Editing PT boat (section)

==Development==
At the outbreak of war in August 1914, [[W. Albert Hickman]] devised the first procedures and tactics for employing fast maneuverable seaworthy torpedo motorboats against capital ships, and he presented his proposal to Rear Admiral [[David W. Taylor]], the chief of the US Navy's [[Bureau of Construction and Repair]].<ref name="Article on Albert Hickman">{{cite magazine |url=http://www.woodenboat.com/library-content/woodenboat100.pdf |title=Damned by Faint Praise: The life and hard times of Albert Hickman |author=David Seidman |magazine=WoodenBoat |date=June 1991 |pages=46–57 |access-date=21 April 2016 |archive-date=6 May 2016 |archive-url=https://web.archive.org/web/20160506013837/http://www.woodenboat.com/library-content/woodenboat100.pdf |url-status=dead}}</ref> In September 1914, Hickman completed plans for a {{convert|50|ft|m|adj=on}} [[Hickman sea sled|"Sea Sled" torpedo boat]] and submitted these to the Navy in hopes of obtaining a contract. While favorably received, Secretary of the Navy [[Josephus Daniels]] rejected the proposal since the US was not at war, but Hickman was advised to submit his plans and proposal to the British Admiralty, which was done the following month. The Admiralty found it interesting but thought that "no fast boat of 50' to 60'
length would be sufficiently seaworthy", so Hickman built and launched his own privately financed {{convert|41|ft|m|adj=on}} sea sled capable of carrying a single 18-inch [[Whitehead Mark 5 torpedo]].<ref name="Article on Albert Hickman"/> In February 1915, this Hickman sea sled demonstrated {{convert|35|kn|km/h mph|abbr=on}} speeds in rough winter seas off Boston to both US and foreign representatives, but again he received no contracts. The Admiralty representative for this sea sled demonstration was Lieutenant G. C. E. Hampden.<ref name="Article on Albert Hickman"/> In the summer of 1915, Lieutenants Hampden, Bremner, and Anson approached [[John I. Thornycroft & Company]] about developing a small high speed torpedo boat, and this effort eventually led to the [[Coastal motor boat|Coastal Motor Boat]] which first went into service in April 1916.

Meanwhile, in August 1915, the [[General Board of the United States Navy]] approved the purchase of a single experimental small torpedo boat that could be transportable. This contract for C-250 ended up going to [[Greenport Basin and Construction Company]]. When it was delivered and tested in the summer of 1917, it was not deemed a success, so a second boat (C-378) of the sea sled design was ordered from Hickman in either late 1917 or early 1918 (conflicting dates).<ref name="Article on Albert Hickman"/> Using his previous design from September 1914 and the previous unsuccessful bid for C-250, the C-378 was completed and fully tested just in time to be cancelled as a result of the [[Armistice of 11 November 1918|Armistice]]. With a full loaded weight of {{cvt|56,000|lb}}, C-378 made a top speed of {{convert|37|kn|km/h mph|abbr=on}} with {{convert|1400|hp}}, and maintained an average speed of {{convert|34.5|kn|km/h mph|abbr=on}} in a winter northeaster storm with {{convert|12|to|14|ft|m|adj=on}} seas, which would still be considered exceptional even 100 years later.{{Fact|date=May 2025}}

The sea sled did not surface again as a torpedo boat topic until 1939 but continued to be used by both the Army and Navy as rescue boats and seaplane tenders during the 1920s and 1930s. In 1922, the US Navy reconsidered using small internal combustion engine powered torpedo boats. As a result, two types—{{convert|45|ft|m|adj=on}} and {{convert|55|ft|m|adj=on}}—of British Royal Navy Coastal Motor Boats were obtained for testing.<ref>{{cite magazine |url=https://books.google.com/books?id=NNoDAAAAMBAJ&pg=PA497 |title=Navy Acquires Small Speedy Torpedo Boats |date=October 1922 |magazine=[[Popular Mechanics]] |pages=497–498 |publisher=Hearst Magazines}}</ref> The larger boat was used for experiments until 1930. In 1938, the US Navy renewed their investigation into the concept by requesting competitive bids for several different types of motor torpedo boats but excluded Hickman's sea sled.<ref name="Article on Albert Hickman" /> This competition led to eight prototype boats built to compete in two different classes. The first class was for {{convert|54|ft|m|adj=on}} boats, and the second class was for {{convert|70|ft|m|adj=on}} boats. The resulting PT boat designs were the product of a small cadre of respected naval architects and the Navy.

