What is the best aerodynamic configuration for a fighter aircraft?

[Justo Miranda]

Even if all aircraft are unmanned and flown by AIs, you're still going to have aircraft whose job is to stop the enemy UCAVs from doing their job.

That's a fighter.

In my opinion, the type of weapon you describe could be defined as a reusable missile.

The machines do not fight or hunt, that is a human characteristic with the epic and the added nobility of the one who defends his cities and non-belligerent population.

 

[Justo Miranda]

Did you perhaps mean Spitfires against the V-1, rather than the V-2?

F-106 against FOBS

Fractional Orbital Bombardment System - Wikipedia

en.wikipedia.org

 

[Justo Miranda]

ballistic missiles are good against static targets with known location. Against moving and pop up target, you still need something to find and target them. A ground based system like a tank is limited by line of sight, so they can't detect and lock target from long range. Moreover, they also move very slow. So you still need an airborne reconnaissance at the very least.
Sure you can use airborne reconnaissance and surface to surface ballistic missile to attack. But then it would be quite expensive because ballistic missiles are single use weapon, and big ballistic missiles that can have the range equal to combat radius of fighter are also very expensive. It not suited for sustain conflict. So you need something that can drop glider bomb. Which is a lot cheaper.
But if we have bombers then there must be something to intercept/stop them. Sure you can use SAMs, but the problem with SAMs is also similar to the problem with a tank. They are limited significantly by the radar horizon, and they can't move around quickly, so the enemy can find a hole in your defend and pull all their bomber/strike aircraft through that hole. That mean you need an interceptor/fighters.
Drones are very cheap but they also has their own weakness, for example: they will be quite vulnerable to jamming, and until we can put a good AI that can replace human, they your anti air drone will rely on off board control, which will also affected by latency.



Drones are very cheap but they also has their own weakness, for example: they will be quite vulnerable to jamming, and until we can put a good AI that can replace human, they your anti air drone will rely on off board control, which will also affected by latency.


After the pager attack, Hezbollah leadership decided to have meeting face to face. F-15 were used to drop bunker penetrating bomb to get rid of them all. You will need a massive drone to be able to carry GBU-28

That's true, but it's a new technology with huge potential for development, while resistance to the pilots' g-forces is constant.

 

[Arjen]

J-35 Drakken

I am beginning to think I am flogging a dead horse, as it is a common mistake.

It is Draken, with one K
Have mercy.

 

[Justo Miranda]

I am beginning to think I am flogging a dead horse, as it is a common mistake.

It is Draken, with one K
Have mercy.

Draken-Drakkar

Draken Harald Hårfagre

The World´s largest Viking Ship Sailing in modern times.

www.drakenhh.com

Drakkar, The Longship Of The Vikings

The Vikingsâ longships did follow the guidelines of general shipbuilding shape of being long and narrow. Their general term was langskip (longship) and were opposed to the wider merchant ships called Knarr or Kaupskip, often maintaining a 7:1 length/wide ratio.

northlord.com

 

[F-14ATomcat]

I am beginning to think I am flogging a dead horse, as it is a common mistake.

It is Draken, with one K
Have mercy.

Thanks

Well the Draken or Dragon have a very nice wing very modern for a very old aircraft

see

F-16XL


The J-35 had basicsally the same wing the F-16XL had with the exception of the notch on the wing root



Basically it was not the same wing but it gave way to very modern designs




Basically was one of the first compound wing designs and nowadays this type of wing is very popular

 

[Justo Miranda]

Thanks

Well the Draken or Dragon have a very nice wing very modern for a very old aircraft

see

F-16XL

View attachment 758880
The J-35 had basicsally the same wing the F-16XL had with the exception of the notch on the wing root
View attachment 758881
View attachment 758882

Basically it was not the same wing but it gave way to very modern designs

View attachment 758884


Basically was one of the first compound wing designs and nowadays this type of wing is very popular

Henschel P.135 http://www.luft46.com/henschel/hsp135.html

 

[red admiral]

The J-35 had basicsally the same wing the F-16XL had with the exception of the notch on the wing root

Superficially looking similar is not the same as "basically the same". The flow physics is significantly impacted by multiple other features e.g. leading edge sharpness, LE crank location, TE crank location, fences, LE devices etc.

