What is the best aerodynamic configuration for a fighter aircraft?

[Ronny]

Let say for a moment, we ignore boring limitation like production cost, maintenance issue, complexity, stealth characteristic. What would be the best aerodynamic configuration for a fighter jet? and why ?. I'm not talking about the
Tandem configuration with both rear horizontal tail and canard
Advantage:
Can generate huge amount of lift at low speed and low AoA, yet still allow your aircraft reaching high speed. Arguably the only other configuration along with VG that allow heavy fighter to land on carrier
Better lift generation for high AoA maneuver





Long arm canard:
Advantages: low drag, especially at supersonic speed, good moment for turning at high speed, high altitude


Variable swept wing:
Advantage: arguably the only kind of wing that can give optimum L/D ratio at all speed range. It can give the highest amount of lift at low speed, low AoA and lowest amount of drag at high speed
VG wing give lowest landing speed and highest top speed at the same time



Close coupled canard:
Advantages: low drag especially at supersonic speed. Can generate a lot of lift for turning, good high AoA characteristic

 

[Halcyon66]

Unmanned, no G restriction.

Regards,

 

[Ronny]

Unmanned.

Regards,

Unmanned is not an aerodynamic configuration though, it is a way of control

 

[Halcyon66]

Yes, yet due to the considerable added weight of the airframe to keep the human alive/safe you sacrifice aerodynamics.

Regards,

 

[overscan (PaulMM)]

Not unsurprisingly the answer is "it depends what you want".

What are you most concerned with? Subsonic /supersonic turn rate (sustained or instantaneous), speed at high/low altitude, range?

Every configuration is a compromise, no one is objectively best.

 

[Ronny]

Yes, yet due to the considerable added weight of the airframe to keep the human alive/safe you sacrifice aerodynamics.

Regards,

Yes, but even UAV can have different aerodynamic configuration

 

[Halcyon66]

Not unsurprisingly the answer is "it depends what you want".

What are you most concerned with? Subsonic /supersonic turn rate (sustained or instantaneous), speed at high/low altitude, range?

Every configuration is a compromise, no one is objectively best.

Add to the above primer, minus the human and you have an unlimited design configuration tree.

Regards,

 

[Ronny]

What are you most concerned with? Subsonic /supersonic turn rate (sustained or instantaneous), speed at high/low altitude, range?

Every configuration is a compromise, no one is objectively best.

I think variable swept wing can arguably win every single criteria there.
You want high sustained turn rate just sweep forward, you want high speed just sweep back.

 

[Halcyon66]

Variable swept wing requires complex mechanisms.

X-29 config was an outside the box and also the X-31 in regard to AOA and the like.

https://www.nasa.gov/wp-content/uploads/2021/09/fs-008-afrc.pdf

https://www.nasa.gov/wp-content/uploads/2021/09/272700main_fs-009-dfrc.pdf

Regards,

 

[Nx4eu]

If cost and complexity is no issue why would you go for these basic layouts. You can start doing ridiculous things with the control surfaces and aerodynamics. I'm thinking reaction control thrusters, 3d tvc, all angle variable sweep wing, variable angle rudders.. Go all out build one of those ace combat fighters or a flying transformers.

 

[Ronny]

If cost and complexity is no issue why would you go for these basic layouts. You can start doing ridiculous things with the control surfaces and aerodynamics. I'm thinking reaction control thrusters, 3d tvc, all angle variable sweep wing, variable angle rudders.. Go all out build one of those ace combat fighters or a flying transformers.

Yeah but then maybe there is weight penalty, reaction control thruster is not quite useful in atmosphere

 

[Ronny]

Variable swept wing requires complex mechanisms.

X-29 config was an outside the box and also the X-31 in regard to AOA and the like.

https://www.nasa.gov/wp-content/uploads/2021/09/fs-008-afrc.pdf

https://www.nasa.gov/wp-content/uploads/2021/09/272700main_fs-009-dfrc.pdf

Regards,

X-29 can’t go very fast if I recall correctly, and 3D TVC made X-29 configuration redundance

 

[Nx4eu]

What about a variable sweep wing that can go from forward swept to backward swept so from X-29 to tomcat-esque

 

[Ronny]

What about a variable sweep wing that can go from forward swept to backward swept so from X-29 to tomcat-esque

I feel like there is almost no benefit to swept forward. Or maybe there is but mostly for post stall maneuver but that can better be done by 3D TVC

 

[Halcyon66]

How long is a piece of string?

Stealth, Sensors, Or Speed: What Makes A Fighter Jet The World's Best?

Here’s What You Need To Remember: Aircraft design is a compromise, and if speed and maneuverability come at the expense of range, payload and stealth, then this is a bad trade if situational awareness is becoming the prime determinant of victory. On the other hand, one expects that all things...

nationalinterest.org

Aircraft design is a compromise, and if speed and maneuverability come at the expense of range, payload and stealth, then this is a bad trade if situational awareness is becoming the prime determinant of victory.

There is always a trade-off.

Regards,

 

[Nx4eu]

This I find interesting too

 

[Halcyon66]

 

[Halcyon66]

Hollywood come on down........

