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A fully loaded F-16 is a force to be reckoned with.
An air superiority machine that countries the world over use to patrol their skies.
A low cost, lightweight, single-engined fighter specifically designed to outmanoeuvre its opponents while carrying state of the art missiles that would, hopefully, mean it would never have to.
The F-16 was born out of the Vietnam War.
Large, heavy, complex US fighters like the F-4 Phantom were the norm, but the F-4 found itself in peril frequently.
At a significant disadvantage when taking on the smaller, manoeuvrable Soviet made MiGs of the Vietnamese Air Force, like the MiG-21.
The MiG-21 was a small, single-engined, lightweight aircraft with thin delta wings.
The F-4 was fast, flying up to Mach 2.2, travelled further, and carried more missiles, with a powerful radar, but it's lack of manoeuvrability at low speed, poor pilot visibility, and easy identification due to jet engines that billowed black smoke trails made it vulnerable to sneak attacks from the Soviet interceptor.
MiG-21s frequently flew close to the ground, under radar, and ambushed incoming F-4s, making a single attacking run with their ATOL infrared guided missiles, and then using their low speed manoeuvrability to outturn and escape.
From August 1967 to February 1968, US losses in Vietnam were staggering, losing 18 aircraft while downing just 5.
For a nation accustomed to absolute air superiority, something was off.
The MiG-21's introduction in 1966 forced the US to adapt.
It's large heavy fighter bombers, while useful, were at a disadvantage against the smaller, cheaper planes, and something needed to be done.
The Red Barn study, commissioned by the US military, began to identify and address the tactical and technical issues causing the heavy losses that both the US Navy and Air and their findings led to the development of one of the world's most ubiquitous fighter planes.
A plane designed with a new physics based doctrine at its core.
Entering service in 1978 and standing the test of time, it is now confirmed that the aircraft will be entering the battle for Ukraine's freedom.
Taking on the modern day counterparts of the MiG, this is the insane engineering of the F-16.
The F-16 was built from the ground up with this classified 1966 paper as its guiding light.
A paper full of mathematical models, graphs, and equations, designed to answer one question.
How to win a close quarters dogfight?
Created with the help of military supercomputers, it defined a new concept.
Energy Maneuverability.
Created by Colonel John Boyd, an Air Force veteran of the Vietnam War and one of the members of the so-called Fighter Mafia, with the help of a civilian mathematician, Thomas Christie.
These graphs were the basis for defining a plane's maneuverability through its full range of speeds.
Mach number on the X axis, turn rate on the Y.
A theory underlined by the management of both kinetic and potential energy, speed and altitude.
In order to change direction, a fighter aircraft must trade energy from these reservoirs, and doing it as efficiently as possible is the key to outmaneuvering an enemy.
This is the energy maneuverability diagram for the F-16.
It's a complicated graph to read without some basic understanding.
This line is defined by the maximum lift of the aircraft.
This is important, because it determines the maximum turn rate at a particular speed in this region.
We need lift to turn.
To begin a turn, an aircraft will roll in the direction of the turn.
This splits the lift the plane is generating into two components.
A horizontal component that causes the plane to turn, and a vertical component that keeps the plane in the sky.
A steeper bank angle will increase the horizontal component and increase our turn rate, while stealing lift from the vertical component.
This vertical component needs to equal the weight of the aircraft, or the plane will lose altitude.
To compensate for that, the pilot will need to increase lift by increasing the angle of attack.
This is where the maximum lift issue arises.
More lift means more available force to turn.
To determine the max turn rate for an F-16 at 0.4 mach, we simply draw a line straight up and across to our turn rate. 13 degrees per second.
Now this is where things get interesting.
This is the graph for an F-4E.
At the same speed, the F-4 can make a maximum turn of just 5 degrees per second.
To determine a sustained turn, we look to this line labelled with a zero.
Meaning no loss of altitude is required to make the turn.
We can see the F-16's best sustained turn is 14.2 degrees per second at 0.85 mach at 7g.
The F-4's best sustained turn is 10 degrees per second at 0.85 mach at 5g.
This is what that looks like in practice.
It takes the F-16 25 seconds to complete a full 360 degree turn, while it takes the F-4 36 seconds, 11 seconds in the difference.
The F-16 was a radical new way of thinking about fighter aircraft, and that design philosophy can be seen with how the engine inlet has been designed to deal with supersonic flow.