===Design competition===
On 11 July 1938 the Navy solicited design proposals for four separate types of boat: a 165-foot subchaser, a 110-foot subchaser, a 70-foot motor torpedo boat, and a 54-foot motor torpedo boat.<ref name="Bulkley p44">Bulkley, 1962 p44</ref>
The winning design proposals would each receive a prize of $15,000 with $1,500 for designs that reached the final part of the competition each to be given out on 30 March 1939.

The larger boat proposal was not to exceed 80 feet and was to carry at least two 21-inch torpedoes, four depth charges, and two .50-cal machine guns. The performance specification was to achieve 40 knots with an operating radius of 275 miles at top speed (550 miles at cruising speed). The smaller boat proposal was to weigh no more than 20 tons so that it could be easily transported by larger cargo ships. Its maximum top speed was also to be 40 knots, but specified operating radius was to be 120 miles at top speed and 240 miles at cruising speed. Equipped armament for the smaller proposal was to be either two torpedoes and two depth charges, or .50-cal machine guns and a smokescreen generator.<ref name="Bulkley p44"/>

By September 1938 the U.S. Navy had received 24 design proposals for the small boat and 13 design proposals for the larger 70-footer. Of those proposals submitted, three 54-ft designs and five 70-ft designs were of interest, and the designers were asked to submit more detailed plans for both the 54 and 70 foot boats by no later than 7 November.<ref name="Bulkley p44"/> On 21 March 1939 [[Sparkman & Stephens]] won the prize in the 70-foot class, and [[George Crouch]] (for [[Henry B. Nevins, Incorporated|Henry B. Nevins, Inc.]]) had won the design proposal for the 54-foot class.<ref name="Bulkley p44"/> After winning the design competition for the smaller PT boat, Crouch wrote that Hickman's sea sled design would be far superior "in either rough or smooth water to that of the best possible V-bottom or hard chine design". Earlier when sea sleds were specifically excluded, Crouch had informed the Bureau of Ships that the sea sled was the best type of vessel for the job.

[[File:PT-9 torpedo boat Washington DC 1940.jpg|thumb|''PT-9'' in June 1940]]

Following the competition, contracts were placed for construction of boats: 25 May 1939 to [[Higgins Industries]] for two boats (PT5 and PT6) of the Sparkman & Stephens design, scaled up to an overall length of 81 feet; 8 June 1939 to [[Miami Shipbuilding]] (PT-1 and PT-2) and [[Fisher Boatworks]] (PT-3 and PT-4) for the Crouch design; to the [[Philadelphia Navy Yard]] (PT-7, PT-8) for 81-foot boats designed by the Bureau of Ships.<ref>Bulkley p44-45</ref> These last two boats were constructed mainly out of aluminum and had 4 engines. Higgins built an additional ''PT-6 "Prime"'' redesigned by Andrew Higgins personally using his own methods. Later that same year, Higgins built ''PT-70'' (at their own expense) that incorporated slight improvements over ''PT-6 Prime''.

Later, testing revealed shortcomings that had to be fixed before the designs could meet performance specifications. As a result, the Navy ordered further investigation and refinement of the existing designs until a satisfactory working design could be obtained. At the same time, Henry R. Sutphen of [[Electric Launch Company]] (Elco) and his designers (Irwin Chase, Bill Fleming, and Glenville Tremaine) visited the United Kingdom in February 1939 at the Navy's request to see British motor torpedo boat designs with a view to obtaining one that could be used as a check on the Navy's efforts. While visiting the [[British Power Boat Company]], they purchased a {{convert|70|ft|m|adj=on}} private venture [[motor torpedo boat]] (MTB) design—PV70, later renamed ''PT-9—''designed by the power boat racer [[Hubert Scott-Paine]]. ''PT-9'' was to serve as the prototype for all the early Elco PT boats. After the initial competition, in late 1939 the Navy contracted Elco to build 11 copies of ''PT-9''.<ref name="Bulkley p44" />

