Baltimore-class cruiser

The Baltimore-class cruiser was the standard American heavy cruiser of the Second World War, a large, fast, and heavily armed ship with nine 8-inch guns in three triple turrets, a powerful anti-aircraft battery, and a speed of 33 knots. Fourteen ships were built between 1941 and 1945, and they served in the Pacific, where they screened carriers, bombarded Japanese-held islands, and fought in the battles of the Philippine Sea, Leyte Gulf, Iwo Jima, and Okinawa. The class remained in service after the war, fighting in Korea and Vietnam, and serving as the basis for the later Oregon City and Des Moines classes. The Baltimore class was one of the most successful cruiser designs of the Second World War.

1. Key Facts

Field	Value
Type	Heavy cruiser
Country	United States
Designer	US Navy Bureau of Construction and Repair
Production	1941–1945
Number built	14 (17 ordered; 3 completed as Oregon City class)
Displacement	14,472 tons standard; about 17,031 tons full load
Length	205.3 metres (673 ft 5 in)
Beam	21.6 metres (70 ft 10 in)
Draught	7.3 metres (24 ft)
Propulsion	Steam turbines, 120,000 shaft horsepower, 4 shafts
Speed	33 knots
Range	About 10,000 nautical miles at 15 knots
Complement	About 1,142 officers and men (wartime up to 1,700)
Main armament	9 × 8-inch (203 mm) guns in 3 triple turrets
Secondary armament	12 × 5-inch (127 mm) guns in 6 twin turrets
Anti-aircraft armament	48 × 40 mm Bofors; 24 × 20 mm Oerlikon
Aircraft	4 × floatplanes, 2 catapults
Armour	Belt 4–6 inches; deck 2.5 inches; turrets 6–8 inches
Main theatres	Pacific 1943–1945; Korea 1950–1953; Vietnam 1960s

2. Origins and Development

The Need for a New Heavy Cruiser

The Baltimore class was developed in the late 1930s, when the United States Navy needed a new heavy cruiser to replace the older Northampton and Portland classes, and to match the heavy cruisers being built by Japan and Germany. The Washington Naval Treaty, which had limited cruiser size to 10,000 tons and guns to 8 inches, expired in 1936, and the Navy was free to build a larger, more heavily protected cruiser. The Baltimore class was the result, a ship of 14,472 tons standard displacement, with a thicker armour belt, a more powerful machinery plant, and a heavier anti-aircraft battery than any earlier American cruiser. The class was designed to operate with the fast carrier task forces, and to protect them against air attack and against Japanese surface ships.

Design and the Treaty Limits

The Baltimore class was designed to the limits of what the Navy could build in the time available, with a hull that was longer and wider than that of the earlier cruisers, and with a machinery plant that produced 120,000 shaft horsepower, twice that of the earlier classes. The ship was armed with nine 8-inch guns in three triple turrets, twelve 5-inch guns in six twin turrets, and a powerful anti-aircraft battery of Bofors and Oerlikon guns. The armour was thicker than that of the earlier cruisers, with a belt of 4 to 6 inches and a deck of 2.5 inches, which gave the ship good protection against 8-inch shells and against bombs. The Baltimore class was a balanced design, with good speed, good protection, and good firepower, and it became the standard American heavy cruiser of the war.

Construction Programme

Fourteen Baltimore-class cruisers were built between 1941 and 1945, by the Fore River Shipyard in Quincy, Massachusetts, and the New York Shipbuilding Corporation in Camden, New Jersey. The first ship, USS Baltimore, was launched in July 1942 and commissioned in April 1943, and the last ships were completed in 1945, too late to see combat in the Second World War. The class was built quickly, because the United States needed cruisers to escort carriers in the Pacific, and the shipyards were able to build a Baltimore in about two years, using mass-production methods. The Baltimore class was one of the largest cruiser programmes of the war, and it showed the industrial power of the United States.

