View source for USS Pennsylvania (BB-38)

{{Short description|Dreadnought battleship of the United States Navy}}
{{Other ships|USS Pennsylvania}}
{{Use shortened footnotes|date=October 2022}}
{{good article}}
{{Use dmy dates|date=October 2021}}
{|{{Infobox ship begin}}
{{Infobox ship image
| Ship image = [[File:USS Pennsy BB-38 1934.jpg|300px|USS Pennsylvania, 31 May 1934]]
| Ship caption = USS ''Pennsylvania'' under way off [[New York City]] on 31 May 1934
}}
{{Infobox ship career
| Hide header =
| Ship country = United States
| Ship flag = {{USN flag|1948}}
| Ship name = ''Pennsylvania''
| Ship namesake =  [[Pennsylvania]]
| Ship ordered = 22 August 1912
| Ship builder = [[Newport News Shipbuilding|Newport News Shipbuilding and Drydock Company]]
| Ship laid down = 27 October 1913
| Ship launched = 16 March 1915
| Ship commissioned = 12 June 1916
| Ship decommissioned = 29 August 1946
| Ship struck = 19 February 1948
| Ship fate = Scuttled off [[Kwajalein Atoll]] after [[Operation Crossroads]] on 10 February 1948
}}
{{Infobox ship characteristics
| Hide header =
| Header caption=(as built)
| Ship class = {{sclass|Pennsylvania|battleship}}
| Ship displacement = [[Full load]]: {{convert|31917|LT|MT}}
| Ship length = {{convert|608|ft|m|abbr=on}}
| Ship beam = {{convert|97.1|ft|m|abbr=on}}
| Ship draft = {{convert|28.9|ft|m|abbr=on}}
| Ship propulsion =
*4 × Curtis ungeared/Westinghouse [[steam turbine]]s
*4 × [[screw propeller]]s
| Ship power=
*12 × [[Babcock & Wilcox]] [[water-tube boiler]]s
*{{convert|34000|shp|kW|abbr=on|lk=in}}
| Ship speed = {{convert|21|kn|mph km/h|abbr=on}}
| Ship range = {{convert|7552|nmi|mi km|abbr=on}} at {{convert|12|kn|mph km/h|abbr=on}}
| Ship capacity = Fuel oil: {{convert|2305|LT|t|0}}
| Ship complement =
* 56 officers
* 72 Marines
* 1,031 enlisted men
| Ship armament =
* 12 × [[14"/45 caliber gun|{{convert|14|in|0|abbr=on}}/45 cal guns]] (4×3)
* 22 × [[5"/51 caliber gun|{{convert|5|in|0|abbr=on}}/51 cal guns]]
* 4 × [[3"/50 caliber gun|{{convert|3|in|mm|abbr=on}}/50 cal anti-aircraft guns]]
* 2 × submerged [[American 21 inch torpedo|21 inch (533 mm)]] [[torpedo tube]]s
| Ship armor =
* [[Belt armor|Belt]]: {{convert|13.5|in|mm|abbr=on}}
* [[Deck (ship)|Deck]]: {{convert|3|in|mm|abbr=on}} (ends)
* [[Gun turret|Turrets]]: {{convert|18|in|mm|abbr=on}} (faces)
* [[Conning tower|Conning Tower]]: {{convert|16|in|mm|abbr=on}}
| Ship aircraft = 2 × [[floatplane]]s
| Ship aircraft facilities = 2 × [[Aircraft catapult|catapults]]
}}
{{Infobox ship characteristics
|Header caption=(1931)
| Ship displacement = 
*Standard: {{convert|34400|LT|t|0|abbr=on}}
*Full load: {{convert|39224|LT|t|0|abbr=on}}
| Ship power = 6 × Bureau Express boilers
| Ship armament =
* 12 × 14"/45 cal guns (4×3)
* 12 × 5"/51 cal guns
* 8 × [[5-inch/25-caliber gun|5"/25 cal anti-aircraft guns]]
* 8 × [[M2 Browning|.50-cal M2 Browning]] machine guns
}}
{{Infobox ship characteristics
|Header caption=(1942)
| Ship sensors = [[CXAM radar|CXAM-1 radar]]
| Ship armament =
* 12 × 14"/45 cal guns (4×3)
* 16 × [[5-inch/38-caliber gun|5"/38 cal guns]]
* 40 × [[Bofors 40 mm Automatic Gun L/60|{{cvt|40|mm}} Bofors guns]]
* 51 × [[Oerlikon 20 mm cannon#World War II|{{cvt|20|mm}} Oerlikon guns]]
}}
|}

'''USS ''Pennsylvania'' (BB-38)''' was the lead ship of the {{sclass|Pennsylvania|battleship|4}} of [[Dreadnought#Super-dreadnoughts|super-dreadnought]] [[battleship]]s built for the [[United States Navy]] in the 1910s. The ''Pennsylvania''s were part of the [[standard-type battleship]] series, and marked an incremental improvement over the preceding {{sclass|Nevada|battleship|4}}, carrying an extra pair of {{convert|14|in|adj=on|0}} guns for a total of twelve guns. Named for the Commonwealth of [[Pennsylvania]], she was [[keel laying|laid down]] at the [[Newport News Shipbuilding|Newport News Shipbuilding and Drydock Company]] in October 1913, was [[ship launching|launched]] in March 1915, and was [[ship commissioning|commissioned]] in June 1916. Equipped with an oil-burning propulsion system, ''Pennsylvania'' was not sent to European waters during [[World War I]], since the necessary [[fuel oil]] was not as readily available as coal. Instead, she remained in American waters and took part in training exercises; in 1918, she escorted President [[Woodrow Wilson]] to France to take part in peace negotiations.

During the 1920s and 1930s, ''Pennsylvania'' served as the [[flagship]] of first the [[United States Fleet Forces Command|Atlantic Fleet]], and after it was merged with the [[United States Pacific Fleet|Pacific Fleet]] in 1921, the [[Battle Fleet]]. For the majority of this period, the ship was stationed in California, based in [[San Pedro, Los Angeles|San Pedro]]. ''Pennsylvania'' was occupied with a peacetime routine of training exercises (including the annual [[Fleet problem]]s), port visits, and foreign cruises, including a visit to Australia in 1925. The ship was modernized in 1929–1931. The ship was present in [[Pearl Harbor]] on the morning of 7 December 1941; she was in drydock with a pair of [[destroyer]]s when the Japanese launched [[Attack on Pearl Harbor|their surprise attack on the port]]. She suffered relatively minor damage in the attack, being protected from torpedoes by the drydock. While repairs were effected, the ship received a modernized anti-aircraft battery to prepare her for operations in the [[Pacific War]].

''Pennsylvania'' joined the fleet in a series of amphibious operations, primarily tasked with providing gunfire support. The first of these, the [[Aleutian Islands Campaign]], took place in mid-1943, and was followed by an [[Battle of Makin|attack on Makin]] later that year. During 1944, she supported the [[Battle of Kwajalein|landings on Kwajalein]] and [[Battle of Eniwetok|Eniwetok]] in the [[Marshall Islands]] and the [[Mariana and Palau Islands campaign]], including the [[Battle of Saipan|Battles of Saipan]], [[Battle of Guam (1944)|Guam]], [[Battle of Peleliu|Peleliu]], and [[Battle of Angaur]]. During the [[Philippines campaign (1944–1945)|Philippines campaign]], in addition to her typical shore bombardment duties, she took part in the [[Battle of Surigao Strait]], though due to her inadequate radar, she was unable to locate a target and did not fire. During the [[Battle of Okinawa]], she was torpedoed by a Japanese [[torpedo bomber]] and badly damaged, forcing her to withdraw for repairs days before the end of the war.

