of the
most infulential proponents of the torpedo boat was none other than then
Assistant Secretary of the Navy Theodore Roosevelt. In answering critics
who dismissed the boats as dangerous aberrations, the aggressive statesman
showed remarkable insight in predicting the hit-and-run role of the PT
while conceding that \"...they will always be as fragile as they are
formidable.\"
Design Development Between the Wars
Motorboating in the depths of the Depression was highlighted by the designs of
Gar Wood and the Gold Cup racers. It is only natural that these fire-breathing
unlimiteds are often cited as the forebears of the PT boat. Despite their
thrilling performance, these boats show little if any influence in the design
of the torpedo boats of World War II.
As with the torpedo boat, the concept of the stepped hydroplane is an old
idea. The hull is designed purely as a lifting body to reduce resistance. In
fact, the whole thrust of the hydroplane is to deny its own element by
skipping above the surface of the water. Thornycroft used the idea in World
War I in designing its 55' Coastal Motor Boats. Though fast, the boats were
severly limited by range, armament, and sea conditions.
While less radical, the early warped V-bottomed hulls lie at the heart of
torpedo boat design. The idea is generally credited to yacht designer
William H. Hand, Jr., in around 1902. His adaptations of Chesapeake deadrise
hulls possessed the unique combination of high speed, comfort, low power,
and good seakeeping ability. By World War I, Hand's larger boats were
reaching 35 mph and winning ocean races. The British Admiralty took note
of the designs and ordered a series of 40\' patrol launches.
Ironically, the U.S. Navy showed little continued interest in small attack
craft during the '20s and early '30s. General Douglas MacArthur, then
commander of Philippine forces, foresaw an escalating threat of invasion
and proposed a program to build a squadron of 30 motor torpedo boats to
defend the islands. The 70' all-aluminum design presented by MacArthur's
naval assistant, Lt. S.L. Huff USN (retired), followed the well-tested lines
of a 45' Luders crash boat. However, preliminary studies showed that the
horesepower necessary to bring the boat to 40 knots would be enormous. The
approved propulsion plan proposed jamming 6 550-hp Hall-Scott engines into
the tight engine room. No boats were built to Huff's design.
With the support of Secretary of the Navy Admiral Pye, the U.S. initiated its own
design program in December, 1937. This testing produced three 25' half-scale
boats, each powered by two 140-hp engines. The boats all varied in angle of
deadrise, height of chine at bow, transom immersion, and location of the center
of buoyancy. The results of this program produced valuable data on loading and
trim, handling, and other requirements needed to get over the hump and onto
plane. In July, 1938, the Navy's Bureau of Construction and Repair sent out
invitiations for a design competition.
Scot-Paine, Sutphen, and the Plywood Derbies
The designers only had two months to submit entries. Finalists would be
awarded $1,500, and the contract winners $15,000. The competition was for
two designs; a 54' boat that could be easily loaded onto a mothership,
and a 70' boat with increased range. Entrants submitted 24 designs for
the smaller boat , and 13 for the larger.
Speedboat professor George Crouch was working for Henry B. Nevins, Inc. at the
time, and won the competition for the 54' boat. Not unlike his earlier
racers, the boat had a pronounced barrel back and a flat, hollowed-out
underbody. The torpedoes were launched by sliding of rails over the stearn,
an idea borrowed from Thornycroft in England. This flawed concept meant
that the boat would have to be up on plane to fire its tubes, so it could
accellerate and swerve out of the way of its own torpedoes. However, this
meant that the torpedoes would start their run in turbulent water behind
the PT, and could easily veer off course. Plagued by construction problems,
lack-luster performance, and the decision to scrap the small boat/mother
ship concept, only four of the Crouch designs were built.
Sparkman & Stephens won the design competition for the 70' boat. Two
prototypes, PTs 5 and 6, were to be built at Higgins Industries in
New Orleans. The design was unique as probably the leanest of the PTs,
with only a 5:1 length-to-beam ratio. Verteran builder Andrew Jackson
Higgins predicted the hull design's poor lift and low top speed of only
33 knots. Higgins successfully petitioned the Navy to dump the prototype
by selling it to Britain, and he started from scratch on his own designs.