To learn more about the F-16, we spoke with an F-16 test pilot.
So the F-16 inlet is one of those things that tells you about the design philosophy of the aircraft.
Because up until that point, the thought process was we wanted to go faster, we wanted to go higher.
And nobody stopped to ask why.
Because it turns out that not a lot of fights, not a lot of air combat was happening in that mach 2 plus range.
In fact, very little of it was happening, and it didn't have a huge amount of tactical application.
And so as John Boyd and the rest of the team was looking at this lightweight fighter design, which became the F-16, they said, well, where do we think that the dogfights of the future are really going to happen?
And they said, well, it's probably going to be somewhere in that 0.8 mach to 1.2 mach regime.
That's really where we need to be in terms of optimizing the performance of the jet.
And we see that here in terms of the specific excess power chart where it's got this advantage right here in that range of 0.8 mach to 1.2 mach.
That's where the fat part of the chart sits.
That's where you're fat on energy.
That's where you have that advantage.
And so the F-16 propulsion system is not optimized to go over mach 2, although it can.
And I've flown the F-16 at mach 2.
You run out of gas pretty quick, but you can go that fast.
But in that, what we call transonic regime of 0.8 to 1.2 mach, you've got a different design problem than some of the previous jets.
And you can see that in terms of the inlets.
The inlets on the F-4 have this extension that goes sort of along the cheeks of the aircraft forward.
And then the actual inlet is, the inlets are set back.
And what that's designed to do is attach a shockwave to the front of that inlet lip.
And then it goes backwards and expands along the body.
And that shockwave is basically going to cover up the inlet.
That has some thermodynamic effects in terms of pressure recovery for the fan face, because you don't want supersonic air getting all the way in to your turbine.
If you have supersonic airflow hitting the front face of that jet engine, the jet engine is going to disintegrate.
It's designed to ingest subsonic airflow.
And so you have to attach that shockwave at the front of the airflow to eventually a normal shock inside the inlet.
It expands a little bit, and then it gets to the front face of the compressor, the fan face of the compressor.
Well, the F-16, and you can see it right here, has what we call a pitot inlet.
It's basically a flat face air scoop.
It is not that sort of overhang with a lip and then an inlet that's further back.
Like you see on the F-4 or the F-15 or the F-14, the big 29, the SU-27, all of those have more of that inlet that's set up to put an oblique shockwave across the front of the inlet.
Those are designed to go faster.
The F-16 has a little bit of that.
If you look at it on a side view, you can see how it's got a little bit of an overhang on the above Mach 1.2, and that's okay actually.
It can go that fast.
It can go faster, but the engine is working a little bit harder as it gets into this 1.4, 1.5 Mach range compared to something like an F-4 or an F-15.
That's where they start to really stretch their legs and run.
These designs for optimising manoeuvrability at these speeds can be seen elsewhere too.
It's air intake placement underneath the aircraft, a stark difference to the side mounted twin intakes of the F-4, and the thin elongated wing that blends smoothly into the fuselage with these wing extensions forward of the main wing.
These are called leading edge strakes.
This air intake ensured the F-16's engine was not starved of air during high angle of attack manoeuvres, with the forebody of the aircraft helping to funnel and divert air directly into the air intake.
However, this does come with some problems that needed to be engineered around.
On takeoff and landing, this air intake is only 100cm off the ground.
This combined with the extremely thin wings made placement of the landing gear difficult.
The forward landing gear could not be mounted ahead of the air intake, as it would kick up debris into it, and they couldn't fit into the wings either, as the thin aerodynamically optimised wing didn't have enough space.
The F-16's landing gears are stored just behind the air intake, and in order to provide enough stability and bracing on landing, they need a unique folding mechanism to swing them outward to create as large a wheelbase as possible.
The front landing gear, which is steerable during taxi, also rotates 90 degrees to lie flat just under the engine inlet.
Above the inlet is a boundary layer diverter channel.
This ensures the engine gets consistent laminar flow.
As air travels along the length of the aircraft it forms a layer of slow moving turbulent air called a boundary layer.
If this air is allowed to enter the engine, it not only lowers performance, it can also damage the engine.
As the turbine rotates it will pass through the slow boundary air on one side, and then the fast free stream air on the other.
This means the force on the turbine blades changes for each and every rotation, causing cyclical bending, a recipe for fatigue failure.
This boundary layer diverter separates this layer and diverts it underneath the wings.
