LCA TEJAS MK1 & MK1A: News and Discussion

[Bleh]

Guys watch that from this point (timestamped same video);


At least with the sort of turns we have witnessed Tejas do, it would let Mirage a 2 circle fight & 50:50 in one circle... With T/W ratio inferiority of .7 against Tejas's .96, Mirage stands no chance in a scissor.
And the 65kN-95kN thrust of Mirage-2000 would be what F414 powered Tejas would enjoy too. Lol

 

[Emperor Kalki]

Third, as expected from Delta winged aircraft Tejas, it gives good performance in ITR. It means it has greater authority on pointing nose at the target and take a shot. Reason being the delta wings generates higher lift as the AoA goes up. Therefore, the aircraft can sustain pointing it's nose towards the target relatively longer as compared to aircraft with conventional wings. This however comes at a cost of kinetic energy of the aircraft.

Considering that a wvr fight between the two would happen, won't that depend on the merge.....and is ITR really more helpful than STR in a 2 circle fight....?

 

[Bleh]

...and is ITR really more helpful than STR in a 2 circle fight....?

Oh yeah, as long as you got CCM, definitely!.. Especially for the 1st 270° turn when deltas have the advantage.
With modern high offbore CCMs you won't even need to completely face your enemy, thus saving energy for follow-up maneuvers (energy bleeding nose pointing like Flankers can be fatal unless you are 1vs1).

The merge definitely plays a role too.

You can be pushed into a mistake like the above left case... both have same ITR, but the one has lock on other! To exploit the advantage of greater ITR & outturn enemy, you always wanna turn in the direction the bandit was before the merge, like right.

While 1-circle can become a 2-circle+ if you don't get 'em the first turn, but then too Tejas still has an advantage in slow-speed low-energy turning (STR in effect now).

I think that capability to retain performance, is what they try to display here by crazily bleeding energy like this:

 

[piKacHHu]

Considering that a wvr fight between the two would happen, won't that depend on the merge.....and is ITR really more helpful than STR in a 2 circle fight....?

Yes ! At the merge you have 2 options if you are Delta winged fighter; Ignoring use of CCMs
1. Go for one circle fight by anticipating the turning of the bandit and get on its 6'o Clock with superior ITR.
2. Go vertical to build-up potential energy and utilize it later depending up on the move of your adversary.

Now if you get into 2 circle fight, there are potential risks because an aircraft with superior STR will catch you up as you are slowing down due to higher drag of Delta wing.

I think that capability to retain performance, is what they try to display here by crazily bleeding energy like this:

However, it's also true that STR is not everything in air combat. The Soviet school of thought gives supremacy to ITR and super maneuverability. Their tactics dictate forcing overshoot and exploit that window of opportunity by using its superior pitch control by TVC et.al. to get a shot. That's where the venerable Pugachov Cobra and other slow speed maneuvers evolved. Problem with this approach is that it gives too much emphasis on 1-to-1 fight. After pulling a Cobra, you become too slow to become an easy prey for other fighters. Another problem with this approach as you have seen in the DCS video, the dogfight becomes more dependent on pilot's skill rather than the platform.

To counter this, the US doctrine gives emphasis on high speed maneuvers and tighter turning without loosing enough energy. It provides you option to disengage if things are not going well on you side or go vertical. Over and above, the US has better BVRs and superior CCM arsenal i.e. Aim 9x with better sensor and high off-bore sight capability to avoid getting bogged down in "Knife-Fight" like WVR combat where anything could happen.

For Turn-radius part, you can pull it tighter for your benefit in the dog-fight but it's dependent more on the pilot sustaining g-force and the air-frame if it could withstand that much force.

 

[Bleh]

The merge definitely plays a role too.
View attachment 49737

You can be pushed into a mistake like the above left case... both have same ITR, but the one has lock on other! To exploit the advantage of greater ITR & outturn enemy, you always wanna turn in the direction the bandit was before the merge, like right.

This needs a follow-up.

