LCA Tejas vs JF-17 Thunder

farhan_9909

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why is lca the least maneuverable fighter of all the 4th generation fighters?

because

*Conventional compound delta design
*such design should use canards.but india didnt opted for canards or france didnt wanted them too
* lack of horizontal stabilizers which reduces the agility
*tailless platforms is a past tense
 

farhan_9909

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TWRs
..................
....
Afaik a good way to calculate the TWR is:

Thrust in kN / G (Earth surface gravitational field strength of 9.807 m/s²)

=> / emptyweight + internal fuel => TWR


With the figures you gave in your comparision of JF 17 and Gripen, it would be like this:

JF 17 B1:

84,5/ 9,8 = 8622

6411+2300 = 8711

8622 / 8711 = 0.99 (rounded to the 2nd digit)


If we take the specs from PAC Kamra site, we have to take 14520lb (6586Kg) emptyweight to account, which changes the results to 0.97 (rounded to the 2nd digit)


Same way for Gripen C:

80,5/ 9,8 = 8214

6800+2270 = 9070

8214 / 9070 = 0.91 (rounded to the 2nd digit)


Short TWR ranking (clean with AB thrust):

1. F16 B52 - 1.11
2. JF 17 B1 - 0.97 to 99
3. LCA Mk1 - 0.96
4. Gripen C - 0.91
5. J10A - 0.88
JFT is only 2nd to EFT in crash ratio.

6 years of active in service and only 1 crash that too due to bird hit.
 

SATISH

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JF 17 has quadruplex fly-by-wire system. But only on 2 axes that is the pitch and yaw axes...

Complete relaxed static stability means the aircraft is unstable in all three axes namely the Pitch, Yaw and Roll. Which means if the Fly-by-wire system fails in even one of the axes the aircraft will crash. So lets say it is more like a brick capable of flight.

http://www.dtic.mil/dtic/tr/fulltext/u2/a200205.pdf

Read this before you actually post something relevant about fly-by-wire



These are the 3 axes of an aircraft.

Hope this will be much helpful for people scratching their head about what these people are talking.
 

ice berg

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why is lca the least maneuverable fighter of all the 4th generation fighters?

because

*Conventional compound delta design
*such design should use canards.but india didnt opted for canards or france didnt wanted them too
* lack of horizontal stabilizers which reduces the agility
*tailless platforms is a past tense
Dude, you are talking to a guy who thinks LCA can bring down the likes of F-22..

Save your breath. :cool2:
 

farhan_9909

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from crobato

A must read.
Some of the highlights on the test pilot article.

"The maneuverability has a profound effect on me. This is one extremely nimble plane". He says when you pull the stick on the J-7, you can only pull it gradually so you can hold the proper angle of attack. The radius of turn is wide and the maneuverability is not good. On the FC-1, if you pull the stick, you can pull all the way in and get a very big instantaneous turn rate. Due to a quad Fly-by-wire, turn rate of this fighter is just remarkable. (something we witnessed in squadron induction ceremony)
Then the Chinese pilot asked PAF pilot how JF-17's maneuverability compares with F-16? PAF pilot said jf-17 maneuvers
better. Then, PAF pilot asked Chinese pilot (who flew F-16 in UK before) the same question, he said they are probably similar. Then, he also said that this maneuverability is just for when it is horizontal and that F-16 is still slightly better for vertical (climb rate) due to superior T/W ratio. Then he talked about the cockpit with the 1 HUD and 3 MFDs. He said that it's like the ones on Gripen and F-18. The MFD gives pilots a really easy interface to work with. each one has 20 buttons to select different information. This allows the pilot to keep his head on flying the aircraft. Then he talked about how China's cockpit and MFD is much further ahead than the Russian ones and the Russians were surprised.

He says or agrees that the FC-1 has superior horizontal maneuverability over the F-16A (maneuvering in the horizontal plane). However due to inferior thrust to weight ratio, the F-16 still has the advantage on the vertical plane.
Avionics are very advanced and pilot workload is easier than any Chinese or even Russian plane at the moment. When compared to the Su-27, the FC-1's horizontal maneuverability easily holds its own, but the vertical maneuverability is inferior than the Flanker. Again thrust to weight ratio is the reason. The FC-1 cannot compare to the Su-27's ultra maneuverability aspects. He explains something here, which is interesting for people to learn. On a mechanically controlled plane like the J-7, you cannot pull the stick all the way through. At transonic speeds, on a delta winged aircraft, the delta can only use a small angle of attack. Once you pull past that limit, you will lose speed, and with it, lift, and the nose of the aircraft goes down. On a fly by wire plane such as the jf-17, you cannot have this problem because the FBW computer processes the inputs and carefully controls the angle of attack.