All of this ensures the engine can operate as high a thrust as possible, even when the F-16 is performing extreme manoeuvres, which is exactly when it is needed most as the plane bleeds energy to produce lift.
It's essential that a plane like this can continue to generate effective lift during these manoeuvres.
But, typical wings lose lift as angle of attack increases beyond a certain angle, as flow separates from the wing.
This is called a stall.
These leading edge strakes help to mitigate that.
They act similarly to the canards of the Su-34, one of the planes the F-16 will likely be going up against in Ukraine, with 19 of them reportedly being taken down thus far in the war.
Canards and leading edge strakes help produce lift during high angle of attack manoeuvres.
Canards placed close to the wing, like the Saab 37 Viggen, create a vortex that passes over the wing.
Ensuring the wing continues to get high energy airflow during high angle of attack manoeuvres, which allows it to continue generating lift.
During the development of the F-16, General Dynamics did consider a canard configuration, testing different configurations and geometries, including versions with no strakes or canards, with subscale models in wind tunnels.
Testing through it's optimum manoeuvring speeds between 0.4 and 0.8 mach.
The goal was to maximise lift and minimise drag at high angles of attack.
Producing graphs like this, and these were used to compare designs.
As they were narrowing down on the design, they consulted NASA, and they found one area to improve on.
The sharpness of the leading edge.
General Dynamics had rounded the leading edge of the wing to weaken these high angle of attack vortices, but NASA advised them to sharpen the leading edge in order to strengthen them.
The F-16 underwent a great deal of iterative design in the wind tunnel phase, before eventually landing on the design we are familiar with today.
With the long blended leading edge strake that makes the F-16 immediately recognisable, and this comes with an added benefit.
It provides enough space for the barrel of the F-16's powerful 20mm rotary cannon.
You can see the barrel of the M61 Vulcan hiding here.
A minor clue to the weapon hidden within the fuselage of the tiny plane.
One of the early conclusions of the Red Baron report was that the lacklustre ornament of the F-4 made it difficult for it to compete in close quarter battles.
It lacked an internal cannon, which left the F-4 without offensive options in close quarter battles, where missiles could not be safely used.
The F-4 was eventually retrofitted with the M61 slung underneath the plane, but the F-16, looking to fix the problems of the past, came with the General Dynamics M61 Vulcan Rotary Gatling Gun as standard, and it was packed neatly inside the plane, creating minimal aerodynamic drag.
The M61 is the smaller cousin of the A-10's GAU-8A, and while its rounds are tiny in comparison, the noise it emits still packs a punch.
A massive cannon for a tiny aircraft.
The 6 barrel cannon fires from the top position, spinning 16 times per second.
The Gatling rounds, the full ammunition drum can be unloaded in just over 5 seconds.
The drum fits neatly behind the pilot here, and the vibration of the gun firing on the pilots left side is jarring for many new pilots.
It is such a small fighter.
You know, when you, and I think I've said this before, when you get into an F-16, you sit down and you strap into that, it's not like you're sitting in the jet, it's like you're wearing the jet, and the gun is right here.
As I sit there in the cockpit, the gun barrels, the muzzles are right back here.
It's just out of reach, it's so close though, and so when you shoot the gun, and you're shooting 100 rounds a second of 20mm, it is unbelievably violent in the jet, but you're thinking about the that you have to go and shoot.
And so, you know, one of my experiences flying the F-16 was I was teaching as an instructor pilot at Luke Air Force Base in Phoenix, Arizona.
And so I had the privilege of taking in Air Force pilots, they're wearing wings, they've graduated Air Force pilot training, but they're not fighter pilots yet, and putting them into an F-16, and then we would make sure that everybody shot the gun in training, in fact they had to qualify with the gun as a weapon.
And so the first time experience for anybody shooting the gun in an F-16 is a little bit of an emotional experience.
People would say funny things, they would cuss, it was all on the tapes, the HUD tapes, the heads-up display recordings, and we'd come back in the debrief and kind of laugh at the students because they were just, they knew that they were going to go shoot the gun, and it was not always shooting at a target on the ground is when they would do this for the first time.
Strafe.
And so it's a little bit intense, you're diving at the ground, you're doing 450, 500 knots, pointed at the ground, obviously there's a survival instinct that kicks in there, you're trying to put the pipper on the target, you pull the trigger for the first time, and the whole jet shakes violently.
It's like somebody started up a chainsaw just in your left ear.