Allocated to the [[target ship|target fleet]] for the [[Operation Crossroads]] nuclear tests in 1946, ''Pennsylvania'' was repaired only enough to allow her to make the voyage to the test site, [[Bikini Atoll]]. She survived both blasts, but was badly contaminated with radioactive fallout from the second test, and so was towed to [[Kwajalein]], where she was studied for the next year and a half. The ship was ultimately [[scuttling|scuttled]] in deep water off the atoll in February 1948.

== Description ==
{{main|Pennsylvania-class battleship}}
[[File:USS Pennsylvania (BB-38) drawing 1943.PNG|thumb|left|Line drawing of ''Pennsylvania'' as she appeared following her 1942 reconstruction]]

Part of the [[standard-type battleship]] series, the ''Pennsylvania''-class ships were significantly larger than their predecessors, the {{sclass|Nevada|battleship|4}}. ''Pennsylvania'' had an [[length overall|overall length]] of {{convert|608|ft}}, a [[beam (nautical)|beam]] of {{convert|97|ft}} (at the [[waterline]]), and a [[draft (ship)|draft]] of {{convert|29|ft|3|in|m}} at [[deep load]]. This was {{convert|25|ft|m}} longer than the older ships. She [[displacement (ship)|displaced]] {{convert|29158|LT|MT}} at [[Displacement (ship)|standard]] and {{convert|31917|LT|MT}} at deep load, over {{convert|4000|LT|MT|-1}} more than the older ships. The ship had a [[metacentric height]] of {{convert|7.82|ft}} at deep load.{{sfn|Friedman 1985|p=440}}

The ship had four direct-drive Curtis [[steam turbine]] sets, each of which drove a propeller {{convert|12|ft|1.5|in|1}} in diameter.{{sfn|Stillwell|p=360}} They were powered by twelve [[Babcock & Wilcox]] [[water-tube boiler]]s.{{sfn|Friedman 1985|p=440}} The turbines were designed to produce a total of {{convert|34000|shp|lk=in}}, for a designed speed of {{convert|21|kn|lk=in}}.{{sfn|Breyer|p=214}} She was designed to normally carry {{convert|1548|LT|t|0}} of [[fuel oil]], but had a maximum capacity of {{convert|2305|LT|t|0}}. At full capacity, the ship could steam at a speed of {{convert|12|knots}} for an estimated {{convert|7552|nmi|-1|lk=in}} with a clean bottom. She had four {{convert|300|kW|0|adj=on}} [[turbo generator]]s.{{sfn|Friedman 1985|p=440}}

[[File:Forward_turrets_of_USS_Pennsylvania_during_fitting-out,_1916.jpeg|thumb|left|Fitting-out deck area around forward turrets in early weeks of 1916]]

''Pennsylvania'' carried twelve 45-[[caliber (artillery)#Barrel length|caliber]] [[14"/45 caliber gun|{{cvt|14|in|0}} guns]] in triple [[gun turret]]s.{{sfn|Friedman 1985|p=440}} The turrets were numbered from I to IV from front to rear. The guns could not elevate independently and were limited to a maximum elevation of +15° which gave them a maximum range of {{convert|21000|yd}}.{{sfn|Wright|pp=66, 123, 285}} The ship carried 100 shells for each gun. Defense against [[torpedo boat]]s was provided by twenty-two 51-caliber [[5"/51 caliber gun|{{cvt|5|in|0}} guns]] mounted in individual [[casemate]]s in the sides of the ship's hull. Positioned as they were they proved vulnerable to sea spray and could not be worked in heavy seas.{{sfn|Friedman 1985|pp=116, 440}} At an elevation of 15°, they had a maximum range of {{convert|14050|yd}}.{{sfn|Campbell|p=136}} Each gun was provided with 230 rounds of ammunition.{{sfn|Friedman 1985|p=440}} The ship mounted four 50-caliber [[3"/50 caliber gun|three-inch guns]] for [[Anti-aircraft warfare|anti-aircraft]] defense, although only two were fitted when completed. The other pair were added shortly afterward on top of Turret III.{{sfn|Stillwell|p=19}} ''Pennsylvania'' also mounted two {{convert|21|in|0|adj=on}} [[torpedo tube]]s submerged, one on each [[Broadside (naval)|broadside]], and carried 24 [[torpedo]]es for them.{{sfn|Friedman 1985|p=440}}{{sfn|Friedman 1986|p=117}}

The ''Pennsylvania''-class design continued the [[all or nothing (armor)|all-or-nothing]] principle of armoring only the most important areas of the ship begun in the ''Nevada'' class. The waterline [[Belt armor|armor belt]] of [[Krupp armor]] measured {{convert|13.5|in|mm|0}} thick and covered only the ship's machinery spaces and [[magazine (artillery)|magazines]]. It had a total height of {{convert|17|ft|6|in|1}}, of which {{convert|8|ft|9.75|in|1}} was below the waterline; beginning {{convert|2|ft|4|in|1}} below the waterline, the belt tapered to its minimum thickness of {{convert|8|in|0}}.{{sfn|Friedman 1985|p=440}} The transverse [[Bulkhead (partition)|bulkheads]] at each end of the ship ranged from 13 to 8&nbsp;inches in thickness. The faces of the gun turrets were {{convert|18|in|0}} thick while the sides were {{convert|9|-|10|in|0}} thick and the turret roofs were protected by {{convert|5|in|0}} of armor. The armor of the [[barbette]]s was {{convert|18|to|4.5|in|mm|0}} thick. The [[conning tower]] was protected by {{convert|16|in|0}} of armor and had a roof eight inches thick.{{sfn|Stillwell|p=359}}

The main armor deck was three plates thick with a total thickness of {{convert|3|in|0}}; over the steering gear the armor increased to {{convert|6.25|in|0}} in two plates. Beneath it was the splinter deck that ranged from {{convert|1.5|to|2|in|mm|0}} in thickness.{{sfn|Friedman 1985|pp=115, 118, 440}} The boiler uptakes were protected by a conical [[mantlet]] that ranged from {{convert|9|to|15|in}} in thickness.{{sfn|Stillwell|p=359}} A three-inch [[torpedo bulkhead]] was placed {{convert|9|ft|6|in|1}} inboard from the ship's side and the ship was provided with a complete [[double bottom]]. Testing in mid-1914 revealed that this system could withstand {{convert|300|lb}} of [[Trinitrotoluene|TNT]].{{sfn|Friedman 1985|pp=115, 118, 440}}

==Service history==
===Construction and World War I===
[[File:U.S.S. Pennsylvania.jpg|thumb|left|''Pennsylvania'' in her original configuration, December 1916]]
The [[keel]] for ''Pennsylvania'' was [[keel laying|laid down]] on 27 October 1913 at the [[Northrop Grumman Newport News|Newport News Shipbuilding]] and Dry Dock Company of [[Newport News, Virginia]]. Her completed [[hull (watercraft)|hull]] was [[ship launching|launched]] on 16 March 1915, thereafter beginning [[fitting-out]]. Work on the ship finished in mid-1916, and she was [[ship commissioning|commissioned]] on 12 June under the command of Captain [[Henry B. Wilson]]. The ship was assigned to the [[United States Fleet Forces Command|Atlantic Fleet]] and then completed final fitting out from 1 to 20 July. ''Pennsylvania'' then began [[sea trials]] in 20 July, steaming first to the southern drill grounds off the [[Virginia Capes]] and then north to the coast of [[New England]]. [[Rear Admiral]] [[Austin M. Knight]] and officers from the [[Naval War College]] came aboard on 21 August to observe fleet training exercises. Three days later, the ship was visited by [[Franklin Delano Roosevelt]], then the [[Assistant Secretary of the Navy]].{{sfn|DANFS Pennsylvania}}