On 11 October 1940 an agreement between the Navy and [[Huckins Yacht Corporation]] was finalized. The Navy would provide engines and Huckins would build a PT boat at their own expense, with the caveat that the boat (upon completion) would be offered to the Navy for a later sum. This {{convert|72|ft|m|adj=on}} boat (designated MT-72) later became ''PT-69''. Huckins reported a profit of $28.60 on this transaction.<ref>Frank Huckins,''Address Before the Great Lakes Cruising Club'', Chicago (21 April 1944) contained in ''Huckins, The Living Legacy''</ref>

===Plywood Derby===
====Background====
In March 1941, during a heavy weather run from [[Key West]] to New York by Motor Torpedo Boat Squadron 2 (MTBRON&nbsp;2), Elco 70-footers pounded heavily in {{convert|8|to|10|ft|m|adj=on}} waves even at moderate speeds, and seas continuously broke high over the bows. Operating personnel reported extreme discomfort and fatigue. All boats suffered from some sort of structural failure: forward chine guards ripped away, bottom framing under bows broken, side planking cracked [indicating lack of longitudinal strength], and other weaknesses were reported. In April MTBRON&nbsp;1 reported enthusiasm over the 81-foot Higgins (''PT-6''), and with the ''PT-6'' showing such good seakeeping, further purchase of Scott-Paine boats was unnecessary. In early 1941 the [[U.S. Navy Bureau of Ships]] lent Packard engines to both Huckins and Higgins, which wanted to build competitive boats at their own expense.

A Chief of Naval Operations PT Boat Conference convened in May 1941 to discuss future PT characteristics. All PTs prior to the {{convert|77|ft|abbr=on}} Elcos had been found defective, and it was probable the extended {{convert|70|ft|abbr=on}} Elco would not be an improvement. The conference recommended a series of comparative tests to evaluate what turned out to be five new designs of motor torpedo boats. The conference strongly recommended that no more Elco 77-footers be ordered until the tests had shown that they were indeed satisfactory.<ref>The Chief of Naval Operations,''Report of Conference on Motor Torpedo Boats'', Op-23D-KM, PT/S1(410414)Serial 181923 (Navy Department, 17 June 1941)</ref>

====Board of Inspection and Survey====
The [[Board of Inspection and Survey]], headed by Rear Admiral [[John W. Wilcox Jr.]], conducted comparative service tests<ref name=board>Board of Inspection and Survey, ''Report of Comparative Services Tests of Motor Torpedo Boats Held July 21–24, 1941 and August 11–12, 1941 at New London, Connecticut'' (Navy Department, August 14, 1941)</ref> off [[New London, Connecticut]], from 21 to 24 July 1941, using the following boats:

* ''PT-6'': {{convert|81|ft|m|adj=on|abbr=on}} Higgins; 3 Packard {{convert|1200|hp|abbr=on}} engines.
* ''PT-8'': {{convert|81|ft|m|adj=on|abbr=on}} Philadelphia Navy Yard; aluminum hull; 2 [[Allison Engine Company|Allison]] {{convert|2000|hp|abbr=on}} engines, 1 [[Hall-Scott]] {{convert|550|hp|abbr=on}} engine.
* ''PT-20'': {{convert|77|ft|m|adj=on|abbr=on}} Elco; 3 Packard {{convert|1200|hp|abbr=on}} engines; equipped with special propellers; special strengthening added to hull framing and deck.
* ''PT-26'', ''-30'', ''-31'', ''-33'': Same as ''PT-20'', except with standard propellers and without special strengthening.
* ''PT-69'': {{convert|72|ft|m|adj=on|abbr=on}} Huckins; 4 Packard {{convert|1200|hp|abbr=on}} engines.
* ''PT-70'': {{convert|76|ft|m|adj=on|abbr=on}} Higgins; 3 Packard {{convert|1200|hp|abbr=on}} engines.
* One {{convert|70|ft|m|adj=on|abbr=on}} MRB-8 (Motor Rescue Boat), built for the [[Royal Navy]] by Higgins; 3 Hall-Scott {{convert|900|hp|abbr=on}} engines.