And the whole jet is shaking, and your hand's on the throttle there, and I can always remember every time I would shoot the gun, there's this hard foam insulation that's just behind the closeout panel, but the vibrations would cause some of those little bits of foam to fleck off, to flake off, and they would come around the closeout panel, and every time I would go shoot the gun for practice, for strafe, I'd come back and as I'm getting out of the airplane, I'd see like these little yellow flecks of foam all over my green flight suit on my left arm, they would just, the vibrations were so intense, you get used to it after the first time you shoot it, it's a little bit of an emotional event, and after that you're focused on, I need to put those rounds on target.
So the F-16 is incredibly well integrated as far as a weapons system with that gun, and I will tell you that both for air-to-ground, and also for air-to-air, the and even with dynamics on the aircraft, even under maneuvers in terms of air-to-air shoots, where we're shooting at a banner, there's not been a lot of actual air-to-air dogfighting with the gun in recent memory, but the F-16 is incredibly accurate when it shoots at air-to-air practice targets to the point of, it's almost not even fair, it used to be kind of a scoring, kind of a skill thing, and now you can just park the piper on the target, open up, and it just shreds anything you point it at in terms of an air-to-air target.
And then in terms of air-to-ground, you can be extremely precise with it, it's not quite a laser beam, but you can be extremely precise, and there's even ways that you can couple up other sensors on the aircraft and share information, even in an at night, blacked out type of close air support role, you can hit what you want to hit on the ground.
All from a gun hidden away inside the tiny fighter.
If we follow this leading edge strake down the wing, we come to another device designed to increase lift at high angles of attack, the leading edge flap.
It deflects downwards during high angle of attack manoeuvres to delay stall, allowing air to remain attached to the wing surface.
When performing a sustained turn at 0.9 mach at cruising altitude, it increases lift by 18% and decreases drag by 22%.
You can see them actuate here during the 5G take-off I performed with the Thunderbirds back in 2019.
The seam between the leading edge flap and the main wing is barely noticeable, and fitting a control system into this wing, which is only around 4 centimetres thick where the actuator system needed to fit, proved a challenge.
The amount of torque needed to actuate a control surface like this at 0.9 mach is not trivial.
To solve this problem, power is transferred from two hydraulic motors, which convert the pressure in the hydraulic system into rotational motion.
The hydraulic drive motor itself is tucked away behind the M61 rotary cannon, next to the hydraulic motor that drives the cannons rotation and ammo drive system.
This power has to be transferred to the wing, and this is done through a series of torque shafts, angular gearboxes, and down another series of torque shafts with rotary actuators in between.
This leading edge flap is not controlled by the pilot however, it's controlled automatically by the flight computer, and the F-16 was groundbreaking in this regard.
The F-16 was the first fighter aircraft to have a fly-by-wire system controlling every control surface.
The leading edge flaps, the flaperons, the rudder, and the horizontal tail of the F-16 are not controlled directly by the pilot.
A fly-by-wire system uses a network of sensors, wires, and computers, as well as the pilot's own input to control the plane.
The F-16 was employing this new technological wizardry to allow it to efficiently spend the energy it's single jet engine provided.
Traditional flight control systems up to this point used a mechanical system connected directly to the pilot's controls to manipulate the flight surfaces.
This is footage of the F-4's control system.
A heavy and complicated network of cables, rods, linkages, and hydraulics.
It even has a 2 kilogram bob weight attached to the pilot's stick.
A mechanism designed to make it harder to pull the stick as G's increase.
An analogue feedback system.
To provide the pilot with analogue feedback on speed, the F-4 also featured a diaphragm that deflected with ram air taken from this probe on the vertical fin.
This introduced a force that acted to push the stick backwards and indicated to the pilot to adjust a trim setting.
This system not only added a huge amount of weight to the F-4, reducing it's manoeuvrability, it also added workload to the pilot and was more vulnerable to damage in dogfights with little redundancy.
With a fly-by-wire system, none of this was needed.
The first batch of F-16's actually a stick that was immovable.
It was just for sensing.
Later, a small amount of movement was added after pilots complained.
So the non-movable stick, kind of a little known fact, you know the original F-16 wasn't a Lockheed Martin product, it was General Dynamics, and they had made the F-111 previously and the weapon system operator on the F-111 had a small joystick that they could use to movement.
It wasn't really a joystick that would move, it was just to apply force.
And so they took that same concept and then they put it into the F-16 stick.