The wings are very very different with different performance

 

[Ronny]

I vaguely remember that F-16XL wing is good for supercruise since the supersonic drag is pretty low. However, the lift generation at low AoA isn’t as good as a more straight wing, so F-16XL str is actually worse than F-16C

 

[F-14ATomcat]

Superficially looking similar is not the same as "basically the same". The flow physics is significantly impacted by multiple other features e.g. leading edge sharpness, LE crank location, TE crank location, fences, LE devices etc.

The wings are very very different with different performance

of course they are different, but they have also similarities too.

The J-35 has a compound delta like F-16XL and it seems Su-75 will have the same basic concept, not the same wing.

Compound deltas were designed to fix the low speed faults of delta wings, specially tailess delta wings.

Modern fighters want dymond type wings, but they want increased area, some designs are going for tailess wings and Draken already had the same needs a tailess delta, well compound delta wings.

So there is a convergence in needs a tailess wing, is good for stealth and low drag, but it is bad for controllability.

 

[Foo Fighter]

Manned or unmanned, there will always be aerodynamic limitations. The airframe also contributes to this rather than just the squidgy organic componant.

 

[Byeman]

The time has come for robots, faster than any top gun, cheap, disposable and so small that neither the fighter radar nor the pilot will know that they are nearby. Drones can attack by the hundreds, suicide attacks, and small ones can infiltrate any air base to destroy everything by entering the air intakes and detonating small charges. The drones of the future will not need to refuel, they will use electric motors, solar energy and advanced batteries.

they don't have the range

 

[WarValor]

Depends.

 

[F-14ATomcat]

they don't have the range

The size of an aircraft is related to the payload it carriers, and this is directly affects the fuel needed to be carried depending in the efficiency of the powering sources and engine.


Drones have the advantage a pilot is not needed, thus this reduces the size at least of the cockpit (avionics carried) and no need for a human means no space for a living organism.


You can make a drone as fast as a manned aircraft and with the same range of a manned aircraft.

Electric drones use at this moment propellers, so they have relatively speed limitations and range limitations, future technology might change all that

 

[Scott Kenny]

Electric drones use at this moment propellers, so they have relatively speed limitations and range limitations, future technology might change all that

Not even current scientific papers (yet to be duplicated) support battery improvements of the required orders of magnitude increases in energy density.

 

[Ronny]

of course they are different, but they have also similarities too.

The J-35 has a compound delta like F-16XL and it seems Su-75 will have the same basic concept, not the same wing.

Compound deltas were designed to fix the low speed faults of delta wings, specially tailess delta wings.

Modern fighters want dymond type wings, but they want increased area, some designs are going for tailess wings and Draken already had the same needs a tailess delta, well compound delta wings.

So there is a convergence in needs a tailess wing, is good for stealth and low drag, but it is bad for controllability.

it seem like due to the creation of HOBS missile and TVC, the need for low speed STR is eliminated, so swing wing and straight wing become redundance. Most fighter seem to emphasize high speed capability

 

[Scott Kenny]

it seem like due to the creation of HOBS missile and TVC, the need for low speed STR is eliminated, so swing wing and straight wing become redundance. Most fighter seem to emphasize high speed capability

Redundant for maneuverability, sure, but not redundant for landing characteristics.

I still expect the LockMart FAXX proposal to have swing wings. Crud, the NG version might, too, but their F-23N proposal was canard instead of swing-wing.

 

[Justo Miranda]

The size of an aircraft is related to the payload it carriers, and this is directly affects the fuel needed to be carried depending in the efficiency of the powering sources and engine.


Drones have the advantage a pilot is not needed, thus this reduces the size at least of the cockpit (avionics carried) and no need for a human means no space for a living organism.


You can make a drone as fast as a manned aircraft and with the same range of a manned aircraft.

Electric drones use at this moment propellers, so they have relatively speed limitations and range limitations, future technology might change all that

In my opinion, the future of drones will not be about competing in range and speed with fighters and missiles. They are cheap, can operate in large numbers, suffer many casualties and fulfill their mission if some manage to overcome the defenses. In theory, their range can be unlimited if they stop charging the batteries with solar energy and that allows them to have any size. They do not need to carry bulky warheads if they can be introduced inside the ventilation systems of enemy machines, a toxin, a small acid deposit or a thermite charge will suffice.

