LCA TEJAS MK-I & MK-IA: News and Discussion

[BON PLAN]

If you can read, I have mentioned earlier that beyond 2nd generation jets, most of fighter jets are unstable design.

You are a certified dumb who claimed Mig-29 a unstable design. Learn some mathematics dumb

Not a question of math.

 

[Satish Sharma Ji]

Mirage III can sustain inverted flight. It is a stable design.
THAT PROVE NOTHING.

Well read my previous response.
There i clearly mentioned what is stable what is unstable and what is neutral stability. Which is responsible for sustained inverted Flight or to sustain any role, pitch action of Mirage 3, f15 and all other. Don't debate with him he say all post 2nd generation aircraft are unstable designs.

 

[Vishnugupt]

Not a question of math.

Now I can understand your problem. Leave it.

Well read my previous response.
There i clearly mentioned what is stable what is unstable and what is neutral stability. Which is responsible for sustained inverted Flight or to sustain any role, pitch action of Mirage 3, f15 and all other. Don't debate with him he say all post 2nd generation aircraft are unstable designs.

Do you even know how aircraft generation designated??

First generation - Subsonic
Second generation - Speed > 1 Mac
Third generation - Maneuverability
Fourth generation - Avionics and BVR
Fifth generation - Stealth

Achieving Maneuverability is impossible without applying a degree of instability in the design.

I have told you, don't go retard like Akim and @BON PLAN

Stop watching American documentary/Reddit which claims you can't control unstable design without FBW.

 

[Vishnugupt]

F15 is a stable fighter. And one of the best even those days.

REDACTED, it is called relax Stability, not a stable design.

Please spare us from your knowledge.

@Vishnugupt - Please behave, avoid use of foul words

 

[NerVik]

This thread is getting a little too aggressive, no? Beginning to get slightly off putting with all the cuss words and unnecessary aggression. Anyone else feel that or is it only me?

 

[Vishnugupt]

This thread is getting a little too aggressive, no? Beginning to get slightly off putting with all the cuss words and unnecessary aggression. Anyone else feel that or is it only me?

@BON PLAN messaged me abuses words privately. He can't defend his claim here so using as usual Western technique.

 

[Azaad]

This thread is getting a little too aggressive, no? Beginning to get slightly off putting with all the cuss words and unnecessary aggression. Anyone else feel that or is it only me?

Weren't you present on DFI? No wonder you're uncomfortable. All DFI ians & by extension DFB ians undergo such rites of passage. It's baptism by fire. That's how most members here display their affection for other members. It's a perfectly normal day at DFB.

 

[saturatedfat]

This thread is getting a little too aggressive, no? Beginning to get slightly off putting with all the cuss words and unnecessary aggression. Anyone else feel that or is it only

True,
Even in the sukhoi 30 mki forum same thing happened

 

[NerVik]

Weren't you present on DFI? No wonder you're uncomfortable. All DFI ians & by extension DFB ians undergo such rites of passage. It's baptism by fire. That's how most members here display their affection for other members. It's a perfectly normal day at DFB.

@BON PLAN messaged me abuses words privately. He can't defend his claim here so using as usual Western technique.

I wasnt on DFI officially unfortunately, by the time I registered the server was down and eventually DFI closed. I know how DFI'ians show love but What seemed different this time was a seemingly one sided aggression from Vishnu, until he just pointed it out now that BobPlan privately abused him. Now I understand Vishnu's aggression. Still, I hope thread gets less heated.

 

[Pundit Pikachu]

Why not,
But why ordering a F404 powered jet when you already have a F414 one (ie not in a very different league).
Better ask SAAB to create a low end Gripen E, with a weaker but more affordable weapon system, and a derated engine for more durability.

Because It's a great Deal

 

[Satish Sharma Ji]

Now I can understand your problem. Leave it.



Do you even know how aircraft generation designated??
First generation - Subsonic

Second generation - Speed > 1 Mac

Third generation - Maneuverability
Fourth generation - Avionics and BVR
Fifth generation - Stealth

Achieving Maneuverability is impossible without applying a degree of instability in the design.