The Oregon City and Des Moines Classes

The Baltimore class was the basis for two later classes, the Oregon City class, which was a Baltimore with a more compact superstructure, and the Des Moines class, which was a larger, more heavily armed version with automatic 8-inch guns. Three ships ordered as Baltimores were completed as Oregon City-class cruisers, and the Des Moines class, built after the war, used the Baltimore hull as its starting point. The Baltimore class was the parent of a family of cruisers that served the United States Navy for more than thirty years, and it showed how a successful design could be improved and adapted for new roles.

3. Technical Design

Hull, Machinery, and Speed

The Baltimore class was 205.3 metres long, 21.6 metres wide, and displaced 14,472 tons standard and about 17,031 tons at full load. Her steam turbines produced 120,000 shaft horsepower, driving four shafts, and gave her a top speed of 33 knots, which made her fast enough to operate with the carrier task forces. Her range was about 10,000 nautical miles at 15 knots, which was enough for operations in the Pacific, and her crew of about 1,142 officers and men, rising to 1,700 in wartime, was well trained and experienced. Her hull was strong and well built, and it could survive damage that would have sunk a smaller ship, as the class proved in the Pacific, where several ships were hit by kamikaze aircraft and survived.

Main Battery and Fire Control

The main battery of the Baltimore class was nine 8-inch/55 guns in three triple turrets, two forward and one aft, controlled by a Mk 34 fire-control system with a Mk 8 radar, which allowed the ship to engage surface targets at long range and in bad weather. The 8-inch gun could fire a 118-kilogram shell to a range of about 27 kilometres, and it could fire three to four rounds per minute, which gave the Baltimore class a powerful broadside. The fire-control system was one of the best in the world, and it allowed the Baltimore class to bombard Japanese-held islands with great accuracy, and to engage Japanese surface ships at long range. The main battery was the heart of the ship, and it was the reason why the Baltimore class was so effective in the Pacific.

Secondary and Anti-Aircraft Armament

The secondary armament of the Baltimore class was twelve 5-inch/38 guns in six twin turrets, which could fire at aircraft and at surface targets, and which gave the ship a powerful anti-aircraft battery. The anti-aircraft armament also included forty-eight 40-millimetre Bofors guns and twenty-four 20-millimetre Oerlikon cannon, which gave the ship a strong defence against Japanese aircraft, including the kamikaze. The Bofors gun was the best light anti-aircraft gun of the war, and the Baltimore class carried more of them than any earlier American cruiser. The ship also carried four floatplanes, launched from two catapults, which were used for reconnaissance and for spotting the fall of shot, though they were rarely used in combat after 1944, when radar had made them less necessary.

4. Service in the Pacific

The Philippine Sea and Leyte Gulf

The Baltimore class first saw combat in the Pacific in 1943, where its ships screened the carriers and bombarded Japanese-held islands, and where they fought in the Battle of the Philippine Sea in June 1944, the great carrier battle in which the Japanese naval air arm was destroyed. The Baltimore-class cruisers were part of the screen for the American carriers, and they shot down many Japanese aircraft, and they helped to protect the carriers against air attack. At Leyte Gulf in October 1944, the largest naval battle in history, the Baltimore-class cruisers screened the carriers and the invasion fleet, and they fought off Japanese aircraft and submarines, and they bombarded the beaches before the landings. The class performed well in its first combat, and it established a reputation for reliability and for fighting spirit.

Iwo Jima and Okinawa

At Iwo Jima in February 1945, the Baltimore-class cruisers bombarded the island before the landings, providing fire support for the Marines, and they screened the carriers against Japanese air attack. At Okinawa in April 1945, the class was in the thick of the fighting, screening the carriers and bombarding the island, and serving as a defence against kamikaze aircraft. Several Baltimore-class cruisers were hit by kamikaze aircraft at Okinawa, but they survived, thanks to their thick armour and their good damage control. The Okinawa campaign was the hardest test of the class, and it showed that the Baltimore cruisers were tough, well built, and well fought. The class earned many battle stars for its service in the Pacific, and its ships were decorated for their service.