The turning radius is as important as turning rate.
Like here the Mig-35 is displaying greater rate-of-turn (more degrees turned) but the F-16 with lower radius-of-turn & achieves lock. Especially important with LOAL & highoffbore weapons.

Lower airspeed allows less turning circle radius, but turn rate falls too!.. However for Tejas, the low speed maneuverability is good too!

So while high speed it'd try to take advantage of its high instantaneous turn rate again F-16s less min radius...

...but at low speed it will try to take advantage of the low turn radius, where F-16 would turn more sluggishly at wider arc.

While 1-circle can become a 2-circle+ if you don't get 'em the first turn, but then too Tejas still has an advantage in slow-speed low-energy turning (STR in effect now).

Now ^that part between these two is where the Tejas might get into a pickle.

If it fails to achieve a lock in that 1st turn (or its missile misses), then could be at a disadvantageous position W.R.T the F-16, in a multiple turn fight... It has burnt through much of its energy after having 8G turned at 180° to 270°, maybe more than 360° in total, but the F-16 may not have lost enough speed for Tejas to again perform better than it at sustained low speed turn.





That was considering F-16 only, not FC-1. That one is very very weird. I have seen its performance in air show videos it can do really good STR turns, if it has energy, which it doesn't after 1 or 1.5 turns. Then it starts doing max 15°/sec.

 

[Super lca]

According to Pakistanis a formation of sukhois nd mirages raided into sindh yesterday

 

[Chinmoy]

Let's indulge his points for a bit.

We have both F414 rear fuselage & air intake already designed for Mark2. Enough commonality exists for a copy-paste. Same as wing-tip pylons or bulged spine (refering DDR article).
We did prematurely(?) order a bunch of F414 but have not placed any F404 follow on orders, while we dont have more than a dozen in store either. Although we could order in 2021 & still ensure continuous steady supply by mid-2022.
F414 would fit in the fuselage, but will...

1. shift its CG slightly behind (only 50kg weight diff. tho)
2. considerably increase the fuel consumption

...both would create drastic changes in behaviour. Performance & payload will doubtlessly increase, but range may fall below 350km.

That would require the 50cm fuselage plug in front to carry extra fuel, which again takes us back to the same old pre-2015 Mark2 design, that was set aside due to disproportionate drag increase... Or it could rely on new bigger fuel tanks meant for MWF, which it can now carry !


Yeah, I'm so confused right now. But not very convinced.

SFC of GE-F414 is 30% better or should I say less then F404 for the same amount of specific thrust. At cruising altitude and speed, the difference in fuel consumption is 1kg/KnH. So apart from take off and supersonic flight, the fuel consumption rate would not be of a great concern IMO.

Engine of Jet is installed over its Center of Gravity, so yes there would be specific changes internally on the fuselage but not much whatsoever externally. Moreover increasing fuselage length because of increased weight of engine is beyond my understanding. As I mentioned earlier, HAL has specifically mentioned that changing engine from F404 to F414 would not need drastic structural change in Tejas.

Moreover the change of engine would mean a increased MTOW which was always the requirement of IAF from day one for Tejas. They have openly said regarding this for for the specific reason F414 has been considered for Mk2 version.

 

[Bleh]

According to Pakistanis a formation of sukhois nd mirages raided into sindh yesterday

Pakis need something every now & them to keep them from not killing each other.

That was considering F-16 only, not FC-1. That one is very very weird. I have seen its performance in air show videos it can do really good STR turns, if it has energy, which it doesn't after 1 or 1.5 turns. Then it starts doing max 15°/sec.

But speaking of Pakis, their FC-1 I think faces LERX creates high drag that negates the advantages of its smaller conventional wings... While its wide wingspan negates maneuverability advantages of Mig-21's low aspect ratio (science explained below).

I am not sure but that is the only explanation I have been able to come up with for FC-1 performance being inferior to its daddy Mig-21. For reference you may check out Romanians Mig-21s performing at airshows.

