The post-World War II era was a time of rapid technological advancement and strategic rethinking for the U.S. Navy. Among the ambitious projects undertaken was the development of jet-powered seaplanes, a concept that promised to revolutionize naval aviation but ultimately met with a series of setbacks and cancellations.
The Martin P6M SeaMaster: A Bold Vision
The P6M SeaMaster was designed as a high-speed, long-range strike aircraft to operate from water. The prototype XP6M-1 first flew on 14 July 1955. The program soon ran into trouble, though; the prototype went to pieces in midair on 7 December 1955 as a result of a tail unit failure, and all four crew were lost. A second prototype experienced a similarly catastrophic tail failure, though the crew got out.
Despite these setbacks, the U.S. Navy gave the go-ahead for this program and went on to produce the YP6M-1 which was a pre-production model in 1957. It was in tests that it was revealed to be severely inadequate in such areas as control and engine power. The craft was initially modified with new, more powerful engines in the form of the Pratt & Whitney J75 turbojets, and upgrades to the avionics system. What resulted, the P6M-2 was a winner, but again, was killed without ever going into service, since the Navy opted, instead, to put its money into its ballistic missile submarine projects. Thus, all remaining SeaMaster airframes became razor blades.
The Convair Sea Dart: A Fighter on Water Skis
Laterally, the U.S. Navy also experimented with the Convair F2Y Sea Dart, a seaplane jet fighter to take off and land on water with retractable hydro-skis. This first flew on January 14, 1953, but ran into severe trouble with its water ski system, primarily causing oscillation and buffeting upon take-off and landing. Despite these problems, the Sea Dart did penetrate the sound barrier, reaching a speed of Mach 1.2, making it the only seaplane of its kind to become supersonic.
But despite its success and inherent promise, the Sea Dart program had a tragic setback when a test aircraft dispersed over the eastern skies on November 4th of 1954, causing momentary shock, and later killing the pilot. By the time of this masterful success, innovations in aircraft carrier design made the Sea Dart a giant in the wrong field, and after the death of the single pilot, the program was canceled in 1957. Only five prototypes were built, with four surviving to be displayed in museums.
The Convair XP5Y-1 Tradewind: A Maritime Patrol Giant
Another daring configuration was the Tradewind, a huge, transcontinental patrol bomber with turboprops, the Convair XP5Y-1, which ranged up to 5X0 feet. One of five prototypes conducted the functions the type was envisioned to do and was armed with ten 20mm autocannons in five twin turrets. However, like other examples with the Allison T40 turboprop engines, the Tradewind had awful engine reliability.
The Tradewind flew on its first flight on April 18, 1950; it set an endurance flight record for turboprop aircraft. Problems continued with its engines, and the Navy’s interest, which was beginning to become all the more focused on the jet-powered SeaMaster, a combat version of the Tradewind was canceled. Outstanding orders were converted to the transport version, the R3Y, which flew briefly before retirement in 1958.
The much-heralded entry by the U.S. Navy into the field of jet-powered seaplanes ended in disappointment, just like the rest. These three programs alone, SeaMaster, Sea Dart, and Tradewind combined to come to over $500 million in 1950s money before being shelved as technology advanced and strategic priorities changed.
In the words of the military historian William Trimble, the Seaplane Striking Force “is a cautionary tale. Planning and strategy have to be guided by the lessons of such ambitious but ultimately flawed schemes, lest they build the proverbial spaceship on their predictions. Their legacy stands as a reminder of the weaknesses and dangers of military innovation gone complex.