Rear Admiral [[Henry T. Mayo]] transferred to ''Pennsylvania'' on 12 October, making her the [[flagship]] of the Atlantic Fleet. At the end of the year, she went into drydock at the [[New York Navy Yard]] for maintenance. After emerging from the shipyard in January 1917, she steamed south to join fleet exercises in the [[Caribbean Sea]], during which she stopped in: [[Culebra, Puerto Rico]]; [[Santo Domingo]], Dominican Republic; and [[Port-au-Prince]], Haiti. While in Port-au-Prince, ''Pennsylvania'' again hosted Roosevelt, who met with the [[President of Haiti]] aboard the ship. The battleship arrived back in [[Yorktown, Virginia]] on 6 April, the same day the [[United States declaration of war on Germany (1917)|United States declared war on Germany]], bringing the country into [[World War I]]. Since ''Pennsylvania'' was oil-fired, she did not join the ships of [[United States Battleship Division Nine (World War I)|Battleship Division Nine]], as the British had asked for coal-burning battleships to reinforce the [[Grand Fleet]]. As a result, she stayed in American waters and saw no action during the war.{{sfn|DANFS Pennsylvania}}

In August, ''Pennsylvania'' took part in a naval review for President [[Woodrow Wilson]]. Foreign naval officers visited the ship in September, including the Japanese [[Vice Admiral]] [[Isamu Takeshita]] and the Russian Vice Admiral [[Alexander Kolchak]]. For the rest of the year and into 1918, ''Pennsylvania'' was kept in a state of readiness through fleet exercises and gunnery training in [[Chesapeake Bay]] and [[Long Island Sound]]. She was preparing for night battle training on 11 November 1918, when the [[Armistice of 11 November 1918|Armistice with Germany]] came into effect, ending the fighting. She thereafter returned for another stint in the New York Navy Yard for maintenance that was completed on 21 November. She began the voyage to [[Brest, France]], on 2 December by way of [[Tompkinsville, Staten Island|Tomkinsville, New York]], in company with the transport ship {{USS|George Washington|ID-3018|2}} that carried Wilson to France to take part in the peace negotiations; they were escorted by ten [[destroyer]]s. The ships arrived on 13 December and the next day, ''Pennsylvania'' began the trip back to New York with Battleship Divisions Nine and Six. The battleships reached their destination on 26 December, where they took part in victory celebrations.{{sfn|DANFS Pennsylvania}}

=== Inter-war period ===
====1919–1924====
[[File:USS Pennsylvania NH 42741.jpg|thumb|left|''Pennsylvania'' underway, c. 1920]]
''Pennsylvania'' and the rest of the Atlantic Fleet departed on 19 February, bound for the Caribbean for another round of exercises in Cuban waters. The ship arrived back in New York on 14 April, and while there on 30 June, Mayo was replaced by Vice Admiral [[Henry Braid Wilson|Henry Wilson]]. On 8 July at Tomkinsville, a delegation consisting of: Vice President [[Thomas R. Marshall]]; [[Josephus Daniels]], the [[Secretary of the Navy]]; [[Carter Glass]], the [[United States Secretary of the Treasury|Secretary of the Treasury]]; [[William B. Wilson]], the [[United States Secretary of Labor|Secretary of Labor]]; [[Newton D. Baker]], the [[United States Secretary of War|Secretary of War]]; [[Franklin K. Lane]], the [[United States Secretary of the Interior|Secretary of the Interior]]; and Senator [[Champ Clark]] came aboard the ship for a cruise back to New York. The fleet conducted another set of maneuvers in the Caribbean from 7 January to April 1920, ''Pennsylvania'' returning to her berth in New York on 26 April. Training exercises in the area followed, and on 17 July she received the [[hull number]] BB-38.{{sfn|DANFS Pennsylvania}}

On 17 January 1921, ''Pennsylvania'' left New York, passed through the [[Panama Canal]] to [[Balboa, Panama]], where she joined the [[United States Pacific Fleet|Pacific Fleet]], which together with elements of the Atlantic Fleet was re-designated as the [[Battle Fleet]], with ''Pennsylvania'' as its flagship. On 21 January, the fleet left Balboa and steamed south to [[Callao, Peru]], where they arrived ten days later. The ships then steamed north back to Balboa on 2 February, arriving on 14 February. ''Pennsylvania'' crossed back through the canal to take part in maneuvers off Cuba and on 28 April she arrived in [[Hampton Roads]], Virginia, where President [[Warren G. Harding]], [[Edwin Denby (politician)|Edwin Denby]], the Secretary of the Navy, [[Theodore Roosevelt Jr.]], the Assistant Secretary of the Navy, and Admiral [[Robert Coontz]], the [[Chief of Naval Operations]] (CNO), came aboard the ship. Further training was held from 12 to 21 July in the Caribbean, after which she returned to New York. On 30 July, she proceeded on to [[Plymouth, Massachusetts]] for a visit that lasted until 2 August. Anothery drydock period in New York lasted from 5 to 20 August.{{sfn|DANFS Pennsylvania}}

''Pennsylvania'' departed New York thereafter, bound for the Pacific; she passed through the Panama Canal on 30 August and remained at Balboa for two weeks. On 15 September, she resumed the voyage and steamed north to [[San Pedro, Los Angeles]], which she reached on 26 September. The ship spent most of 1922 visiting ports along the US west coast, including [[San Francisco]], [[Seattle]], [[Port Angeles]], and [[San Diego]], and from 6 March to 19 April, she underwent a refit at the [[Puget Sound Navy Yard]]. She won the [[Battle Efficiency Award]] for the 1922 training year. She went back to Puget Sound on 18 December, and remained there into 1923. She left the shipyard on 28 January and steamed south to San Diego, where she stayed from 2 to 8 February, before continuing on to the Panama Canal. After passing through, she steamed to Culebra for a short visit. The ship then passed back through the canal and arrived back in San Pedro on 13 April. Beginning in May, she visited various ports in the area over the course of the rest of 1923, apart from a round of fleet training from 27 November to 7 December. She ended the year with another stint in Puget Sound from 22 December until 1 March 1924.{{sfn|DANFS Pennsylvania}}

====1924–1931====
[[File:USS Pennsylvania 1925 SLV Green.jpg|thumb|USS ''Pennsylvania'' during visit to Australia in 1925]]

The ship arrived in San Francisco on 3 March, where she loaded ammunition before joining the Battle Fleet in San Diego on 9 March. The fleet cruised south to the [[Gulf of Fonseca]], then continued south and passed through the Panama Canal to [[Bahía Limón]]. The ships visited several ports in the Caribbean, including in the [[US Virgin Islands]] and Puerto Rico before returning to the Pacific in early April. ''Pennsylvania'' arrived back in San Pedro on 22 April, where she remained until 25 June, when she steamed north to Seattle. By this time, she was serving as the flagship of Battle Division 3 of the Battle Fleet. While in the Seattle area, she took part in training exercises with the ships of her division that lasted until 1 September. Further training exercises took place from 12 to 22 September off San Francisco. She thereafter took part in joint training with the coastal defenses around San Francisco from 26 to 29 September. The ship underwent a pair of overhauls from 1 to 13 October and 13 December to 5 January 1925. ''Pennsylvania'' then steamed to Puget Sound on 21 January for a third overhaul that lasted from 25 January to 24 March.{{sfn|DANFS Pennsylvania}}

''Pennsylvania'' returned to San Pedro on 27 March and then joined the fleet in San Francisco on 5 April. The ships then steamed to Hawaii for training exercises before departing on 1 July for a major cruise across the Pacific to Australia. They reached [[Melbourne]] on 22 July, and on 6 August ''Pennsylvania'' steamed to [[Wellington]], New Zealand, where she stayed from 11 to 22 August. On the voyage back to the United States, they stopped in [[Pago Pago]] in [[American Samoa]] and Hawaii, before reaching San Pedro on 26 September. ''Pennsylvania'' went to San Diego for target practice from 5 to 8 October, thereafter returning to San Pedro, where she remained largely idle for the rest of 1925. She left San Pedro with the Battle Fleet on 1 February 1926 for another visit to Balboa, during which the ships conducted tactical training from 15 to 27 February. ''Pennsylvania'' spent early March in California before departing for Puget Sound on 15 March for another refit that lasted until 14 May, at which point she returned to San Pedro. Another tour of west coast ports began on 16 June and ended on 1 September back in San Pedro.{{sfn|DANFS Pennsylvania}}