Each member of the board conducted an independent inspection of every boat class, evaluating them for structural sufficiency, habitability, access, arrangement for attack control, and communication facilities.<ref name=board /> Boats were also evaluated under two conditions of armament loading: loaded and fully equipped with four {{convert|21|in|cm|abbr=on}} torpedoes and sufficient fuel to operate 500 NM at 20 knots; and fully loaded with two {{convert|21|in|cm|abbr=on}} torpedoes and ten {{convert|300|lb|abbr=on}} depth charges with sufficient fuel to operate {{convert|500|nmi|km smi|abbr=on}} at {{convert|20|kn|km/h mph|abbr=on}}.<ref name="board" /> Boats would have their tactical parameters of each design determined by photographs from an airship.<ref name="board" />

=====First open-ocean trial=====
Lastly, there was a demonstration of seakeeping qualities and hull strength by making a run at maximum sustained speed in the open ocean. An accelerometer was installed in the [[pilot house]] of each boat to record "pounding". Conducted on 24 July 1941, this open-water trial, {{convert|190|nmi|km smi|abbr=on}} at full throttle, was referred to by PT personnel as the "Plywood Derby". The course started from the mouth of New London Harbor, to Sarah Ledge, then led around the eastern end of [[Block Island]], then around Fire Island Lightship, finishing at [[Montauk, New York|Montauk Point]] Whistling Buoy.<ref name=board />

At the time, only the Elco 77-footers were loaded with armament. The other competitors had copper ingots added topside (mostly in the turrets) to make up the difference. This resulted in severe conditions for several of the boats during the trial and accounted for the transverse failure in ''PT-70''{{'}}s deck and subsequent hull failure as the copper fell into the hull.<ref name=board /> Nine boats participated in the trial.<ref group="note">''PT-26'' had previously developed deck failures while conducting standardization trials off Block Island on 21 July 1941.</ref> Six boats completed the trial, while three withdrew: ''PT-33'' suffered structural damage off Block Island; ''PT-70'' was damaged by loose copper ingots; and ''MRB'' developed engine trouble at the start of the run.<ref name="board" />

By class, ''PT-20'', an Elco 77-footer, came in first with an average speed of {{convert|39.72|kn|km/h mph|abbr=on}}; followed by ''PT-31'', with an average speed of {{convert|37.01|kn|km/h mph|abbr=on}}; ''PT-69'', the Huckins {{convert|72|ft|m|adj=on}} boat, was third with an average speed of {{convert|33.83|kn|km/h mph|abbr=on}};<ref group=note>The Huckins boat experienced a high pressure oil failure and had to go "Dead in the Water" in order to effect the repair.</ref> ''PT-6'', the Higgins 81-footer, with an average speed of {{convert|31.4|kn|km/h mph|abbr=on}} was fifth; and ''PT-8'', the Philadelphia Navy Yard boat, was last, at {{convert|30.75|kn|km/h mph|abbr=on}}. The other two Elco boats, ''PT-30'' and ''PT 23'' (standby boat), followed ''PT-31'', placing before ''PT-69''.

[[File:PT-31 crossing the "Plywood Derby" finish line at Montauk Point, Long Island, 24 July 1941.jpg|thumb|Second place PT-31 crossing the finish line during the "Plywood Derby".]]

The accelerometers ranked the boats as follows: first was the Philadelphia Navy Yard ''PT-8'' with the least pounding, second was the Huckins ''PT-69'', third was the Higgins ''PT-6'', and last were the Elco 77-footers.<ref name=board />

=====Second open-ocean trial=====
Because of the problem with ingot loading, a {{convert|185|nmi|km smi|abbr=on}} trial with the PTs fully fitted out was conducted on 12 August 1941. Four boats—''PT-8'', ''PT-69'', ''PT-70'', and MRB—returned and Elco sent two new boats, ''PT-21'' and ''PT-29''. During this trial, boats faced heavier seas, as high as {{convert|16|ft|abbr=on}}. All except the Huckins (''PT-69'') completed the run. The Huckins withdrew because of a bilge stringer failure. The Higgins 76-footer (''PT-70'') completed the entire run but also suffered structural failures: attachments between planking and web frames pulled loose and deck fastenings near engine hatches showed extensive failures. ''PT-21'' suffered minor cracks in the deck in the same location, but not to the same extent, as previously observed in ''PT-26'', ''PT-30'', and ''PT-33''. ''PT-29'' was assigned as a pace boat with ''PT-8'' in order to generate a pounding comparison.<ref name=board />