JFT lacks only a engine with 100kn thrust..would be one hell of maneuverable
 

farhan_9909

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Dude, you are talking to a guy who thinks LCA can bring down the likes of F-22..

Save your breath. :cool2:
Very much

but nothing bad in accepting the fact that LCA has serious design flaws.

in open i accept the flaws in JFT like no dedicated pylon for pod,only 8% of composites,inducted with only wvr capability while now has even carrier killer capabilities.
 

ersakthivel

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Very much

but nothing bad in accepting the fact that LCA has serious design flaws.

in open i accept the flaws in JFT like no dedicated pylon for pod,only 8% of composites,inducted with only wvr capability while now has even carrier killer capabilities.
what is the need for relaxed static stability?

In old fighter designs due to the requirements of good tree top flying to avoid the radar and need to drop the bombs closer to the target,since there were no GPS guided long range stand off weapons, wings were small in width and length.

Because of this most of the weight of the fighter is packed in fuselage making fuselage very heavier with engine fuel in clean config flight.Most of them carried heavy machine guns in the nose and some low weight gravity bombs in the wing to drop close to the target.

Earlier versions of supersonic fighters also carried this wing load out to to avoid it's wing area to be subjected to shock waves out side supersonic cone area.

Because of this fuselage became heavy and as a result of this it's inertia opposed the pilot's desire for quick nose pitching vertical ups and downs.

Only to sort out this problem Relaxed or negative static stability design came into vogue.

This concept essentially means placing the center of gravity behind the center of lift to create a pitch up moment and to avoid the pitch up momentum fighters needed digital FBW which will adjust the control surfaces many times in a second in various combinations.

What counts for the super agility of the relaxed static stability fighters is whether the center of gravity is behind the center of lift . Not whether the center of gravity is above or below the center of lift.

If JF-17 has the above aerodynamic loadout it is a fully relaxed static stability fighter. But unfortunately it looks like the Mig-21 with DSI intakes and LREX in any view.

1. Not 4 axis all digital FBW

2. LREX,

3,DSI,

4. 130 km radar,

5. Carrier killer abilities.


Looking at this picture it clearly shows that the center of the lift is far back, showing it is not a relaxed static stability fighter.

 
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farhan_9909

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what is the need for relaxed static stability?

In old fighter designs due to the requirements of good tree top flying to avoid the radar and need to drop the bombs closer to the target,since there were no GPS guided long range stand off weapons, wings were small in width and length.

Because of this most of the weight of the fighter is packed in fuselage making fuselage very heavier with engine fuel in clean config flight.Most of them carried heavy machine guns in the nose and some low weight gravity bombs in the wing to drop close to the target.

Earlier versions of supersonic fighters also carried this wing load out to to avoid it's wing area to be subjected to shock waves out side supersonic cone area.

Because of this fuselage became heavy and as a result of this it's inertia opposed the pilot's desire for quick nose pitching vertical ups and downs.

Only to sort out this problem Relaxed or negative static stability design came into vogue.

This concept essentially means placing the center of gravity behind the center of lift to create a pitch up moment and to avoid the pitch up momentum fighters needed digital FBW which will adjust the control surfaces many times in a second in various combinations.

What counts for the super agility of the relaxed static stability fighters is whether the center of gravity is behind the center of lift . Not whether the center of gravity is above or below the center of lift.

If JF-17 has the above aerodynamic loadout it is a fully relaxed static stability fighter. But unfortunately it looks like the Mig-21 with DSI intakes and LREX in any view.

1. Not 4 axis all digital FBW

2. LREX,

3,DSI,

4. 130 km radar,

5. Carrier killer abilities.


Looking at this picture it clearly shows that the center of the lift is far back, showing it is not a relaxed static stability fighter.

about the first part i agree..but not answer my question

If JF-17 has the above aerodynamic loadout it is a fully relaxed static stability fighter. But unfortunately it looks like the Mig-21 with DSI intakes and LREX in any view.
meanwhile i will alot about similarities between lca and mig 21 such as both share compound delta wing configuration.
and will post about JFT and MIg 21 in detail tonight.

you tell me on what basis consdering the picture you think JFT is not a unstable fighter?
please post any solid source
since i have found a source claiming otherwise.but will post only when you try to defend your claim.

