Fleet problem

The Fleet Problems are a series of naval exercises of the United States Navy conducted in the interwar period and since the 2010s. 
The first 21 were conducted between 1923 and 1940. They are labeled with Roman numerals, from Fleet Problem I through Fleet Problem XXI. A 22nd Fleet Problem exercise, scheduled for 1941, was canceled because of World War II. After this, Fleet Problems underwent a prolonged hiatus, with other names being used to describe such naval exercise. However, the term was revived in 2015 or 2016 under Admiral Scott H. Swift, and Fleet Problem XXIII was held by the Pacific Fleet, with Fleet Problems XXIV through XXVIII occurring over the following years.
The fleet problems were usually once-a-year exercises in which U.S. naval forces would engage in mock battles. One or more of the forces would play the part of a European or Asian navy. They were the culmination of the Navy's annual training maneuvers.
Interwar Fleet Problems.
Fleet Problem I.
Fleet Problem I was held in February and March 1923 and was staged off the coast of Panama. The attacking Black force, using battleships to represent aircraft carriers, tested the defenses of the Panama Canal. A single plane launched from —representing a carrier air group—dropped 10 miniature bombs and theoretically "destroyed" the spillway of the Gatun Dam.
Fleet Problems II, III, IV.
Fleet Problems II, III, and IV were held concurrently in January and February 1924 took place in the Caribbean and simulated actions that might occur in the Pacific.
Fleet Problem II.
Fleet Problem II simulated the first leg of a westward advance across the Pacific.
Fleet Problem III.
This exercise focused on a defense of the Panama Canal from the Caribbean side. The Blue force was defending the canal from an attack from the Caribbean by the Black force, operating from an advance base in the Azores. It was to practice amphibious landing techniques and the rapidity of transiting a fleet through the canal from the Pacific side.
In the exercise, a Black force special operations action resulted in the "sinking" of Blue force battleship in the Culebra Cut which would have blocked the canal.
Fleet Problem IV.
This problem simulated the movement from a main base in the western Pacific to the Japanese home islands—represented in that case by islands, cities, and countries surrounding the Caribbean.
Fleet Problem V.
Fleet Problem V was held in March and April 1925 and simulated an attack on Hawaii. The Black force, the aggressor, was given the United States' first aircraft carrier, along with two seaplane tenders and other ships outfitted with aircraft, while the defending Blue force had no carriers. In addition, aircraft aboard the battleship could not be launched for lack of a working catapult. "Langley"s positive performance helped speed the completion of aircraft carriers and .
One aspect of Fleet Problem V was conducted near Guadalupe Island off Baja California and involved attacking a lightly held position and refueling at sea.
Fleet Problem VI.
Held off the west coast of Central America in early 1926.
Fleet Problem VII.
This fleet problem was held March 1927 and involved defense of the Panama Canal. The highlight of the exercise was ’s successful air raid on the Panama Canal.
Fleet Problem VIII.
Held in April 1928 between California and Hawaii and pitted Orange, a cruiser force from Pearl Harbor, versus Blue, the Battle Force. It also involved a convoy search and anti-submarine operations.
Fleet Problem IX.
This scenario in January 1929 studied the effects of an attack upon the Panama Canal and conducted the operations necessary to carry out such an eventuality, and pitted the Battle Fleet (less submarines and "Lexington") against a combination of forces including the Scouting Force (augmented by "Lexington"), the Control Forces, Train Squadron 1, and 15th Naval District and local army defense forces. These forces represented a significant commitment of the total US Navy: 72% of the fleet's battleships, 68% of the destroyers, and 52% of modern combat aircraft were involved in the scenario. In a daring move, "Saratoga" was detached from the fleet with only a single cruiser as escort to make a wide sweep to the south and "attack" the Panama Canal, which was defended by the Scouting Fleet and "Saratoga"s sister ship, "Lexington". She successfully launched her strike on 26 January and, despite being "sunk" three times later in the day, proved the versatility of a carrier-based fast task force.
Fleet Problem X.
Held in 1930 in Caribbean waters. This time, however, "Saratoga" and "Langley" were "disabled" by a surprise attack from "Lexington", showing how quickly air power could swing the balance in a naval action.
Fleet Problem XI.
Held in April 1930 in the Caribbean.
Fleet Problem XII.
Held in 1931 in waters west of Central America and Panama.
Black, attacking from the west, was to land forces and establish bases in Central America and destroy the Panama Canal, while Blue defended with an aviation-heavy fleet.
Blue's two carrier groups, centered on "Saratoga" and "Lexington", attacked the invasion fleets but failed to stop the landings and got too close to the Black fleets.
Fleet Problem XIII.
Fleet Problem XIII began in March 1932, one month after Army/Navy Grand Joint Exercise 4. Blue, based in Hawaii, was to sail east and invade three "enemy" ports on the North American Pacific coastline to try and gain a foothold for future operations. Blue had nine battleships, one aircraft carrier, and many lesser ships. Black defended with one modern aircraft carrier and some fictional battleships, as well as a number of actual cruisers, submarines, and many other ships.
