ADA Tejas (LCA) News and Discussions

[shiphone]

LOL...typical Indian style BS...Again...

J10B has empty weight of 8.9ton, MToW of 19.2 ton for an engine of 80/125kN engine.

8.867 tons is the empty weight of J10/10A, I'm afraid no one is talking about the empty weight of J10B/C, and J10B/C is flying w ith 13.5 ton class engine..

Taihang TVC varient is based on WS-10B which is a 132kN class engine

T J10 is also made of composites to some extent unlike F16 which has 80% aluminum and 10% steel. F16 has empty weight of 8.6 tons and MToW of 19.2 ton for a 80/125kN engine.

The reason why J10 fares poorly in empty weight is because of TVC. Carbon composites have density of 1.8g/cm3 whereas Aluminium has 2.7g/cm3. So, the airframe of J10 should have been lighter by 10% compared to F16 even if 30% composite is used. But, in reality, J10 ends up being heavier than F16. This is the reason

J10 is also a plane made mainly with metal...the lastest varients of the family didn't change this fact essentially although some more composites are applied...

BTW, the WS-10 TVC TD is based on a J-10C

and most importantly, Where is so called LCA mk2? , has it been manufactured? flied? those funny Data on paper means nothing here.

 

[WolfPack86]

I hope by 2018 govt will sanction in building Tejas mk 2 version.

 

[tejas warrior]

I hope by 2018 govt will sanction in building Tejas mk 2 version.

If you look in other way, some of important items are WIP only

- Uttam AESA
- SPJ
- Engine (GE 414 / Kaveri) - I will go with GE414 for first batch at least as 2 have been received by ADA and 4 more will be coming by 2018.
- MK1A will provide much more simpler upgrade path if you consider all those weight reduction.
- ASTRA will be integrated in MK1A by the time MK2 will be in development

What will remain is 1 meter plug and certification.

So, MK2 will be much simpler & quicker to achieve from MK1A.

 

[WolfPack86]

If you look in other way, some of important items are WIP only

- Uttam AESA
- SPJ
- Engine (GE 414 / Kaveri) - I will go with GE414 for first batch at least as 2 have been received by ADA and 4 more will be coming by 2018.
- MK1A will provide much more simpler upgrade path if you consider all those weight reduction.
- ASTRA will be integrated in MK1A by the time MK2 will be in development

What will remain is 1 meter plug and certification.

So, MK2 will be much simpler & quicker to achieve from MK1A.

I heard that lsp 2 is getting ready for intergaration for Uttam aesa radar. Do you know when will kaveri engine will be air worthy.

 

[tejas warrior]

I heard that lsp 2 is getting ready for intergaration for Uttam aesa radar. Do you know when will kaveri engine will be air worthy.

Kaveri is long way.

It will take 10+ years for it getting certified. So, we can think of Kaveri on LCA only after 2025.

So, its not coming in first batch of MK2 also.

IMHO - We will come to know something definite on Kaveri only during 2019 Aero India.

 

[WolfPack86]

Kaveri is long way.

It will take 10+ years for it getting certified. So, we can think of Kaveri on LCA only after 2025.

So, its not coming in first batch of MK2 also.

IMHO - We will come to know something definite on Kaveri only during 2019 Aero India.

So Tejas mk 1a will also have GE414 engine as well as Tejas mk 2.

 

[AMCA]

Interacted with the admin of Tejas Facebook page a month ago and he was saying that work on MkIA has not been started. Any news?

 

[jat]

J10B has empty weight of 8.9ton, MToW of 19.2 ton for an engine of 80/125kN engine.

Tejas MK2 has empty weight of 6.8 ton, MToW of 15.5 ton, 5ton payload with 100kN engine.

The MToW increase of 4 ton and empty weight increase of over 2 tons compared to tejas Mk2 is bad , isn't it? J10 is also made of composites to some extent unlike F16 which has 80% aluminum and 10% steel. F16 has empty weight of 8.6 tons and MToW of 19.2 ton for a 80/125kN engine.