 

[Ronny]

In my opinion, the future of drones will not be about competing in range and speed with fighters and missiles. They are cheap, can operate in large numbers, suffer many casualties and fulfill their mission if some manage to overcome the defenses. In theory, their range can be unlimited if they stop charging the batteries with solar energy and that allows them to have any size. They do not need to carry bulky warheads if they can be introduced inside the ventilation systems of enemy machines, a toxin, a small acid deposit or a thermite charge will suffice.

Small Drone probably super vulnerable to EMP though

 

[Michel Van]

I think that aerodynamic of Fighter Jet is definite by it's purpose

A interceptor must get fast to target and destroy with missile
If you need Dogfighter it will have completed different aerodynamic as Interceptor
and is a Multi combat aircraft has also different characterisation as two others

Variable swept wing are out, do its high maintenance cost. (see end of F-14)

I believe the cranked arrow Delta wing of planes like F-16XL and Canard delta will be dominant in future Fighter designs

 

[Justo Miranda]

Small Drone probably super vulnerable to EMP though

That is true, but in order to use EMP defenses it would be necessary to protect against EMP all facilities that can be attacked by drones, practical results in exchange for endless economic battle. I'm serious when I propose the use of trained birds of prey, but they'll only be useful against small drones and will only act during the day. Against the big drones the best is the old ZSU but against the small ones at night... I can't think of anything, maybe a millimeter radar, I don't know.

 

[F-14ATomcat]

it seem like due to the creation of HOBS missile and TVC, the need for low speed STR is eliminated, so swing wing and straight wing become redundance. Most fighter seem to emphasize high speed capability

by fighter people understand a machine that can fight other aircraft at any range and with several types of weapons.

F-14 was that type of aircraft, MiG-29 too.

However the modern trend is for aircraft that fight far off the WVR and avoid almost any combat with the enemy at short distances.

Basically the modern aircraft is an interceptor, or even worse a F-111 type aircraft or Su-34.

Maneuverability has gone as the main requirement and instead speed (interceptor) has become the norm.

Take the Su-57 without TVC nozzles and those tiny vertical stabilizers will show it how clumsy it is, same F-22.

Add AIM-9B and no helmet mounted sights and F-35 will become a modern F-105.

The aerodynamic control has become minimalist, this has made aircraft with poor agility.

Su-27M had many aerodynamic control surfaces, even without TVC nozzles could outmaneuvered even most 1990s fighters.

That is the modern trend, basically a heavy attack aircraft with little agility and speeds in the range of Mach 1.6

 

[F-14ATomcat]

In my opinion, the future of drones will not be about competing in range and speed with fighters and missiles. They are cheap, can operate in large numbers, suffer many casualties and fulfill their mission if some manage to overcome the defenses. In theory, their range can be unlimited if they stop charging the batteries with solar energy and that allows them to have any size. They do not need to carry bulky warheads if they can be introduced inside the ventilation systems of enemy machines, a toxin, a small acid deposit or a thermite charge will suffice.

Drones can be hacked drones need a human to give them orders, so the 6th generation aircraft it is supposedly stealthy machines (the reality nothing is stealth because aircraft are made of many materials and any electromagnetic wave will generate heat, electric currents, emissions, reflections, refraction, and energy never disappears), it simply is either made mass or remain energy and as energy electromagnetic waves are emitted as quanta, basically as radiation.


There are in my opinion two weapons that will change warfare, biological weapons and high energy weapons that down ICBMs, The drone will not change warfare, the drone will only make harder war

 

[Michel Van]

Small Drone probably super vulnerable to EMP though

it get worst for coming new generation of fighters Aircraft
with there High complex computers that communicate with it's Drones, other aircraft, missiles, the Battle field and HQ.

EMP is not such a problem, if aircraft electronic is radiation harden.
but the vital communication can be disrupted, even hacked !
We see the begin of those tactic and this technology emerging during Ukraine-Russia War.