Blue's advance was quickly located by Black's picket line of submarines which then took heavy losses from air attack. Both sides put a priority on destroying the enemy aircraft carrier, launching air attacks almost simultaneously after a few days of probing. Significant damage was laid on both carriers, with Blue's carrier eventually "sunk" by torpedo from a Black destroyer.
After-action critiques stressed the growing importance of naval aviation, and an increased need for the construction of aircraft carriers in the event of a war in the Pacific. Submarines operating at or near the surface were seen to be critically vulnerable to air observation and attack. The exercise showed that one carrier was insufficient for either fleet attack or area defense, so the practice of two or more carriers operating together became policy. Admiral Harry E. Yarnell said that six to eight carriers would be required for a Pacific campaign, but no orders were placed for new carriers, as Depression-era financial difficulties caused President Herbert Hoover to limit naval expenses.
Fleet Problem XIV.
Held 10–17 February 1933, Fleet Problem XIV was the first naval exercise to test simulated aircraft carrier attacks against the west coast of the United States. Pacific cities had for decades vied for permanent stationing of U.S. military assets, and vulnerabilities exposed through the exercises were used by metropolitan navy boosters to leverage their cases. In spite of early Navy plans for San Francisco to be home port for the main west coast fleet, these plans had failed to materialize with San Diego incrementally gaining the majority of navy investments.
Fleet Problem XIV occurred the month before Franklin D. Roosevelt, a former Assistant Secretary of the Navy, took the office of the presidency. The results of the exercise between the U.S. Navy's Black and Blue fleets, were mixed. The simulated attacks had certainly been mitigated by the defensive Blue fleet, however the Black fleet had scored key victories with strikes on San Pedro and San Francisco, California.
Fleet Problem XV.
Held in May 1934 in Hawaii, this was a three-phase exercise which encompassed an attack upon and defense of the Panama Canal, the capture of advanced bases, and a major fleet engagement.
Fleet Problem XVI.
Held in May 1935 in the northern Pacific off the coast of Alaska and in waters surrounding the Hawaiian Islands, this operation was divided into five distinct phases, modeled on proposals for a US offensive in the Pacific. The largest of these interwar exercises, Fleet Problem XVI was seen as a provocation by Japan, which conducted its own major exercise in response.
Fleet Problem XVII.
This problem took place off the west coast of the U.S., Central America, and the Panama Canal Zone in the spring of 1936. It was a five-phase exercise devoted to preparing the fleet for anti-submarine operations, testing communications systems, and training of aircraft patrol squadrons for extended fleet operations, and pitted the Battle Force against the submarine-augmented Scouting Force.
Fleet Problem XVIII.
This exercise was held in May 1937 in Alaskan waters and in the vicinity of the Hawaiian Islands and Midway, practicing the tactics of seizing advanced base sites—a technique later to be polished to a high degree into close support and amphibious warfare doctrines.
Fleet Problem XIX.
This operation in April and May 1938 gave the navy added experience in search tactics; in the use of submarines, destroyers, and aircraft in scouting and attack; in the dispositions of the fleet; and in the conduct of a major fleet battle. In addition, the exercise again dealt with the matter of seizing advanced fleet bases and defending them against minor opposition. Fleet Problem XIX also tested the capabilities of the Hawaiian Defense Force, augmenting it with fleet units to help to defend the islands against the United States Fleet as a whole. The last phase of the exercise exercised the fleet in operations against a defended coastline.
Fleet Problem XX.
Took place in February 1939 in the Caribbean and Atlantic, and observed in person by President Franklin Roosevelt. The exercise simulated the defense of the East Coast of the United States and Latin America by the Black team from the invading White team. Participating in the maneuvers were 134 ships, 600 planes, and over 52,000 officers and men.
Fleet Problem XXI.
An eight-phase operation for the defense of the Hawaiian area in April 1940. A diary entry written by James M. Gregory aboard the USS Astoria (CA-34) in 1940 reads, "April 2, Tue. Standing 8–12 watches in engine room. Underway 8:53 A.M. for Fleet Problem XXI. Set clocks ahead ½ hr. at 8:00 P.M. April 15, Mon. Underway to finish second half of fleet Problem XXI. Underway at 2:30 P.M. April 17, Wed. Regular routine. At Sea Prob. XXI." Navy photo available.
On May 7th, just days after the conclusion of Fleet Problem XXI, the fleet received orders to stay in Hawaii as a deterrent against Japan's growing aggressiveness.
Fleet Problem XXII.
Scheduled for the spring of 1941, but canceled for the rising threat of war.
21st Century Fleet Problems.
Fleet Problem XXIII.
Fleet Problem XXIII was the first to take place in the first 21st century after the concept was revived by Admiral Scott Swift and the US Pacific Fleet. It centered around Carrier Strike Group One, led by the aircraft carrier USS "Carl Vinson".
Fleet Problems XXIV–XXVIII.
Details on these Fleet Problems are not widely public, although the US Navy did publicize that one Fleet Problem in 2021 did include a large number of USVs and UAVs led from a "Zumwalt"-class destroyer. 