[[File:USS Pennsylvania at 1927 naval review NARA 19-LC-19C.jpg|thumb|left|''Pennsylvania'' during a fleet review on 4 June 1927]]
''Pennsylvania'' remained at San Pedro from 11 December to 11 January 1927 when she left for another refit at Puget Sound that lasted until 12 March. She returned to San Francisco on 15 March and then moved to San Pedro the next day. She left to join training exercises off Cuba on 17 March; she passed through the canal between 29 and 31 March and arrived in [[Guantánamo Bay]] on 4 April. On 18 April, she left Cuba to visit [[Gonaïves]], Haiti before steaming to New York, arriving there on 29 April. After touring the east coast in May, she departed for the canal, which she crossed on 12 June. She remained in Balboa until 12 June, at which point she left for San Pedro, arriving on 28 June. The ship spent the rest of 1927 with training, maintenance, and a tour of the west coast. She went to Puget Sound for a refit on 1 April 1928 that lasted until 16 May, after which she went to San Francisco. She left that same day, however, and steamed back north to visit [[Victoria, British Columbia]]. She remained there from 24 to 28 May and then returned to San Francisco. She spent June visiting various ports, and in August she embarked [[Dwight F. Davis]], the Secretary of War, in San Francisco; she carried him to Hawaii, departing on 7 August and arriving on the 13th. ''Pennsylvania'' returned to Seattle on 26 August.{{sfn|DANFS Pennsylvania}}

Another cruise to Cuba took place in January 1929, after which she went to the [[Philadelphia Navy Yard]] on 1 June for a major refit and modernization. She received a number of modifications, including increased deck and turret roof armor, [[anti-torpedo bulge]]s, new turbo-generators, new turbines, and six new three-drum boilers. Her main battery turrets were modified to allow them to elevate to 30&nbsp;degrees, significantly increasing the range of her guns, and her secondary battery was revised. The number of 5-inch guns was reduced to twelve, and her 3-inch anti-aircraft guns were replaced with eight [[5"/25 caliber gun|5-inch /25 guns]]. Her torpedo tubes were removed, as were her [[lattice mast]]s, which were replaced with sturdier tripod masts. Her bridge was also enlarged to increase the space available for an admiral's staff, since she was used as a flagship. Her living space was increased to 2,037&nbsp;crew and marines, and she was fitted with two [[aircraft catapult|catapults]] for [[seaplane]]s.{{sfn|Breyer|p=214}}{{sfn|DANFS Pennsylvania}}

''Pennsylvania'' returned to service on 1 March 1931 and she conducted trials in [[Delaware Bay]] in March and April. She then steamed south to Cuba on 8 May for a training cruise before returning to Philadelphia on 26 May. Another cruise to Cuba followed on 30 July; the ship arrived there on 5 August and this time she steamed across the Caribbean to the Panama Canal, which she transited on 12 August to return to the Battle Fleet. She reached San Pedro on 27 August, where she remained for the rest of the year. She toured the west coast in January 1932 and before crossing over to [[Pearl Harbor]], where she arrived on 3 February. There, she took part in extensive fleet maneuvers as part of [[Fleet Problem XIII]]. She returned to San Pedro on 20 March, remaining there until 18 April, when she began another cruise along the coast of California. She returned to San Pedro on 14 November and remained there until the end of the year.{{sfn|DANFS Pennsylvania}}

====1932–1941====
[[File:USS Pennsylvania NH 67633.jpg|thumb|''Pennsylvania'' in [[Pearl Harbor]] in 1932, with tripod masts and her enlarged bridge]]

The ship departed San Pedro on 9 February to participate in [[Fleet Problem XIV]], which lasted from 10 to 17 February. She returned to San Francisco on 17 February and then went to San Pedro on 27 February, remaining there until 19 June. Another west coast cruise followed from 19 June to 14 November, and after returning to San Pedro, ''Pennsylvania'' stayed there inactive until early March 1934. From 4 to 8 March, she made a short visit to [[Hunters Point Naval Shipyard]] in San Francisco and then returned to San Pedro. From there, she went to join the fleet for [[Fleet Problem XV]], which was held in the Caribbean this year; she passed through the canal on 24 April, the maneuvers having already started on the 19th. They lasted until 12 May, at which point ''Pennsylvania'' went to Gonaïves with the rest of the fleet, which then continued on to New York, where it arrived on 31 March. There, ''Pennsylvania'' led the fleet in a naval review for now-President Franklin D. Roosevelt. On 15 June, Admiral [[Joseph M. Reeves]] took command of the fleet aboard ''Pennsylvania'', which was once again the fleet flagship.{{sfn|DANFS Pennsylvania}}

On 18 June, ''Pennsylvania'' left New York for the Pacific, stopping in Hampton Roads on 20 June on the way. She passed through the canal on 28 June and reached San Pedro on 7 July. She then went to Puget Sound for a refit that lasted from 14 July to 2 October. The ship left the shipyard on 16 October and returned to San Francisco two days later, beginning a period of cruises off the coast of California and visits to cities in the state. She ended the year in San Pedro, remaining there or in San Francisco until 29 April 1935, when she took part in [[Fleet Problem XVI]] in the Hawaiian islands. The maneuvers lasted until 10 June, and were the largest set of exercises conducted by the US Navy at the time. The ship then returned to San Pedro on 17 June and embarked on a cruise of the west coast for several months; on 16 December, she went to Puget Sound for another overhaul that lasted from 20 December to 21 March 1936. [[Fleet Problem XVII]] followed from 27 April to 7 June, this time being held off Balboa. She returned to San Pedro on 6 June and spent the rest of the year with training exercises off the west coast and Hawaii, ending the training program for the year in San Pedro on 18 November.{{sfn|DANFS Pennsylvania}}

The ship remained in port until 17 February, when she departed for [[San Clemente, California]] at the start of a tour along the west coast. She participated in [[Fleet Problem XVIII]], which lasted from 16 April to 28 May. Another stint in Puget Sound began on 6 June and concluded on 3 September, when she returned to San Pedro. She spent the rest of the year alternating between there and San Francisco, seeing little activity. She made a short trip to San Francisco in February 1938 and took part in [[Fleet Problem XIX]] from 9 March to 30 April. Another period in San Pedro followed until 20 June, after which she embarked on a two-month cruise along the west coast that concluded with another stay at Puget Sound on 28 September. After concluding her repairs on 16 December, she returned to San Pedro by way of San Francisco, arriving on 22 December. [[Fleet Problem XX]] occurred earlier the year than it had in previous iterations, taking place from 20 to 27 February 1939 in Cuban waters. During the exercises, Franklin Roosevelt and Admiral [[William D. Leahy]], the CNO, came aboard ''Pennsylvania'' to observe the maneuvers.{{sfn|DANFS Pennsylvania}}

