LCA TEJAS MK1 & MK1A: News and Discussion

Trololo

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Limited range and space for avionics and upgrade. Thrust issue and wvr fight capability and aerodynamics need to be refined.

It has good BVR capability though with BVR Derby and ASRAAM and Elta 2052
Mk1 and Mk1A will be point defence fighters. They will not be mandated to cross borders. Once MWF comes into the scene they will be posted in bases deeper in the hinterland rather than those closer to the border. But yes they will provide good BVR capability as well as CAS capability once enemy airspace is cleared. One thing to note is if SFDR is mounted on the Mk1As then with AWACS support A pack of 4 Mk1As will be able to shoot 16 SFDRs towards an incoming OPFOR package. And that is a very good thing indeed.
 

Vilander

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Limited range and space for avionics and upgrade. Thrust issue and wvr fight capability and aerodynamics need to be refined.

It has good BVR capability though with BVR Derby and ASRAAM and Elta 2052
Just curious why is aerodynamics an issue when ada must have taken a good while to design this with all state of art process in play. Just wondering why it’s still an issue what constraints must have lead to it ?
 

mist_consecutive

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View attachment 62129
a bit unrelated but this pic was posted few pages back, the gun hasn't been mounted tho HAL is ready after IAF demands.
What outstanding incompetence :doh: They literally cut an aluminium sheet with a cutter and riveted it below. The sheer crudeness of the structural design makes me bang my head:frusty:

The crudeness of the build of the area speaks volumes... It's still in prototypic state.
This better be just a demo-example made in haste. What kind of 8th class fail engineers work in HAL?
 

Flying Dagger

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Mk1 and Mk1A will be point defence fighters. They will not be mandated to cross borders. Once MWF comes into the scene they will be posted in bases deeper in the hinterland rather than those closer to the border. But yes they will provide good BVR capability as well as CAS capability once enemy airspace is cleared. One thing to note is if SFDR is mounted on the Mk1As then with AWACS support A pack of 4 Mk1As will be able to shoot 16 SFDRs towards an incoming OPFOR package. And that is a very good thing indeed.
Ok 😂😂😂😂

Just curious why is aerodynamics an issue when ada must have taken a good while to design this with all state of art process in play. Just wondering why it’s still an issue what constraints must have lead to it ?
What is state of art you are referring to please provide details. 🙂
 

Flying Dagger

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What outstanding incompetence :doh: They literally cut an aluminium sheet with a cutter and riveted it below. The sheer crudeness of the structural design makes me bang my head:frusty:


This better be just a demo-example made in haste. What kind of 8th class fail engineers work in HAL?
There are lot of engineer working there with marksheet forged through private south indian colleges. Specially the interns. 😂
 

fire starter

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By last August, HAL’s Aircraft Research & Design Centre (ARDC) as the lead design authority had completed the structural design of the Tejas Mk.1A. The provisional set of drawings has also since been released for inspection & approval by IAF HQ & CEMILAC. These include those for new airframe-mounted panels to reduce the DI (daily inspection) time. In addition, a new concept called panel-in-panel (derived from the Rafale’s design) will be incorporated to increase the visibility of the components during DI time. Additional systems design activities are currently underway, like cockpit configuration & environment control system (ECS). By February 2021, all the selected imported hardware will start arriving for systems integration. By then, the final systems design is also expected to be completed. This will be followed by series of rig tests of all individual pieces of hardware (like the Unified Electronic Warfare Suite or UEWS, Digital Moving Map Display with 2-D maps & 3-D perspective view, provision for Indian Regional Navigation Satellite System/IRNSS-based navigation positioning system, GAGAN or GPS Aided Geo Augmented Navigation and SBAS or Satellite-based Augmentation System) to ensure compatibility with the ECS, electrical power supplies, MIL-STD-1553B & MIL-STD-1760 databus interfaces, and EMI-shielding. Up to 200 flight tests to be conducted by two LSP-series platforms from mid-2022. Final operational configuration of Tejas Mk.1A will be ready by late 2023. Metal-cutting is expected to commence one year after contract signature (of 73 single-seaters & 10 tandem-seaters) and first flight of the first SP-series Tejas Mk.1A (SP-41) is expected during the last quarter of 2023.

