In the spring of 1969, the U.S. Navy begins testing its newest vessel.
But this is no ordinary ship.
It doesn’t float on top of the water.
It can lift itself right out of it.
And because of that, it can do what no other ship can.
Move at unheard of speeds, operate in rough seas, and out-maneuver anything else on the water.
Sixty years ago, the U.S Navy set out to build ships that could fly.
In the 1960's, the U.S. Navy was the most capable in the world.
Ready to project power to any corner of the planet.
But military planners were growing concerned about a new threat from the Soviet Union.
Soviet nuclear-powered submarines were becoming faster, more capable,
and being built in large numbers.
The latest generation under development, would reach an incredible 41 knots fully submerged.
Speeds that would allow them to hunt down any ship in the U.S. fleet, even outrun torpedoes.
They would also dive to record depths, making them extremely difficult to intercept.
With their new submarines, the Soviets could shadow American carrier groups anywhere in
the world and launch a devastating strike at a moment's notice.
Destroyers and frigates might detect the incoming subs using sophisticated sonar, but they would
have no way of closing the distance to engage them.
The Navy would need to develop much faster ships.
And they would do it by turning to technology that was already 50 years old.
In 1906, an Italian engineer devised a way to make a boat go a lot faster.
Using a series of foils (essentially underwater wings) his boat could lift out of the water
as it accelerated.
Reducing drag, allowing for much higher speeds.
It was called a hydrofoil.
And a decade later, inventor Alexander Graham Bell improved on the design, building a hydrofoil
that set a new all time marine speed record, demonstrating the awesome potential of the technology.
In the decades that followed, the hydrofoil was progressively improved and in the 1950’s,
commercial hydrofoils were entering into service.
But hydrofoils received little attention from the U.S. Navy.
Because for the most part, they were only suited for calmer waters.
Not out on the ocean where the Navy needed them.
That's because most hydrofoils worked by skimming close to the surface.
A design that made them stable but easily affected by waves.
Limiting their use to calmer lakes and waterways.
But there was a second way to build a hydrofoil.
By positioning the foils entirely underwater, they would be unaffected by the waves above.
Allowing for smooth operation even in rough seas.
The problem was, the design wasn't dynamically stable.
Meaning somehow, the foils would have to be continually adjusted to keep the craft level.
And it wasn't until the 1960’s that the technologies needed to make it work really
came into existence.
It was around this time the U.S. Navy realized that ocean-going hydrofoils could be the answer
to the Soviet challenge.
With their speed and ability to operate in virtually any condition, hydrofoils could
chase down Soviet subs, making them ideal for anti-submarine warfare.
Plainview, the Navy’s fourth hydrofoil, was built to evaluate the potential of large,
ocean-going hydrofoils.
By 1970, the U.S. Navy had four prototype hydrofoils under evaluation with the two largest being
the 110 ton USS High Point and the 320 ton Plainview, at the time, the world's largest
But on the drawing board were conceptual designs for even larger ships, ranging all the way
up to twenty-five hundred tons.
Destroyer-escort sized hydrofoils that could even be equipped with helicopters.
But before any of that, each of the Navy’s prototype ships would need to be put through
their paces to evaluate various foil configurations and propulsion systems.
Hydrofoils are expected to operate in the open ocean where they may be subjected to
severe storms.
The ships were also fitted with the latest armament to test their combat potential, including
operating guns while moving at high speed, launching torpedoes, and firing anti-ship
and anti-aircraft missiles.
For the largely traditional Navy, hydrofoils were a radical departure involving new technologies
that blurred the lines between naval and aviation.
And nowhere was this more apparent than on Plainview.
At hullborne speeds, Plainview operated much like a conventional ship, powered by a pair
of 600 horsepower diesel engines.
But when it needed to get up and go, Plainview's crew would hydraulically lower the foils and
run up a pair of fourteen thousand horsepower gas-turbines.
The two jet engines were largely the same ones used on fighter jets like the F4-Phantom.
They transferred power through an intricate transmission system which drove two super-cavitating
titanium propellers at the end of each foil.
With this setup, Plainview could fly at over 50 knots.
But the ship was designed to be upgraded with an additional set of jet engines and a super-cavitating
foil system which would allow for speeds of up to 90 knots.