The ship then went to Culebra on 27 February, departing on 4 March to visit Port-au-Prince, Haiti from 6 to 11 March. A stay in Guantanamo Bay followed from 12 to 31 March, after which she went to visit the [[US Naval Academy]] in Annapolis on 5 April. ''Pennsylvania'' began the voyage back to the Pacific on 18 April and passed through the canal at the end of the month, ultimately arriving back in San Pedro on 12 May. Another tour of the west coast followed, which included stops in San Francisco, [[Tacoma, Washington|Tacoma]], and Seattle, and ended in San Pedro on 20 October. She went to Hawaii to participate in [[Fleet Problem XXI]] on 2 April 1940. The exercises lasted until 17 May, after which the ship remained in Hawaii until 1 September, when she left for San Pedro. The battleship then went to Puget Sound on 12 September that lasted until 27 December;{{sfn|DANFS Pennsylvania}}  during the overhaul, she received another four 5-inch /25 guns.{{sfn|Breyer|p=214}} She returned to San Pedro on 31 December. [[Fleet Problem XXII]] was scheduled for January 1941, but the widening of [[World War II]] by this time led the naval command to cancel the exercises. On 7 January, ''Pennsylvania'' steamed to Hawaii as part of what was again the Pacific Fleet, based at Pearl Harbor. Over the course of the year, she operated out of Pearl Harbor and made a short voyage to the west coast of the United States from 12 September to 11 October.{{sfn|DANFS Pennsylvania}}

=== World War II ===
====Attack on Pearl Harbor====
[[File:USS Downes (DD-375), USS Cassin (DD-372) and USS Pennsylvania (BB-38) in Dry Dock No. 1 at the Pearl Harbor Naval Shipyard, 7 December 1941 (306533).jpg|thumb|upright=1.1|''Cassin'', ''Downes'' and ''Pennsylvania'' in the aftermath of the attack on Pearl Harbor]]
{{main|Attack on Pearl Harbor}}

On the morning of 7 December, ''Pennsylvania'' was in Dry Dock No. 1 in Pearl Harbor undergoing a refit; three of her four [[propeller|screws]] were removed. The destroyers {{USS|Cassin|DD-372|2}} and {{USS|Downes|DD-375|2}} were also in the dock with her. When it became clear that the port was under air attack from the Japanese fleet, ''Pennsylvania''{{'}}s crew rushed to their battle stations, and between 08:02 and 08:05, her anti-aircraft gunners began engaging the hostile aircraft. Japanese [[torpedo bomber]]s unsuccessfully attempted to torpedo the side of the drydock to flood it; having failed, several aircraft then [[strafe]]d ''Pennsylvania''. At 08:30, several high-altitude bombers began a series of attacks on the ship; over the course of the following fifteen minutes, five aircraft attempted to hit her from different directions. One of the Japanese bombers hit ''Downes'' and one scored a hit on ''Pennsylvania'' that passed through the boat deck and exploded in casemate No. 9. ''Pennsylvania''{{'}}s anti-aircraft gunners fired at all of these aircraft but failed to hit any of them, apparently owing to incorrect fuse settings that caused the shells to explode before they reached the correct altitude. The gunners did manage to shoot down a low-flying aircraft that attempted to strafe the ship; they claimed to have shot down another five aircraft, but the after-action investigation noted that only two aircraft were likely hit by ''Pennsylvania''{{'}}s guns.{{sfn|DANFS Pennsylvania}}

By 09:20, both destroyers were on fire from bomb hits and the fire had spread to ''Pennsylvania'', so the drydock was flooded to help contain the fire. Ten minutes later, the destroyers began to explode as the fires spread to ammunition magazines, and at 09:41, ''Downes'' was shattered by an explosion that scattered parts of the ship around the area. One of her torpedo tubes, weighing {{convert|500|to|1000|lb|kg}}, was launched into the air, striking ''Pennsylvania''{{'}}s [[forecastle]]. As part of her crew battled the fire in her bow, other men used the ship's boats to ferry anti-aircraft ammunition from stores in the West Loch of Pearl Harbor. Beginning at 14:00, the crew began preparatory work to repair the bomb damage; a 5-inch /25 gun and a 5-inch /51 casemate gun were taken from the damaged battleship {{USS|West Virginia|BB-48|2}} to replace weapons damaged aboard ''Pennsylvania''.{{sfn|DANFS Pennsylvania}} In the course of the attack, ''Pennsylvania'' had 15 men killed (including her executive officer), 14 missing, and 38 wounded.{{sfn|Smith|p=30}} On 12 December, ''Pennsylvania'' was refloated and taken out of the drydock; having been only lightly damaged in the attack, she was ready to go to sea. She departed Pearl Harbor on 20 December and arrived in San Francisco nine days later. She went into drydock at Hunter's Point on 1 January 1942 for repairs that were completed on 12 January.{{sfn|DANFS Pennsylvania}}

The ship left San Francisco on 20 February and began gunnery training before returning to San Francisco the next day. Further training followed in March, and from 14 April to 1 August, she took part in extensive maneuvers off the coast of California;{{sfn|DANFS Pennsylvania}} during this period, she underwent an overhaul at the [[Mare Island Naval Shipyard]] in San Francisco. The work involved considerably strengthening the ship's anti-aircraft capabilities, with ten [[Bofors 40 mm Automatic Gun L/60|Bofors 40 mm quad mounts]] and fifty-one [[Oerlikon 20 mm cannon#World War II|Oerlikon 20 mm]] single mounts. The tripod mainmast was removed, with the stump replaced by a deckhouse above which the aft main battery director cupola was housed. One of the new [[CXAM radar|CXAM-1]] radars was installed above the cupola. The older 5-inch /51 cal anti-ship guns in casemates and 5-inch /25 cal anti-aircraft guns were replaced with rapid fire [[5"/38 caliber gun|5-inch /38 cal]] guns in eight twin turret mounts. The new 5"/38 cal [[dual purpose gun|dual purpose]] guns could elevate to 85 degrees and fire at a rate of one round every four seconds.{{sfn|Breyer|p=214}} The ship briefly went to sea during the [[Battle of Midway]] as part of [[Task Force 1]], commanded by Vice Admiral [[William S. Pye]], but the ships did not see action during the operation.{{sfn|DANFS Pennsylvania}}

==== Aleutians and Makin Atoll ====
[[File:KiskaInvasionFleet.gif|thumb|left|The invasion fleet for [[Kiska]] in August 1943]]

On 1 August, ''Pennsylvania'' left San Francisco, bound for Pearl Harbor. She arrived there on 14 August and took part in further training, including guard tactics for [[aircraft carrier]] task forces. Another overhaul followed in San Francisco from 3 to 10 January 1943. After further training and tests at San Francisco and [[Long Beach]] that lasted into April, she departed to join the [[Aleutian Islands Campaign]] on 23 April. She bombarded [[Holtz Bay]] and [[Chichagof Harbor]] on 11–12 May to support the forces that went ashore on the island of [[Attu Island|Attu]]. While she was leaving the area on the 12th, the Japanese [[submarine]] {{ship|Japanese submarine|I-31||2}} launched a torpedo at the ship, which was observed by a patrolling [[PBY Catalina]] [[flying boat]]. The Catalina radioed ''Pennsylvania'', which took evasive maneuvers and escaped unharmed; a pair of destroyers then spent the next ten hours hunting the submarine before severely damaging her and forcing her to surface. ''I-31'' was later sunk by another destroyer the next day.{{sfn|DANFS Pennsylvania}}

''Pennsylvania'' returned to Holtz Bay on 14 May to conduct another bombardment in support of an infantry attack on the western side of the bay. She continued operations in the area until 19 May, when she steamed to [[Adak Island]] for another amphibious assault. While en route, one of her gasoline stowage compartments exploded, which caused structural damage, though no one was injured in the accident. She was forced to leave Adak on 21 May for repairs at Puget Sound that lasted from 31 May to 15 June; during the overhaul, another accidental explosion killed one man and injured a second. She left port on 1 August, bound for Adak, which she reached on 7 August. There, she became the flagship of Admiral [[Francis W. Rockwell (admiral)|Francis W. Rockwell]], commander of the task force that was to attack [[Kiska]]. The troops went ashore on 15 August but met no resistance, the Japanese having evacuated without US forces in the area having becoming aware of it. ''Pennsylvania'' patrolled off Kiska for several days before returning to Adak on 23 August.{{sfn|DANFS Pennsylvania}}