So it was sort of a General Dynamics thing of we've got a force transducer, a control inceptor is what you'd call that.
So what it turns out though is that the human body does really well with knowing where your limbs, hands are moving.
Knowing the position of your body is something that you naturally do pretty well and that is something called proprioceptive feedback.
Well when I have a force-based inceptor, I don't get that proprioceptive feedback anymore.
And it's really hard to judge.
It's something that I think if you challenge yourself to go pick up a small weight at the gym and ask yourself how much does that weigh without looking at it, it's actually kind of hard to guess when you're down in those few pounds range and the maximum force you can put on the F-16 side stick is 25 pounds.
So it's kind of hard to tell the difference between 15 pounds and 15.2 pounds.
We don't do very well with that.
We do a lot better with knowing how far we've pulled something.
And so the thing that we found was that they were having a difficult time, the test pilots at Edwards were having a difficult time judging exactly how hard they would move the controls and so they would think they were going to get a certain response from the jet and then they weren't and then they pull harder, too hard, and then they get a different response.
There is a phenomenon called pilot-induced oscillations or pilot-in-the-loop oscillations.
Sometimes it's just shortened to PIO.
And the F-16, even to this day, particularly if you have a lot of wing stores, can have a little bit of a wing rock on landing.
And if you look at some videos of F-16s landing, sometimes you can find if they have wing tanks or they're bringing back some bombs that they didn't expend, you'll find an F-16 that'll sort of do this little back and forth wing rock.
And that is still to this day, it's an artifact of having a side stick that doesn't move very much because it's one of those things that in terms of the mind to the hand, eye-hand coordination, you start to make a movement.
By the time you see the effect, it's more than you wanted.
So you take it out, you put in a correction.
By the time the correction takes effect, it's more than you wanted.
You see it, you come back.
It's a feedback loop in our minds.
And now PIO is kind of a dirty word in aircraft design and nobody wants any PIOs.
I'll tell you PIOs, pilot-induced oscillations are like snakes and some snakes are very dangerous and some snakes are not.
And so the PIO that's remaining in the F-16 in terms of its wing rock on final at landing is not super dangerous.
These pilot-induced oscillations can also be naturally stabilized through passive stability, where the plane naturally self-corrects itself without pilot input.
However, the F-16 was the first aircraft in history to do away with passive stability and make the plane intentionally unstable in flight.
This was done because it lowers the energy needed to fly and maneuver.
We can understand why with this simple analogy.
Here we have two situations, a ball placed on top of a hill and a ball placed in a valley.
If we push the ball on top of the hill even a tiny bit, it will begin to accelerate down the hill and will not stop until we put energy in to slow it down.
This is an unstable system.
The opposite is true for the ball in the valley.
Apply a force and the ball will roll uphill and gravity will now provide a restoring force to bring it back.
It may oscillate back and forth a few times before coming to a stop, but it will eventually return to its original position.
This is a stable system.
We want to tailor our stability to find a balance between these two scenarios, where we can cause a rapid change in direction with a small energy input, while also managing the amount of energy required to get back to our original position.
This is called Relaxed Static Stability.
The F-16's pitch stability is one of the areas where this idea was applied.
One of the key factors that affects pitch stability is the location of the centre of gravity and centre of lift.
The centre of gravity for the F-4 is located about here.
This is the point at which all lift will act around.
It's like the fulcrum on a seesaw.
As a result of the wing design, the centre of lift is slightly behind the centre of gravity.
This would force the plane to pitch downwards, but the horizontal stabilizer provides a counteracting downwards force.
This isn't ideal.
We are wasting energy on downwards lift.
We need upwards lift to fly.
It also increases the amount of energy the F-4 needs to input to change its pitch.
When it pitches upwards, the force on the horizontal stabilizer decreases because of reduced airflow, and as a result the weight of the plane, acting through the centre of gravity, forward of the centre of lift, wants to move the nose down again.
But the pilot is trying to pitch the plane up, and this natural stability is fighting them.
So, more kinetic energy has to be wasted by converting it to lift and drag with an increased elevator deflection.
The F-16 is different.
Its centre of lift is ahead of its centre of gravity, in part thanks to those leading edge strakes pushing the centre of lift forward.
This means to balance the plane, the horizontal stabilizer needs to create upwards lift.
This is useful the energy needed to keep the plane airborne, and increases our maximum lift, pushing this line on our energy manoeuvrability diagram up, increasing our turn rate.