 

[Justo Miranda]

Drones can be hacked drones need a human to give them orders, so the 6th generation aircraft it is supposedly stealthy machines (the reality nothing is stealth because aircraft are made of many materials and any electromagnetic wave will generate heat, electric currents, emissions, reflections, refraction, and energy never disappears), it simply is either made mass or remain energy and as energy electromagnetic waves are emitted as quanta, basically as radiation.


There are in my opinion two weapons that will change warfare, biological weapons and high energy weapons that down ICBMs, The drone will not change warfare, the drone will only make harder war

The drones I was referring to are supposed to make their own decisions without any human control or emit any radiation, except for a minimum of IR... shoot and forget. I think that all the tactical experience of each surviving generation of drones could be recorded in them so that they learn to hide and act in moments of minimal surveillance.

High-energy weapons can only act up to the level of the visible horizon, they are good for defense, but not for attack unless they can be miniaturized enough to be fired from aircraft or satellites.

 

[Ronny]

it get worst for coming new generation of fighters Aircraft
with there High complex computers that communicate with it's Drones, other aircraft, missiles, the Battle field and HQ.

EMP is not such a problem, if aircraft electronic is radiation harden.

It is easier to harder a big aircraft than a small drone I think

 

[Scott Kenny]

I think that aerodynamic of Fighter Jet is definite by it's purpose

A interceptor must get fast to target and destroy with missile
If you need Dogfighter it will have completed different aerodynamic as Interceptor
and is a Multi combat aircraft has also different characterisation as two others

Variable swept wing are out, do its high maintenance cost. (see end of F-14)

I believe the cranked arrow Delta wing of planes like F-16XL and Canard delta will be dominant in future Fighter designs

I'm leaning more towards either 3-surface or canards than cranked deltas.

 

[Michel Van]

I'm leaning more towards either 3-surface or canards than cranked deltas

like i said the aerodynamic and wing form depends what aircraft purpose is
canards are ideal for dog fight like Rafale
cranked deltas ideal for multi combat aircraft like F-16XL

It is easier to harder a big aircraft than a small drone I think

that not problem per se
its amount of complex Communication they want for coordinate combat.
not only between Fighter and it drones, but also wingman, the entire squadron.
also communication with ground forces and real time update on combat situation
in US the B-21 will serve not only as bomber, but also as communication hub/server for this

the real danger here is Lost of Communication or worst false information given by enemy
this is the Achilles Heel for new generation of Fighter Jet in development...

 

[F-14ATomcat]

like i said the aerodynamic and wing form depends what aircraft purpose is
canards are ideal for dog fight like Rafale
cranked deltas ideal for multi combat aircraft like F-16XL


that not problem per se
its amount of complex Communication they want for coordinate combat.
not only between Fighter and it drones, but also wingman, the entire squadron.
also communication with ground forces and real time update on combat situation
in US the B-21 will serve not only as bomber, but also as communication hub/server for this

the real danger here is Lost of Communication or worst false information given by enemy
this is the Achilles Heel for new generation of Fighter Jet in development...

Each aerodynamic configuration has advantages and disadvantages.

Turn rates are a relation of lift and thrust, the more lift a better ITR the better Thrust higher STR.

Regardless an aircraft has canards or LEX or Levcons the most important is lift and thrust.

To go for canards is because tailess deltas use the canards for vortex lift and control surface.

There are many reasons why to use canards but canards per say are not a synonym of superiority.

A design configuration has to consider materials, speed, altitude, AoA and then the wing can be chosen.

Deltas use canards because deltas are not good at low speeds and lose lift at STRs.

LEX are fixed and can not be used as control surfaces as canards are used, however this has not been proven a bad feature since Su-27 can do the cobra using horizontal stabilizers

Aerodynamics is a quite complex science

 

[Archibald]

It is kinda interesting that J-20 "proved" that canard and stealth can go along well. Considering Europe love for "eurocanard" shapes, when moving into the 5th or 6th generation fighter realm it might be an important detail.

 

[F-14ATomcat]

It is kinda interesting that J-20 "proved" that canard and stealth can go along well. Considering Europe love for "eurocanard" shapes, when moving into the 5th or 6th generation fighter realm it might be an important detail.

the canard on J-20 is not hidden by the wing, has dihedral creating an extra surface, add the ventral fins a you have more surfaces reflecting and diffracting, J-20 did not prove that, they simply used canards for performance.