Two days later, the battleship departed Adak for Pearl Harbor, arriving there on 1 September. She embarked a contingent of 790&nbsp;passengers before steaming on 19 September, bound for San Francisco. She arrived there six days later and debarked her passengers before returning to Pearl Harbor on 6 October to take part in bombardment training from 20 to 23 October and 31 October – 4 November. Now the flagship of Rear Admiral [[Richmond K. Turner]], the commander of the Fifth Amphibious Force, itself part of the Northern Attack Force, ''Pennsylvania'' left Pearl Harbor on 10 November to lead the assault on [[Makin Atoll]], part of the [[Gilbert Islands]]. She was joined by three other battleships, four cruisers, three [[escort carrier]]s, and numerous transports and destroyers; they arrived off Makin on 20 November, and ''Pennsylvania'' opened fire on [[Butaritari Island]] that morning at a range of {{convert|14200|yd}}, beginning the [[Battle of Makin]]. Early on the morning of 24 November, the ship was rocked by an explosion off her starboard bow; lookouts reported that the escort carrier {{USS|Liscome Bay|CVE-56|2}} had been torpedoed and had exploded. Japanese torpedo bombers conducted repeated nighttime attacks on 25 and 26 November, but they failed to score any hits on the American fleet. ''Pennsylvania'' left the area on 30 November to return to Pearl Harbor.{{sfn|DANFS Pennsylvania}}

==== Marshalls and Marianas campaigns====
[[File:USS Pennsylvania bombarding Guam NH 67584.tiff|thumb|''Pennsylvania'' shelling Guam on 21 July]]

At the start of 1944, ''Pennsylvania'' was at Pearl Harbor; over the course of the first two weeks of January, she took part in maneuvers in preparation for landings on [[Kwajalein]] in the [[Marshall Islands]]. She departed Pearl Harbor on 22 January in company with the invasion fleet, and on 31 January she began her preparatory bombardment of the atoll to start the [[Battle of Kwajalein]]. Troops went ashore the next day, and ''Pennsylvania'' remained offshore to provide artillery support to the marines as they fought to secure the island. By the evening of 3 February, the Japanese defenders had been defeated, allowing the ship to depart to [[Majuro Atoll]] to replenish her ammunition supply. She left shortly thereafter, on 12 February, to support the next major attack on [[Eniwetok]] in the Marshalls; five days later she arrived off the island, the [[Battle of Eniwetok]] already underway, and over the course of 20 and 21 February, she shelled the island heavily to support the men fighting ashore. On 22 February, she supported the landing on [[Parry Island (Pacific)|Parry Island]], part of the Eniwetok atoll.{{sfn|DANFS Pennsylvania}}

On 1 March, ''Pennsylvania'' steamed back to Majuro before proceeding south to [[Havannah Harbor]] on [[Efate Island]] in the [[New Hebrides]]. She remained there until 24 April, when she left for a short visit to [[Sydney]], Australia from 29 April to 11 May, when she returned to Efate. She thereafter steamed to [[Purvis Bay|Port Purvis]] on [[Nggela Islands|Florida Island]], in the [[Solomon Islands|Solomons]], to participate in amphibious assault exercises. After replenishing ammunition and supplies at Efate, she left on 2 June, bound for [[Roi-Namur|Roi]], arriving there six days later. On 10 June, she joined a force of battleships, cruisers, escort carriers, and destroyers that had assembled for the [[Mariana and Palau Islands campaign|Marianas campaign]]. While en route that night, one of the escorting destroyers reported a [[sonar]] contact and the ships of the fleet took evasive maneuvers; in the darkness, ''Pennsylvania'' accidentally collided with the [[Troopship|troop transport]] {{USS|Talbot|DD-114|2}}. ''Pennsylvania'' incurred only minor damage and was able to continue with the fleet, but ''Talbot'' had to return to Eniwetok for emergency repairs.{{sfn|DANFS Pennsylvania}}

''Pennsylvania'' began her bombardment of [[Saipan]] on 14 June to prepare the island for the assault that came the next day. She continued shelling the island while cruising off [[Tinian]] on 15 June as the assault craft went ashore. On 16 June, she attacked Japanese positions at [[Orote Point]] on [[Guam]] before returning to Saipan. She left the area on 25 June to replenish at Eniwetok, returning to join the preparatory bombardment of Guam on 12 July. The shelling continued for two days, and late on 14 July, she steamed to Saipan to again replenish her ammunition. Back on station three days later, she continued to blast the island through 20 July. This work also included suppressing guns that fired on demolition parties that went ashore to destroy landing obstacles. On the morning of 21 July, ''Pennsylvania'' took up her bombardment position off Orote Point as the assault craft prepared to launch their attack. The ship operated off the island supporting the men fighting there for the next two weeks.{{sfn|DANFS Pennsylvania}}

==== Operations in the Philippines ====
[[File:USS Pennsylvania (BB-38) drydocked in an Advanced Base Sectional Dock at the Pacific c1944.jpg|thumb|''Pennsylvania'' drydocked in the Pacific, c. 1944]]

''Pennsylvania'' left Guam on 3 August to replenish at Eniwetok, arriving there on 19 August. From there, she steamed to [[Espiritu Santo]] in the New Hebrides before joining landing training off [[Guadalcanal]]. The ship left on 6 September as part of the Bombardment and Fire Support Group for the [[Battle of Peleliu|invasion of Peleliu]]. She bombarded the island from 12 to 14 September and supported the landings the next day. She shelled [[Anguar Island]] on 17 September and remained there for three days, departing on 20 September. She then steamed to [[Seeadler Harbor]] on [[Manus Island|Manus]], one of the [[Admiralty Islands]] for repairs. On 28 September, she arrived there and entered a floating dry dock on 1 October for a week's repairs. ''Pennsylvania'' left on 12 October in company with the battleships {{USS|Mississippi|BB-41|2}}, {{USS|Tennessee|BB-43|2}}, {{USS|California|BB-44|2}}, {{USS|Maryland|BB-46|2}}, and ''West Virginia'', under the command of Rear Admiral [[Jesse B. Oldendorf]]. These ships, designated [[Task Group 77.2]], formed the Fire Support Group for the upcoming [[Philippines campaign (1944–1945)|operations in the Philippines]]. They arrived off [[Leyte]] on 18 October and took up bombardment positions; over the next four days, they covered [[Underwater Demolition Team]]s, beach reconnaissance operations, and [[minesweeper]]s clearing the way for the landing force.{{sfn|DANFS Pennsylvania}}

On 24 October, reports of Japanese naval forces approaching the area led Oldendorf's ships to prepare for action at the exit of the [[Surigao Strait]].{{sfn|DANFS Pennsylvania}} Vice Admiral [[Shōji Nishimura]]'s Southern Force steamed through the Surigao Strait to attack the invasion fleet in [[Leyte Gulf]]; his force comprised Battleship Division 2—the battleships {{ship|Japanese battleship|Yamashiro||2}} and {{ship|Japanese battleship|Fusō||2}}, the [[heavy cruiser]] {{ship|Japanese cruiser|Mogami|1934|2}}, and four destroyers—and Vice Admiral [[Kiyohide Shima]]'s Second Striking Force—the heavy cruisers {{ship|Japanese cruiser|Nachi||2}} and {{ship|Japanese cruiser|Ashigara||2}}, the light cruiser {{ship|Japanese cruiser|Abukuma||2}}, and four more destroyers.{{sfn|Tully|pp=24–28}} As Nishimura's flotilla passed through the strait on the night of 24 October, they came under attack from American [[PT boat]]s, followed by destroyers, initiating the [[Battle of Surigao Strait]]. One of these destroyers torpedoed ''Fusō'' and disabled her, though Nishimura continued on toward his objective.{{sfn|Tully|p=152}}