The average speed results from the {{convert|185|nmi|km smi|abbr=on}} course were: Elco 77-footer (''PT-21''), {{convert|27.5|kn|km/h mph|abbr=on}}; Higgins 76-footer (''PT-70''), {{convert|27.2|kn|km/h mph|abbr=on}}; Higgins MRB and Philadelphia Navy Yard boat (''PT-8''), {{convert|24.8|kn|km/h mph|abbr=on}}. Accelerometers were again installed in the pilot house of each boat, but the readings were incomplete because the violent motion of the boats made observations difficult and in some cases necessitated abandonment of the observing stations. Further, many of those taken were beyond the normal range of the instruments and were considered inaccurate. Elco boats were found to pound heavily and confirmed previous reports of crew discomfort.<ref name=board />

====Findings====
The Elco 77-Footer Design Demonstrates:<ref name=board />
# Ability to make a maximum sustained speed of 39.7 knots; maximum speed 44.1 knots with heavy ordnance load.
# Maneuverability satisfactory except for a large turning circle of {{convert|432|yd}}.
# Space available for four 21" torpedo tubes.
# Structural weaknesses resulting in transverse fractures of deck planking.
# Tendency to pound heavily in a seaway.
# Fittings and finish unnecessarily refined.
# Cost to the Government fully equipped $302,100.

The Huckins 72-Foot Design Demonstrates:<ref name=board />
# Ability to make a maximum sustained speed of 33.8 knots; maximum speed 43.8 knots with light ordnance load.
# Maneuverability satisfactory with a turning circle of {{convert|336|yd}}.
# Space available for two 21" torpedo tubes and ten {{convert|300|lb|kg|adj=on}} depth charges.
# Structural weaknesses resulting in fracture of bilge stringers.
# Very little tendency to pound in a seaway.
# Fittings and finish appropriate for a motor torpedo boat.
# Cost to the Government fully equipped $263,500.

The Navy Yard Philadelphia 81-Foot Design Demonstrates:<ref name=board />
# Ability to make a maximum sustained speed of 30.7 knots; maximum speed 33.9 knots with light ordnance load.
# Maneuverability unsatisfactory due to inability to reverse outboard engines with a large turning circle of {{convert|443|yd}}
# Space available for two 21" torpedo tubes and ten {{convert|300|lb|kg|adj=on}} depth charges.
# Structural strength is adequate.
# Tendency to pound severely in a seaway.
# Fittings (Navy standard for combatant ships) entirely too heavy and cumbersome for this type of craft. Finish adequate.
# Cost to the Government fully equipped $756,400.

The Higgins 81-Foot Design Demonstrates:<ref name=board />
# Ability to make a maximum sustained speed of 31.4 knots; maximum speed 34.3 knots with heavy ordnance load.
# Maneuverability satisfactory with a turning circle of 368 yards.
# Space available for four 21" torpedo tubes.
# Structural strength adequate.
# Moderate tendency to pound in a seaway.
# Fittings and finish satisfactory.
# Cost to the Government fully equipped $206,600.

The Higgins 76-Foot Design Demonstrates:<ref name=board />
# Maximum sustained speed of 27.2 knots in rough seas; maximum speed 40.9 knots.
# Maneuverability satisfactory, turning circle not determined photographically, estimated 300 yards.
# Space available for four 21" torpedo tubes.
# Structural weaknesses caused failures in transverse bottom framing, separation of side planking from framing and extensive failures of deck fastenings.
# Moderate tendency to pound in a seaway.
# Fittings and finish satisfactory.
# Cost to the Government fully equipped $265,500.

