Editing PT boat (section)

==Construction==
PT boats offered accommodation for three officers and 14 enlisted men.  Crews varied from 12 to 17, depending upon the number and type of weapons installed. Full-load displacement late in the war was 56 tons.

The hull shapes of the Elco and Higgins PT boats were similar to the contoured "planing hull" found in pleasure boats of the time (and still in use today): a sharp V at the bow softening to a flat bottom at the stern. A common characteristic of this type of contoured hull is the "rooster tail" in the wake. Unlike the actual "planing hull" Huckins, which planed at 10-11 knots, the Elco and Higgins PT boats were intended to plane at higher speeds (PT 71 and PT-103 classes at around 27 knots, and the PT-265 and 625 classes at around 23 knots).

The Elco, Higgins and Huckins companies used varying lightweight techniques of hull construction. Though often said to be made of [[plywood]], the hulls were actually made of two diagonal layered {{convert|1|in|mm|adj=on|abbr=on}} thick [[mahogany]] planks, with a glue-impregnated or lead-painted layer of canvas in between. Holding all this together were thousands of bronze screws and copper rivets. This type of construction made it possible for damage to the wooden hulls of these boats to be easily repaired at forward operating bases by base force personnel.  According to Robert McFarlane, the US Navy built the hulls of some PT boats partially from 3,000-year-old white cedar logs recovered from sphagnum bogs in New Jersey.<ref>Robert McFarlane. The Wild Places. 2008. p. 74</ref><ref>{{Citation |title=Giant Killers (Full Version) The Elco PT Boat |url=https://www.youtube.com/watch?v=x_w8ssx3hSU |access-date=2023-05-25 |language=en |archive-date=20 September 2022 |archive-url=https://web.archive.org/web/20220920011709/https://www.youtube.com/watch?v=x_w8ssx3hSU&gl=US&hl=en |url-status=live}}</ref>

[[File:NH 64787-KN crop.tiff|thumb|USS ''PT-167'' is holed by an enemy torpedo that failed to detonate, 5 November 1943.  Painting by [[Gerard Richardson]]<ref>{{cite web|title=NH 64787-KN|url=https://www.history.navy.mil/our-collections/photography/numerical-list-of-images/nhhc-series/nh-series/NH-64000/NH-64787-KN.html|website=[[Naval History and Heritage Command]]|publisher=[[United States Navy]]|access-date=27 April 2016|archive-date=26 May 2019|archive-url=https://web.archive.org/web/20190526192448/https://www.history.navy.mil/our-collections/photography/numerical-list-of-images/nhhc-series/nh-series/NH-64000/NH-64787-KN.html|url-status=live}}</ref>]]

As a testament to the strength of this type of construction and watertight bulkheads, several PT boats withstood catastrophic battle damage and still remained afloat. For example, the forward half of future President [[John F. Kennedy]]'s ''[[PT-109]]'' (Elco) stayed afloat for 12 hours after she was cut in half by the Japanese destroyer [[Japanese destroyer Amagiri (1930)|''Amagiri'']]. ''PT-323'' (Elco) was cut in half by a ''[[kamikaze]]'' aircraft on 10 December 1944 off [[Leyte]], yet remained floating for several hours. ''PT-308'' (Higgins) had her stern sheared off by a collision with ''PT-304'' during a night mission in the Mediterranean on 9 March 1945 and yet returned to base for repairs. ''PT-167'' (Elco) was holed through the bow off [[Bougainville Island]] on 5 November 1943 by a torpedo which failed to detonate; the boat remained in action and was repaired the next day.

In 1943, an inquiry was held by the Navy to discuss planing, hull design, and fuel consumption issues. This resulted in the November 1943 Miami test trial between two Higgins and two Elco boats, but no major additional modifications were made before the end of the war. During the war, Elco came up with stepped hull designs ("ElcoPlane") which achieved significant increase in top speed. Higgins developed the small and fast {{convert|70|ft|m|adj=on}} ''Higgins Hellcat'', which was a slight variation on their original hull form, but the Navy rejected them for full production because of increased fuel consumption and other considerations.{{citation needed|date=May 2017}}

After the war, Lindsay Lord, who was stationed in Hawaii during the war, recorded the Navy's planing hull research and findings in ''Naval Architecture of Planing Hulls''. It covers PT boat hull design and construction and provides hull test data as well as detailed analysis of the various PT boat designs.<ref>Lindsay Lord, ''Naval Architecture of Planing Hulls'' (Cornell Maritime Press, 1946)</ref>