Amidst this proliferation of designs and prototypes, Henry Sutphen of Elco
remained notably removed. The shrewd builder could see that meeting requirements
for performance, armament, and seaworthiness exceeded all conventional designs
and would demand more experimentation--all at the considerable expense of the
competing contractors. Instead of wading into the fray with his own set of
plans, Sutphen focused on the work of a flamboyant British entrepreneur.
Hubert Scot-Paine was an eccentric and a visionary who threw himself into the
forefront of the transportation revolution in the 1920's. He founded British
Airways and Supermarine Aviation, who 1934 Schneider Cup Trophy-winning float
plane was to become the prototype for the Supermarine Spitfire. No less
consumed by the speed on the water, Scott-Paine founded the British Powerboat
Company and campaigned a series of boats against Gar Wood and his supercharged
Packards. In 1935, Scott-Paine designed and built 22 air-sea rescue (crash)
boats of 64' LOA. With the renewed interest in heavily armed torpedo boats,
he expanded this plan in 1938 to a design for a 70' boat carrying four
torpedoes and powered by three 900-hp Merlin engines. Though the boat reached
44 knots on trials, Scott-Paine lost the contract to Thornycroft Vosper.
The controversy surrounding the Admiralty's decision left the designer bitter
and in search of a buyer for his ideas.
The superior performance of the Scott-Paine boat was not lost on Assistant
Secretary of the Navy Charles Edison. By January of 1939, virtually all of the
domestic private and government proposals had proven flawed. But, however
desperate the Navy might have been to begin production, it did not want to
appear to be selling out American boatbuilders by throwing in with the British
Powerboat Company. In a clandestine meeting, Edison sought out Sutphen to act
as a straw man to buy the Scott-Paine prototype and ship it back to the U.S.
for trials. The boat arrived in New York two days after the outbreak of war
in Europe.
Elco was granted a contract almost immediately to build two squadrons (24) of
the Scott-Paine 70-footers. The boats were completed and deployed for testing
in Florida in the summer of 1940. Some severe structural problems surfaced
shortly after testing began. The decks had a tendency to crack at the beginning
of the super-structure, and the hull-to-deck joint of one boat zipped open for
over a quarter of the boat's length. The forward underbody of the boat also
proved weak and needed to be reinforced with additional frames. At the same
time, it became apparent that the British 70' design was overloaded by the
larger U.S. 21\" torpedoes. This prompted Elco to modify the molds of the
boat by adding 7' to the transom for the second production run.
By the spring of 1941, a number of other prototypes had become available for
testing. However, the structural defects that had been uncovered with the early
Elcos only emphasized that there would be no opportunity to alter a design after
it entered full-scale production. There was a proposal to run all of the new
designs through a rigorous sea trial that July in Long Island Sound, with the
winner being awarded the contract.
While the Navy was to test the boats for many practical details such as
habitability, communications, and production standardization, it was generally
understood that they intended to take fully loaded boats and kick the stuffing
out of them in order to select the survivors. The sea trials culminated with a
190-mile run around Block Island, the Fire Island Lightship, Montauk Point, and
back to New London that has become know as \"The Plywood Derby.\" What was
originally intended as a conventional endurance run became a free-for-all in 15'
seas.
The leader, an Elco 77, managed to finish in just under six hours for an average
speed of over 39 mph. Surprisingly enough, the small boat was able to hammer
through the rough conditions and cross the line only minutes behind the
destroyer WILKE, which had been sent out to pace the fleet at full speed.
Virtually all of the leaders suffered some damage. Though they were fast,
the Elcos pounded so badly that their decks buckled and cracked. Later models
were fitted with large stringers on deck running alongside the house and onto
the foredeck.
