ADA Tejas Mark-II/Medium Weight Fighter

[Lonewolf]

Its difficult to have any fruitful discussion if people keep changing their stance and arguments.

This is what Legend of this forum said:

I counterd that with hurjet. It is pitched and has beaten many other jets to reach top3.Simple

Top 3 , are you sure ? Which jet it has beaten ?

 

[DeadCritic]

Either you can copy the existing design or you can make a completely new design from scratch.Only one of above 2 is possible. There is no 3rd option. Only thing u may do is a slight change, which won't make huge difference in appearance, and the OEM whose design u "slightly changed" will call you a thief. U cannot make a huge difference in existing proven design , because the existing design is an optimisation after several iterations. U cannot optimize it further.Simple

Finally someone responded to the question rather than questioning the question.

Thanks Vamsi.

 

[Lonewolf]

@DeadCritic i don't know how much you know about aerodynamic but even a screw affect your aircraft aerodynamics performance , so you can't just change everything like it's a cup of tea , if u read more into this you will realise the fault in you argument

 

[DeadCritic]

@DeadCritic i don't know how much you know about aerodynamic but even a screw affect your aircraft aerodynamics performance , so you can't just change everything like it's a cup of tea , if u read more into this you will realise the fault in you argument

Following formula 1 sports which is heavily aero focused for over a decade now.
I am new to defense sector but not to other stuff.

About your calmness suggestion :
I am simple man, I ask a specific question and I expect an answer or query like you did.
But I do not accept someone discarding my questions or making fun of it.

I am very calm with my question, if you read my first post you will see I said : I am new to it so everyone can be bit supportive. But I received rough response.

and I don't know why flag is not shown and I don't know when it be shown.

 

[Lonewolf]

Following formula 1 sports which is heavily aero focused for over a decade now.
I am new to defense sector but not to other stuff.

About your calmness suggestion :
I am simple man, I ask a specific question and I expect an answer or query like you did.
But I do not accept someone discarding my questions or making fun of it.

I am very calm with my question, if you read my first post you will see I said : I am new to it so everyone can be bit supportive. But I received rough response.

and I don't know why flag is not shown and I don't know when it be shown.

Formula one don't fly and won't go supersonic . That's the deal , aircraft body heats up in seconds

 

[DeadCritic]

Formula one don't fly and won't go supersonic . That's the deal , aircraft body heats up in seconds

does aircraft body melts with in seconds? Because I fail to understand your point.
Formula 1 reference was for aerodynamics and I think aircraft shape largely remains same throughout the flight .Hence aero remains same.
Aero science fundamentals are same for all.

Its ok buddy,I am fine with what Vamsi said.

 

[Lonewolf]

does aircraft body melts with in seconds? Because I fail to understand your point.
Formula 1 reference was for aerodynamics and I think aircraft shape largely remains same throughout the flight .Hence aero remains same.
Aero science fundamentals are same for all.

Its ok buddy,I am fine with what Vamsi said.

Not melts but heat up , that's why precision in aerodynamics study is higher than a F1 car , you can't expect a planar rectangular sheet of metal to fly supersonic along its plane , too much drag , similar if u change frontal wings , then airflow after that interaction will change and u need to make amendments to it , so if u are gonna use a already used design and make amendments to it , you will end with a totally different aircraft . Atax it will look similar , and in case of delta wings , the changes will be drastic

 

[MonaLazy]

Absolute newbie to defense.

Welcome!

As I read about Tejas, its said that it its draggy and not very efficient aero wise.
Why not just copy the best air frame (visual shape is not a secret I think) and pack you stuff in it?atleast jet would swift and efficient. I read jets which are using same engine and are heavier can cruise supersonic and Tejas cannot. The sole reason for this is aero issues.

Why not copy the best airframe?
It already does:

Tejas: thoughts on an unusual wing

India has a new light fighter, the indigenous Tejas (which translates as ‘radiance’). Other than its small size, there are two more unusual things about Tejas: large control surfaces wh…

hushkit.net

Delta Wings
The delta planform offers the possibility of using a low thickness to chord ratio wing, which simultaneously provides good wing area, a highly swept leading edge, and low transonic and supersonic wave drag, while still providing reasonable internal volume for structure and fuel.

The validity of this approach is illustrated by the large number of fighter aircraft using delta, or near delta planforms, some as pure delta wings without additional stabilising or control surfaces, others with either tailplanes or canards. Examples of pure deltas include the Dassault Mirage series and the Convair F-102 and F-106. Examples of canard deltas include Typhoon and Rafale, while the Lockheed Martin F-22 and even the McDonnell F-15 may be considered as tailed near-deltas.