I agree JFT is not as much unstable fighter as the EFT is..but is similar to F-16 in unstability..will post about my source later.

waiting for your reply why you think considering the above pic as standard as why JFT is not a unstable aircraft..

about jft and mig 21.you are very much deluded.but i wont go enough into this since this is something common with you guys
 

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@ersakthivel,
Can you please tell me what kind of stability do F-16s after Blk-30 have, RSS or Negative or Positive. You answer it correctly and you will never again post this shit about RSS again.
 
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ersakthivel

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@ersakthivel,
Can you please tell me what kind of stability do F-16s after Blk-30 have, RSS or Negative or Positive. You answer it correctly and you will never again post this shit about RSS again.
http://www.eurofighter.com/eurofigh...ctiveness/sustained-turn-rate-supersonic.html

Eurofighter Typhoon has a foreplane/delta configuration which is, by nature, aerodynamically unstable.

The instability of the aircraft is derived from the position of a theoretical "pressure point" on the longitudinal axis of the aircraft. This is calculated from the contribution to lift from each of the aircraft components (the wings, the canards, fuselage etc). If the pressure point is in front of the centre of gravity on the longitudinal axis, the aircraft is aerodynamically unstable and it is impossible for a human to control it.

With the Eurofighter Typhoon, in subsonic flight the pressure point lies in front of the centre of gravity, therefore making the aircraft aerodynamically unstable, and is why Eurofighter Typhoon has such a complex Flight Control System – computers react quicker than a pilot.

When Eurofighter Typhoon crosses into supersonic flight, the pressure point moves behind the centre of gravity, giving a stable aircraft.

The advantages of an intentionally unstable design over that of a stable arrangement include greater agility – particularly at subsonic speeds - reduced drag, and an overall increase in lift (also enhancing STOL performance).
Whatever You and I say about relaxed static stability , the above passage is what the design team of Eurofighter thinks about RSS.


Generally high wing loading fighters have better sustained turn radius, Is that right ?

The F-15 has an instantaneous [turn rate] of 21 [degrees] and a sustained [turn rate] of about 17 degs at corner speeds of 350 knots degrees. At speeds of 200 knots it has around 21 deg per sec sustained turn rate.

Only at low speeds of below 200 knots F-15 has 21 deg sustained rate.

. Is this right?

It is no world beating performance.

The repeatedly sold shit(as you describe the RSS) F-16 can do much better STR than conventional stable non FBW design and also without this so called RSS F-15

Do you agree or not? .

Why this kolaveri about me not posting in this forum again??
 
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ersakthivel

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about the first part i agree..but not answer my question



meanwhile i will alot about similarities between lca and mig 21 such as both share compound delta wing configuration.
and will post about JFT and MIg 21 in detail tonight.

you tell me on what basis consdering the picture you think JFT is not a unstable fighter?
please post any solid source
since i have found a source claiming otherwise.but will post only when you try to defend your claim.

I agree JFT is not as much unstable fighter as the EFT is..but is similar to F-16 in unstability..will post about my source later.

waiting for your reply why you think considering the above pic as standard as why JFT is not a unstable aircraft..

about jft and mig 21.you are very much deluded.but i wont go enough into this since this is something common with you guys
It is your responsibility to post with authentic source that JF-17 was designed as a fully relaxed static stability fighter . Not mine.

ANy credible source for it's similar unstability as F-16?

Which Mig-21 has compound delta wing form????????????????



http://www.eurofighter.com/eurofigh...ctiveness/sustained-turn-rate-supersonic.html

Eurofighter Typhoon has a foreplane/delta configuration which is, by nature, aerodynamically unstable.

The instability of the aircraft is derived from the position of a theoretical "pressure point" on the longitudinal axis of the aircraft. This is calculated from the contribution to lift from each of the aircraft components (the wings, the canards, fuselage etc). If the pressure point is in front of the centre of gravity on the longitudinal axis, the aircraft is aerodynamically unstable and it is impossible for a human to control it.

With the Eurofighter Typhoon, in subsonic flight the pressure point lies in front of the centre of gravity, therefore making the aircraft aerodynamically unstable, and is why Eurofighter Typhoon has such a complex Flight Control System – computers react quicker than a pilot.

When Eurofighter Typhoon crosses into supersonic flight, the pressure point moves behind the centre of gravity, giving a stable aircraft.

