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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
first. Not being detected is just as important.
Incorporating stealth was just another challenge, and is likely the source of much of the unexpected
costs. Let’s first clear something up, despite what you may have otherwise heard, stealth
does not render a plane undetectable. Short of not physically existing, everything is
detectable. If we can find and analyse planets billions of lightyears away, we can detect
a plane flying directly overhead. Stealths purpose is not to make the plane invisible,
it serves to complicate and delay the enemies detection of an aircraft.
Stealth has proven itself invaluable over the past 2 decades prior to the F-35s inception.
The F-117 Nighthawk flew over 1,300 missions over Iraq during the Gulf War, scoring direct
hits on over 1,600 high value targets, without losing a single aircraft. [19]
But it was far from perfect. Lockheed knew this all to well as the manufacturer of the
F-117. In 1999, a Nighthawk was infamously spotted by radar and subsequently shot down
over Serbia. The pilot survived, but the plane crashed and remained mostly intact. Handing
over a valuable technology to the Russians to reverse engineer. Stealth serves a single
purpose, to avoid detection, and the F-117 failed here.
But it was developed using 1970s era computing technology. It’s panels were flat and faceted,
simply because we did not have computers capable of analysing more complicated shapes to optimize
stealth.
Early attempts at stealth worked under a fairly simple theory. Radar works by sending out
pulses of electromagnetic waves, and waits and listens for reflections. The idea behind
stealth technology is to not reflect those waves back at the emitter, and thus avoiding
detection. This is why the F-117 is shaped like this. Each panel has been angled and
placed in a way to minimise how much of this energy it will reflect back to the sender.
It was also coated in a paint that would help absorb some of that electromagnetic radiation.
Opponents of stealth technology, despite its proven track record, are quick to point out
that long wavelength radar is capable of detecting stealth aircraft. The same kind of radar that
detected the F-117 over Serbia, and the same kind of radar used in the Battle of Britain.
While this is true, these stealth aircraft are optimized to avoid detection of higher
frequency radar. Those opponents rarely mention that low frequency, long wavelength radar
do not provide high fidelity measurements, and struggle to pinpoint the location of the
aircraft. [20] This makes them effective early warning systems, but entirely useless for
directing missiles. While this is certainly not useless, it’s not particularly useful
in air to air combat. Had the F-117 Nighthawk, on that night been escorted by it’s usual
squadron of electronic jamming prowler aircraft, the missiles may well have never got a lock.
[21] This made worse by the fact the aircraft was flying on a regular flight path and so
the Serbians knew where to look.
Topping this off, the F-117 was designed in an era before sophisticated computational
analysis was available, and so it took this relatively simplistic flat faceted form. The
B-2 however greatly improved on the technology, utilizing complex curved shapes which no human
could hope to calculate the radar signature of, and it has never been shot down. [3] The
curves diffuse those radio waves in many directions, rather than reflecting it all in one direction,
which makes it easier to detect by receivers listening in locations separate to the emitter.
A fairly standard practice today. The F-35 uses the same complex curves to avoid detection
by these high frequency radar, and this is likely one of the things driving it’s development
costs up the most.
Stealth technology requires precision beyond any other type of manufacturing. This is manageable
at small scale production, like that of the B-2 and F-22, which had very small production
runs. The F-35 is expected to be a mass manufactured aircraft, that foreign allies, with shallower
pockets than the US military, will be willing to pay for. Creating a manufacturing line
that requires this level of precision was never going to be cheap. Panels cannot have
gaps between them, they cannot be malformed. A single scratch on the radar absorbing coating
will require an entire repaint of the part. Small manufacturing defects have caused recalls
on multiple occasions. [need reference] Lockheed is only now starting to comfortably roll the
plane off the assembly lines, and that is reflected in the lowering the price of the
aircraft. The latest batch of orders had reduced in cost by 5.4% for the F-35A, 5.7 for the
B variant, and 11.1% for the F-35C.
Leaving us with a unit cost of 89.2 million for the F-35A, 115.5 million for the F-35B
and 107.7 million for the F-35C. With the F-35A expected to drop by a further 4.7 percent
to 85 million by the end of 2019.[22]
This sounds like a shitload of money to the average person like me, but we get a clearer
picture of these costs when comparing to other 5th generation fighters, like the F-22 Raptor,
which costs 150 million dollars per unit. Or even looking at the other aircraft it’s
going to be replacing. I think it’s fair to say that we have established that the F-35
is a worthy successor to all these planes, which individually come with their own hefty
price tags, but the F-35 manages to combine the capabilities of all these aircraft into
a single plane. [Slideshow of 4th generation planes and their associated costs]. Yes the
development costs of this plane has been astronomical. That cannot be denied, but much of that money
has gone directly back into the American economy. Then when you consider that the plane is expected
to sell up to 4600 units by the end of its lifetime [23], nearly identical to the total
f-16 sales figures. This will inject more money into the America economy considering
a large sum of these orders will be from international exports. So is the F-35 worth it’s 115.5
million price tag? As an Irish citizen that’s not for me to decide, but I can say one thing.
This is a fascinating plane with astounding capabilities.
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