What's the problem then?
We need to first understand the Whitcomb area rule:



Aeroplane design is a delicate balancing act. Tejas trades off area rule for lower weight/induced drag and better pressure recovery which are much more important for its small size, but it pays the price in trans-sonic acceleration because of wave drag from .85 Mach to little above Mach 1 (which demands area rule compliance). The Mk1 Tejas' intakes are shielded by the wing which helps straighten and redirect airflow to the intakes during high angle of attack manoeuvres.

Why is it small? because IAF wanted to use existing infra on our frontline airbases- so the Tejas envisioned in the 80s was supposed to fit snugly inside the existing HAS (Hardened Aircraft Shelter) for Mig-21- and strictly be no longer. This is addressed in the future Mk2:

Tracking The Tejas: How The Tejas Mk2 Design Became The Medium Weight Fighter | Delhi Defence Review

delhidefencereview.com

[*]If Mk2 is already so much better, what makes Mk1A export ready and quality product? and why Mk2 is not on market yet ?

There is no physical Mk2 just yet. We are all waiting for it to be born!

How Tejas Mark 2 is evolving into a bigger, powerful fighter

www.ajaishukla.com

Apologies if questions are very basic and stupid.

There are no stupid questions.

Formula 1 reference was for aerodynamics and I think aircraft shape largely remains same throughout the flight .Hence aero remains same.
Aero science fundamentals are same for all.

Which F1 car have you seen go supersonic?

Your assumptions are wrong.

 

[DeadCritic]

Welcome!



Why not copy the best airframe?
It already does:

Tejas: thoughts on an unusual wing

India has a new light fighter, the indigenous Tejas (which translates as ‘radiance’). Other than its small size, there are two more unusual things about Tejas: large control surfaces wh…

hushkit.net

Delta Wings
The delta planform offers the possibility of using a low thickness to chord ratio wing, which simultaneously provides good wing area, a highly swept leading edge, and low transonic and supersonic wave drag, while still providing reasonable internal volume for structure and fuel.

The validity of this approach is illustrated by the large number of fighter aircraft using delta, or near delta planforms, some as pure delta wings without additional stabilising or control surfaces, others with either tailplanes or canards. Examples of pure deltas include the Dassault Mirage series and the Convair F-102 and F-106. Examples of canard deltas include Typhoon and Rafale, while the Lockheed Martin F-22 and even the McDonnell F-15 may be considered as tailed near-deltas.

What's the problem then?
We need to first understand the Whitcomb area rule:



Aeroplane design is a delicate balancing act. Tejas trades off area rule for lower weight/induced drag and better pressure recovery which are much more important for its small size, but it pays the price in trans-sonic acceleration because of wave drag from .85 Mach to little above Mach 1 (which demands area rule compliance). The Mk1 Tejas' intakes are shielded by the wing which helps straighten and redirect airflow to the intakes during high angle of attack manoeuvres.

Why is it small? because IAF wanted to use existing infra on our frontline airbases- so the Tejas envisioned in the 80s was supposed to fit snugly inside the existing HAS (Hardened Aircraft Shelter) for Mig-21- and strictly be no longer. This is addressed in the future Mk2:

Tracking The Tejas: How The Tejas Mk2 Design Became The Medium Weight Fighter | Delhi Defence Review

delhidefencereview.com

There is no physical Mk2 just yet. We are all waiting for it to be born!

How Tejas Mark 2 is evolving into a bigger, powerful fighter

www.ajaishukla.com

There are no stupid questions.




Which F1 car have you seen go supersonic?

Your assumptions are wrong.

This is perfect.
Thanks

Which F1 car have you seen go supersonic?
Your assumptions are wrong.

It was reference.. implying that I do understand aerodynamics to some extent.
I never said Jet and f1 aero design principles are same.

So you read it wrong.

straw man fallacy link

 

[MonaLazy]

Following formula 1 sports which is heavily aero focused for over a decade now.

It was reference.. implying that I do understand aerodynamics to some extent.

No sir, you don't! You made an assumption that you understand aerodynamics by following F1 for over a decade. it don't work like that- otherwise, all University aero departments & wind tunnels in the world can be shut down immediately if we could churn out experts from simply sitting in front of the TV.

The area rule was a hard-fought discovery which was the result of painstaking labour from the late 40s to early 50s by some very very creative people & very fittingly for the assumption you make, they had to unlearn some of the aerodynamics they had previously learnt (they also thought they knew!).