These pictures show the horizontal stabilizer is well hidden by the wing on F-22 on a frontal and a rear view


The canard on J-20 never achieved that planform alignment


Su-57 follows the same rule and adds a LEVCON adding the same a canard does but perfectly aligned to the wing

 

[F-14ATomcat]

I'm leaning more towards either 3-surface or canards than cranked deltas.

for a 1990s configuration it is good, but it has some drawbacks among them excessive drag and a very high radar signature, therefore the Su-57 has LEVCONs that do the same canards do, which is shedding a vortex at high AoA and controlling it while deflecting the LEVCON as a canard does, reducing drag and radar signature.



The Su-35/Su-27M was an example of this, the canard increase lift and added some controlability to the lift by deflecting at high AoA and shedding vortices with some degree of control as a LEVCON will do.



Su-57 is the perfection of Su-37/Su-30MS by deleting ventral fins (which help at high AoA) and reducing drag and radar signature with the LEVCON and TCV nozzles by reducing the size of the vertical stabilizers and eliminating the canard

 

[Scott Kenny]

Bigger canards means smaller deflections and also helps with radar absorption.

Small canards like on the advanced Flankers were only done to fix a CG issue.

 

[F-14ATomcat]

Bigger canards means smaller deflections and also helps with radar absorption.

Small canards like on the advanced Flankers were only done to fix a CG issue.

The canards on the Su-30 to Su-37 did indeed fix CG issues true but they also they add vortex control since they are deflected, on F-18E has larger a LERX than F-18A/C to fix CG issues but they can not be deflected since they are fixed LEX.

Any canard by being deflected also changes the vortex position with respect the AoA and Center of Lift.

Now no aircraft configuration is perfect all have trade offs.

The F-18 for example having a large LEX generate vortex lift and it can use a wing with less leading edge wing swept.

Th advantage of Gripen versus F-18 is the canard is not fixed it can be deflected so it is a pitch control device doing what in the F-18 the horizontal stabilizer does. But the wing on the F-18 has less swept and can achieve less lift lost at STR.

A larger canard means larger drag, and larger main wing lift loss due to canard down wash.

Canard are usually smaller than horizontal stabilizers because the wing loses lift, but also require less area due to high pitch acceleration because a higher unstable pitch force.

canards help a lot ITR.

However this is also dependent on wing loading and Thrust to weight ratio.

The maneuverability of the Sukhoi Su-30 at very high angles of attack (AoA) was remarkably appealing. Canard angle, in cooperation with aircraft wing, created a flow pattern whereby, in that position, the fighter still had as much lifting force as possible in order not to stall. The behavior of changing canard angle configuration played an essential role in creating the strong vortex core so that it could delay the stall. The study of vortex dynamics at canard deflection angle gave an essential function in revealing the stall delay phenomenon. In this study, one could analyze the flow patterns and vortex dynamics ability of the Sukhoi Su-30-like model to delay stall due to the influence of canard deflection. The used of water tunnel facilities and computational fluid dynamics (CFD) based on Q-criterion has obtained clear and detailed visualization and aerodynamics data in revealing the phenomenon of vortex dynamics. It was found that between 30° and 40° canard deflection configurations, Sukhoi Su-30-like was able to produce the most robust flow interaction from the canard to the main wing. It was clearly seen that the vortex merging formation above the fighter heads was clearly visible capable of delaying stall until AoA 80°.

Adding a forewing to an aircraft such as LEX and canard will produce a strong vortex that will interact and affect flow over the main wing [17]. This influence will be used to modify the flow so that the aircraft has better flight performance. When the flow above the wing has begun to experience turbulence, the vortex core from the forewing will hit the flow above the wing and make it re-streamline. Forewing configuration will affect changes in vortex structure that occur. Canard has a more flexible configuration due to the ability to adjust the deflection angle.
Several previous researchers have observed many fuselage effects on the types of straight type aircraft body models, such as Chengdu, X-31, and F-18. On the other hand, the fuselage on a curved aircraft body model of the Sukhoi Su-30MKI has admirable maneuverability in high attack angle conditions. Sukhoi Su-30MKI has a unique canard wing configuration, adding the canard in the same height and near the main wing, while most other aircraft use a canard configuration above and in front of the main wing. This high agility allows the aircraft to release weapons in all directions, due to the dynamics of vortices formed on the canard, wings, and body of the aircraft. Therefore, analyzing the occurrence of vortex dynamics becomes a crucial factor indicating lift force at a high attack angle of attack. Thus, flow visualization method is an effective way of determining the phenomenon of vortex dynamics.