I have told you, don't go retard like Akim and @BON PLAN

Who asked u generations. I have already debunked you. Did u find only this comment of mine to reply u could have replied to previous one where I debunked your bs.

You're where the one who said mig29 is a unstable design no it isn't it has neutral
Stability.
You're confusing yourself with neutral stability and a aerodynamics character called instability.
Mig isn't a unstable design and unstable design and relaxed static stability are almost same thing.

While yeah some aircrafts have -ve static stability meaning this would help in pitch

As I have f4 example in my previous comment it was +ve longitudinally stable so it's horizontal stabilizer in idel flight position were kept such that they would develope dowforce to balance +ve stability.

This kind of thing is seen in many 3rd generation fighters but this isn't unstable design it could -ve,neutral, +ve. However +ve longitudinally stability doesn't have benefit.
So this doesn't need fbw.
And f15 doesn't have RSS.

This isnt always put in aircraft for muneuverability some designs are this way like f4. While mig 29 is no where near unstable in pitch it is very slightly +ve longitudinally stable almost neutral. This has no benefits like a unstable design would have. And also it isn't unstable in roll too. Let alone pitch

So its not a unstable design.

Stop watching American documentary/Reddit which claims you can't control unstable design without FBW.

Now u listen carefully some aircrafts do have the design you're claiming to be unstable which is neutral Static stability and not a relaxed static stability or intentional instability.

This are different thing you were saying mig can fly sustained inverted so it's unstable which is bs..

What you're claiming to be unstable is or could be neutral static stability. Or longitudinal static stability or directional static stability

Neutral airplane stability' describes a situation where it will deviate from what it was doing when the aircraft is disturbed. However, when the disturbance is removed, the aircraft will stay in the new state caused by the disturbance.
And this isnt inherent instability which we are talking abt
A statically neutral aircraft can induce dynamic instability which is basically tendency to remain.... ( Above neutral stability definition)
Dont get confused between this.
Accept you were wrong here.

Muh miga 29 is unstabal dezain

 

[125mm_Smoothbore]

Why not,
But why ordering a F404 powered jet when you already have a F414 one (ie not in a very different league).
Better ask SAAB to create a low end Gripen E, with a weaker but more affordable weapon system, and a derated engine for more durability.

Well around 180 mk1a would cost 12-13 billion dollar (48k crore+ 63k crore)
I can bet 100 modded gripen e would cost anywhere near 20 billion mark

 

[Satish Sharma Ji]

Not a question of math.

No sir you need mathematics to understand basic theoretical aerodynamics.
Otherwise u will be declared another akim lol.

 

[Satish Sharma Ji]

Because It's a great Deal
View attachment 9647

I can't edit so just visualise Angry
Uncle sam with ge f404 engine on shoulders.

 

[londonparistokyo]

How is any of this relevant to LCA?

 

[Satish Sharma Ji]

Chutiya, it is called relax Stability, not a stable design.

Please spare us from your knowledge.

Please u spares us from you're knowledge

F15 was not a relaxed static stability design. Relaxed stability is same as unstable design or intentional instability.

Old fighter aircrafts had slight positive static stability close to zero or neutral static stability because of this they can sustain there maneuvers even after control surfaces are brought to ideal.
(Basically flying sustained inverted after disturbance (control surfaces is brought back to ideal)in you're language)
Which means they are not a stable design but also they are not intentionally unstable.


Now neutral stability induces slight instability which is manageable by slightly moving its stability to +ve. F15 & mig29 have slight positive static stability close to neutral stability. Where best combination is gotten. For non fbw aircraft. This doesn't help in muneuvering this can just sustain the last external change and will not get stabilised in levelled flight that's it. Neutral static stability induces slight dynamic instability (which I explained)
This slight instability is not relaxed static stability.