Dr. Busemann delivered a radical message: Bernoulli's Theorem, a standing rule of aeronautics stating that when airflow was made narrower, the speed of that air would increase, did not apply at transonic or supersonic speeds. This ultimately helped Whitcomb realize that he couldn't look at the wing and fuselage as two separate parts anymore. The entire cross-sectional area of the design had to be designed with as smooth a curve as possible.

In late 1951, Whitcomb tested a swept-back wing-fuselage combination in the now-transonic Eight-Foot High-Speed Tunnel.7 Tuft surveys, which used small pieces of yarn taped onto airfoil and fuselage sections, were conducted to look at airflow disturbances. Coverings with pressure-sensitive openings were put on model sections to determine the velocity of the air over particular areas, and Schlieren photographs were used to look at the shock wave characteristics of the model at transonic speeds.8

The results, especially those revealed by the Schlieren photographs, showed that the shock waves created as the airflow approached the speed of sound were different and bigger than anticipated. Undoubtedly, it was the losses from these unexpected shock patterns that was causing the sharp increase in drag at transonic speeds. But the question of what was causing the shockwaves still had to be answered before researchers could try to find a way to combat the phenomenon.

Several weeks later, a world renowned German aerodynamicist named Dr. Adolf Busemann, who had come to work at Langley after World War II, gave a technical symposium on transonic airflows. In a vivid analogy, Busemann described the stream tubes of air flowing over an aircraft at transonic speeds as pipes, meaning that their diameter remained constant. At subsonic speeds, by comparison, the stream tubes of air flowing over a surface would change shape, become narrower as their speed increased. This phenomenon was the converse, in a sense, of a well-known aerodynamic principle called Bernoulli's theorem, which stated that as the area of an airflow was made narrower, the speed of the air would increase. This principle was behind the design of venturis,9 as well as the configuration of Langley's wind tunnels, which were "necked down" in the test sections to generate higher speeds.10

But at the speed of sound, Busemarm explained, Bernoulli's theorem did not apply. The size of the stream tubes remained constant. In working with this kind of flow, therefore, the Langley engineers had to look at themselves as "pipefitters." Busemann's pipefitting metaphor caught the attention of Whitcomb, who was in the symposium audience. Soon after that Whitcomb was, quite literally, sitting with his feet up on his desk one day, contemplating the unusual shock waves he had encountered in the transonic wind tunnel. He thought of Busemann's analogy of pipes flowing over a wing-body shape and suddenly, as he described it later, a light went on.

The shock waves were larger than anticipated, he realized, because the stream tubes did not get narrower or change shape, meaning that any local increase in area or drag would affect the entire configuration in all directions, and for a greater distance. More importantly, that meant that in trying to reduce the drag, he could not look at the wing and fuselage as separate entities. He had to look at the entire cross-sectional area of the design and try to keep it as smooth a curve as possible as it increased and decreased around the fuselage, wing and tail. In an instant of clarity and inspiration, he had discovered the area rule.

In practical terms, the area rule concept meant that something had to be done in order to compensate for the dramatic increase in cross-sectional area where the wing joined the fuselage. The simplest solution was to indent the fuselage in that area, creating what engineers of the time described as a "Coke bottle" or "Marilyn Monroe" shaped design. The indentation would need to be greatest at the point where the wing was the thickest, and could be gradually reduced as the wing became thinner toward its trailing edge. If narrowing the fuselage was impossible, as was the case in several designs that applied the area rule concept, the fuselage behind or in front of the wing needed to be expanded to make the change in crosssectional area from the nose of the aircraft to its tail less dramatic.11

The Whitcomb Area Rule: NACA Aerodynamics Research And Innovation

How the 'Area Rule' Dictates Plane Design

The mathematics of cross-section.

www.popularmechanics.com

 

[DeadCritic]

No sir, you don't! You made an assumption that you understand aerodynamics by following F1 for over a decade. it don't work like that- otherwise, all University aero departments & wind tunnels in the world can be shut down immediately if we could churn out experts from simply sitting in front of the TV.

The area rule was a hard-fought discovery which was the result of painstaking labour from the late 40s to early 50s by some very very creative people & very fittingly for the assumption you make, they had to unlearn some of the aerodynamics they had previously learnt (they also thought they knew!).