The ship’s foils were connected to an automatic control system which functioned much like
the autopilot on an aircraft.
The system continually adjusted angle of attack to maintain level flight using readings from
an sonic height sensor, accelerometer, and a set of gyros, allowing Plainview to maintain
high speeds even in ten-foot waves.
As the most ambitious of all the Navy’s experimental ships, Plainview would help lay
the groundwork for large, ocean-going hydrofoils.
The Navy issued requirements for Planview in 1960 with Grumman winning the bid for design
in 1961.
Two years later, the project was transferred to Lockheed for construction.
And when the ship launched in the summer of 1965, it was hailed as a technical marvel
and an exciting sign of things to come.
But beneath the surface, there was already a sense that things weren't going to go according to plan.
For starters, a series of strikes at Lockheed Shipyards delayed the program.
It meant Plainview wouldn't make its first high-speed test run until March of 1968 And
even then it was plagued with deficiencies that should've been sorted out at a much earlier stage.
By 1969, the ship was already three years behind schedule and 100% over budget.
At that point, the Navy decided to take matters into their own hands, accepting the unfinished
ship to try to work out the issues themselves.
But it would be easier said than done.
Each of the Navy’s four prototype ships were one-of-a-kind, experimental designs.
It meant development resources would have to be stretched across all four, further slowing progress.
In May of 1974, the Navy sent Plainview to drydock to undergo a major two-year overhaul.
Enhancements included a more refined hydraulic system and an advanced digital autopilot.
After the overhaul, Plainview was a better ship.
More capable out at sea and much more reliable.
But many in the Navy had already grown impatient with the ship’s protected development, while
others wanted nothing to do with hydrofoils.
For all their advantages, hydrofoils also had a few critical drawbacks.
Compared to conventional warships they were weight critical, requiring aluminum hulls
which were neither as strong nor as cost-effective to build.
Weight limitations also meant hydrofoils would be less armored and carry less armament.
Their complex foils and dual propulsion systems would make them less dependable and more maintenance
heavy, consuming a greater share of the Navy's budget.
And when it came to anti-submarine warfare, by the mid-1970s there were more practical
alternatives.
The Navy had made huge strides in utilizing aircraft to track and hunt down submarines,
which were more effective and economical to operate
It meant the case for large ocean-going hydrofoils like Plainview no longer seemed as compelling
as it once was.
Pegasus PHM-1 is the first ship in a new class of hydrofoil.
After more than a decade of research and development, the U.S. Navy did eventually put a hydrofoil
into production.
At 240 tons, the Pegasus class was significantly smaller than Plainview and nowhere near the
size of the large oceangoing hydrofoils once studied by the Navy.
Instead of hunting down submarines, Pegasus ships were designed for coastal patrol on
smaller seas like the Baltic.
At one point there were plans to build 44 ships, with German and Italian Navies showing interest.
But after extensive research and development only Six entered service with the U.S. Navy.
And they were retired after just 10 years due to high operating costs and lack of a
useful mission.
In 1978, the Navy's budget for experimental hydrofoil development was suddenly cut from
2.2 million dollars a year to zero, sinking any prospects for further hydrofoil development.
In the 1960s, faith in technological progress was at an all time high, with an endless stream
of fantastical concepts that would allow us to travel a lot faster.
But one idea that seemed destined to become reality was supersonic travel.
Billions were poured into developing technologies for a new generation of airliners that would
travel two or even three times the speed of sound.
Making a round trip to any corner of the globe possible in less than a day.
In my next big project, I’m going to explore why the dream of mass-supersonic air travel
never became reality.
And imagine what the world would have looked like if it did, by creating an alternative
universe and an entirely new kind of Mustard of video.
Nebula is where you can watch more mustard videos from fantastical concepts to iconic aircraft.
My most ambitious video to date covers the story of the legendary B-2 Spirit, a plane
engineered to fly into any air space in the world, no matter how heavily defended.
Nebula is full of exclusive content from other creators, like Real Engineering, Wendover,
and Real Life Lore.
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A recent favorite of mine is ‘Dornier - Pioneer of Aviation’ , a fascinating two part documentary
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