Regards,

 

[red admiral]

Unmanned, no G restriction.

Regards,

The airframe will still be designed to a g limit after which it breaks. You can make this higher than for a crewed aircraft, but this adds mass.

Design is a trade off

 

[martinbayer]

The airframe will still be designed to a g limit after which it breaks. You can make this higher than for a crewed aircraft, but this adds mass.

Design is a trade off

Chasing/finding the multidimensional sweet spot/knee in the curve is one of the mental/intellectual highs of aerospace engineering.

 

[Archibald]

I use to say the Mirage 4000 having just one fin instead of 4 found on the F-15 and Su-27, couldn't do any bad to drag. Plus the delta is good for internal fuel, meanwhile FBW corrects its flaws. The Rafale by itself is a shrunk 4000 shape (from F-15 to F-18 size) with the air intakes moved out of the canard way, so that it can better interfere with the delta wing : improved agility...

 

[Rhinocrates]

Not unsurprisingly the answer is "it depends what you want".

What are you most concerned with? Subsonic /supersonic turn rate (sustained or instantaneous), speed at high/low altitude, range?

Every configuration is a compromise, no one is objectively best.

Moreover, from The Wild One:

Mildred : Hey Johnny, what are you rebelling against?

Johnny : Whadda you got?

What have you got then? What do I need to have to counter that? 'Fighter' is a very broad term. It can mean interceptor, or it can mean air superiority, or it can mean multirole, or BVR, or...

 

[Ronny]

I use to say the Mirage 4000 having just one fin instead of 4 found on the F-15 and Su-27, couldn't do any bad to drag. Plus the delta is good for internal fuel, meanwhile FBW corrects its flaws. The Rafale by itself is a shrunk 4000 shape (from F-15 to F-18 size) with the air intakes moved out of the canard way, so that it can better interfere with the delta wing : improved agility...

delta seem to be very good in term of reducing drag but somewhat lacking in lift generation at low AoA compared to VG wing

 

[Justo Miranda]

I really like fighters and their advanced aerodynamic configurations. I have devoted most of my books to this topic, but in my opinion, its usefulness will decline considerably in the coming years and the concept will not survive the next serious war between technological powers. Anyone betting a few beers?

 

[Ronny]

I really like fighters and their advanced aerodynamic configurations. I have devoted most of my books to this topic, but in my opinion, its usefulness will decline considerably in the coming years and the concept will not survive the next serious war between technological powers. Anyone betting a few beers?

I think fighters jet are among the most versatile weapon that a nation can have. Short of anti everything except submarine weapons. I personally think fighter jet will survive for much longer than tank and helicopter

 

[Desertfox]

More control surfaces is better. So F-14 + canards + TVC

 

[Ronny]

More control surfaces is better. So F-14 + canards + TVC

that probably very very heavy and bad for acceleration though?

 

[Nx4eu]

that probably very very heavy and bad for acceleration though?

I think the extra weight can be afforded with new technologies which can construct a lighter airframe, and new more powerful engines with thrust to weight ratios >10.

 

[Justo Miranda]

I think fighters jet are among the most versatile weapon that a nation can have. Short of anti everything except submarine weapons. I personally think fighter jet will survive for much longer than tank and helicopter

Historically, fighters were developed to prevent enemy reconnaissance aircraft from photographing ground defenses. During the 1920s, Douet's stupid ideas about mastery of the air forced all aeronautical powers to continue the development of fighters for fear of a deadly gas bombing offensive. After the success of the Luftwaffe in Spain, the fighter became the weapon of panic and during the Cold War the fear of strategic bombers armed with nuclear bombs intensified the need for fighters, but when the threat changed to intercontinental missiles the situation reverted to Spitfire against V-2.

The only weapon against strategic missiles was the threat of another strategic missile. In Vietnam the fighter was no longer essential and failed when they tried to convert it into a bomber.

After the downing of Gary Powers, SAMs dominated the skies and a small war in Europe showed that stealth fighter-bombers were also vulnerable to randomly fired autocannons.

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.

How many Israeli F-15s would have been needed to get the same result as the exploding phones?

Fighter pilots continue to climb into planes on the left side like 19th-century cavalry riders, someday not too distant they will do so for the last time.

 

[sferrin]

 

[Justo Miranda]

Space fighters cannot maneuver like airplanes in a vacuum, they lack autonomy, firepower, protection against heavy weapons and above all engine power, paradoxically they will always be slower than a large warship.

 

[F-14ATomcat]

In My opinion these are the best configurations for modern 5th generation fighters.

Why Su-57?

Levcons do not generate the drag canards do and still control vortex position and aerodynamic center of lift position and are good for stealth.

Has TVC nozzles reducing the size of all moving vertical tails

The weapons bays on the lower part of the wing LEX, also reduces loss of lift and add space for a weapon

basically work as dropped wintips but carry a weapon

Widely separated engines improve TVC nozzles and add space for fuel and weapons and still generating fuselage lift.