The reason why J10 fares poorly in empty weight is because of TVC. Carbon composites have density of 1.8g/cm3 whereas Aluminium has 2.7g/cm3. So, the airframe of J10 should have been lighter by 10% compared to F16 even if 30% composite is used. But, in reality, J10 ends up being heavier than F16. This is the reason

I don't think India needs to match the weight or payload of the Tejas MK1 with J-10. The j-10 has far heavier engine, a fuel guzzling monster of an engine with a lot of down time. That down time means the J-10 isn't efficient for air patrols or training new pilots. Not exactly wings for new and many pilots want. The same advantage J-10 has over Tejas is the same disadvantage. Tejas for its part, needs to mature, thankfully India did use and get an american engine with great performance.

 

[Babloo Singh]

So Tejas mk 1a will also have GE414 engine as well as Tejas mk 2.

No Tejas Mk1a can't use GE-414 without structural changes to air intake.
Kaveri will get certified with french help much earlier than tejas warrior's estimate of 10+ years..
I guess last 20-40 of 83 Mk1A may fly out with Kaveri..

 

[tejas warrior]

So Tejas mk 1a will also have GE414 engine as well as Tejas mk 2.

No Engine change for Mk1-A.

MK1-A will have GE-404.

 

[tejas warrior]

Interacted with the admin of Tejas Facebook page a month ago and he was saying that work on MkIA has not been started. Any news?

Because, there was not firm order for MK1-A till now. It will happen soon.

However Tenders for AESA & SPJ was opened last year. AESA will be either Elta 2052 OR Thale's RBE2.

 

[ersakthivel]

A couple of points. Broadly agree with your points about canards causing disruption in the laminar flow of air, thus reducing lift- but that is a problem that is very evident only for smaller fighters.

Moreover, a plane that has massive power to weight ratio - like a Rafale or a Su-30MKI can make do with canards, the advantage of achieving high AoAs, and beyond superb instantaneous turn rate makes it more than worthwhile to have canards.

Which is why Su-30MKIs are overkill (as far as manoeuvrability is concerned at any rate). Matlab, excellent power to weight ratio, good energy retention, forward canards, good wing design AND TVC!!!!

Tejas mk2 canards are being contemplated , because of the proposed 1 mtr fuselage plug in gives enough space for extra control surface.

Proper aerodynamic arrangement of canards can be implemented on any plane regardless of TWR or size.

Canards are there from wright brothers days.
. Swedish Viggen too had canards.

 

[ersakthivel]

Mirage had no meaningful canards. The canards are actually small strakes. LCA has cranks instead of strakes and also anhedral delta both of which are lift generators.

Gripen:

Tejas:

As seen above:
1) Canards result in wings being shortened and hence lower wing area compares to length of aircraft which reduces lift. The canards also generate lift to compensate this
2) Canards breaks the airflow in front of the wings, thereby reducing the overall wing's lift.
3) The crank of the Tejas provides lift as well as concentrates vortex under the wing without reducing the wing area. This also doesn't break airflow into the wings nor scatter the wind blowing under the wing.

Canards have a net penalty in terms of lift compared to cranks due to a part of the airflow being scattered away by canards. Cranks are a real jugad way of doing things. There is really no need for canards.

By the way, Naval LCA has LEVCON (etension of wing that acts like canard) to provide additional drag for short landing.

Canards hv their plus & minus in distinct flight envelope areas,


Canard down wash energises vortice airflow on the upper wing ,which aids in low pressure creation & lift.

At the same time there are some force coupling & other issues like the smallee stall angle of canards reducing the main wing from reaching full efficiency in lift.


They would be operated within their deflection limits to over come these issues, by FCS of the plane

 

[ersakthivel]

Canards

The person who uses fake accent to look more intellectual should be avoided, Bharat Karnad just reads some news article from "Actual" defense journalist and reports back with fake accent of his own.

Plz avoid him.

Canards are used to give more lift to jets and they are mostly made up of Aluminium alloy, they are lighter and they hardly cost much, but they have very significant effect on aero data. I always missed Canards on LCA.

Mirage too have small Canards on air-intake.

do hv their issues, deflection will stress front fuselage, weight of actuators move the CG forward on the fuselage ,thus reducing the all important instability margins.

Here 1 mtr extra length of tejas mk2 moves CG further back.

So having canards will compensate it & improve corner velocity performance & reducing la ding distance.