Higgins had fielded two entries that competed against each other. Veteran
designer Graham Haddock had engineered the new PT-6 that replaced the failed
S&S design. Though structurally superior to virtually all the other entries,
it couldn't keep up with the lighter Elcos. The other Higgins boat, the 72'
PT-70, was designed by the builder's son. The new boat used lightweight
construction with plywood topsides and deck and matched the speed of the
Elco 77s. However, the plywood shattered early on in the race, forcing
the boat to withdraw. Higgins decided to build a larger version, using
some of Haddock's structural innovations (Haddock himself was pulled from
the project and relegated to steel construction).
The Huckins entry proved to be an unexpected disappointment. The 72' PT-69
was notable for its plumb stem with deep forefoot, and a sharp entry that
warped to only six degrees of deadrise at the transom. While she was able
to reach a fairly good speed, the boat was reported to have handling problems.
The Huckins boat was unique in being powered by four Packard engines rather
than the customary three, a complexity that the Navy did not consider favorably.
Ultimately, only two squadrons of the Huckins boats were built, and these were
consigned to defending the Panama Canal.
The First Elcos in the Pacific
With their clipper bow, reverse sheer, and swept-back superstructure, the early
Elco boats possessed the most flamboyant aesthetic character of all the PTs.
The styling and structural details of the boats embodied the aero design
concepts of the era--to the point that the first squadrons were fitted with
domed plexiglass machine gun turrets. Armed only with their torpedoes and
several defensive guns, the boats and their crews seemed to possess an
innocence and overconfidence that would evaporate during the first bitter
campaigns in the Pacific.
Elco PTs were dispatched immediately to buttress the Pacific fleet. In fact,
there are accounts of men from Squadron Two who fought off Japanese planes at
Pearl Harbor while their boats were still stored on shipping cradles. Squadron
Three was sent to aid in the futile defense of the Philippines. Faced with a
determined and vastly superior invading force, the boats struggled on with
dwindling supplies and spare parts.
The early shortcomings in the PT program were due to operational and support
problems rather than hull design. The small boats were not self-supporting,
and so had to be deployed with mobile bases that would include engine shops,
floating drydocks, and massive fuel and ammo dumps. This interdependent
network compares more closely to an airfield than it would to most naval
detachments deployed at sea. The maintenance was typical for any wooden boat,
and the constructions actually lent itself to quick field repair and
modification.
PT actions during the defense of the Philippines in the spring of 1942 and off
Guadalcanal later that year proved that the boats were ideally suited for
hit-and-run tactics. Teams of four boats would set out after dark on long-range
patrols. Each boat ran on a single muffled engine. After contacting the enemy
(often at ranges well under 400 yards), a PT would fire all torpedoes
simultaneously, light up all three Packards, and throw the boat into a series
of evasive maneuvers to escape.
Plagued by poor communications, only fair support, and notoriously defective
torpedoes, the PT sailors would come to prize performance as their greatest
defense. In fact, the boats were so hard to hit that by the end of the war,
only eight PTs had been lost due to enemy fire. (By comparison, 18 boats had
to be scuttled to prevent capture following grounding. Enemy aircraft were a
greater threat than surface ships, for they could home in on the phosphorescence
thrown off in the PTs' wakes.)
These early clashes with the destroyers of Rear Admiral Tanaka's Tokyo Express
also demonstrated that any argument regarding the fragility of the wooden,
gas-powered PTs was essentially moot. While riding into combat on top of 3,000
gallons of aviation fuel hardly inspired confidence in PT crews, they knew that
the rapid-fire 5\" cannons mounted on the Japanese destroyers would be able to
track a larger diesel boat and would vaporize it just as quickly. It is for
this reason that continued PT design efforts concentrated on seeing that the
boats would not get hit in the first place.
Elco and Higgins--The Great Rivalry
The early experience of Squadron Three in the Philippines proved that the 77'
Elco hull needed several major modifications. The boats were still subject
to structural failure, primarily buckling at the deck and clamp, due to the
severe compression loads incurred from hammering through seas with a full
warload. Without stopping production, Elco rengineered the design and
eventualy launched the first Elco 80, PT-103, in May 1942.