However, it's an unstable system.
When the plane pitches up, it increases the angle of attack on the wing and increases the lift.
Because the centre of lift is ahead of the centre of gravity, this forces the nose up even more.
In an air to air battle, energy isn't just a fuel burning problem.
Energy is needed to manoeuvre, and as we spend it, our ability to manoeuvre diminishes until we replenish it by gaining speed or altitude again.
Any fighter pilot will tell you, speed is life.
And as a fighter pilot, energy management is one of the most important things that you can do.
It's part of your situational awareness in that combat arena.
You don't want to get slow, and you don't want to put yourself in a place where you are vulnerable, and now I can't turn, I can't move, I can't get my sensors or my weapons engaged where I need to.
And that's not just an air to air thing.
That's in every aspect of being a fighter pilot.
And that's even engaging in an air to ground arena, because often times when you're engaging air to ground, an interdiction mission, a strike mission, or a close air support mission, well, you're supporting friendly troops on the ground, but there's also people that really don't like you in the vicinity, and they have weapons also.
And so, you have to maintain that energy to be able to evade, to be able to move out of the way if you're getting shot at.
So, with the energy management on the F-16, it's interesting that this jet doesn't really talk to you in terms of feedback to the pilot.
It doesn't really shake and rattle and vibrate like a lot of other aircraft will do.
I've flown the F-16, I've also flown the F-15, the F-18, the A-10, and those aircraft will talk to you, those other aircraft will talk to you a lot more than the F-16.
The F-16 just feels smooth all the time, whether you're 200 knots and really slow, or you're 600 knots and really fast.
It just sort of does what you ask it to do.
You think, you move the controls just a tiny bit, and the aircraft responds.
So, managing your energy becomes a situational awareness challenge for the fighter pilot.
And so, a lot of that's helped now with the Joint Helmet Mounted Cueing System, or JEHEMIX is what it's called, where right there in your right eye, you've got your airspeed, you've got your altitude, you've got your G, and so you can engage visually in that fight.
I can keep my eyes on the threat, the target, keep situational awareness, and I don't have to look back in at my heads-up display or down at the console to see how fast I'm going and how high I'm going.
You get the feel for it, you get a feel for how the aircraft is responding, but that's where experience comes in, and it's imperative.
Experience and training comes in.
It's imperative to maintain that energy awareness in any kind of fight.
The unstable design of the F-16 helped fighter pilots like David to manage energy more efficiently.
But, to maintain control of an unstable fighter, a pilot would have to make constant, tiny corrections.
A task deemed impossible before fly-by-wire systems were invented.
The system consists of a network of accelerometers, gyros, and airspeed sensors, all feeding into a central computer that manages the work.
This instability makes the plane extremely nimble, ready to change direction, with very little energy input.
We could see this in practice on the first flight of the F-16 prototype, the YF-16.
A flight that was never supposed to happen.
This was intended to be a short test along the runway, but the early control logic of the plane would not allow the engine nozzle to open to cut thrust if the wheels had left the ground.
Meaning, even at idle the plane was generating too much thrust.
Then the plane rolled left, which caused the pilot to counteract it with a roll right command.
But again, the control logic of the early prototype was not dialed in, with control input resulting in higher roll than expected at such a low speed, resulting in an overcorrection, leading to an oscillation.
With this being the first full fly-by-wire plane, there were many lessons to be learned along the way.
But the benefits it now provides are game changing.
It helps the pilot get the most out of the plane.
So, for example, with an F-16, the airframe is limited to 9Gs.
And so I can go and pull back on the controls on an F-16, and if I am less than about 300 knots or so, actually more like 400 knots, I'm not going to get 9Gs.
It's just, that's how much lift the aircraft can make.
But once I get above about 400 to 450 knots, now the wing on the F-16 is capable of creating at least 9Gs.
In fact, it's capable of creating a lot more than 9Gs.
But what that fly-by-wire system does, is when I start pulling back all the way to the stop, it goes to 9Gs and it sits there.
Even if the wing, even if the aerodynamic effect of the whole airframe is that it could generate 15Gs or 20Gs, the fly-by-wire system says, hey, I know you're asking for your best possible turn, I'm just going to give you 9Gs because we're not going to break the airplane.
Or, again, in like a slow speed fight, where I'm having to, it's less than 300 knots, I'm having to crank the nose around to either bring my adversary, or maybe I'm trying to jink out of the way of an adversary's weapon system.