-PKS
 

Dessert Storm

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Just curious why is aerodynamics an issue when ada must have taken a good while to design this with all state of art process in play. Just wondering why it’s still an issue what constraints must have lead to it ?
Maybe because it was an attempt, a long time after Marut, on designing a fighter. They would have wanted to get the max out of a simple design (you see the canards in MK2 now), without too many control surfaces. This would make the control laws 'relatively' simple to write, test, refine and at the same time make the design less likely to fail. All this might have resulted in a compromise on aerodynamics (F 35 ain't too nimble either, dosen't mean it's bad).
 

ersakthivel

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I just wonder from where people get these ideas from,,,,,

"Mk1 and Mk1A will be point defence fighters. They will not be mandated to cross borders. Once MWF comes into the scene they will be posted in bases deeper in the hinterland rather than those closer to the border "

"Limited range and space for avionics and upgrade. Thrust issue and wvr fight capability and aerodynamics need to be refined. "

just read the following piece , which rebuts such fiction based claims,


"For the purposes of the same, we will compare the Tejas Mk1 (40 on order, with 17 delivered) and Mk1A (83 units to be ordered soon) with the Gripen C/D and the F-16 IN. It should be noted that the Gripen E/F will not be available before 2023 at the earliest. By that time, India’s Medium Weight Fighter (MWF) or Tejas Mk2 is expected to take to the skies and will be comparable to the Gripen E/F in just about every aspect. "

Thats the reason for just 83 tejas mk1A orders,

IAF expects MK2 by the end of 83 tejas mk1A order completion.



"The endurance of an aircraft is determined by four primary factors, the fuel fraction, the lift-to drag ratio, the specific fuel consumption of the engine and the mission profile. The fuel fraction is simply the fraction of the aircraft’s weight covered by fuel. "

Tejas mk1 compares well with its global peers in this fuel fraction aspect, which determines the combat range and endurance of fighters.

"The Tejas regularly flies non-stop between Bengaluru and Jodhpur & Bengaluru and Jaisalmer for various trials and exercises.

For example, flying between Bengaluru and Jaisalmer with two 1200 litre (l) drop tanks, the aircraft lands with 800 kg of fuel still onboard even after flying for 2.5 hours!

In fact, these flights are regularly done at 28,000 feet (because of air traffic regulations) instead of 35,000 feet where the endurance will be even greater.

Taking all these aspects into account it is easy to see why the endurance of the Tejas Mk1 and Mk1A is above 3 hours, pretty much like that of the Gripen C/D and the F-16, with whom it is being compared. With CFTs, the F-16IN can fly longer for about 4 hours. "


above photo gives tejas payload with 3.5 tons,


tejas payload with 4.05 tons,

"Now, how is this payload capability calculated? The designers simply take the maximum take off weight (MTOW) of the Tejas Mk1 which is about 14.1 t and subtract its clean takeoff weight (i.e. full internal fuel and no payload) of 9.8 t from the former. This gives a payload capacity of approximately 4.3 ton. "


above snap of tejas in Leh hot and high trials,


"On the other hand, one of the quintessential operational requirements for Indian borders is the ability to operate from high altitude airfields during hot summers.

‘Hot and high’ conditions severely impede any aircraft’s lift generation capability and thereby payload capacity. This is especially true of fighter aircraft with small wings. Image (https://i2.wp.com/delhidefencereview.com/wp-content/uploads/2020/05/image-3.png?w=696)
shows,

the Tejas being prepared for flight during hot weather trials at Leh Airfield, which is at an altitude of 10,682 feet above mean sea level,

with a payload of about 3.2 t. Once again, bear in mind that this is a test aircraft with 300 kg of extra instrumentation onboard.

