Taking flight from the ocean, lakes and fjords, warfare seaplanes provided some of the most exciting moments in aviation in the Second World War. Like their fleet counterparts, they came in flying boat or floatplane form and could deliver their bombs, torpedoes and guns far from established landing strips. They played a key role in nearly every theater of operations, hunting ships and submarines, performing recon and providing backup for troops, and rescuing downed aircrews. Using the water itself as a base of operations gave forces a new tool for using the skies to dominate the earth and water.

During the course of the war, seaplanes served a wide range of vital roles from high altitude, long-range maritime patrol, and anti-submarine warfare, to high-risk air-sea rescue operations. Some, large water-borne aircraft armed with heavy armament and capable of traveling thousands of miles, and others tiny observation plane launched from a warship. Their designs ranged from the enormous to the diminutive, but all proved how important water-borne aircraft could be in times of conflict. Here are ten of the most impressive seaplanes to see WWII.

1. Beriev MBR-2

From his own design in 1930 the 27-year-old Georgy Beriev created the all-wood prototype of the Beriev MBR-2, before it flew from the Black Sea for its first time on 30 April 1932. By 1937 it had become the most common maritime aircraft in the Soviet Union. Its simple and easy to build construction, along with flexible design meant it could be effective in difficult conditions and undertake many types of tasks, becoming a key part of Soviet maritime aviation during and before the Second World War.

Beriev MBR-2 Operational Highlights:

• Designed by Georgy Beriev
• First flew in 1932
• 1,365 aircraft produced
• Soviet maritime reconnaissance aircraft
• Multi-purpose flying boat

The MBR-2 first saw combat during 1939’s Winter War with Finland, where it excelled in severe field conditions. It flew reconnaissance to the Barents Sea in the north and bombed coast installations and Finnish shipping. As the aircraft’s soundness was realized against fighters, the heavily built twin-prowled amphibian was relegated to night strikes, search and rescue, and transport duty, eventually in the Pacific against Japanese shipping. Postwar service saw the MBR-2 stick around in support of night strike missions during the Korean War; the aircraft’s lengthy service history and versatile missions was a testament to the flexibility of Soviet water-borne aviation.

2. Martin Mariner

1,366 aircraft of the PBM Mariner were built, making it the second most numerous flying boats ever built. Prior to the full-size aircraft being built, the aerodynamics of the flying boat’s configuration were tested using a smaller manned testbed that was powered by two Chevrolet car engines called the “Tadpole Clipper”. Early aerodynamics issues prompted modifications to the tailplane and to the inherently inward-canted tailfins which are characteristic of the Mariner.

Martin Mariner Mission Highlights:

• 1,366 aircraft produced
• First flew in 1939
• Twin-engine patrol bomber
• Sank multiple U-boats
• Supported rescue missions

During the war, Mariners sank at least 10 U-boats and also saw much action across the Pacific. Their dark bodies led to their being dubbed Nightmares as they carried out night-time interdiction sorties. Later versions carried provisions for Jet Assisted Take-off bottles to enable shorter take-offs in rough sea conditions. Mariner versions went on to see service during the Korean War, carrying out patrol and rescue sorties long after the conclusion of WWII and even the United States Coast Guard operated Mariners as part of their long-range search-and-rescue fleet, the years of service only showing the durability and flexibility of the basic flying-boat design.

3. Short Sunderland

Designed as a military version of Imperial Airways’ prewar Short Empire airliner, the Short Sunderland became one of Britain’s most iconic flying boats of the Second World War. Because of its civilian origins, the Sunderland had a roomy, comfortable interior, with a two-deck fuselage, complete with kitchen, wardroom, and bunks. This abundance of space meant that the Sunderland was suited to some very long-range missions, or those requiring a large crew or a lot of equipment.

Short Sunderland Combat Highlights:

• Approximately 2,700-mile range
• Powerful defensive armament
• Credited with 28 U-boats
• Spacious two-deck fuselage
• Famous “Flying Porcupine” nickname

In combat, the Sunderland combined the advantage of long range with powerful armament, and was credited with 28 U-boat sinkings. The Germans developed a healthy respect for the aircrafts’ defence, and affectionately called it the “Flying Porcupine”. A Sunderland was able to single-handedly turn back six Ju 88 heavy fighters in April 1940, and its large spacious hull was a boon in cases of emergency evacuations, in one case with 82 on board taking off from Crete in May 1941. The aircraft was useful for other roles, and continued to serve in the front-line with New Zealand until 1967, an extraordinarily long service life for a World War 2 era flying boat.