Positive stability means a stable design it will return to levelled flight after external disturbance. So that's why old jets have slight +ve but almost neutral stability. Which is why they sustain the external disturbance and dont return to levelled flight which is what needed in muneuvering. So this combination doesn't need fbw.
And having true +ve static stability is of no use as it would stabilise the aircraft.
+Ve static stability induces dynamic stability

Keeping complete neutral stability would might need fbw but if fbw is put in a aircraft then -ve stability is desired to exploit maximum munuvering.

-ve stabilizer is same as neutral stability but instead of maintaining/sustaining the same attitude after external disturbances it keep on increasing in amplitude without much of use of control surfaces. -ve stability induces dynamic instability.
So with a bit of external disturbance the -ve stability design would not stop banking even after external disturbance is removed this seems impossible to be managed by human so fbw is behind the controlled use. With slight control surfaces input without facing much of drag the aircraft can munuever at angles where a stable design would require alot of control surfaces action increasing drag reducing energy.
This is the feature called intentional Instability which is found in f16, Tejas f22, all kind of relaxed static designs.

The close to neutral stability design induce slight instability but it's sustained after control surfaces is brought to ideal it doesn't keep increasing at rate like in -ve stability.
If aircrafts is inverted it will remain as it is .
While in -ve stability even the slight increase in pitch would result in increasing the pitch at a very high rate even after control surfaces are brought to ideal. That's why fbw is there. This behaviour is limited with fbw.
This is relaxed static stability. Or a unstable design.
I had explained in my previous to previous response f16 has com behind centre of lift. Which causes it to -ve static stability. So with just slight horizontal stabilizer input It can pitch up very high. This is intentional instability for pitch, f16 wings design made it neutral in roll (not Unstable). So it could also sustain a inverted flight or remain to
continue in the same motions following a disturbance, neither increasing nor decreasing(unlike -ve), causing the aircraft to maintain constant deviation from its initial position.

Also f16 looses it instability as soon as it passes mach 0.8
Speed has role in stability as centre of lift shifts.

While +ve static stability doesn't help in such muneuvering f4 had which was countered balanced by horizontal stabilizer which generated dowforce in ideal to flight straight.
This aircrafts had quite high +ve static stability.

 

[Satish Sharma Ji]

Weren't you present on DFI? No wonder you're uncomfortable. All DFI ians & by extension DFB ians undergo such rites of passage. It's baptism by fire. That's how most members here display their affection for other members. It's a perfectly normal day at DFB.

Im actually holding back I was banned on dfi once, otherwise.......

 

[SKC]

You say that you have no experience of selling fighters (I imagine that is what you mean) but India has tried selling Tejas to a number of countries. If what you are saying is that HAL marketing and salesmanship is below par, how about getting some people in who know what they are doing? If there are incompetents at HAL, let them go and be incompetent in another company.

You statement contradicts your own points:
India tried few times but so far, no sales anywhere. I am not sure even if entered any countries program officially. Most of the time it is just the Defense fans putting news that we are in forefront of any purchase program. Could be we officially entered the Malaysian purchase plan, but I am not 100% sure.

Similarly, IT WAS BEING SAID we entered the Egypt's fighter plane purchase plan but again I don't see any reality to that.

........ If there are incompetents at HAL, let them go and be incompetent in another company....

Go where? and who is going to let them go in first place? This is not buying or selling fish n chips in your near by restaurant. It is the premier agency responsible to build the planes.

 

[SKC]

@BON PLAN messaged me abuses words privately. He can't defend his claim here so using as usual Western technique.

Report such case to Admins/Mods instead of using Foul words on threads.

 

[Spitfire IX]

You statement contradicts your own points:
India tried few times but so far, no sales anywhere. I am not sure even if entered any countries program officially. Most of the time it is just the Defense fans putting news that we are in forefront of any purchase program. Could be we officially entered the Malaysian purchase plan, but I am not 100% sure.

Similarly, IT WAS BEING SAID we entered the Egypt's fighter plane purchase plan but again I don't see any reality to that.



Go where? and who is going to let them go in first place? This is not buying or selling fish n chips in your near by restaurant. It is the premier agency responsible to build the planes.

So the premier agency responsible to build the planes should retain any incompetents because nobody else would want them. Not so premier thinking!