Forget the two fighter aircraft it is being compared to, taking off with 3.5 t of payload during summer at Leh is near the what twin-engined medium-weight fighter can accomplish, while operating in similar conditions.

This is not surprising because the wing area of the Tejas is comparable to that of medium weight fighters."

read this article fully to know the facts about tejas ,
 

ersakthivel

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With HMDS coupled visually cued R73E missile, tejas mk1 is as good as any other fighter in close combat,

tejas mk1 has the combo of lowest wing loading coupled with higher Thrust to weight Ratio {TWR} in IAF, which allows for one of the Instantaneous Turn rates, {ITR},

this coupled with HMDS coupled visually cued R73 E missile makes it best in the close combat business,

because this ITR gives sharp nose pointing agility fr Tejas in close combat,
 

ersakthivel

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Tejas radome diameter is slightly higher than Rafale's

SO it gives you the ability to mount a decent sized AESA radar , with high TR module number,

Tejas mk1 has a ballast weight of 200 kg approx in its nose cone,

it can be replacd with AESA radar cooling unit,

Also tejas is relaxed static stability fighter with 4 channel digital fly by wire tech, (the top notch nervous system fr any modern fighter jet like F22, rafale, typhoon etc)

This will help tejas to be agile in close combat with the aid of low wing loading and high thrust to weight ratio.

So in a nutshell with just 4 air to air missiles,

tejas has the lowest frontal RCS and one of the most powerful AESA radars in IAF(barring future Su30 MKI upgrade's and probably rafale's)


with Astra missile and upcoming Astra mk2, tejas mk1A will be second to none in BVR or WVR in south asian skies,

Nowadays medium wave litening IRST unit tech itself is improving in leaps and bounds , and may get near nose mounted long wave IRST bubble,

So tejas mk1A itself is no slouch in any modern combat capability

All 40 tejas mk1s are upgradable to mk1A standards in MLU,
 

ersakthivel

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Tejas mk1 has a ballast weight of 200 kg approx in its nose cone,

it can be replacd with AESA radar cooling unit,


this is how 2052 AESA radar 's cooling unit is fixed into tejas,

for EW Tejas carries the same podded ELTA unit carried by SU30 MKI
 

Steven Rogers

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Mk1 and Mk1A will be point defence fighters. They will not be mandated to cross borders. Once MWF comes into the scene they will be posted in bases deeper in the hinterland rather than those closer to the border. But yes they will provide good BVR capability as well as CAS capability once enemy airspace is cleared. One thing to note is if SFDR is mounted on the Mk1As then with AWACS support A pack of 4 Mk1As will be able to shoot 16 SFDRs towards an incoming OPFOR package. And that is a very good thing indeed.
Totally BS,they will be very effective against the northern western enemy bases in the strike role,they too will be armed with SAAW and HSLD bombs,and hopefully RUDRAM series missiles,drdo has already showed intentions to add Brahmos NG with the Tejas....
 

ersakthivel

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So please stop misdirecting public with statements like,

"Maybe because it was an attempt, a long time after Marut, on designing a fighter. They would have wanted to get the max out of a simple design (you see the canards in MK2 now),

without too many control surfaces. This would make the control laws 'relatively' simple to write, test, refine and at the same time make the design less likely to fail.

All this might have resulted in a compromise on aerodynamics (F 35 ain't too nimble either, dosen't mean it's bad). "

A word about control laws tejas CLAWS ,

SAAB tried to develop this tech for grippenC and failed, SAAB's failure led to crash of wo grippen protoypes , leading to test pilots hurrying into retirement,

Then SAAB outsourced this critical tech to a US firm in Gripen C,

Even in nGripen NG , the same US firm is developing this CLAWS , fly by wire tech.

But ADA 's reliable and efficient RSS fly by wire CLAWS has drawn accolades from pilots around the world,

And now ISRO's shuttle prototypes, and future shuttles are relying on the same tech to land from space,

The reason ADA and NAVY, IAF are confident about short timelines fr Tejas mk2, TEDBF, AMCA is this indigenous CLAWS expertise by developed by ADA fr Tejas mk1.