4. Vought OS2U Kingfisher

The Vought OS2U Kingfisher was introduced into service in August 1940 as the United States Navy’s first Monoplane-based Catapult aircraft. Rex Beisel designed a number of interesting production and operational innovations for the Kingfisher, one of which was the construction of the aircraft to standard sizes so that it could be assembled to employ one or the other of the Wheeled or 24 ft. Long ‘Floats’ with ease.

Kingfisher Naval Highlights:

• First flew in 1938
• Catapult-launched monoplane
• 1,519 aircraft produced
• Float or wheeled landing gear
• Observation and rescue duties

The Kingfisher became the designated gunnery-spotting, observation, and air-sea rescue machine carried by every American capital ship; battleships carried three, Iowa’s four. One of the more notable was when it rescued World War I ace Eddie Rickenbacker and crashed B-17s. It would taxi across the Pacific Ocean for around forty miles with men sitting on its wings. 1,519 Kingfishers were produced, with many given to countries allied with the US, such as Australia, Britain and the Soviet Union; a surviving Cuban example would also have a career as a ground attack machine during the revolution of 1959 with Fidel Castro at the controls.

5. Supermarine Walrus

History, Specifications, and Technical Data Purpose and Desinged by R.J. Mitchell, the Supermarine Walrus was a very unusual biplane, incorporating many of the most advanced design features of the day. It was the first British aircraft military to combine a retractable undercarriage, fully enclosed cockpit and a metal fuselage in a single aircraft. Designed to operate from warships, the aircraft could be catapult-launched from cruisers and battleships and was capable of operating in heavy seas.

Supermarine Walrus Rescue Highlights:

• Designed by R.J. Mitchell
• First flew in 1933
• Catapult-launched from ships
• Equipped with ASV radar
• Rescued about 1,000 aircrew

The early years saw the Walrus perform maritime patrol and anti-submarine roles, and after receiving ASV search radar in March 1941, was able to locate ships over large stretches of ocean. Its most important work, however, was on land-based air-sea rescue missions. Over the course of the war, it was credited with rescuing around 1,000 aircrew, and the aircraft was particularly useful in retrieving crews and other personnel stranded at sea. Its appallingly slow landing speed meant that it could even land from a carrier without an arrest or hook, and it continued on in service after the war, its air-sea rescue duties being taken over by the new helicopters.

6. CANT Z.506 Airone

The CANT Z.506 Airone has its origins as a record-breaking commercial aircraft before evolving into the Z.506B version of the airframe that would be adapted for military use. The military aircraft had the added benefit of more powerful engines, higher cockpit canopy and a long ventral gondola housing the bomb aimer, bombload and rear defensive gun. Despite being built mainly of wood, the Airone was still well suited to operating in the rough seas.

CANT Z.506 Mission Highlights:

• Trimotor floatplane design
• First flew in 1935
• Rough-sea operating capability
• Maritime patrol and bombing
• Dedicated rescue version

The Airone was capable of operating over the coast in the assault version, over shipping and as a long-range maritime patrol aircraft, and even continued to operate after the 1943 Italian armistice with the Allies, operating alongside German aircraft. Perhaps the most important of its variants, was the Z.506S, which was used for air-sea rescue work, rescuing 231 people between 1940 and 1942; even though these aircraft were painted in large red-cross markings, the British Regular army “Beaufighter” fighters still continued to attack them, and in an extraordinary event in July 1942, some airmen being rescued from the sea managed to seize the Italian crew and force the Italian pilots to fly a Z.506B to Malta. With its range, water-operating capabilities and flexibility, this craft was probably one of the best of its era.

7. Blohm & Voss Bv 138

The Blohm & Voss Bv 138 in brief: Nicknamed “Der Fliegende Holzschuh” (“The Flying Clog”) due to the shape of its hull, the Bv 138 was the mainstay of German maritime patrol aircraft. This odd looking aircraft featured a curious twin-boom design, but its odd shape hid an extremely rugged and dependable aircraft. The Bv 138 was heavily armed and designed to carry out long-range patrol missions in areas where land-based aircraft would encounter difficulties.

