Name: Is The F-35 Worth $115 Million?
Uploaded: 2021-06-09T08:42:27.000Z
Duration: 23 min 49 s
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This year the F-35 is finally set to close it's 27 year development phase, and move

towards high volume manufacturing. The culmination of 27 years of design and development from

its manufacturer, Lockheed Martin. 27 years of development, crossing the finish line in

the midst of a political power struggle in America. This is after all, the most expensive

weapons system in the history of humankind.

Costs have inflated as a result of the America military-industrial complex, where the intertwining

of politics, economy and the military industry encourages companies like Lockheed Martin

and Boeing to not vertically integrate their companies, as a means of spreading jobs across

America and thereby increase political support for these programs and the politicians that

approve them in congress to win contracts. We could deep dive into these muddied waters

of politics, but this channel is about engineering and the development costs of the F-35 would

be astronomical even without these issues, so let's explore the design of this plane

and see whether it's price tag is really worth it.

From the start, the F-35 sought to be the jack of all trades. [1] An air superiority

machine to replace the Air Force's F-16s and A-10s. A stealth fighter, taking the lessons

learned from the B-2 program and improving upon Lockheed's previous ventures into stealth

technology, with the F-22 Raptor and the F-117 Nighthawk. A carrier capable fighter to replace

the F/A-18 Hornets of the Navy, and perhaps most audacious of all, it would take on the

challenge of vertical landings, taking over from the British AV-8B Harrier.

Taking on all these advanced technologies and combining them into one plane was never

going to be an easy, or cheap task, and the program was made even more expensive by what

was initially intended to be a cost saving measure.

This plane would be developed as a joint venture between 3 US Military branches. The Air Force,

Navy and Marines. A single plane for each branch of the military. The program was named

the Joint Strike Fighter, and it's goal was to produce a next generation plane that

could replace fighter, strike and ground attack aircraft of not just the United States, but

all of its Allies. Unlike the F-22 Raptor, which is an US Air Force exclusive plane,

the F-35 would be commercially available.

The JSF program began life as a competition, between McDonnell Douglas, Northrop Grumman,

Lockheed Martin and Boeing. With Lockheed and Boeing going on to develop prototype aircraft

as finalists in this competition, both eager to win what was sure to be one of the most

lucrative contracts they would ever sign. Boeing's aircraft, the X-32, was an odd

looking aircraft. Featuring a massive single air intake that made it less VTOL and more

VLOL. [2]Its looks alone may have stopped it from winning this valuable contract, but

what really held it back was Boeing's decision to create two prototype planes. One capable

of supersonic flight, and one capable of vertical take-off, [3] using the same vectored thrust

as the Harrier, which it was supposed to be replacing.

The engine used in the Harrier is similar to a traditional jet engine in that it consists

of a low pressure compressor fan, a high pressure compressor, a combustion chamber, a high pressure

But it's outlet nozzle placement is anything but traditional. 2 outlets are placed immediately

after the low pressure compressor, with another two ducting air from the higher pressure turbines.

In vertical thrust mode, the nozzles point downwards, and allow the plane to balance

The Harrier was not an easy plane to control in this flight mode and on more than one occasion

turbulence from it's own downwash caused the plane to flip over onto the cockpit during

A large part of these control issues can be attributed to the proximity of the control

nozzles to the centre of gravity of the plane. Giving them less mechanical advantage to manipulate

the planes attitude. The Harrier did have small roll control nozzles on the tip of each

wing, but the control for these were entirely manual. Placing the incredibly unstable control

mechanism into the hands of a human that needed to focus on various other factors when landing.

The X-32 used many of the same techniques to achieve vertical thrust, but improved on

many of the Harriers short comings. Instead of using the same nozzles for cruise and direct

lift, the X-32 would close valves for each when needed. In normal flight the cruise nozzles

would open, allowing the thrust of the jet engine to be directed efficiently through

the rear of the aircraft. Then, during transition, this nozzle would close and force air through

They placed larger roll control nozzles further from the planes centre of mass and also employed

a cold air screen placed just forward of the lift nozzles. [5] This was intended to stop

hot turbulent air from the direct lift nozzles from entering the front intake, which was

a massive issue for the Harrier as it landed. Jet engines need cold and smooth air to operate

at maximum thrust, which was difficult to get when landing and directing the entirety

Despite these improvements, Lockheed ultimately won the contract. Impressing the JSF program

with their lift fan system. The engine thrust here, once again, exits a single exhaust nozzle

during normal flight, but when the show begins, the X-35 was capable of some incredible transformer-like

Hatches opened on the top and bottom of the aircraft, revealing two contra -rotating fans.

Another 2 little doors open beneath the wings, exposing two additional exhaust ports that

control the planes roll. Finally, as the plane begins to slow down, the cruise nozzle will

begin to pivot downwards, transitioning the remaining thrust of the jet engine from horizontal

to vertical. [6] The lift fan solved many of the same issues that plagued the harrier.

The lift fan produced the majority of the vertical thrust and it did not heat up the

air significantly in the process. The roll control had significantly more mechanical

advantage and divvied the majority of the control over to a computer.

Perhaps most influential in their success to winning the contract, this prototype was

capable of both vertical landings and supersonic flight. This was the kind of innovation the

Joint Strike Fighter program was looking for.

The lift fan is essentially a turboprop engine like something you would find on an Osprey.

The propellers are driven by a drive shaft connected to the jet engine turbines, which

can be disengaged during normal flight. This means the lift fan is deadweight during cruise,

but what it adds in weight, it more than makes up for in lift.

Combined these propulsion methods can produce 185 kilo Newtons of lift. [7] The Harrier

could only manage 106 kN [8]. This increase in direct lift capabilities was vital to making

the F-35 a worthy successor to the Harrier, as one of the Harriers greatest weaknesses

was its limitations in maximum take-off and landing weight.

The Harrier, like the F-35B, mostly operated in short take off and vertical mode. The Harrier

would point all four of its nozzles at about a 45 degree angle, allowing it to produce

both horizontal and vertical thrust to take off from shorter runways. This allowed it

to take off with considerably more weight than it could land with a vertical landing.

The empty weight of the F-35b may be 13,154 kilogram [9], compared to the 6,340 kilograms

of the Harrier [10]. But it more than makes up for that with a maximum take-off weight

of 31,800 kilograms compared the Harrier's 14,100 kilograms. That's an extra 11 tonnes

of weight available to the F-35 for fuel and ammunitions. Something the Harrier had little

space for. So, the F-35 is more than a worthy successor to the Harrier. A plane which fetched

about 24 million dollars per unit in 1996, or about 39 million adjusted for inflation.

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Is The F-35 Worth $115 Million?

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