The board arrived at the following recommendations:<ref name=board />
# That the Packard power plant having been found highly satisfactory be adopted as standard for future construction.
# That the ordnance installation of future motor torpedo boats consist of two torpedo tubes, machine guns and depth charges.
# That the Huckins 78-foot (''PT-69'') design be considered acceptable for immediate construction.
# That the Higgins 80-foot (''PT-6'') design suitably reduced in size to carry such ordnance loads as are required by our Navy be considered acceptable for immediate construction.
# That the Elco 77-foot design be considered acceptable for future construction provided changes in the lines are made to reduce the tendency to pound in a seaway, and the structure be strengthened in a manner acceptable to the Bureau of Ships.
# That the Philadelphia 81-foot boat (''PT-8''') be stripped of excess weight and be re-engined with three Packard engines.

The board also had the following opinion on structural sufficiency: "During the first series of tests (21–24 July) the Huckins design (PT-69), the Philadelphia design (PT-8) and the Higgins design (PT-6) completed the open sea endurance run without structural damage. The Higgins 70' (British) boat did not complete this run because of engine trouble. The Higgins 76' (PT-70) and boats of the Elco 77' (PT-20 Class) developed structural failures even under moderate weather conditions prevailing. In the interval between the first and second test periods the PT-70 was repaired and an effort made to eliminate the causes of the structural failures. However, during the second endurance run, which was made in a very rough sea for this size boat, structural failures again occurred in PT-70. PT-69 and PT-21 experienced structural failures during the second run though these were much more localized as compared with those found on PT-70. The Board is of the opinion that certain changes in design are required to enable PT-69 and boats of the PT-20 Class to carry safely their military loads in rough weather."<ref name=board />

The board results provided very important benchmarks in the infancy of PT boat development.{{citation needed|date=June 2020}} This type of craft presented design challenges that were still issues decades after, but there are some significant conclusions from the above recommendations and their order of merit. Those are:<ref name=board />

# The Packard were the engines of choice.
# The Huckins 72-foot (''PT-69'') and a reduced Higgins 81-foot (''PT-6'') design were to be placed into production. Following an October 1941 BuShips conference and its new set of navy design requirements which included room to support four {{convert|21|in|cm|abbr=on}} torpedoes and an upper length restriction of 82', the next two orders for pre-war PT boats (''PT-71'' through ''PT-102'') were awarded to Higgins and Huckins.
# Even though the Elco 77-footers posted the fastest speeds, all seven Elcos suffered from structural damage and severe pounding causing the Board to recommend a redesign to correct these deficiencies. Elco competed for the ''PT-71'' to ''PT-102'' contract but did not win due to their higher unit price. After the start of the war and significantly revising their unit cost, Elco received the next PT boat order after Higgins and Huckins. This was to be their new Elco 80-foot design.

[[File:ELCO and Higgins PT boats, Know Your PT Boat US Navy July 1945.jpg|thumb|upright|Elco and Higgins PT boats, as published in a 1945 training manual]]

===Elco===
The newly designed {{convert|80|ft|m|adj=on|abbr=on}} [[Electric Launch Company#History|Elco Naval Division]] boats were the longest of the three types of PT boats built for the Navy used during World War II. By war's end, more of the Elco boats were built (326 in all) than any other type of motor torpedo boat. While comparable in size to many wooden sailing ships in history, these {{convert|20|ft|8|in|m|adj=on|abbr=on}} [[Beam (nautical)|beam]] wooden-[[Hull (watercraft)|hulled]] craft were classified as boats in comparison with much larger steel-hulled [[destroyer]]s, [[destroyer escort]]s, and [[corvette]]s. Five Elco boats were manufactured in [[knock-down kit]] form and sent to Long Beach Boatworks for assembly on the West Coast as part of an experiment and as a proof of concept.

===Higgins===
Higgins Industries produced 199 {{convert|78|ft|m|adj=on|abbr=on}} boats of the ''[[PT-71]]''/''PT-235'', ''PT-265'' and ''PT-625'' classes. The Higgins boats had the same beam, full load displacement, engines, generators, shaft horsepower, trial speed, armament, and crew accommodation as the {{convert|80|ft|m|adj=on|abbr=on}} Elco boats. Many Higgins boats were sent to the Soviet Union and Great Britain at the beginning of the war, so many of the lower-numbered squadrons in the U.S. Navy were made up exclusively of Elcos. U.S. Navy PT boats were organized into MTBRONs. The first Higgins boats for the U.S. Navy were used in the [[Aleutian Islands campaign|battle for the Aleutian Islands]] (Attu and Kiska) as part of Squadrons 13 and 16, and others (MTBRON15 and MTBRON22) in the Mediterranean against the Germans. They were also used during the [[Normandy landings|D-Day landings]] on 6 June 1944.