Also both tejas mk2, and AMCA will have the same wing loading like tejas mk1,

In aerodynamics, wing loading is the total mass of an aircraft divided by the area of its wing.

This low wing loading enables fighters to take off and land with high loads from high altitude himalay airfield like LEH.

It also gives the fighter a sharp nose pointing ability via ITR,

SO Tejas mk2, AMCA fly by wire software will rely on the tried , tested and proved to be excellent CLAWSD effort of Tejas mk1,

canards are just additional surfaces for vortex aiding and short take off landing devices, that will require some modification of CLAWS

"
 

Dessert Storm

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Tejas radome diameter is slightly higher than Rafale's

SO it gives you the ability to mount a decent sized AESA radar , with high TR module number,

Tejas mk1 has a ballast weight of 200 kg approx in its nose cone,

it can be replacd with AESA radar cooling unit,

Also tejas is relaxed static stability fighter with 4 channel digital fly by wire tech, (the top notch nervous system fr any modern fighter jet like F22, rafale, typhoon etc)

This will help tejas to be agile in close combat with the aid of low wing loading and high thrust to weight ratio.

So in a nutshell with just 4 air to air missiles,

tejas has the lowest frontal RCS and one of the most powerful AESA radars in IAF(barring future Su30 MKI upgrade's and probably rafale's)


with Astra missile and upcoming Astra mk2, tejas mk1A will be second to none in BVR or WVR in south asian skies,

Nowadays medium wave litening IRST unit tech itself is improving in leaps and bounds , and may get near nose mounted long wave IRST bubble,

So tejas mk1A itself is no slouch in any modern combat capability

All 40 tejas mk1s are upgradable to mk1A standards in MLU,
Only IOC Mk1s would need to wait till MLU to be upgraded to MK1A, not the FOC ones.
 

Trololo

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Totally BS,they will be very effective against the northern western enemy bases in the strike role,they too will be armed with SAAW and HSLD bombs,and hopefully RUDRAM series missiles,drdo has already showed intentions to add Brahmos NG with the Tejas....
Not a problem as long as they are within Indian airspace. Hence the fitment of all standoff munitions.
 

ersakthivel

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The only shortfall of tejas mk1 is G limit of 8 point something Gs, and not reaching 9Gs at corner speeds,

tejas carries a big radar fr is weight class{ tejas mk1 has higher radome dia than gripen C and Rafale }
and it was expected to fit in the HAS of mig21 and basic mig 21 infra in alll forward bases,

So its length was also more or less he same as that of Mig21.

these factors limit the compliance of coke bottle shape

in whitcomb's area cross sectional ruling graph of

fuselage length Vs total fighter cross section .

just between its cockpit and radome base cone the cross sectional area increase is not as gradual as it is supposed to be,

Due to low wing loading requirement(with lengh being equal to mig21 constraint} gives it some what lessed finess ratio as well,

this gives rise to excess a bit excess "trans sonic drag" which limits its ability to hit 9Gs ,( above 8Gs, ) its increase in empty weight precludes its from tackling this drag with excess thrust.

All these are consraints are removed in mk2, (which is not bench marked on Mig21 length.)

but plus side of this is,

tejas mk1 has a far bigger radome dia than Gripen C and rafale , and with the advent of AESA radars, and long range BVR missiles , Tejas more than makes up this .5 G shortflall in another critical modern air combat niche of BVR .

Also due to its high G onset rate, (typical of low wing loading high thrus to weight ratio fighters with RSS fly by wire tech) it atains high Instantaeous Turn rate (ITR),

and

high offbore R73E WVR missile being slaved to HMDS,

Tejas mk1 always looks first, locks first, and shoots first in any modern WVR COMBAT

Tejas also has a high roll rate , which allows it to change its flight direction within seconds to escape being at the gun cross hairs of enemy
 

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