While commenting about a frigate or a destroyer, we face such questions: what is the difference between them? How can we define a warship as a destroyer? Why do we call it a frigate rather than a destroyer?
If you are not a navy crew or a navy veteran, it could be hard to distinguish two types of ships. The main differences between a destroyer and a frigate are tonnage, weapons, mission definition, capabilities, and the size to define it roughly. However, there is no standard to define a warship as a destroyer. Different countries have different definitions and ideas about what a destroyer or a frigate should do. For example, while the U.S. Navy describes a 9000 toned Arleigh Burke-class as a destroyer, Iran may call a 95-meter Moudge-class ship a destroyer.
To understand the difference clearly, we need to take a look at the history.
Frigates are the smallest of the three and possibly the smallest “blue water” ocean-spanning warship.
Initially, the Frigate was a style of design, long, low and fast. Some long fast ships of the line were called “frigate-built”. During the Classic Age of Sail, it was a full-rigged ship with a single dedicated gun deck. Depending on the nationality, there was also a minimum gun limit. They were usually used for scouting, patrol, dispatch boats for large fleets, and in independent commerce raiding. In the role of patrol and commerce raiding, they acted independently and were sometimes referred to as cruisers. The Cruiser was initially a mission, not a ship class. The Frigates would “cruise” the seas. Once armored with turreted gunned ships became the norm, the Frigate became the Cruiser. After all, you no longer had a “gun deck”, the defining feature of a Frigate. The term Frigate disappeared around the late 1800s or so. It did not reappear again until WW II.
The British needed a vessel for convoy escort. The Destroyers were serving in much the same role as the Frigates during the Age of Sail. The ocean going, long-endurance Destroyers were relatively fast and carried torpedoes to threaten and harass capital ships, like Battleships and Cruisers — and in short supply. The Patrol Boats were not fast enough and did not have the range or seakeeping qualities to escort the convoys and protect them against submarines. A middle class was created that was not as fast or heavily armed (don’t need it against submarines or planes) as Destroyers, but still faster than the convoys. It was bigger than the Patrol Boats to carry more fuel and endure the rough ocean weather and waves. The British recycled the term Frigates for this new class of ships.
In naval terminology, a destroyer is a fast, maneuverable, long-endurance warship intended to escort larger vessels in a fleet, convoy or battle group and defend them against powerful short range attackers. They were originally developed in the late 19th century by Fernando Villaamil for the Spanish Navy as a defense against torpedo boats, and by the time of the Russo-Japanese War in 1904, these “torpedo boat destroyers” (TBDs) were “large, swift, and powerfully armed torpedo boats designed to destroy other torpedo boats”. Although the term “destroyer” had been used interchangeably with “TBD” and “torpedo boat destroyer” by navies since 1892, the term “torpedo boat destroyer” had been generally shortened to simply “destroyer” by nearly all navies by the First World War.
Destroyers are much smaller than battleships but larger than frigates. They usually have one smaller gun (5 inches compared to Iowa’s 16-inch beasts) and lots of missiles, including anti-ship, surface-to-air, and cruise missiles (Tomahawks in the American case). Modern destroyers often have a helicopter pad as well, which helps with anti-submarine warfare.
The Destroyer has initially been a boat class to screen the Battleship and Cruisers, with their big, slow firing and cumbersome guns from the high-speed and nimble Torpedo Boats introduced around the late 1800s. A new class that was a bit larger, almost as fast and quick-firing smaller guns were introduced. This class was called the Torpedo Boat Destroyer, later shortened to Destroyer.
Frigate vs. Destroyer:
Today, the line between a Frigate and Destroy is blurred. In general, a Destroyer is heavier, carries more firepower, and is slightly faster than a Frigate. Frigates also tend to have more of a focus on anti-submarine missions. However, both classes are frequently multi-mission capable.
In more extensive engagements, frigates would either group up to take on larger threats, escort a larger ship to prevent it from being flanked. A destroyer is its namesake. It’s meant to kill other ships, planes, people, submarines, your pet spy dolphin.
On the other hand, Frigates more numerous and less costly to build than Destroyers.
In modern naval warfare, looking at different threats – when faced with aircraft attacks, Destroyers tend to defend themselves against a modern threat and protect any ships in the composition. Hence, longer-range weapons and sensor systems.
Frigates are not generally required to protect others, and they’re designed to defend themselves.