Even though only half as many Higgins boats were produced, far more survive (seven hulls, three of which have been restored to their World War II configuration) than the more numerous Elco boats. Of the Elco boats, only three hulls (one restored) were known to exist as of 2016.

===Huckins Yacht Corporation===
[[File:PT boat underway near Midway c1942.JPG|thumb|left|Huckins  {{convert|78|ft|m|adj=on}} ''PT-259'' underway near [[Midway Atoll|Midway]] c.1944]]

Huckins and his innovative Quadraconic planing hull design were latecomers to PT boat design. Not invited to participate in the original design competition, by late 1940, Huckins had a meeting with Captain James M. Irish, Chief of Design, and offered to build a "planing seagoing hull" PT boat, on the condition the Navy loan Huckins engines and agree to look at the Huckins boat. In early July 1941, the Navy accepted ''PT-69''.

After obtaining excellent testing results at the Plywood Derby, the Navy awarded Huckins Yacht Corporation a contract in 1941 for 8 boats, and later added 10 more. The design was enlarged and modified to meet the new requirements. The first three of the new design (''PT-95'' through ''PT-97'') were initially kept in the Jacksonville, Florida, area for testing, resulting in several important modifications to the overall design (these boats were later assigned to Squadron 4 in 1942).

Huckins ended up building just two squadrons of PT boats during World War II. Five {{convert|78|ft|m|adj=on}} boats were assigned to Squadron 14 (''PT-98'' through ''PT-102'') which was commissioned in early 1943; and ten boats assigned to Squadron 26 (PT-255 thru PT-264) which was commissioned in mid 1943.  They were assigned to specific outposts in the [[Panama Canal Zone]], [[Miami, Florida]], the [[Hawaiian Sea Frontier]] at [[Pearl Harbor PT Boat Base|Pearl Harbor]] and Midway, and a [[Melville Motor Torpedo Boat Squadrons Training Center]].

Although not used in any other PT boat design, Huckins licensed the use of his patented Quadraconic hull in his PT boat construction. He also granted permission for Elco, Higgins, and the Philadelphia Navy Yard to use his patented laminated keel, which increased hull strength, although neither Elco nor Higgins chose to use it on their boats. Most probably due to the lateness in joining the PT boat program and unlike Elco and Higgins, the Huckins yard was not provided government support to construct a larger facility prior to the war. The handcrafted Huckins PT was produced at their civilian facility at a speed of one per month. The success and ruggedness of the Huckins' 78-foot seagoing design is demonstrated by Squadron 26's constant ready-boat operations and fleet torpedo boat training in the oceans around [[Midway Atoll|Midway]] and [[Hawaii]] during the last two years of the war.

===Vosper and other types of PT boats===
[[Vosper & Company|Vospers]] of Great Britain arranged for several boatyards in the United States to build British-designed {{convert|70|ft|m|adj=on|abbr=on}} motor torpedo boats under license to help the war effort. The boatyards were located in [[Annapolis Yacht Yard|Annapolis]], [[Herreshoff Manufacturing Company|Bristol]], [[Robert Jacob Shipyard|City Island]], [[Miami Shipbuilding|Miami]], and [[Harbor Boat Building Company|Los Angeles]]. 146 boats, armed with {{convert|18|in|mm|adj=on|abbr=on}} torpedoes, were built for [[Lend Lease]], and exported to Allied powers such as Canada, Britain, Norway, and the Soviet Union. These boats were never used by the U.S. Navy, and only about 50 were used by the [[Royal Navy]]; most were passed to other countries. The [[Canadian Power Boat Company]] produced four Scott-Paine designed PTs for the U.S. These were to be provided to the Dutch forces under Lend Lease but were re-requisitioned to the USN as PT 368–371 after the fall of the Netherlands to German forces.