In late 1951, Whitcomb tested a swept-back wing-fuselage combination in the now-transonic Eight-Foot High-Speed Tunnel.7 Tuft surveys, which used small pieces of yarn taped onto airfoil and fuselage sections, were conducted to look at airflow disturbances. Coverings with pressure-sensitive openings were put on model sections to determine the velocity of the air over particular areas, and Schlieren photographs were used to look at the shock wave characteristics of the model at transonic speeds.8

The results, especially those revealed by the Schlieren photographs, showed that the shock waves created as the airflow approached the speed of sound were different and bigger than anticipated. Undoubtedly, it was the losses from these unexpected shock patterns that was causing the sharp increase in drag at transonic speeds. But the question of what was causing the shockwaves still had to be answered before researchers could try to find a way to combat the phenomenon.

Several weeks later, a world renowned German aerodynamicist named Dr. Adolf Busemann, who had come to work at Langley after World War II, gave a technical symposium on transonic airflows. In a vivid analogy, Busemann described the stream tubes of air flowing over an aircraft at transonic speeds as pipes, meaning that their diameter remained constant. At subsonic speeds, by comparison, the stream tubes of air flowing over a surface would change shape, become narrower as their speed increased. This phenomenon was the converse, in a sense, of a well-known aerodynamic principle called Bernoulli's theorem, which stated that as the area of an airflow was made narrower, the speed of the air would increase. This principle was behind the design of venturis,9 as well as the configuration of Langley's wind tunnels, which were "necked down" in the test sections to generate higher speeds.10

But at the speed of sound, Busemarm explained, Bernoulli's theorem did not apply. The size of the stream tubes remained constant. In working with this kind of flow, therefore, the Langley engineers had to look at themselves as "pipefitters." Busemann's pipefitting metaphor caught the attention of Whitcomb, who was in the symposium audience. Soon after that Whitcomb was, quite literally, sitting with his feet up on his desk one day, contemplating the unusual shock waves he had encountered in the transonic wind tunnel. He thought of Busemann's analogy of pipes flowing over a wing-body shape and suddenly, as he described it later, a light went on.

The shock waves were larger than anticipated, he realized, because the stream tubes did not get narrower or change shape, meaning that any local increase in area or drag would affect the entire configuration in all directions, and for a greater distance. More importantly, that meant that in trying to reduce the drag, he could not look at the wing and fuselage as separate entities. He had to look at the entire cross-sectional area of the design and try to keep it as smooth a curve as possible as it increased and decreased around the fuselage, wing and tail. In an instant of clarity and inspiration, he had discovered the area rule.

In practical terms, the area rule concept meant that something had to be done in order to compensate for the dramatic increase in cross-sectional area where the wing joined the fuselage. The simplest solution was to indent the fuselage in that area, creating what engineers of the time described as a "Coke bottle" or "Marilyn Monroe" shaped design. The indentation would need to be greatest at the point where the wing was the thickest, and could be gradually reduced as the wing became thinner toward its trailing edge. If narrowing the fuselage was impossible, as was the case in several designs that applied the area rule concept, the fuselage behind or in front of the wing needed to be expanded to make the change in crosssectional area from the nose of the aircraft to its tail less dramatic.11

The Whitcomb Area Rule: NACA Aerodynamics Research And Innovation

How the 'Area Rule' Dictates Plane Design

The mathematics of cross-section.

www.popularmechanics.com

I could easily understand what is said in the video.
That proves I have decent understanding.

Which does not make me expert developer or scientist but it does allow me to grasp certain concepts on high level.
Copy pasting things here won't make you smart.
Better invest sometime in reading skills.

It was reference.. implying that I do understand aerodynamics to some extent.

I hope you know what "to some extent" means.
As far as my understanding goes : It clearly means > I know this thing in bits and pieces.

I feel sorry for you.

No sir, you don't! You made an assumption that you understand aerodynamics by following F1 for over a decade.

So you mean formula 1 do not use Aerodynamics? or the aero you are boasting here is altogether a difference science.

in last,
I will paste a simple definition and I hope you read it well this time.

Aerodynamics is the way objects move through air. The rules of aerodynamics explain how an airplane is able to fly. Anything that moves through air is affected by aerodynamics, from a rocket blasting off, to a kite flying.

and fundamentals are same for all objects.

I appreciate your first post which was a detailed answer to my question but this discussion is giving a bad taste.
I am done here.

 

[MonaLazy]

nonsense

You don't get it, do you?

 

[karn]

Aerodynamics of the supersonic and subsonic regimes are quite different . Formula 1 is not equal to fighter jets . Besides here the role of lift is inverse .

 

[THESIS THORON]

You don't get it, do you?

yes professor Mona

 

[Kalkioftoday]

Mr Legend : turkey hurjet pura ho gya ? kab hua flight I don't know. May be you know alot more than me.
still it is pitched and in competition .

So I guess your argument fails to hold.