Vortex Dynamics Study of the Canard Deflection Angles’ Influence on the Sukhoi Su-30-Like Model to Improve Stall Delays at High AoA

The maneuverability of the Sukhoi Su-30 at very high angles of attack (AoA) was remarkably appealing. Canard angle, in cooperation with aircraft wing, created a flow pattern whereby, in that position, the fighter still had as much lifting force as possible in order not to stall. The behavior of...

www.mdpi.com

 

[lastdingo]

I think the concept of a "fighter" makes little sense in continental air war.
You need a flying long range radar platform, but the kill shot can better be done by something like SM-6. Fighters are expensive, you won't have many on station and saturation attacks would penetrate a fighrer-reliant defence easily.

SAMs in flight are now very equivalent to AAMs, sometimes it's even the same thing.

So what aircraft instead?
A bow & tail rotating AESA radars aircraft with 360x360 degrees radar ability that's survivsble against long range missiles (supercruise to make intercepts terrible guesswork), possibly with hard kill CIWS missiles for survivability.

A 6th generation combat aircraft for Europe

This is blog about the defence against external threats and about the defence of civil liberties.

defense-and-freedom.blogspot.com

 

[Ronny]

I think the concept of a "fighter" makes little sense in continental air war.
You need a flying long range radar platform, but the kill shot can better be done by something like SM-6. Fighters are expensive, you won't have many on station and saturation attacks would penetrate a fighrer-reliant defence easily.

SAMs in flight are now very equivalent to AAMs, sometimes it's even the same thing.

So what aircraft instead?
A bow & tail rotating AESA radars aircraft with 360x360 degrees radar ability that's survivsble against long range missiles (supercruise to make intercepts terrible guesswork), possibly with hard kill CIWS missiles for survivability.

A 6th generation combat aircraft for Europe

This is blog about the defence against external threats and about the defence of civil liberties.

defense-and-freedom.blogspot.com

Fighters are much weaker than SAM in defense but much stronger in offense:
1- They can attack ground targets with immunity if using long range cruise missiles.
2- They can deal with nap of the earth targets easily because they can fly at high altitude
3- Force concentration is significantly easier with fighters because they can relocate quickly

 

[Ainen]

it seem like due to the creation of HOBS missile and TVC, the need for low speed STR is eliminated, so swing wing and straight wing become redundance. Most fighter seem to emphasize high speed capability

Yet few aircraft managed to reach significant part of high speed performance envelope that was here in 1960s, in 3rd gen. And you can almost see how 4th gen aircraft, through their sub generations, became overall slower.

F-35 isn't a reversal because of stealth here, it continued the trend that was already in place. Partially because it's a strike fighter of course, but so were, in all honesty, its predecessors. It is just built for the job.

 

[Ronny]

Yet few aircraft managed to reach significant part of high speed performance envelope that was here in 1960s, in 3rd gen. And you can almost see how 4th gen aircraft, through their sub generations, became overall slower.

F-35 isn't a reversal because of stealth here, it continued the trend that was already in place. Partially because it's a strike fighter of course, but so were, in all honesty, its predecessors. It is just built for the job.

I think it mainly has to do with the fact that launch speed has negligible impact on missile range and average speed compared to launch altitude

AIM-120C Study using Missile-SIM : Part 2 - Launch Condition

Previous Work Status Initial Version of Missile-SIM for Performance evaluation Aerodynamic Validation of Missile-SIM for Trajectory AIM...

jaesan-aero.blogspot.com

 

[F-14ATomcat]

Yet few aircraft managed to reach significant part of high speed performance envelope that was here in 1960s, in 3rd gen. And you can almost see how 4th gen aircraft, through their sub generations, became overall slower.