In the early hours of 25 October, the Southern Force came into contact with Oldendorf's battleships, which had positioned themselves to [[Crossing the T|cross Nishimura's T]]. At 03:53, ''West Virginia'' opened fire, followed by some of the other battleships,{{sfn|DANFS Pennsylvania}} though ''Pennsylvania'' had trouble locating a target in the darkness with her search radar. Her older Mark 3 radar was not as effective as the more modern sets on ''West Virginia'' and some of the other battleships.{{sfn|Tully|p=196}} Task Group 77.2's battleships effectively annihilated Battleship Division 2; Shima's Second Striking Force had fallen behind and had not yet entered the fray. ''Yamashiro'' was set on fire and then exploded; she turned to flee, covered by a salvo of torpedoes from the burning ''Mogami'', but the American battleships were able to evade them without damage. Despite having disengaged from Oldendorf's battleships, ''Yamashiro'' was hit by more torpedoes and capsized and sank around 04:20.{{sfn|Tully|pp=208–210, 215–216}} Shima's ships passed the still-floating ''Fusō'' and realized that Nishimura had entered a trap, so he reversed course to flee; in the confusion, his flagship ''Nachi'' collided with ''Mogami'', damaging her and slowing her to be attacked by American light forces. She was later sunk, as were three of the four destroyers. Later on 25 October, ''Pennsylvania''{{'}}s anti-aircraft gunners helped to shoot down four aircraft that attacked a nearby destroyer.{{sfn|DANFS Pennsylvania}}{{sfn|Tully|pp=230–238, 259}}

[[File:USS Pennsylvania moving into Lingayen Gulf.jpg|thumb|left|''Pennsylvania'' leading {{USS|Colorado|BB-45|2}}, {{USS|Louisville|CA-28|2}}, {{USS|Portland|CA-33|2}} and {{USS|Columbia|CL-56|2}} into [[Lingayen Gulf]], Philippines, January 1945]]

Late on 28 October, ''Pennsylvania'' shot down a torpedo bomber. The ship remained on station off Leyte until 25 November, when she departed for Manus, from which she steamed to [[Kossol Roads]] off Palau on 15 December to refill her magazines. She conducted gunnery training on 22 December, and on 1 January 1945, ''Pennsylvania'' re-joined Oldendorf's Fire Support Group on the way to [[Lingayen Gulf]] for the next major operation in the Philippines. Over the course of 4–5 January, Japanese aircraft repeatedly attacked the ships, including [[kamikaze]]s that destroyed the escort carrier {{USS|Ommaney Bay|CVE-79|2}}. ''Pennsylvania'' began bombarding Japanese positions on [[Santiago Island (Philippines)|Santiago Island]] at the entrance to Lingayen Gulf on 6 January before entering the gulf that night to suppress Japanese guns while minesweepers cleared the area. The next morning, the rest of Oldendorf's ships joined her in the gulf to begin the main preparatory bombardment, which continued through the 8th. On 9 January, the amphibious assault began as troops from the [[Sixth United States Army]] went ashore.{{sfn|DANFS Pennsylvania}}

Japanese aircraft struck the invasion fleet on 10 January, and four bombs landed close to ''Pennsylvania'', though she was undamaged. Later that day, a fire control party directed ''Pennsylvania'' to shell a group of Japanese tanks that were massing to launch a counterattack on the beachhead. The ship patrolled outside the gulf from 10 to 17 January, when she returned to the gulf; she saw no further action, however, and she departed on 10 February for maintenance at Manus. From there, she left on 22 February for San Francisco, stopping in the Marshalls and at Pearl Harbor on the way. After arriving on 13 March, she underwent a thorough overhaul, including the replacement of her worn-out main battery and secondary guns.{{sfn|DANFS Pennsylvania}} She also received a new Mk.34 main battery director, which was equipped with the latest Mk.8 fire control radar, on her aft superstructure. With the kamikaze threat in mind, her anti-aircraft armament was increased to seventy-one 20&nbsp;mm guns in twenty-seven single and twenty-two twin mounts. An additional pair of 40&nbsp;mm Bofors guns in a twin mount was installed on top of turret 2, for a total of forty-two guns.{{sfn|McDonald|p=268}} With the work done, she went on sea trials off San Francisco, followed by training at San Diego. She left San Francisco on 12 July and arrived in Pearl Harbor on the 18th, where she engaged in further training from 20 to 23 July. The next day, she departed to join the invasion fleet off [[Okinawa Island|Okinawa]].{{sfn|DANFS Pennsylvania}}

While transiting the Pacific, she stopped to bombard [[Wake Island]] on 1 August. In the artillery duel with Japanese coastal guns, one of their shells detonated close enough that fragments disabled one of the ship's fire control directors for her 5-inch guns. One of her [[Curtiss SC Seahawk]]s was damaged in heavy seas, and the destroyer {{USS|Ordronaux||2}} recovered the pilot. ''Pennsylvania'' loaded ammunition at Saipan before continuing on to Okinawa, arriving there on 12 August where she became flagship of [[Task Force 95]]. That night, while moored next to ''Tennessee'' in [[Buckner Bay]], a Japanese torpedo bomber managed to penetrate the Allied defensive screen undetected; the aircraft launched its torpedo at ''Pennsylvania'' and hit her aft, causing serious damage. The torpedo opened a hole approximately {{convert|30|ft|m|abbr=on}} in diameter, causing the ship to take on a considerable amount of water and begin to settle by the stern. Damage control teams were able to contain the flooding. Twenty men were killed and another ten were injured in the attack, including Oldendorf, who was aboard at the time and suffered several broken ribs. ''Pennsylvania'' was the last major US warship to be damaged in the war. The next day, salvage [[tugboat|tugs]] towed her to shallow water where temporary repairs could be effected. On 15 August, the Japanese surrendered, ending the war.{{sfn|DANFS Pennsylvania}}{{sfn|Morison|p=118}}

=== Post-war career ===
[[File:USS Pennsylvania (BB-38) sinking off Kwajalein02 1948.jpg|thumb|right|''Pennsylvania'' sinking off Kwajalein Atoll, 10 February 1948]]

''Pennsylvania'' was taken under tow by a pair of tugboats on 18 August, bound for [[Apra Harbor, Guam]], where they arrived on 6 September. The next day, she was taken into a floating drydock, where a large steel patch was welded over the torpedo hole, which would allow the ship to make the voyage back for permanent repairs. The battleship {{USS|Missouri|BB-63|2}} relieved ''Pennsylvania'' as flagship on 15 September, and on 2 October, she was able to leave the drydock. Two days later, ''Pennsylvania'' steamed out of Guam, bound for Puget Sound, where repairs would be effected. She was escorted by the [[light cruiser]] {{USS|Atlanta|CL-104|2}} and the destroyer {{USS|Walke|DD-723|2}}. While still en route on 17 October, the ship's number 3 propeller shaft slipped aft. Divers were sent to cut the shaft loose; ''Pennsylvania'' now had just one operational screw, and the open propeller shaft was now allowing water to leak into the hull. She nevertheless completed the voyage to Puget Sound, arriving on 24 October. The ship received the [[Navy Unit Commendation]] for her wartime service there on 3 November.{{sfn|DANFS Pennsylvania}}