It still has a horizontal tail, allowing good roll control when coupled with TVC nozzles

On Su-75 the lack of horizontal tail improves weight reduction and the extra area reflecting radar waves but still has an intake with a lower bump for the DSI intake by wrapping the intake lip around the fuselage.


For a 4th Generation



For a third generation

Rafale undoubtedly the best design because the close coupled canards assure the Delta wing LEX has extra strengthened vortices with some control, the intakes are simple fixed types but the semi ventral semi under the wing shape is good for sideslip and high AoA, definitively the most beautiful 4th generation fighter.





why? simple the best supersonic wing with the lowest radar signature for a third generation fighter was J-35 Drakken, the intakes were low drag and hided the engine fan compressor blades well.

(The Drakken wing is appearing again in the modern 6th generation designs)

 

[Justo Miranda]

These Russian planes are impressive, powerful, agile and very well armed machines, but who are they going to fight?

In a major war, enemy stealth bombers will launch their intelligent cruise missiles from far away and descend to very low altitude and are very difficult to detect and shoot down. Those missiles will in turn launch hundreds of mini drones that will disperse to attack the enemy's vital centers. These drones can also be launched from civilian aircraft, submarines and even fake tourists. They can be implanted weeks before the start of hostilities and wait idle on the rooftops of the enemy capital, charging their batteries with sunlight until a satellite order activates them and assigns them targets. Who is going to stop them?

 

[F-14ATomcat]

These Russian planes are impressive, powerful, agile and very well armed machines, but who are they going to fight?

In a major war, enemy stealth bombers will launch their intelligent cruise missiles from far away and descend to very low altitude and are very difficult to detect and shoot down. Those missiles will in turn launch hundreds of mini drones that will disperse to attack the enemy's vital centers. These drones can also be launched from civilian aircraft, submarines and even fake tourists. They can be implanted weeks before the start of hostilities and wait idle on the rooftops of the enemy capital, charging their batteries with sunlight until a satellite order activates them and assigns them targets. Who is going to stop them?

In aerodynamics they are great, but if you tell me what are the most dangerous weapons are not aircraft but biological weapons since they could kill millions, leave no radioactivity, no nuclear winter and still win WWIII

 

[Justo Miranda]

In aerodynamics they are great, but if you tell me what are the most dangerous weapons are not aircraft but biological weapons since they could kill millions, leave no radioactivity, no nuclear winter and still win WWIII

I agree, except on the problem of pre-vaccinating your own people without the enemy suspecting. Also, the enemy has viruses against which there are no antidotes and only needs a few guys to survive to execute their revenge, even an automatic mechanism could do it... I think everyone knows the terrifying idea of the dead man's hand. Finally, it's possible that the world's elites have developed a universal antidote for their own protection, and you'd be doing them a favor by eliminating surplus populations.

Personally, what scares me are the ideas that artificial intelligence can provide for the military, because machines by their very nature do not think like us. I think we're already seeing some of those ideas in action and they've taken everyone by surprise.

 

[Ronny]

Historically, fighters were developed to prevent enemy reconnaissance aircraft from photographing ground defenses. During the 1920s, Douet's stupid ideas about mastery of the air forced all aeronautical powers to continue the development of fighters for fear of a deadly gas bombing offensive. After the success of the Luftwaffe in Spain, the fighter became the weapon of panic and during the Cold War the fear of strategic bombers armed with nuclear bombs intensified the need for fighters, but when the threat changed to intercontinental missiles the situation reverted to Spitfire against V-2.

The only weapon against strategic missiles was the threat of another strategic missile. In Vietnam the fighter was no longer essential and failed when they tried to convert it into a bomber.

After the downing of Gary Powers, SAMs dominated the skies and a small war in Europe showed that stealth fighter-bombers were also vulnerable to randomly fired autocannons.

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.

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.

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.

How many Israeli F-15s would have been needed to get the same result as the exploding phones?

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

 

[martinbayer]

Historically, fighters were developed to prevent enemy reconnaissance aircraft from photographing ground defenses. During the 1920s, Douet's stupid ideas about mastery of the air forced all aeronautical powers to continue the development of fighters for fear of a deadly gas bombing offensive. After the success of the Luftwaffe in Spain, the fighter became the weapon of panic and during the Cold War the fear of strategic bombers armed with nuclear bombs intensified the need for fighters, but when the threat changed to intercontinental missiles the situation reverted to Spitfire against V-2.

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

 

[Scott Kenny]

I really like fighters and their advanced aerodynamic configurations. I have devoted most of my books to this topic, but in my opinion, its usefulness will decline considerably in the coming years and the concept will not survive the next serious war between technological powers. Anyone betting a few beers?

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.

 

[aim9xray]

Best aerodynamic configuration for a fighter? No bullet holes.

 

[Scott Kenny]

As to preferred configuration?

Large canards like the J-20. Because you don't have the horizontal stabilizers subtracting from your total lift to keep the plane balanced.

Or rather, like the FFR-31 'Sylphid' from the Yukikaze anime.

Okay, yeah, that's a 3-surface plane not especially "large canards" like the J-20.