Bv 138 Maritime Highlights:

• German long-range patrol aircraft
• Distinctive twin-boom design
• 2,670-mile range
• Efficient diesel engines
• Could sweep magnetic mines

One of the Bv 138’s most bizarre attributes was its use of extremely fuel-efficient diesel engines, which gave it a range of approximately 2,670 miles. Additionally, its range could be stretched even further by refueling from German U-boats in mid-air; a Bv 138 was refueled 4 times by U-255 during a mission in 1942 (Operation Wunderland). It could be operated right from the water or launched from a seaplane tender. Additionally, it was used as an aerial minesweeper, having a 40′ electrically charged degaussing ring mounted in the fuselage and capable of detonation of magnetic mines while the aircraft was cruising at low altitude.

8. Spitfire Floatplane

The concept of a Seaplane conversion of the Supermarine Spitfire was first introduced during the Norwegian campaign when the shortage of sufficient airfields gave a real operational requirement for an aircraft that could operate on water. Float fittings were added to a Spitfire Mk.I, but before the aircraft could actually operate in combat conditions, Germany occupied Norway and the aircraft was subsequently converted to standard landing gear. This experiment was revisited a decade later when the world’s most famous fighter was being considered for service in other roles.

Spitfire Floatplane Speed Highlights:

• Floats adapted to Spitfire
• Norwegian campaign inspiration
• Pacific operations considered
• Final conversion in 1944
• Reached 377 mph

The idea came back to life in late 1941, when work began on a Mk.V airframe, although this was to be used in the Pacific theatre. Plans were later drawn up for three Mk.V floatplanes to operate from clandestine bases on Aegean islands, only for the Germans to invade the bases before the aircraft could be put to use. A final design was completed in 1944, with floats applied to a Spitfire Mk.IX (powered by a Merlin 45), which reached a phenomenal 377 mph (607 km/h) still making it the fastest ever floatplane, and the third-fastest floatplane ever. The whole project was eventually abandoned in late 1945, but not before a fascinating chapter of the Spitfire story.

9. Kawanishi H8K

The Kawanishi H8K (Allied reporting name: Emily) was one of the best second world war flying boats and the fastest and heavily defended flying boat of any combatant. Under the project management of Shizuo Kikuhara, the aircraft had a deep relatively slender hull and shoulder-mounted wings. The earlier prototypes suffered from a severe proposing and spray problems with the engines, but the problems were radically overcome by a complete redesign resulting in very efficient long-range Pacific-capable hulls.

Kawanishi H8K Defense Highlights:

• First flew in 1941
• Long-range maritime patrol
• Up to 4,409-pound bombload
• Five 20-mm cannons
• Five 7.7-mm machine guns

The H8K was employed in maritime reconnaissance, patrol, anti-submarine warfare, and bombing missions. It could be armed with Type 91 torpedoes or up to 4,409 pounds of bombs, and its high speed, substantial armor, numerous 20-mm cannon and 7.7-mm machine guns, and fire suppression system in its fuel tanks made it difficult for Allied pilots to take down. It was also capable of long-range missions like its first combat mission in March 1942, when it flew in a second raid on Pearl Harbor. The H8K’s enormous range, as well as its speed, protection, and armament, made it one of the deadliest waterborne aircraft of the war.

10. Consolidated PBY Catalina

The Consolidated PBY Catalina emerged as one of the most important and widely used WWII seaplanes. While it was originally built as a long-range patrol bomber aircraft, the twin-engine airplane could easily fly 2,500 miles and still was capable of carrying significant armament even with two engines. Its wide-area-range of operation made it essential for open ocean vessel tracking and anti-submarine operations, and its amphibious ability increased the number of operating locations.

Catalina Wartime Highlights:

• Approximately 2,500-mile range
• Twin-engine flying boat
• Anti-submarine warfare specialist
• Spotted the Bismarck
• Destroyed 40 submarines

Catalinas were used in many roles during World War II, from spotting the Bismarck, witnessing Japanese landings in Malaya, and spotting the fleets prior to Midway. An August 1941 RAF Catalina in conjunction with HMS Vascama was involved in sinking U-452, and Catalinas went on to be credited with destroying 40 submarines-more than any other flying boat-and pioneered the first U.S. Navy air-to-air victory, when a bow gunner shot down a Mitsubishi Zero while evacuating Americans from the Philippines in December 1941. These ten incredible aircraft demonstrate how sea-based aircraft changed naval aviation, from reconnaissance, to anti-submarine operations, to bombing, to transport, to mine-clearing, to observation and rescue, from the endurance-focused Catalina and Sunderland to the ship-based Kingfisher and Walrus, to the long-range H8K and Bv 138, to the floatplane Spitfire-all expanding the canvas of water on which modern air forces could operate.