LCA TEJAS MK1 & MK1A: News and Discussion

[SARTHAK]

1500 +for du 30 mki can be done , only thing that hinder is power

GaN uses lesser power than GaA

 

[Roland55]

You know, this might have little to do with the discussion we have, but what eve happened to the technology demonstrators ? Stored, scrapped, idk used as training equipment?

 

[omaebakabaka]

What fighter jet requires less maintenance?

Answer (1 of 5): The HAL Tejas requires the lowest maintenance among any 4/4.5th generation fighter in operation today. The Tejas uses majorly carbon composites over metal in its making. It has the highest usage of composites of any fighter jet in the world. The composite materials constitute 45...

www.quora.com

Bhai, a bit premature to claim it....engine apart?

 

[abingdonboy]

Is that NP-5?

 

[abingdonboy]

Better angle, must be NP-5

edit, notice the LEVCONs, it’s a NP

 

[Roland55]

Is that NP-5?

View attachment 142846

That looks like a 5 to me...i guess?

 

[Dark Sorrow]

GaN uses lesser power than GaA

GaN devices can operate at higher temperatures and higher voltages than either GaAs or silicon so they can deliver higher power. GaN can operate at five times higher voltage and twice the current of GaAs devices, have higher potential power-added efficiency than GaAs above 10 GHz and silicon above 1 GHz.

From where you can to conclusion that GaN uses lesser power than GaAs?

 

[Dark Sorrow]

1500 +for du 30 mki can be done , only thing that hinder is power

AL-31 are powerful enough to provide necessary power to 1500+ Uttam AESA. Primary concern is power dissipation and how will this heat be extracted from the radar. As of today we do lack is thermal dissipation domain. Even for our DRDO/DARE SPJ we imported thermal dissipation solution from Israel.

 

[Blademaster]

Hey guys aerodynamics and air intake designs are very important. Gripen super cruises inspite of being havier than Tejas.

Yes that's true... That's where experience in designing craft come into play. If you look in

The mk2 will definitely improves on that but then there is always a limit.

The GE F414 won't provide the thrust required to do so .

All that came from the stupid fetish of being the smallest fighter mindset. They were coming from the Gnat/Ajeet mindset. Too bad we couldn't make a clean sheet redesign in the 2000s.

 

[abingdonboy]

All that came from the stupid fetish of being the smallest fighter mindset. They were coming from the Gnat/Ajeet mindset. Too bad we couldn't make a clean sheet redesign in the 2000s.

Contrary to some common belief it’s actually more challenging to make something capable and light as you run into issues with packaging and miniaturisation quite quickly, listen to the blue sky podcast with J. malonker, he touches on this topic and says this restraint spelt out in the original IAF ASQRs created huge technical challenges. All because they wanted to be cheap and short termist to get the LCA to fit the MIG-21’s HAS


They should’ve gone for something of the Mirage 2000 size from the outset or even a 2 engine version (mirage 4000esque) and then you can scale down/miniaturise as you refine your design and if you need it. Instead they went completely a$$ backwards

 

[Flying Dagger]

A two engine version would have been ideal way to go like Rafale.

But i believe inexperience in designing or producing them and cost to operate etc all played in the mind of IAF HAL and ADA.

With Jaguar though we saw how a two engine fighter could be low maintenance and cheap to operate too.

We should have worked up from HAL Marut HF 24.

What's lost is lost though hopefully mk2 and Amca turn out on time.

 

[abingdonboy]

A two engine version would have been ideal way to go like Rafale.

But i believe inexperience in designing or producing them and cost to operate etc all played in the mind of IAF HAL and ADA.

With Jaguar though we saw how a two engine fighter could be low maintenance and cheap to operate too.

We should have worked up from HAL Marut HF 24.

What's lost is lost though hopefully mk2 and Amca turn out on time.

IAF started out asking for a simple MIG-21 interceptor replacement. Over the years they kept adding requirements

No way is LCA MK.1 what ADA would design with a clean sheet if current ASQRs were given to them in 1990

 

[Flying Dagger]

IAF started out asking for a simple MIG-21 interceptor replacement. Over the years they kept adding requirements

No way is LCA MK.1 what ADA would design with a clean sheet if current ASQRs were given to them in 1990

Because there was delay from the time when requirement was raised

From 70s early 80s to 2000s things will obviously change.

The real problem was we didn't had expertise experience etc to do that in timely manner initially funding was an issue too due to our economic conditions linking kaveri with Tejas delayed it. And then restrictions after pokhran etc . Many factors were behind it.

 

[Spitfire9]

A two engine version would have been ideal way to go like Rafale.

But i believe inexperience in designing or producing them and cost to operate etc all played in the mind of IAF HAL and ADA.

With Jaguar though we saw how a two engine fighter could be low maintenance and cheap to operate too.

We should have worked up from HAL Marut HF 24.

What's lost is lost though hopefully mk2 and Amca turn out on time.

How many more Marut would have been built if India had taken up the RR offer to make a higher thrust engine for - in today's terms - a pittance? A longer production run might have kept a team of engineers together longer and a bank of engineering expertise alive to give Tejas a better start.

