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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

turbine and a low pressure turbine.

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

precariously on these 4 columns of air.

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

landings, killing the pilot. [4]

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

the direct lift nozzles.

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

of your thrust directly at the ground.

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

changes.

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.

[10]

So, incorporating VTOL to the F-35B was just one of many design challenges that pushed

the price of the program up. Ironically, despite Boeing's duel prototype entry being a sticking

point for the JSF program. The F-35 now comes in three variants. [11]

Each tailored for different branches in the US military. The F-35A is customised for the

US Air Force, and as such has been designed to take off from conventional runways. Allowing

it to scrap much of the heavy equipment needed for the F-35B, the Marine's variant.

The Marines do not operate out of large aircraft carriers, like the Navy, and as such their

ships, like the Wasp-class amphibious assault ship, have been often referred to as helicopter

carriers. As no plane, other than a Harrier or Osprey, have been able to use them. This

is not the case for the Navy, who have large aircraft carriers at their disposal.

The final variant is the F-35C, which has been designed to satisfy the Navy's requirements,

having wings that are about 40% larger than either of it's sister variants and it's

landing gear is much heavier and . Both these features were included to allow it to land

and take off from aircraft carriers, without the need for the vertical propulsion of the

F-35B. The larger wings not only allow the F-35C to have the largest fuel capacity of

the 3, but also give it much better lift at slower speeds. Making landings and takeoffs

much easier on the deck of an aircraft carrier, while the heavier landing gear allows the

plane to survive the rough landings associated with the arresting wire landings on aircraft

carriers. The F-35C also incorporates folding wing tips to allow for neat storage inside

the ship.

This expansion into 3 variants has been a huge source of increased costs, and the program

likely could have dramatically reduced on spending had it just designed three different

planes for the 3 different branches. Trying to squeeze the needs of these 3 military branches

into a single airframe was never going to be an easy task for the R&D division of Lockheed

Martin, and forced them to make some concessions in design that have limited it in other areas.

The brunt of the criticism directed at the F-35 is its shortcomings in its dog fighting

capabilities. Headlines of the F-35 losing simulated dog fights to the cold war era F-15s

and F-16s grabbed many people's attention, and were used to detract from the F-35s advancements.

[12]

We only knew about these issues as a result of report that leaked to the press. Let's

take a look at that report [13] to see what this test pilot thought about the F-35A he

flew.

The primary flaw this pilot highlight was the F-35As poor energy maneuverability. Meaning

the F-35A struggled to maneuver without expending a significant amount of its kinetic energy,

which is a problem I discussed in more detail in my fighter jet instability video. The primary

design aspect the pilot pins this on is the smaller wing area and weaker afterburner thrust

of the F-35 in comparison to the F-15E he was accustomed to. Essentially their issue

with the F-35 was that it depleted it's kinetic energy store quicker than it's competition.

We have no reason to believe this pilot was wrong in his findings, so what does this mean

for the F-35? It is important to note that this was not a fully functional version, missing

software enabling the plane to detect it's foes before they can detect it and was missing

it's radar absorbing paint. [14]

On top of this, the F-35 is not short of trained military aviators who praise the F-35. [15]

Like US Marine Corps Major Dan Flatey, who helped design the combat training program

for F-35 pilots, and he has chalked up these issues to old habits of pilots who have spent

significant portions of their lives dedicated to older generation planes, which were designed

with a different philosophy. Since then the F-35 has performed phenomenally in simulation

with reports up to 20-1 kdrs. [16]

Other pilots, who have had more time to become accustomed to the F-35 had more positive things

to say. Like Jon Beesley, the chief test pilot of the F-35, with 22 years of experience as

a test pilot at Lockheed Martin and was involved in the development of the F-117 Nighthawk

and the F-22 Raptor. He claims that the F-35 can out maneuver any

US fighter except for the F-22, which was designed specifically as an air superiority

machine and AGAIN is not available for purchase outside of America and actually has a higher

unit cost than the F-35 at about 150 million dollars. It's hard for me to make a judgement

call on this because I have as little information as any other civilian, but honestly, outside

of this one report most pilots who have flown with the F-35 sing its praises.

Jon Beesley also makes an important note. Air Combat has always relied on stealth, whether

it was world war 1 pilots diving with the Sun at their backs or modern fighters using

advanced radar masking design.

Because, in the grand scheme of things. In a dogfight the real stat that matters is who

sees and shoots first, and the biggest factor that contributes to that today are on board

sensors and stealth.

The thing that really sets the F-35 apart is it's suite of sensors and computer guidance

systems, which have been integrated with the user interface of the aircraft unlike any

other plane in history of mankind, while sharing that information with the entire force. This

is what truly makes this plane something to be feared, and it all starts with this. A

little transparent faceted sensor suite [17], containing the infrared imaging and tracking

equipment of the aircraft, but those are not your typical windows. Those are made of sapphire,

a notoriously expensive gemstone. One of the few materials that is both hard and durable,

but also transparent to a broad range of wavelengths. The imaging data from these sensors can even

feed into the pilot's helmet visor, which has been enhanced with augmented reality technology.

[18]This helmet alone costs four hundred thousand dollars, and enables the pilot to look straight

through the aircraft, and see at night without having to wear clumsy night vision goggles.

The helmet also feeds in data from the multitude of other sensors like the advanced high frequency

radar in the nose of the plane, along with data received from sensors from other aircraft

and ground based units. The data does not feed into the pilots AR Helmet unfiltered

though, it first passes through the onboard computer which performs all the necessary

filtering and data analysis and only presents the pilot with the information they really

needs. This technology is so powerful that even an unarmed F-35 would greatly boost the

combat effectiveness of its allies, but detection is just one step of that goal of shooting