F-35 isn't a reversal because of stealth here, it continued the trend that was already in place. Partially because it's a strike fighter of course, but so were, in all honesty, its predecessors. It is just built for the job.

Technology in engine power has been the limiting factor.

A fast aircraft requires fast speed, this with jet engines means lots of afterburner or fuel.


YF-12 is huge for a fighter, yes it was very fast had internal weapons bays (stealthy in some way) but it meant a huge aircraft and a very heavy aircraft at high speeds because similar to a rocket it needed lots of fuel and a huge and heavy aircraft will not turn well, first is speed, second wing design and third is weight, it will not be maneuverable.

So by 1970 they saw the next agile fighter was small, subsonic in cruise flight and barely capable of Mach 1.8 in short dashes.

The F-16 is that type aircraft simple intake configuration to keep it light, small to keep it light, the wing was less swept than YF-12, thus it was designbed to fight at Mach 0.6 to 0.9 Mach speeds, it had a horizontal stabilizer.


Russia tried with the MiG-25 to built a more economical fighter, but still it was not a dog fighter nor light.


See F-16 was designed with a single engine, a draggy huge bubble canopy, simple pitot intake

Which supersonic airplanes use Pitot Air intakes?

Which supersonic (fighter) airplanes use the simple Pitot Air Intakes / Normal Shock Inlets? Two examples already seen here on Aviation.SE (one and two) are Dassasult Rafale ($Ma \leq 1.8$) Image

aviation.stackexchange.com

So it went into a different direction than YF-12.

By the 1980s the modern fighters all acknowledge speed is not possible to achieve Mach 3 or Mach 4 with a small fighter, so they have gone for stealth and not speed as the main evasion and defense tactic.



The amount of thrust an engine generates is important. But the amount of fuel used to generate that thrust is sometimes more important, because the airplane has to lift and carry the fuel throughout the flight. Engineers use an efficiency factor, called thrust specific fuel consumption, to characterize an engine's fuel efficiency. "Thrust specific fuel consumption" is quite a mouthful, so engineers usually just call it the engine's TSFC. What does TSFC mean?

The fuel consumption of TSFC is "how much fuel the engine burns each hour." The specific of TSFC is a scientific term meaning "divided by mass or weight." In this case, specific means "per pound (Newton) of thrust." The thrust of TSFC is included to indicate that we are talking about gas turbine engines. There is a corresponding brake specific fuel consumption (BSFC) for engines that produce shaft power. Gathering all the terms together, TSFC is the mass of fuel burned by an engine in one hour divided by the thrust that the engine produces. The units of this efficiency factor are mass per time divided by force (in English units, pounds mass per hour per pound; in metric units, kilograms per hour per Newton).

Mathematically, TSFC equals the engine fuel mass flow rate (mdot f) divided by the thrust (F)

TSFC = mdot f / F

If we divide both numerator and denominator by the engine airflow (mdot 0), obtain another form of the equation in terms of the fuel to air ratio (f), and the specific thrust (Fs).

TSFC = f / Fs

Engineers use the TSFC factor several different ways. If we compare the TSFC for two engines, the engine with the lower TSFC is the more fuel efficient engine. Let's consider two examples:

• Suppose we had two Engines, A and B, that produced the same amount of thrust. And suppose that Engine A uses only half the fuel per hour that Engine B uses. We would then say that Engine A is more fuel efficient than Engine B. If we compute the TSFC for Engines A and B, the TSFC of Engine A is one half the value of Engine B.
• Looking at it another way, suppose we had two Engines, C and D, and we fed the same amount of fuel per hour to each of them. Suppose Engine C produces twice the thrust of Engine D. Then we are getting more thrust from Engine C for the same amount of fuel, and we would say that Engine C is more fuel efficient. Again, if we compute the TSFC for Engines C and D, the TSFC of Engine C is one half the value of Engine D.

Specific Fuel Consumption

 

[riggerrob]

It is easier to harder a big aircraft than a small drone I think

I would disagree. The smaller the electronic volume, the less armour/shielding you need. Shorter cable routings from antenni to CPUs need shorter and lighter armoured cables.