Bombardment and Carrier Screening

The main roles of the Baltimore class in the Pacific were bombardment and carrier screening, because its 8-inch guns were effective against shore targets, and its anti-aircraft battery was effective against Japanese aircraft. The class bombarded Japanese-held islands from Tarawa to Okinawa, softening up the defences before the landings, and it screened the carriers, protecting them against air attack and against Japanese submarines. The Baltimore class was a versatile ship, and it could do both jobs well, which was why it was used in every major operation in the Pacific from 1943 to 1945. Its service in the Pacific was the most important of its career, and it showed that the heavy cruiser, properly used, was still a valuable ship in the age of the aircraft carrier.

5. Service in Korea and Vietnam

The Korean War

After the Second World War, the Baltimore class remained in service with the United States Navy, and it fought in the Korean War from 1950 to 1953, where its ships bombarded North Korean positions, screened carriers, and patrolled the coast. The class was well suited to the Korean War, because its 8-inch guns were effective against shore targets, and its speed and its anti-aircraft armament made it useful for escorting carriers. The Baltimore-class cruisers served in Korea for the whole of the war, and they earned battle stars for their service. After Korea, the class was modernised, with improved anti-aircraft guns and electronics, and it continued to serve into the 1960s and 1970s.

Vietnam and the Cold War

In the 1960s, the Baltimore class served in Vietnam, where its ships bombarded Viet Cong positions, patrolled the coast, and provided fire support for American and South Vietnamese troops. The class was also used for showing the flag in the Mediterranean and the Far East, and for training, and it remained in service until the 1970s, when it was gradually retired as newer cruisers entered service. The Baltimore class was one of the longest-serving cruiser designs of the Second World War, and it served with distinction in three wars. Its last ships were decommissioned in the 1970s, ending a career of more than thirty years.

6. Strengths

Firepower, Protection, and Speed

The greatest strengths of the Baltimore class were its firepower, its protection, and its speed, because nine 8-inch guns gave it a powerful broadside, its armour belt of 4 to 6 inches gave it good protection against 8-inch shells and against bombs, and its speed of 33 knots made it fast enough to operate with the carrier task forces. The class was a balanced design, with no major weakness, and it could screen carriers, bombard shore targets, and fight surface ships, and it did all of these jobs well. Its anti-aircraft battery was also strong, with Bofors and Oerlikon guns that gave it a good defence against Japanese aircraft. The Baltimore class was a cruiser that could do everything, and it was trusted by the admirals who commanded it.

Versatility and Reliability

The Baltimore class was versatile and reliable, because it was well built, with a strong hull and a good machinery plant, and because its crew was well trained and experienced. The class served in the Pacific, in Korea, and in Vietnam, and it performed well in each war, which showed that it was a design that could be adapted for new roles. Its reliability was also a strength, because it could operate for long periods at sea without breaking down, and it could survive damage that would have sunk a smaller ship. The Baltimore class was a cruiser that the Navy could depend on, and it was one of the most successful cruiser designs of the Second World War.

7. Weaknesses

Size, Cost, and Crew

The main weakness of the Baltimore class was its size and its cost, because it was a large, expensive ship, with a crew of more than 1,100 men, and it required a great deal of fuel, ammunition, and maintenance. The class was also vulnerable to air attack, because its anti-aircraft guns, though powerful, could not stop every kamikaze, and several ships were hit at Okinawa. The Baltimore class was also too large for some roles, such as patrol and escort, where a smaller, cheaper ship would have been more economical. These were minor weaknesses compared with its strengths, but they were real, and they were among the reasons why the class was gradually retired in the 1970s, as newer, more specialised ships entered service.

The Limits of the Heavy Cruiser

The Baltimore class was the last of the gun heavy cruisers, because the age of the missile had arrived, and the heavy cruiser, with its 8-inch guns, was no longer the most effective ship for the Navy’s needs. The class was modernised after the war, with new anti-aircraft guns and electronics, but it could not be adapted to carry missiles without a major rebuild, and it was eventually replaced by missile cruisers and destroyers. The Baltimore class was a superb gun cruiser, but it was a product of its time, and its time had passed by the 1970s. Its retirement was the end of an era, the era of the big-gun cruiser that had begun in the 1920s.