SFC of GE-F414 is 30% better or should I say less then F404 for the same amount of specific thrust. At cruising altitude and speed, the difference in fuel consumption is 1kg/KnH. So apart from take off and supersonic flight, the fuel consumption rate would not be of a great concern IMO.

Engine of Jet is installed over its Center of Gravity, so yes there would be specific changes internally on the fuselage but not much whatsoever externally. Moreover increasing fuselage length because of increased weight of engine is beyond my understanding. As I mentioned earlier, HAL has specifically mentioned that changing engine from F404 to F414 would not need drastic structural change in Tejas.

Moreover the change of engine would mean a increased MTOW which was always the requirement of IAF from day one for Tejas. They have openly said regarding this for for the specific reason F414 has been considered for Mk2 version.

I have been thinking about that... and a perfect solution presents itself. I'm not sure how many of you have seen this so I'm posting again.

I once looked into the possibility of airforce version of Tejas NP-2, after picking up chatter that the trainer versions have better area drag values.

This one would be perfect!

HVT told me that this would increase internal fuel capacity by only 100-150kg over present... however if the engine is replaced by a 60 kg heavier one, then would balance out its weight nicely (the drag creating fuselage plug was to fit in more fuel for F414) .
Clean takeoff weight would increase to about 10 tons from 9.8t & the 10kN extra thrust would allow carrying more internal fuel well as well as new bigger tanks, to negate any range penalty.

I still think it's not going to happen. Too drastic, would need new flight testing & modification of control softwares.
But if it would, this is how!.. Maybe on TejEx someday.

 

[Chinmoy]

Just because TEdbf . Orca , mwf are in news recently does not mean nobody thought about these aircrafts back then.
This may be the reason for a bigger order of GE 414 and smaller order of Rafael .

Yeah. 2013, when IAF was playing ping pong with LCA.
2013, when LCA had not even got the IOC.
2013, when ADA was fighting over the weapon package for LCA.
2013, when it was not even sure what IAF would demand next.
At that time HAL signed a deal for nearly 100 engines for some more futuristic project. But they said that these engines would be used in Mk2 variant, which they have now officially termed MWF. Perfectly plausible.

I just hope that HAL doesn't come under hammer now for ordering F404 all over again.

 

[IndianHawk]

No!
He is saying STR is as important as ITR.

Tejas STR he can't reveal as this information may be exploited by our adversary who has great rate turners i.e. F16 or its too bad w.r.t it's peers like Gripen. Anyway, STR charts like those I shared before for F16 are used for development of dogfight tactics.

Third, as expected from Delta winged aircraft Tejas, it gives good performance in ITR. It means it has greater authority on pointing nose at the target and take a shot. Reason being the delta wings generates higher lift as the AoA goes up. Therefore, the aircraft can sustain pointing it's nose towards the target relatively longer as compared to aircraft with conventional wings. This however comes at a cost of kinetic energy of the aircraft.

Check out this video of DCS simulation of M2K vs F16 dogfight.

That's why HV is saying str is not so important for lca.
If lca gets into a dogfight like situation it will rely on itr to gain nose authority. If it fails in that somehow it will back out and return. It's not going to get into multiple looped fight as it doesn't have much endurance to keep doing that and also keep loosing energy.
( Before dog fighter external tanks would be gone ).
On afterburner internal fuel will bleed too fast.

Anyway lca is getting asraam which has the biggest motor among ccm today. So lca will be at very clear advantage in wvr with either China or pakistan jets.
It would try to fire both it's asraam before getting too close and turn back fatser than enemy.

 

[Super lca]

That's why HV is saying str is not so important for lca.
If lca gets into a dogfight like situation it will rely on itr to gain nose authority. If it fails in that somehow it will back out and return. It's not going to get into multiple looped fight as it doesn't have much endurance to keep doing that and also keep loosing energy.
( Before dog fighter external tanks would be gone ).
On afterburner internal fuel will bleed too fast.