The advantages of an intentionally unstable design over that of a stable arrangement include greater agility – particularly at subsonic speeds - reduced drag, and an overall increase in lift (also enhancing STOL performance).
If your JF-17 too has the same aerodynamic load out of the TYPHOON like center of flight shifting in front of center of gravity in subsonic flight , it is a Relaxed static stability fighter. If you have any credible link for that , please post. then I will have no qualms about agreeing that JF-17 is an RSS fighter.
 
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farhan_9909

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It is your responsibility to post with authentic source that JF-17 was designed as a fully relaxed static stability fighter . Not mine.

ANy credible source for it's similar unstability as F-16?

Which Mig-21 has compound delta wing form????????????????
well i guess i had posted this in the past as wel let me post it again

NOTE:Xialong 4 means the 4th prototype of JFT,..

onwards pt-04 JFT was extensively modified into a complete RSS.

crobato
Its quite some dense reading, at least the author tries to make some effort on it. Feng pretty much said it all, much of the stuff appears gleamed online, then given analysis and summary. IMO, the first part of the article seems a more interesting before he drifted to the range, radar, avionics and engine issues. Here is a google translation on his comments on the aerodynamics. Its a long analysis though to explain the obvious, the expanded LERX allows the plane to maneuver at higher angles of attack. Also he is correct in the observation that the LERX and the DSI adds to the negative stability of the plane (will make the plane pitch up automatically requiring an FBW needed to keep the nose down in oscillating movement). The LERX will move the center of lift forward, while the weigh reductions in the front as a result of the DSI implementation will move the center of gravity backward. Hence this also improves the plane's maneuverbility.


According to the information obtained by the author, with surfers and explore! 1. 1 configuration. side of Xiaolong 04 and 16 similar to the configuration, Medium used pneumatic normal aspect ratio wing edge of the layout, highlighted the strong performance of low-altitude and high-subsonic mobility. But in the details, the two were different, Xiaolong 04 : First, the edge of the area and more than 01 planes. also much higher than the F-16. Aircraft wings are designed to improve the edge of the lift-to-drag ratio under a certain angle of attack, improving the performance of the aircraft at high angles of attack. But using such a large edge design of the aircraft is not, it is estimated that only a F-18E/F. Trouble from the edge of the 5.2 m 2 to 7 m 2, increased by 34%. It will not only raise the maximum lift coefficient aircraft, taking off and landing capabilities. also greatly enhanced the mobility of the aircraft at high angles of attack. extremely powerful vortex edge of the wing airflow postpone the occurrence and development. F-18E/F excellent performance at high angles of attack apparently inseparable from its side of the wing design. Meanwhile, behind the Xiaolong 04 / end up greatly, bow torque at high angles of attack can provide. Xiaolong 04 while increasing the use of its high angle of attack expected to further enhance mobility! But more important role is that of Xiaolong 04 will be significantly increased while the focus of aerodynamic brought forward. We know that while the focus of the aircraft is located, Lift edge of the vortex caused by the contribution of the wing while washing aerodynamic flow will significantly toward the center. Therefore side of the aircraft configuration is usually static longitudinal instability, active control technology needed to be addressed. For example, the F-16 is a typical "relaxed static stability" with the conventional design : layout, F-16 wings moved forward by 40.6 centimeters, so aerodynamic center forward. M0.9 at its static stability in slightly negative, and 8% at M1.2. Aerodynamic focus toward growing cause of the border, Xiaolong 04 will be the focus might change (after I speculated that it might be a slight shift : DSI weight because the more obvious the former fuselage, Yields rear edge of the electronic module will be partially offset by the increased weight and nose). Aerodynamic focus light Xiaolong 04, the focus changes I guess Xiaolong 04 earlier in the static stability will be further relaxed. And the use of "the entire longitudinal flight control authority fax + 40 degrees more than two simulated redundancy backup" system will be fully satisfy the static stability After the relaxation of control! Xiaolong 04 relaxed static stability will not only further enhance their mobility, More importantly, will be greatly reduced in the span of supersonic trim resistance and help span performance of the supersonic, DSI combination of the weight and the weight of the whole growth pushed down, The greatest number may be more than 04 M M1.6 the biggest increase in the original design! Of course, increasing the edge of the edge of the vortex induced intensity can also lead to larger aircraft pitch moment of non-linear problems, Early mechanical-hydraulic control system's apparent inability to solve, but a good example of Xiaolong 04 flight control solution! 2. Details from the wing of the main wings, Xiaolong 04 and F-16 are different, Xiaolong 04 wing leading-edge sweep angle of 42 °, composite wing bending and torsion, and the latter leading edge sweep angle of 40 °. Aspect ratio of about 3.0, both front and rear wing. F-16 wing no reverse! Contrast can see that Xiaolong 04 of the wing leading edge sweep angle greater aspect ratio smaller than the root shoot, Airfoil closer delta, in a large range of airfoil stall characteristics, and inter-and supersonic flight resistance small! Is likely to be absorbing the essence of the Russian type pneumatic three generations! Even more noteworthy is that Xiaolong 04 in a front flap with the same strain J-10 on the basis of bending and torsion using a composite wing design No composite wing bending and torsion and 16. Why? Design, I believe that this may be related to Xiaolong 04 delta is closer to the airfoil, delta is the biggest drawback of induced resistance, easy airflow vortex formation, loss of front lift. With the front flap and using composite reversed, can improve the overall speed of the largest lift-to-drag ratio. India's LCA has a similar design, I see in inspection data on the Indian side in the LCA had explained his comments : He said the purpose of this design is used to improve the characteristics of wing lift, as he thought the wing dihedral angles of attack. first stall at high angles of attack, time pressure center moves, bow torque produced, and yet Winglet stall. Therefore horizontal control. That the design can be used to enhance the lateral stability of aircraft at high angles of attack. As we all know, single Yields Yields larger aircraft to fly at high angles of attack is the reason, Yields will be shielded fuselage turbulence lose lateral stability, thereby restricting the mobility single Yields aircraft at high angles of attack. If the speculation is true, then the combined side of the design Xiaolong 04 will increase their ability to fly at high angles of attack. able to its excellent maneuverability at high angles of attack! Gen will bring slightly smaller than Winglet flutter, usually cut with a sharp or heavy objects to be resolved Xiaolong Winglet whose every missile in flight test of time with this estimate, and the increase in the electronic module Yields dropped after a sharp cut. While it can be resolved flutter, but feel a bit uncomfortable in the number of visual!
Last edited by crobato; 02-27-2007
 