The new boat had a radically different profile from her forebear. The clipper
bow of the smaller boat was given up for a simple raked, spoon stem. The plans
show that the extra length was gained by adding a station at the bow. The
chines were swept up to the new stem almost 4' above the waterline. The
\"nose job\" gave the Elco 80 a finer entry with more deadrise, all in an
effort to smooth the pounding of the original Scott-Paine design. However,
the deadrise from the transom to approximately three-eights of the boats's
overall length (that portion of the hull where the underbody sections are
still fully immersed when the boat is up on plane) remain precisely the
same as the 77' Elco. This is interesting in that, while the new boat
displayed wider beam at the chines and deck throughout, there was an obvious
attempt to retain the speed and planing characteristics of the original.
The outboard profile of the Elco 80 is marked by a simplified, low-profile,
stepped house mounted well aft. By 1945, the deck profile was cluttered with a
myriad of deck guns, radar, and auxiliary equipment. Despite its similar
underbody, the 80' boat bore none of the streamlined aesthetics of the
Scott-Paine design. This purely functional aspect of the Elco 80 design is
borne out of the fact that virtually every design change was the result of
field experience, and demands that the PT boat fulfill a wider spectrum of roles.
The end of consequence of these modifications was that, while the first
operational 77' Elcos displaced 46 tons, the last Elco 80s tipped the scales at
more than 60 tons.
With over 300 boats built, more Elco 80s were produced than all other designs
combined. The reason for the design's popularity is that Elco was able to fill
every contract ahead of schedule, modify the boats on a continuing basis (to the
point of overloading), and still come close to original performance criteria.
The boats were liked by their crews, in no small part due to the well-laid-out
accommodations, as well as performance.
Nevertheless, the Elco 80 retained several notable weaknesses. The new boat
was not nearly so maneuverable as the Higgins, it still tended to pound, and
it was several knots slower than the smaller Elco. The success of the boat
rested in its ability to strike the best compromise. Given the distinctly
unforgiving demands placed on the PT fleet, it is no surprise that the design
with the fewest vices took the lead.
The Higgins design bore no resemblance to the Elco 80. Where the Elco boat
gradually evolved from the original Scott-Paine design, the Higgins 78' was
designed in-house by Frank Higgins and Teddy Sprague. The Higgins 78' was
the second major PT design to see operation, with close to 200 commissioned
by the end of the war. As with Elco, Higgins had come out with a smaller
prototype, the 72' PT-70. The Higgins 78 was designed not only to answer
the Navy's request for a larger boat, but also to redress the serious
structural problems of the prototype. The improved Higgins boat was planked
with double-diagonal Philippine mahogany on the topsides and decks, where the
earlier boat had used sheet plywood. The internal structure of the boat was
heavily reinforced, especially on the bottom. Most underbody members were
tied together with bolted galvanized steel angle or plates.
While the new boat was extremely strong, it was also more than 20,000 lbs
overweight. Unable to make the Navy's requirement for a top speed of no less
than 39 knots on shakedown cruises in September 1942, Higgins was forced to
suspend production. By June 1943, the Higgins testing facility in Miami
reported that boats with a full load were still limited to only 33 knots.
Though engineers continued to develop a \"crash diet,\" the Higgins 78 would
always be plagued by lower top speed than the Elco boats.
The Elcos and the Higgins designs had straight buttock lines aft with a deadrise
of 14 degrees under the center of gravity at the engines. This agreement on the
shape of the planing hull is most likely attributable to the Navy's 1937 tests
on warped, stepless V-bottomed hulls. The Higgins underbody had sharper
deadrise forward, and carried it farther aft. This striking difference of the
Higgins forebody allowed it to drive through much heavier seas. It is probably
this virtue (along with the failure of the first boats to reach an adequate top
speed) that led the lucky sailors of Squadrons 13 and 16 to be stationed in the
Aleutian Islands.