You see, you don't pitch which you don't have and if you are not a grade A stupid, you don't put your money on something which doesn't even exist. Hürjet doesn't exist anywhere. Neither in turkish airforce nor in malaysian competition. Ignore the media and fanboy claims. No smart airforce will buy an foreign aircraft which didn't even attain it's IOC and Hürjet getting it's IOC is still half a decade away and Malaysia won't wait for that long. There are rules and regulations in place to develop, test and certify a fighter jet and these thing takes time. Even though most of the hardwork are being done by the BAE systems but still they cannot skip or shorten these processes. Many turko fanboys who are saying that they will roll out the hurjet today, fly it tomorrow and start mass production the next day are nothing but bunch of delusional fool and the people who were tweeting that hürjet is competing with Tejas are also the same.

 

[ObiWanKenobi]

I interviewed for a job with Renault F1 back in the day just after my masters. Despite no offers at the time, I said no because of bad wage, no room for development, 70+ hour working weeks and high levels of burnout and turnover. Surprised EU/UK labour laws let these guys function - I suppose you can pass off any exploitation when its a 'sport'.

However, I would definitely not underestimate the aerodynamics they use in those cars. In many ways, a lot more complex than aircraft. Complexity arising from things like:

1. The need to quickly do basic CFD on part designs, testing them in the tunnel and then possibly on the car within 2 weeks. So they just have loads of high quality aero grads working day/night doing a large number of mundane yet tedious jobs. If you are lucky, over your 2-3 years there you might find one of your parts tested on the car. In a way its a crowd sourcing of designs based on a large pool of cheap high quality labour (all of Airbus had like 80 people doing CFD at that time and Renault F1 had 40 - absolute joke).

2. They have SO MANY surfaces, all optimised to create drag for downforce - so you get very interesting interactions. I mean, some effects are downright black magic - just google 'F1 vortices' and enjoy the images section for next 2 hours.

That said, I don't want to get into this exchange extrapolating F1 understanding to aircraft. Just wanted to share my experience of that day when I got an interesting insight into the workings of Renault F1. For which they were supposed to reimburse travel expenses but didn't.

 

[ManhattanProject]

I could easily understand what is said in the video.
That proves I have decent understanding.

Which does not make me expert developer or scientist but it does allow me to grasp certain concepts on high level.
Copy pasting things here won't make you smart.
Better invest sometime in reading skills.

I hope you know what "to some extent" means.
As far as my understanding goes : It clearly means > I know this thing in bits and pieces.

I feel sorry for you.

So you mean formula 1 do not use Aerodynamics? or the aero you are boasting here is altogether a difference science.

in last,
I will paste a simple definition and I hope you read it well this time.

Aerodynamics is the way objects move through air. The rules of aerodynamics explain how an airplane is able to fly. Anything that moves through air is affected by aerodynamics, from a rocket blasting off, to a kite flying.

and fundamentals are same for all objects.

I appreciate your first post which was a detailed answer to my question but this discussion is giving a bad taste.
I am done here.

Someone takes time to give you a proper reply and show you how out of dept you are and your reaction is to take offence?
Dude you need to eat a humble pie, you need to know you are not an expert, knowing little might as well be worse than knowing nothing. There will always be people who know more than you and are smarter than you, when they speak learn to listen to them.
As an esteemed pakistani once said " stop being so proudy."

 

[DeadCritic]

Someone takes time to give you a proper reply and show you how out of dept you are and your reaction is to take offence?
Dude you need to eat a humble pie, you need to know you are not an expert, knowing little might as well be worse than knowing nothing. There will always be people who know more than you and are smarter than you, when they speak learn to listen to them.
As an esteemed pakistani once said " stop being so proudy."

Instead of poking and sharing unwanted gyan.. You could have pointed out where I said I am an expert or I know better than someone here?
If you misread or misquote, that's not my problem.
I stopped responding because I realized people here just assume they know everything better.

and I don't need to learn anything from some random keyboard warrior.

 

[ManhattanProject]

Instead of poking and sharing unwanted gyan.. You could have pointed out where I said I am an expert or I know better than someone here?
If you misread or misquote, that's not my problem.
I stopped responding because I realized people here just assume they know everything better.

and I don't need to learn anything from some random keyboard warrior.

Again, what i wrote all went over your head huh?

 

[Haldilal]

Again, what i wrote all went over your head huh?

Ya'll Nibbiars now you are the most hated person in the Indian defence community. Yesterday many twiteratte were bad mounting you. The @Aditya Ballal saw that tried to defend you but in the last also bad mouthed you.