Anyway lca is getting asraam which has the biggest motor among ccm today. So lca will be at very clear advantage in wvr with either China or pakistan jets.
It would try to fire both it's asraam before getting too close and turn back fatser than enemy.

Yes delta wing aircraft pilots are specifically trained to use the great itr to their advantage

 

[HariPrasad-1]

Drone swarm control . Unmanned wingman control just like lca sport concept.

Very correct friend.

 

[rohit b3]

If the Tejas & Hornet have the same engine, why is the Tejas underpowered?

Answer (1 of 9): “If the Tejas & Hornet have the same engine, why is the Tejas underpowered?” ANS: Because LCA TEJAS “DESIGN” is a [code ]F——-G[/code] ROCKSTAR.PERIOD. If anyone has ever studied aerodynamics and analysed a group of aircrafts objectively, they will find aerospace designing is gam...

www.quora.com

Interesting answer by Lili Basu Biswas about the Air intakes.
Can someone shed some light on it?

 

[Snowcat]

If the Tejas & Hornet have the same engine, why is the Tejas underpowered?

Answer (1 of 9): “If the Tejas & Hornet have the same engine, why is the Tejas underpowered?” ANS: Because LCA TEJAS “DESIGN” is a [code ]F——-G[/code] ROCKSTAR.PERIOD. If anyone has ever studied aerodynamics and analysed a group of aircrafts objectively, they will find aerospace designing is gam...

www.quora.com

Interesting answer by Lili Basu Biswas about the Air intakes.
Can someone shed some light on it?

A lot of people are actually pointing it out, there is this YouTuber, probably an aero engineer, he talks about that as well.
I think we will see an entirely new design of the intakes with mk2 variant. Probably DSI.

 

[Bhurki]

Spamming from Dhruv thread.

Since Tejas is integrated by HAL, here's a view of their quality control and manufacturing philosophy

The Truth Hurts, Says Indian Navy's 1st Dhruv Flight Commander - Livefist

By Commander YASHODHAN MARATHE (Retd.) I’m a second generation helicopter pilot and have been flying rotary wing machines since 1989. Of course, the primary amount of flying has been on HAL built aircraft, the Chetak and the ALH and of course, the Kiran. I’m quite saddened by the slew of…

www.livefistdefence.com

 

[Bleh]

(Both photos, are edited. Not real)

While Tejas could easily carry 3×droptanks & 1800kg bomb-load, its midboard pylons being limited to 800kg prevent dual-racking 1000lbs bombs like this, as J-10 does... An unfortunate shortcoming of only 100kg.

And whether Tejas can carry tandem 1000lbs on its central pylon is unclear. It could mitigate the above a bit, with inboard droptanks & midboard single bomb... Or 6×1000lb for short-ranged CAS with BVR/WVR missiles.

Spamming from Dhruv thread.

Since Tejas is integrated by HAL, here's a view of their quality control and manufacturing philosophy

The Truth Hurts, Says Indian Navy's 1st Dhruv Flight Commander - Livefist

By Commander YASHODHAN MARATHE (Retd.) I’m a second generation helicopter pilot and have been flying rotary wing machines since 1989. Of course, the primary amount of flying has been on HAL built aircraft, the Chetak and the ALH and of course, the Kiran. I’m quite saddened by the slew of…

www.livefistdefence.com

This is what happens when the parties are not in sync... Such blatant mismanagement & wastage of both time as well as resources! This means ADA, HAL don't even have any liason officer who'd bridge the two organisations.

 

[HariPrasad-1]

Pakis need something every now & them to keep them from not killing each other.


But speaking of Pakis, their FC-1 I think faces LERX creates high drag that negates the advantages of its smaller conventional wings... While its wide wingspan negates maneuverability advantages of Mig-21's low aspect ratio (science explained below).

I am not sure but that is the only explanation I have been able to come up with for FC-1 performance being inferior to its daddy Mig-21. For reference you may check out Romanians Mig-21s performing at airshows.