At the same time, the deeper vee of the Higgins kept it from burying its lee
chine forward when the boats were thrown hard over into a turn. The Higgins
could turn much tighter than the Elco. As evasive tactics were the single
greatest defense of the PT, it is not surprising that the Higgins crews touted
their maneuverability compared to the Elco boats. Even the steering
arrangements of both designs showed a different philosophy. The Elco had
three small elliptical rudders, while the Higgins used two larger, squared
blades. Although the larger rudders of the Higgins were more effective in
initiating a turn, the tip vortices detracted from high-speed performance and
contributed to stalling.
The topsides of the Higgins 78 are conical in section and show no flare. The
only understandable reason for such a lack of shape points to the prototype,
PT-70. The original boat was noted for its lightweight plywood topsides and
deck, which would require a conical mold. When the 78 was build, it appears
that the topsides were not redrawn to add beam at the forward deck. The result
was that the Higgins was slab sided and would throw spray straight up over the
foredeck and into the cockpit (which was situated well forward). This helm
location was also noted for poor visibility to the sides, as it was flanked
by the machine gun turrets.
The argument of maneuverability versus speed and accommodations still rages
between Elco and Higgins PT veterans. I learned early on in my research that
it wouldn't be a good idea to point out design shortcomings of their own boats,
or attributes of the other boats, to anyone who had fought on either PT.
Variants and Adaptations
The role of the PT gradually evolved, requiring a boat that could cut off enemy
supply lines and reinforcements. The result was that the PTs became armed more
as gunboats than as pure torpedo boats. Whether modified at the factory or
literally strapped on deck by the crew, every manner of mortar, rocket, bazooka,
or cannon was tested to increase firepower. The adapability of the hulls and
their ability to perform even after severe overloading explains why PTs saw
action in every theater.
Higgins continued to refine the torpedo boat concept with its introduction of
the 70'Hellcat later in the war. The new boat reached speeds of 57 mph, and
could reverse direction in a third of the time of its predecessors. Though
certainly the finest small attack craft of the war, the Hellcat was simply
too small and could only act as a pure torpedo boat. The Navy decided against
disrupting current production lines to put the Hellcat into service.
Elco continually modified its boats to maintain performance levels. Two
fascinating innovations were the addition of the Elcoplane and Elco \"slipper.\"
The Elcoplane consisted of a series of wedge-shaped steps that were fastened to
the underbody, a modification that made the boats' top-end speed jump from 42
mph to 56 mph! However, this came at the price of substantial turbulence
when the boat was off plane. The slipper was a set of plywood bottom panels
that extended past the transom. The panels were adjusted up and down with
screws to alter trim and attitude, probably the first set of high-performance
trim tabs.
Epilogue
The Navy was faced with the daunting prospect of mothballing and maintaining
the PT fleet at the end of World War II. With their mission complete, most
of the boats from the Mediterranean were given to the U.S.S.R. under lend-lease,
and the Pacific boats were gathered and torched on the beaches of Samar in the
Philippines. While this seems a particularly tragic end for such charismatic
craft, it only underscores that the boats were indeed expendable.
With their extravagant design and high profile, it is easy to overlook that
one of the greatest assests of the wooden wonders was that they were
inexpensive. For the price of one destroyer, the Navy had been able to build
three full squadrons of PTs (36 boats). Given its relatively low budget, the
PT boat program made a major impact and lasting impression. It serves as a
symbol of the achievement made in mobilizing the labor and resources of the
wooden boat building industry.
The refinement of high-performance V-bottomed hulls continued in the postwar
years, with milestone designs from such names as Huckins, Rybovich, and Ray
Hunt. This development chronicled the scientific approach to studying powerboat
performance and loading. The details of this evolution, as well as its legacy
in naval architecture, ironically have been overshadowed, though the aura of the
PT boat has been enshrined in modern mythology.
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