ersakthivel

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well i guess i had posted this in the past as wel let me post it again

NOTE:Xialong 4 means the 4th prototype of JFT,..

onwards pt-04 JFT was extensively modified into a complete RSS.

crobato
i asked for a credible link.Not a write up by some one.

Following the third prototype, several design changes and improvements were developed and incorporated into aircraft from this point. Due to excessive smoke emissions by the RD-93 engine the air intakes were widened, reported control problems exposed in testing resulted in wing leading edge root extensions (LERX) alterations.
The mid-mounted wings are of cropped-delta planform. Near the wing root are the LERX, which generate a vortex that has the effect of providing more lift to the wing at high angles of attack encountered during combat manoeuvres. A conventional tri-plane empennage arrangement is incorporated, with all-moving stabilators, single vertical stabiliser and rudder, as well as twin ventral fins. The flight control surfaces are operated by a computerised flight control system (FCS), which also adjusts the slats/flaps for improved manoeuvring. Up to 3,629 kg (8,000 lb) of ordnance, equipment and fuel can be mounted under the hardpoints, two of which are on the wing-tips, four under the wings and one under the fuselage.[20]
The aircraft has a composite FCS consisting of conventional controls with stability augmentation in the yaw and roll axis and a digital fly-by-wire (FBW) system in the pitch axis. The leading edge slats/flaps and trailing edge flaps are adjusted by the FCS automatically during manoeuvring to increase turning performance.[20] Some sources state that the system has been upgraded to provide fly-by-wire flight control in the roll and yaw axis also, the serial production aircraft having a digital quadruplex (quad-redundant) FBW system in the pitch axis and duplex (dual-redundant) FBW system in the roll and yaw axis.[52]
The above is what wiki says about the reason for LREX, not for implementing Relaxed static stability.
 