On 16 January 1946, ''Pennsylvania'' was designated to be expended as a [[target ship]] for the [[Operation Crossroads]] atomic bomb tests at [[Bikini Atoll]] to be carried out later that year. Repairs were completed enough to allow her to sail to the Marshall Islands, and she left Puget Sound on 24 February. After stopping in Pearl Harbor, she arrived in Bikini Atoll on 31 May, where she was anchored along with another eighty-three warships. The first explosion, Test Able, took place on 1 July, and was an air burst. After tests determined that the ship had not been contaminated with radiation, the crew returned to the ship from 3 to 24 July. The second blast, Test Baker, was done the next day. This was an underwater detonation, and ''Pennsylvania'' was moored just {{convert|1100|yd}} from [[ground zero]]. She was only lightly damaged from the blast, but the surge of water caused significant radioactive contamination; work parties came aboard the ship from 17 to 21 August to prepare the ship to be towed, and on the 21st she was taken under tow by the transport {{USS|Niagara|APA-87|2}}, which took her to Kwajalein, where she was decommissioned on 29 August. Various radiological and structural studies were completed over the next year and a half until she was scuttled off Kwajalein on 10 February 1948. She was officially stricken from the [[Naval Vessel Register]] on 19 February.{{sfn|DANFS Pennsylvania}}

The ship's bell is on display at The [[Pennsylvania State University]] near the main entrance of the Wagner Building, home of the university's [[ROTC]] programs. It has been on permanent loan to the university from the [[United States Department of the Navy|Department of the Navy]] since 1955.{{sfn|Penn State}} Two of the ship's 14-inch guns that had been replaced during the 1945 overhaul are on outdoor display at the [[Pennsylvania Military Museum]] in [[Boalsburg, Pennsylvania]].{{sfn|USS Pennsylvania}}

== Footnotes ==

{{reflist|20em}}

== References ==
* {{cite web
  |url=https://www.psu.edu/ur/about/markers/others/bell.html
  |title=Bell of the Battleship U.S.S. Pennsylvania
  |work=[[Penn State Historical Markers]]
  |publisher=[[Pennsylvania State University]]
  |date=6 December 2016
  |access-date=15 October 2019
  |ref={{SfnRef|Penn State}}
  }}
* {{cite book
  | last = Breyer
  | first = Siegfried
  | year = 1974
  | title = Battleships and Battle Cruisers 1905–1970
  | publisher = Doubleday
  | location = Garden City
  | oclc = 613091012
  | ref = {{SfnRef|Breyer}}
  }}
* {{cite book
  |last=Campbell
  |first=John
  |title=Naval Weapons of World War II
  |year=1985
  |publisher=Naval Institute Press
  |location=Annapolis
  |isbn= 0-87021-459-4
  |ref={{SfnRef|Campbell}}
  }}
* {{cite web
  |url=https://www.history.navy.mil/research/histories/ship-histories/danfs/p/pennsylvania-ii.html
  |title=Pennsylvania III (Battleship No. 38)
  |work=[[Dictionary of American Naval Fighting Ships]]
  |publisher=[[Naval History & Heritage Command]]
  |date=6 December 2016
  |access-date=7 January 2019
  |ref={{SfnRef|DANFS Pennsylvania}}
  }}
* {{cite book
  |last=Friedman
  |first=Norman
  |title=U.S. Battleships: An Illustrated Design History
  |publisher= Naval Institute Press
  |location=Annapolis
  |year=1985
  |isbn= 978-0-87021-715-9
  |ref={{SfnRef|Friedman 1985}}
  }}
* {{cite book
  |last=Friedman
  |first=Norman
  |chapter=United States of America
  |pages=105–133
  |editor1-last=Gardiner
  |editor1-first=Robert
  |editor2-last=Gray
  |editor2-first=Randal
  |title=Conway's All the World's Fighting Ships 1906–1921
  |year=1986
  |location=London
  |publisher=Conway Maritime Press
  |isbn=978-0-85177-245-5
  |ref={{sfnRef|Friedman 1986}}
  | url=https://archive.org/details/conwaysallworlds0000unse_z3o0
  |name-list-style=amp
  }}
* {{cite book
  |last=McDonald
  |first=Rod
  |title=Pearl Harbor's Revenge: How the Devastated US Battleships Returned to War
  |publisher=Frontline Books
  |location=Philadelphia
  |year=2023
  |isbn=978-1-39901-329-1
  |ref={{sfnRef|McDonald}}
  }}
* {{cite book
  | last = Morison
  | first = Samuel Eliot
  | title = History of United States Naval Operations in World War II
  | volume = XII
  | publisher = Castle
  | location = Edison
  | year = 2001
  | orig-year = 1958
  | isbn = 978-0-7858-1313-2
  | ref = {{SfnRef|Morison}}
  }}
* {{cite book
  | last = Smith
  | first = Myron J. Jr.
  | year = 1983
  | title = Keystone Battlewagon U.S.S. Pennsylvania (BB-38)
  | publisher = Pictorial Histories Publishing Company, Inc.
  | location = Charleston
  | isbn = 0-933126-27-1
  | ref = {{SfnRef|Smith}}
  }}
* {{cite book
  |last=Stillwell
  |first=Paul
  |title=Battleship Arizona: An Illustrated History
  |publisher= Naval Institute Press
  |location=Annapolis
  |year=1991
  |isbn=0-87021-023-8
  | ref = {{SfnRef|Stillwell}}
  }}
* {{cite book
  |last=Tully
  |first=Anthony P.
  |title=Battle of Surigao Strait
  |publisher=Indiana University Press
  |location=Bloomington
  |year=2009
  |isbn=978-0-253-35242-2
  |ref={{SfnRef|Tully}}
  }}
* {{cite journal
  | editor-last = Wright
  | editor-first = Christopher C
  |date=Mar 2002
  | title = The US Navy's Study of the Loss of the Battleship Arizona
  |journal = Warship International
  | publisher = International Naval Research Organization
  | location = Toledo
  | volume = XXXIX–XL
  | issue = 3–4, 1
  | pages = 44–105, 247–99, 360–80
  | issn = 0043-0374
  |ref={{SfnRef|Wright}}
  }}
* {{cite web
  |url=https://www.pamilmuseum.org/uss-pennsylvania/
  |website=pamilmuseum.org
  |title=USS Pennsylvania
  |publisher=Pennsylvania Military Museum
  |access-date=15 October 2019
  |ref={{SfnRef|USS Pennsylvania}}
  |archive-date=15 October 2019
  |archive-url=https://web.archive.org/web/20191015193430/https://www.pamilmuseum.org/uss-pennsylvania/
  |url-status=dead
  }}

==Further reading==
*{{cite journal|last1=Allen |first1=Keith|title=Question 14/50: Pennsylvania (BB-38) at the Battle of Surigao Strait|journal=Warship International |date=2015 |volume=LII |issue=2 |pages=124–126 |issn=0043-0374}}

== External links ==

* {{Commons category-inline|USS Pennsylvania (BB-38)}}
* {{navsource|01/38a}}
*{{cite web|url=https://www.pacificwrecks.com/ships/hms/prince_of_wales/death-of-a-battleship-2012-update.pdf|title=Death of a Battleship: A Re-Analysis of the Tragic Loss of HMS Prince of Wales, A Marine Forensics Analysis of the Sinking|last1=Garzke|first1=William H.|last2=Dulin|first2=Robert O.|last3=Denlay|first3=Kevin V.|publisher=Society of Naval Architects and Marine Engineers}}

{{Pennsylvania class battleship}}
{{1948 shipwrecks}}
{{Authority control}}

{{DEFAULTSORT:Pennsylvania (BB-38)}}
[[Category:Pennsylvania-class battleships]]
[[Category:Ships built in Newport News, Virginia]]
[[Category:1915 ships]]
[[Category:World War I battleships of the United States]]
[[Category:World War II battleships of the United States]]
[[Category:Ships present during the attack on Pearl Harbor]]
[[Category:Ships of the Aleutian Islands campaign]]
[[Category:Ships involved in Operation Crossroads]]
[[Category:Ships sunk as targets]]
[[Category:Maritime incidents in 1946]]
[[Category:Maritime incidents in 1948]]