I have been thinking about that... and a perfect solution presents itself. I'm not sure how many of you have seen this so I'm posting again.

I once looked into the possibility of airforce version of Tejas NP-2, after picking up chatter that the trainer versions have better area drag values.
View attachment 49767
This one would be perfect!

HVT told me that this would increase internal fuel capacity by only 100-150kg over present... however if the engine is replaced by a 60 kg heavier one, then would balance out its weight nicely (the drag creating fuselage plug was to fit in more fuel for F414) .
Clean takeoff weight would increase to about 10 tons from 9.8t & the 10kN extra thrust would allow carrying more internal fuel well as well as new bigger tanks, to negate any range penalty.

I still think it's not going to happen. Too drastic, would need new flight testing & modification of control softwares.
But if it would, this is how!.. Maybe on TejEx someday.

As we all know, multiple Tejas Mk2 were conceived. I was very impressed with first Mk2 design in which a half meter fuselage extension and half a meter longer nosecone was planned. Its plan weight was 6.1 ton with GE 414. Its payload was above 5 tons. We should actually work on this sort of plane to make a better Gripen C/D.

 

[HariPrasad-1]

This needs a follow-up.

The turning radius is as important as turning rate.
Like here the Mig-35 is displaying greater rate-of-turn (more degrees turned) but the F-16 with lower radius-of-turn & achieves lock. Especially important with LOAL & highoffbore weapons.
View attachment 49758
Lower airspeed allows less turning circle radius, but turn rate falls too!.. However for Tejas, the low speed maneuverability is good too!

So while high speed it'd try to take advantage of its high instantaneous turn rate again F-16s less min radius...
View attachment 49759
...but at low speed it will try to take advantage of the low turn radius, where F-16 would turn more sluggishly at wider arc.
View attachment 49760

Now ^that part between these two is where the Tejas might get into a pickle.

If it fails to achieve a lock in that 1st turn (or its missile misses), then could be at a disadvantageous position W.R.T the F-16, in a multiple turn fight... It has burnt through much of its energy after having 8G turned at 180° to 270°, maybe more than 360° in total, but the F-16 may not have lost enough speed for Tejas to again perform better than it at sustained low speed turn.





That was considering F-16 only, not FC-1. That one is very very weird. I have seen its performance in air show videos it can do really good STR turns, if it has energy, which it doesn't after 1 or 1.5 turns. Then it starts doing max 15°/sec.

Highly informative. This is bloody real stuff not very often discussed here.

 

[IndianHawk]

(Both photos, are edited. Not real)

While Tejas could easily carry 3×droptanks & 1800kg bomb-load, its midboard pylons being limited to 800kg prevent dual-racking 1000lbs bombs like this, as J-10 does... An unfortunate shortcoming of only 100kg.
View attachment 49826
And whether Tejas can carry tandem 1000lbs on its central pylon is unclear. It could mitigate the above a bit, with inboard droptanks & midboard single bomb... Or 6×1000lb for short-ranged CAS with BVR/WVR missiles.
View attachment 49827


This is what happens when the parties are not in sync... Such blatant mismanagement & wastage of both time as well as resources! This means ADA, HAL don't even have any liason officer who'd bridge the two organisations.

Carrying bomb on dual pylon creates too much drag. Beside configuration of your first image can be achieved by lca with 2 tandem bombs on each onboard pylon and 800 litre drop tanks on midboard pylon. Range would be same with edited image despite smaller drop tanks as drag would be much lesser.

 

[Karthi]

Carrying bomb on dual pylon creates too much drag. Beside configuration of your first image can be achieved by lca with 2 tandem bombs on each onboard pylon and 800 litre drop tanks on midboard pylon. Range would be same with edited image despite smaller drop tanks as drag would be much lesser.

This is why I want to cancel MK1A , the base version MK1 is very sluggish , the Air Intake limits it's performance . We should go for ORCA and MWF instead. If we using mk1 only point defence then its acceptable