 

[Roland55]

I know its too early to call it something...but, the chief of the Argentine Air Force is currently in India along with a delegation. I would guess that with the whole russian invasion scrapped any posibility of buying the Mig-35, the Tejas offer is probably being taken a bit more seriously? (still not sure, i wouldnt count on it)

Spoiler: Tweets

Like i said, i wouldnt count on it, for now its all speculation.

 

[shuvo@y2k10]

GaN devices can operate at higher temperatures and higher voltages than either GaAs or silicon so they can deliver higher power. GaN can operate at five times higher voltage and twice the current of GaAs devices, have higher potential power-added efficiency than GaAs above 10 GHz and silicon above 1 GHz.

From where you can to conclusion that GaN uses lesser power than GaAs?

GaN radars have lesser power consumption compared to GaAs radars, and ability to operate at higher volatage levels. This translates to more radiative power output; if both radars are fed the same electrical power input.

 

[Dark Sorrow]

GaN radars have lesser power consumption compared to GaAs radars, and ability to operate at higher volatage levels. This translates to more radiative power output; if both radars are fed the same electrical power input.

Lets analyze the statement.

Their is no such thing as GaN radars. GaN is used to build AFE of the TR Modules. That roughly comprises of 33% of TR Modules. Rest of TR module is all the intelligence that is required for the TR Module, SDR, interfacing with Radar Computer, cooling, etc.
Radiated power output depends on lot of things like antenna design, beam-forming capabilities, accuracy of beam steering, side lobe, SNR, heat extraction capabilities arising from power dissipated, T/R module's manufacturing tolerances,

GaN’s high power density, or its ability to dissipate heat from a small package, makes it so impressive. While GaAs has a basic power density of about 1.5 W/mm, GaN has a power density ranging from 5 to 12 W/mm. Unlike GaAs, the high breakdown voltage of GaN supports high electric field strength in the device. By operating at a higher voltage, GaN-based amplifiers are able to provide a much higher output power in a smaller space.

Using GaN technology in the design of the TR module’s power amplifier maximizes the transmit output power while minimizing the physical size. In addition to shrinking the size of the amplifier die, the use of high-power GaN reduces the need to use many lower-power devices. Since the passive combining networks that are used to combine multiple die are large and introduce loss into the signal path, having fewer of them improves the power density in the TR module.

GaN offer high power density, but when compared to GaAs, the higher bias voltage of GaN simplifies the process of designing a broadband impedance match. This enables a single GaN amplifier to operate over a wide bandwidth, enabling robust and multifunction AESA systems.

The higher bias voltage of GaN offers an additional benefit at the circuit level. Since power is the product of voltage and current, for a constant power, the higher bias voltage of GaN leads to lower current. When the current is reduced, the loss in the bias circuit is also reduced, which improves the efficiency of the amplifier.

GaN technology – while it can improve the performance of the output amplifier in the TR module – can also be used on the receive side. It’s a fact that maximizing the SNR requires both increasing the signal strength and decreasing the noise; when the receiver chain is examined, one source of noise is the protection limiter at the input to the low-noise amplifier since each dB of loss in the limiter equates to an additional dB of noise figure. By using GaN as the semiconductor material for the LNA, it is possible to design out the limiter since GaN can withstand higher input voltages without damage. This leads to a net improvement in the receiver’s noise figure, maximizing the SNR and the range of the radar system. Also, by removing the limiter from the design there is more space in the TR module for other circuitry.


GaN is nowhere compared to GaAs for having lesser power consumption.

 

[Flying Dagger]

GaN radars have lesser power consumption compared to GaAs radars, and ability to operate at higher volatage levels. This translates to more radiative power output; if both radars are fed the same electrical power input.

Higher voltage also means current drawn will be more in same amount of time.

Gallium nitride is a semiconductor which can be used in ew systems

Don't read too much other than that power consumption won't reduce.

Now the real advantage is the reduction in size of ew systems radar etc by use of GaN . That also means their will be less loss of power in transmission. Efficiency will be more. .. but doesn't mean any drastic decrease in power consumption.

Another advantage apart from its size is range.

That's it.

 

[johnj]

Well Mig 31 is essentially an improvement overthe Mig 25 so as you have requoted satellite made the reconnaissance part useless.

Other advantage was speed where Mig 31 only excels to intercept big radar etc.

Well Sukhoi provided more... Big radar can intercept with long range missiles and unlike mig 25/31 can dog fight and provide air superiority.

So Sukhoi essentially ended the need of Mig25/31 other advantage too.

Regarding maintenance if we really needed it we would have maintained it somehow or bought mig 31. But with Sukhoi and satellites etc there wasn't much need.

For Russia having such a very large territory it might be meaningful to still have them.

Super Flanker only saying what IAF once said during that time. Its not about interceptor but spy plane.

 

[Flying Dagger]

Super Flanker only saying what IAF once said during that time. Its not about interceptor but spy plane.

Can you please elaborate your point.


Yes Mig 25 were our spy plane for reconnaissance mission since no other fighter jet could fly that high and engage then. They were fast interceptors for Soviet who needed it but not much for dogfight.