But we will hv to wait & see if canards are going to be simplemente in mk2.

Because it will complicate development timelines

 

[ersakthivel]

Lol, then we wouldn't use Tejas, but more capable fighters with suitable guided weapons.

Btw, english or a translation please. :biggrin2:

What is the capability difference by tejas & other fighters when using long stand off weapons, (excluding brahmins, su 30 mi combo)

 

[ersakthivel]

Su 30 mki's gravity defying performance is mostly due to its

A couple of points. Broadly agree with your points about canards causing disruption in the laminar flow of air, thus reducing lift- but that is a problem that is very evident only for smaller fighters.

Moreover, a plane that has massive power to weight ratio - like a Rafale or a Su-30MKI can make do with canards, the advantage of achieving high AoAs, and beyond superb instantaneous turn rate makes it more than worthwhile to have canards.

Which is why Su-30MKIs are overkill (as far as manoeuvrability is concerned at any rate). Matlab, excellent power to weight ratio, good energy retention, forward canards, good wing design AND TVC!!!!

Excellent full body lift & 3D thrust vectoring

 

[ersakthivel]

It did, because your point was not on illuminating the target in bad weather conditions, but how LCA would fly in that conditions to do a strike:



That's why I answered that it doesn't have to fly low, since the weapon is the key that travels to the target. When you can't guide LGBs with the LDP from the air and no ground illumination is possible either, you uses GPS guidance instead. Most modern LGBs or PGMs offer both, while ATGMs have Mmw guidance seekers too.

So again, no there is no need for LCA to fly low, nor to use dumb bombs if it has the right guided weapons.

Guided Long stand off weapons will run out in the first few weeks of war & will be used on targets of value,

That's why IAF is clinging on to jaguars & weaponized hawk.

After air supremacy is established we need some planes to deliver rockets & tons of low cost dumb bombss from low altitude braving MANPADS.

No escaping the reality.

Even jeddai warriors in star wars need supporting lesser mortal gunmen

 

[Kshithij]

Canards hv their plus & minus in distinct flight envelope areas,


Canard down wash energises vortice airflow on the upper wing ,which aids in low pressure creation & lift.

At the same time there are some force coupling & other issues like the smallee stall angle of canards reducing the main wing from reaching full efficiency in lift.


They would be operated within their deflection limits to over come these issues, by FCS of the plane

Won't 1 metre length increase be compensated by increase in other dimensions as well? Aster all, the ratio is what matters, not merely one dimension. Even wingspan will increase and the weight adjustments and aerodynamic adjustments will be made.

Adding Canards will hamper the size of the wing and increase wing loading. Also, MK2 will have lower length than Gripen E by 1 metre, despite increase in length over MK1 by 1 metre. So, lesser room for canard.

Note, that NLCA has Levcons to assist in landing by increasing drag and hence helping in short landing. The concept of canard is not unknown to ADA but deliberately avoided in LCA and instead focused on cranks.

 

[Sancho]

What is the capability difference by tejas & other fighters when using long stand off weapons, (excluding brahmins, su 30 mi combo)

1) low flight performance
2) limited number of hardpoints
3) external SPJ pod and limited EW
4) limited number of AAMs in strike configs
5) limited range

Those are the problems that will mostly remain, simply by the fact that it's a light class fighter, that never was mean to carry large loads to longer distances. While it can be effective in basic roles, with the right weapons and upgraded flight performance.

That's why IAF is clinging on to jaguars & weaponized hawk.

IAF is clinging to Jags to keep squadron numbers on paper look ok but that's it and HAL/BAE are proposing to arm HTT40 or Hawk, while IAF is desperate for proper fighters.

Air policing
CAS
Reconnaissance

Are roles that fit LCA, while any role with higher threat perceptions, require more capable fighters.

 

[Sancho]

So, MK2 will be much simpler & quicker to achieve from MK1A.

It's the other way around, because MK1A mainly upgrades available systems in the same airframe. For MK2 you need to design and develop a new airframe first, then need to integrate the new systems (engine, avionics and hopefully EW), flight test and certify it.
But then again MK1A, is still dependent on achieving FOC first and that's the real milestone we need to achieve.