Pull suddenly on the controls of an aircraft and your angle of attack is going to increase rapidly.
All right, well, with a lot of more conventional aircraft, you're worried about things like stall.
Well, the F-16 doesn't really stall in the same kinds of ways, but that fly-by-wire system says, hey, I know that if you get past about 26 degrees angle of attack, bad things are going to start to happen in terms of the controllability.
The F-16 stops behaving as predictably above 26 degrees angle of attack, and so the fly-by-wire system simply says, that's where I'm going to stop you right there, and I'm going to give you up to 26 degrees, or 9Gs, and do with that whatever you need to.
A plane capable of 9G manoeuvres is not much use if the pilot cannot remain conscious during them.
The F-16 has some interesting adaptions in the cockpit for this.
Traditionally the control stick was mounted centrally, between the pilots legs.
This made it mechanically simpler, with the network of mechanical linkages being central and symmetric throughout the plane.
It also allowed the pilots to use both hands to wrestle the control surfaces into position during high G manoeuvres, as the air flowing by them tried to push them back down.
For the F-16 this wasn't a problem, and the control stick was mounted conveniently on the pilots right hand console.
A comfortable resting position that makes it far easier for the pilot to control the plane while trying to stay conscious at 9Gs.
The seat is also reclined by 30 degrees.
This makes the F-16 feel like an executive office in the sky, with unobstructed 360 degree views thanks to the bubble canopy.
But it also comes with major advantages in increasing the pilots G tolerance.
The most common G-force a pilot experiences is directly down.
When flying in a straight line, even cells in your body have inertia in that direction, and when suddenly pitching the plane upwards, those cells want to continue travelling in that direction.
This isn't too much of a problem for cells that stay fixed, but your blood cells are free to travel through your body.
And in a scenario like this, they race in the direction of that travel, pooling in your lower extremities.
This can starve the pilots brain of oxygen and they can pass out as a result.
This effect can be minimized by placing the pilot flat on their back.
With the entire body aligned, blood wouldn't have to fight gravity to get to the brain, but this position isn't practical.
The F-16 found a compromise with a 30 degree recline, reducing the pressure on the heart by an equivalent of about 1G.
The recline also makes it easier to fit taller pilots into the small forward fuselage of the F-16.
Another measure to increase the pilots G tolerance is the G-suit.
A pilot's G-suit contains multiple air bladders that are connected directly to the F-16.
When the plane is instructed to perform a high G manoeuvre, it immediately begins to pump compressed air into these bladders.
This squeezes the pilots legs to limit the volume available for blood to pool into.
The F-16 is a 45 year old aircraft and many advances have occurred in aviation since its maiden flight.
Stealth technology and interconnected intelligence networks have been the main focus for 5th generation aircraft like the F-35, that have been slowly replacing the F-16.
But, one thing has not changed since 1975.
Physics.
The F-16 pushes the boundaries of manoeuvrability for a fighter aircraft and the pilot inside.
It's a highly capable fighter aircraft that the strongest air force in the world deemed capable of continuing service until 2048.
The plane will be a major asset in the next phase of the fight for Ukraine's freedom, providing essential air support to the troops on the ground as they attempt to push forward through entrenched Russian defences.
Ukraine has been targeting long range anti-aircraft batteries with success, and captured oil platforms off the coast of Crimea that were housing Russian sensors.
All to clear the way for Ukrainian Su-24s to get close enough to launch cruise missiles.
Targeting high value Russian assets in Crimea, including a Kilo-class submarine.
The F-16 can also carry these cruise missiles.
Every asset in the Ukrainian air force is going to play a vital role in Ukraine's fight for freedom.
Having an actual fighter pilot add context to this story was incredibly valuable.
Helping us truly understand the power of those energy manoeuvrability diagrams.
We ended up talking to David for nearly two hours, and ended up cutting an incredibly interesting story from this video about how he helped develop an automatic obstacle avoidance system for the F-16 that has saved many lives.
A fascinating system that works in a way I didn't expect.
I had assumed it simply used radar to measure distance, but that is not how it works.
You can watch that extra video on Nebula right now, along with an uncut explanation of energy manoeuvrability diagrams.
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Something I find really valuable while watching long form videos.
When I am taking flights to shoot interviews, I often download videos from Nebula, which you can do by the way, and watch them on the flight.
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