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farhan_9909

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After extensive search..i got the post of crobato confirming that JFT is a unstable design.credits goes to antibody.
will post the as soon as antibody sends me the link to the original crobato post

Meanwhile posting the Antibody post


So i was right..jft was extensively modified :D

i was just reading a forum where they say jft is a conventional 3rd gen. stable design :frusty:

Negative static stability

The F-16 was the first production fighter aircraft intentionally designed to be slightly aerodynamically unstable.[43] This technique, called "relaxed static stability" (RSS), was incorporated to further enhance the aircraft's maneuver performance. Most aircraft are designed with positive static stability, which induces an aircraft to return to its original attitude following a disturbance. This hampers maneuverability, as the tendency to remain in its current attitude opposes the pilot's effort to maneuver; on the other hand, an aircraft with negative static stability will, in the absence of control input, readily deviate from level and controlled flight. Therefore, an aircraft with negative static stability will be more maneuverable than one that is positively stable. When supersonic, a negatively stable aircraft actually exhibits a more positive-trending (and in the F-16's case, a net positive) static stability due to aerodynamic forces shifting aft between subsonic and supersonic flight. At subsonic speeds the fighter is constantly on the verge of going out of control




crobato 's post in 2008
The JF-17 is indeed unstable in the pitch axis. When the first ever prototype was introduced, its flight control system was FBW on the pitch control, but retained manual on the roll axis. Later prototypes switched to FBW on the roll axis.

If the plane has pitch axis FBW from the start, its a good reason and a very high probability it has negative static instability. More so in the later versions because the redesigned LERX and DSI can cause such changes. The DSI may not be as sophisticated as the JSF's but certainly a lot more than conventional fixed and variable intakes you can find in aircraft today.


I remember the designers of the JF-17, also the designers for the J-10, comment that the JF-17 is unstable and therefore required FBW, through an interview years ago.


You won't find anywhere in the world where a fighter that features LERX---which tends to adjusts the center of lift forward---and has advertised FBW yet to be somehow statically stable in pitch


Source: http://www.-----------/forums/jf-17...ole-fighter-thread-4-a-193.html#ixzz2S2Yui73o
 

farhan_9909

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i asked for a credible link.



The above is what wiki says about the reason for LREX, not for implementing Relaxed static stability.
IF it is not mentioned it doesnt mean this was not done..

will post the link to crobato soon
 

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@ersakthivel, I have not stopped you or even suggested that you stop posting. My post was only w.r.t RSS.
F-16 blk-30 onwards are stable FBW designs fyi. But they retain not just original perf but have it even better now wherein the stability margins have been reduced to less than 3% and that gives far better handling to F-16s now even though the ac is far more heavier than the earlier models.

The maneuoverability of an ac is a direct function of its longitudinal stability margin. If you keep it between 1-5% of C of G ac will have very high agility. This margin is applicable even for RSS ac. An RSS ac which has stability margins set beyond 5% behind C of G for negative stability will have SAME amount of problem in REDUCING pitch up which a positively stable ac with similar positive stability margins will have in INCREASING pitch up.
Use of thrustline to overcome this control effectiveness requirment in a positivly stable ac has many benefits and I have used it in my design to provide better pitch up rates than an RSS ac while the ac remains positively stable thru out its flight envelope and also to have very low approach speeds. Basically to get same benefits as that of RSS in a positively stable ac.
 
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ersakthivel

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After extensive search..i got the post of crobato confirming that JFT is a unstable design.credits goes to antibody.
will post the as soon as antibody sends me the link to the original crobato post

Meanwhile posting the Antibody post


So i was right..jft was extensively modified :D
crobato's post assumes that lrex and DSI has made it RSS,

And since pitch axis FBW is there it must be RSS, all assumptions,

But the wiki says to overcome control issues the Lrex was added, which is correct because the old Mig-21 models had big handling problems at take off and landing ,
leading to many crashes.TO CORRECT THIS CONTROL PROBLEM lrex WAS ADDED IS WHAT wiki SAYS.
A credible link from the JF-17 manufacturer saying so is what I wanted.
 

farhan_9909

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crobato's post assumes that lrex and DSI has made it RSS,

And since pitch axis FBW is there it must be RSS, all assumptions,

But the wiki says to overcome control issues the Lrex was added, which is correct because the old Mig-21 models had big handling problems at take off and landing ,
leading to many crashes.TO CORRECT THIS CONTROL PROBLEM lrex WAS ADDED IS WHAT wiki SAYS.
A credible link from the JF-17 manufacturer saying so is what I wanted.
so you still believe JFT is a mig 21?

please say yes or no...since i wont waste my time here further than

Even after proving that LCA has alot of design flaws and will remain only a advance trainer and a technology demonstrator considering its design limitation..
 

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JF 17 is so good fighter plane that PLAAF dont want it, in LCA case IAF dont want it either, they want fighter that can go for plus they have SU 30 MKI in numbers and MRCA in future.
 

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