8. Notable Ships

USS Baltimore and USS Canberra

USS Baltimore, CA-68, was the lead ship of the class, commissioned in April 1943, and she served in the Pacific, earning nine battle stars, and she carried President Franklin D. Roosevelt to the Yalta Conference in 1945. USS Canberra, CA-70, was named for the Australian cruiser HMAS Canberra, sunk at Savo Island in 1942, and she served in the Pacific, where she was torpedoed by a Japanese aircraft in October 1944 and survived, and she later served in Vietnam. USS Quincy, CA-71, was named for the American cruiser sunk at Savo Island, and she served in Normandy, where she bombarded the beaches on D-Day, and in the Pacific, where she served at Okinawa. These ships were among the most distinguished of the class, and they are remembered for their service in three wars.

USS Pittsburgh and the Typhoon

USS Pittsburgh, CA-72, was famous for surviving a typhoon in June 1945, in which her bow was torn off by the heavy seas, yet she remained afloat and was towed to Guam for repairs. The incident showed the toughness of the Baltimore class, and it became a legend in the Navy. USS Saint Paul, CA-73, served in the Pacific, in Korea, and in Vietnam, and she was the last Baltimore-class cruiser in service, decommissioned in 1971. The class served with distinction in every theatre, and its ships earned many battle stars and decorations. The Baltimore class was a class of which the United States Navy was proud, and its ships are remembered for their service in three wars.

9. Legacy

The Last Gun Cruisers

The legacy of the Baltimore class is that it was the last of the great gun cruisers, a class that served the United States Navy for more than thirty years, in three wars, and that set the standard for the heavy cruiser. The class was the basis for the Oregon City and Des Moines classes, and it influenced the design of later American cruisers, including the missile cruisers that replaced it. The Baltimore class showed that a well-designed cruiser, with good speed, good protection, and good firepower, could remain useful for decades, and that it could be adapted for new roles. Its long service was a tribute to its designers and to its crews.

Preservation and Memory

Several Baltimore-class cruisers were preserved as museum ships, though most were scrapped in the 1970s, and their memory is kept alive by veterans’ associations and by museums. USS Salem, CA-139, a Des Moines-class cruiser based on the Baltimore design, is preserved as a museum ship in Quincy, Massachusetts, and she is the closest surviving example of the Baltimore family. The Baltimore class is remembered as one of the best cruiser designs of the Second World War, and as a ship that served its country in three wars and many oceans around the world.

Frequently Asked Questions

What is the Baltimore-class cruiser?
It is an American heavy cruiser class of the Second World War, with nine 8-inch guns in three triple turrets, twelve 5-inch guns, and a speed of 33 knots.

How many Baltimore-class cruisers were built?
Fourteen were built between 1941 and 1945, by the Fore River Shipyard and the New York Shipbuilding Corporation.

Where did the class serve in the Second World War?
It served in the Pacific, at the Philippine Sea, Leyte Gulf, Iwo Jima, and Okinawa, screening carriers and bombarding Japanese-held islands.

What was the main armament?
Nine 8-inch/55 guns in three triple turrets, plus twelve 5-inch/38 guns and a powerful anti-aircraft battery of Bofors and Oerlikon guns.

Did the class serve after the war?
Yes. It served in Korea and Vietnam, and its last ships were decommissioned in the 1970s.

Which ship carried President Roosevelt to Yalta?
USS Baltimore, CA-68, the lead ship of the class, carried President Franklin D. Roosevelt to the Yalta Conference in 1945.

Sources

• The Naval History and Heritage Command, Baltimore-class cruiser records
• Norman Friedman, US Cruisers: An Illustrated Design History
• The National WWII Museum, cruiser exhibits
• Robert Gardiner, Conway’s All the World’s Fighting Ships 1922–1946
• The US Navy, Dictionary of American Naval Fighting Ships
• The USS Salem Museum, Quincy, Massachusetts, cruiser collection