One of the oldest forms of naval aviation became extinct approximately seven decades ago: catapult float planes. Not carrier-based, it instead was seen as a supplement for a battleship or cruiser’s gunnery. 

The first operation of aircraft was from traditionally designed warships. Unfortunately, troublesome ramps interfered with the working of deck guns. The Navy asked pioneer designer Glenn Curtiss, perfecting his aircraft designs at a new camp on North Island, to demonstrate how his new “hydroaeroplane” could work with a warship with little or no modification to accommodate the airplane. 

On Feb. 17, 1911, Curtiss taxied his prototype floatplane to the cruiser USS Pennsylvania, anchored in San Diego Bay. The ship’s boat crane hoisted Curtiss and his machine out of the water and onto the deck. Minutes later, the process was reversed. After the plane was set back into the bay, Curtiss returned to North Island. Although brief, this proof-of-concept demonstration resulted in the Navy’s commitment to purchase its first aircraft from Curtiss.

Two Curtis SOC scout planes on board the battleship USS Tennessee.

These new aircraft were envisioned as scouts at sea, but the realities of taking off and landing on the high seas next to a ship were problematic. Naval designers were forced to look at a catapult system as a means of sending an aircraft aloft directly from a ship’s deck. In 1915, an elevated track was installed above the guns on the cruiser USS North Carolina that pulled aircraft to flying speed over the catapult’s length. An aviation first.

Though placing aircraft on ships was inconvenient, a shift in gunnery doctrine demanded a comprise between the surface navy and the aviators. The trouble was in hitting a moving target several miles away that was little more than a speck in the open ocean. Tests soon demonstrated that having an aerial observer near the target in radio communication with the shooting ship could adjust the fall of shot more quickly and accurately. With this in mind, accommodating aircraft aboard battleships and cruisers became an urgent necessity.

Experimentation continued to improve the efficiency of catapulting aircraft from ships. The use of compressed air propulsion was nearing its limits as aircraft became heavier. A breakthrough occurred when explosive propellent provided enough energy for a safe launch and required only minutes to ready the catapult for the next aircraft. By 1925, black powder charge catapults became common on large gunnery platforms.

With the launching issue cracked, the problem of recovering a spotter plane remained. Over the spring of 1933, tests were conducted in streaming a flattened net just below the water’s surface alongside the receiving ship. A hook jutting beneath the seaplane’s center float permitted a snag as the aircraft taxied up and over the net. With the aircraft now being carried along by the net, the flight crew focused on connecting the aircraft to the ship’s crane. This technique worked consistently and swiftly became standard in the fleet.

Despite the hazards of employing aircraft from such warships, the exploits of the floatplane crews more than made up for the dangers. Although carrier aviators now garnered most of the attention, their seaplane colleagues flew vital but mundane missions including spotting, scouting, anti-submarine patrols, and daring rescues.

In 1942, Eddie Rickenbacker, America’s ace of aces from World War I survived a ditching in the South Pacific with five other men. After three weeks adrift they were rescued by an OS2U Kingfisher floatplane. Rickenbacker and his cohorts were lashed to the Kingfisher’s wings to endure a rough ocean taxi over the wavetops to meet with an approaching PT boat.

During the various amphibious invasions in the Mediterranean and France later in the war, naval gunfire was vital for retrieving desperate situations on the beach, and aerial spotting was crucial. However, German fighter and anti-aircraft defenses were formidable, and delicate floatplanes incapable of even exceeding 100 knots were far too vulnerable to being shot down. U.S. Navy spotter pilots transitioned to higher performance aircraft like the P-51 Mustang and the British Spitfire. Flying from airfields alongside their Army Air Force counterparts, the Navy spotters delivered timely warnings of German tank movements, guiding devasting naval shellfire into the formations, or in pinpointing the locations of concealed artillery emplacements. The operational usage for the floatplane continued to diminish.

As World War II drew to an end, a new form of aviation arose that would ultimately put an end to catapult floatplanes. The new and highly versatile helicopter promised shipboard capabilities without the bulky catapult or crane equipment. Additionally, with its hovering ability, the new rotary wing aircraft could fly from ships of all sizes. As helicopter performance steadily improved, the last floatplane squadron at Naval Air Station Norfolk shifted to helicopters. On July 4, 1949, the era of the “slingshot fliers” was over.

A Curtis SOC scout plane is loaded onto a catapult aboard the cruiser USS Minneapolis.

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