Wednesday, 28 October 2015

IAF wants aerial refuelling, jammers, quick turnaround in new Tejas

The SoP-18 Tejas fighter will have a turn-around time between missions of 14 minutes

By Ajai Shukla
HAL, Bengaluru
Business Standard, 28th Oct 15

In New Delhi on September 23, decades of friction came to an end when key stakeholders in the Tejas Light Combat Aircraft (LCA) finally agreed on the specifications of a fighter that would join the Indian Air Force (IAF) in large numbers, starting in 2018-19.

Termed “Standard of Preparation - 2018” (SoP-18), these specifications were agreed between four agencies. Besides the IAF, they include the Aeronautical Development Agency (ADA), which oversees the Tejas programme; Hindustan Aeronautics Ltd (HAL), which builds the fighter, and the ministry of defence (MoD).

SoP-18 involves four major, and several minor, improvements. As Business Standard reported yesterday (“Cutting edge Israeli radar wins air force approval for Tejas fighter”), a crucial enhancement in the SoP-18 Tejas will be “active electronically scanned array” (AESA) radar, which Israeli company, Elta, will develop with HAL.

Besides AESA radar, the SoP-18 Tejas will be equipped with the capability for air-to-air refuelling; a “self-protection jammer” (SPJ) mounted in an external pod to confuse enemy radar, and an improved layout of internal systems to ease maintenance.

HAL is currently building 20 Tejas fighters to the initial operational certification (IOC) standard. HAL chief, T Suvarna Raju says, over the next three years, production will ramp up from four aircraft this year; to seven in 2016-17; and eight in 2017-18, thus completing the order for 20 IOC fighters. From 2018-19 onwards, 16 SoP-18 Tejas fighters will roll off the line each year.

“Ramping up production to 16 Tejas per year will cost us about Rs 1,252 crore. We have mutually agreed that HAL will provide half the cost, and the IAF and navy will together pay the other half,” says Raju.

Meanwhile, ADA will continue developing the Tejas Mark II, replacing the current General Electric F-404IN engine with a new GE F-414 engine. The IAF remains sceptical about the Tejas Mark II, but the navy is certain the Tejas must have the more powerful F-414 engine to enable it to get airborne from short aircraft carrier decks.

That means that, along with the SoP-18 Tejas that would remain in production till 2024-25, the Naval Tejas Mark II would have to be somehow produced alongside.

Air-to-Air refuelling

The integration of air-to-air refuelling has been regarded as essential to give the Tejas enough reach. Currently, its internal tanks carry just 2,300 litres of fuel, with another 2,400 litres carried in external pods. However, external pods cannot be carried into battle, and they take up two weapon stations, reducing the fighter’s punch. Without external fuel tanks, the Tejas has a combat radius of barely 300 kilometres.

Air-to-air refuelling will step up combat radius to 500 kilometres. Towards that, a late prototype of the Tejas, numbered LSP-8, was fitted with an external fuel probe. This is being integrated and will soon undergo flight-testing.

Says a veteran fighter pilot: “As important than the ability to fight is the ability to turn up at the fight. That requires long legs and, for a light fighter, that requires air-to-air refuelling”.

External jammer pod

Tejas designers admit the absence of a jammer to throw enemy radar off the scent is a key vulnerability of the Tejas. While designing the fighter, they simply ran out of space for an internal jammer. With the IAF dropping its insistence on an internal jammer, ADA and HAL have now offered an “external jammer pod”.

While this threatened to reduce the Tejas’ weapons carriage by occupying one of its seven hard points, HAL is overcoming that problem by fitting a “twin-arm” at that hard point. “One of the arms will carry the jammer, while the other will mount an air-to-air missile”, says the designer.


For the IAF, which must mount multiple missions everyday with each Tejas fighter, easy “maintainability” and “low turn-around-time” are key attributes. The HAL chief says the IAF wants the fighter to take maximum 14 minutes between landing after a mission; and taking off for the next mission, fully checked, rearmed and refuelled. Currently, the Tejas takes about 20 minutes.

“The IAF has carried out a ‘maintainability evaluation’ on the Tejas, and provided requests for action (RFAs) to HAL. Each RFA deals with a particular way to improve maintenance. We will be making 27 modifications in the fighter”, says Raju.

The Tejas already has built-in-test-equipment (BITE), which is a software programme that automatically checks the functionality of every crucial system. In case an aircraft system is not working optimally, the BITE flashes a warning light.

On the other hand, if no warning lights are evident, maintenance engineers know that all systems are working satisfactorily. The need to check each one manually is no longer there.

This also involves fitting “pressure refuelling” of the kind that exists in Formula One racing cars, which requires fuel to be pumped under pressure into the fuel tanks. Refuelling the Tejas takes just four minutes, and two more to fill drop tanks as well. 


Anonymous said...

Pathetic production rate. HAL is completely displaying its diffidence. Compare this attitude to Sukhoi who have regularly produced aircraft first and then created a market for it because they met the user expectations. Does HAL have an ambition to export at all??

Anonymous said...

Is the AESA radar also developed under contract R&D where Israel keeps the technology and sales rights like Barak-8, LRSAM, MRSAM, etc?

Anonymous said...

When India scuttled the indigenous HF-24 program, it effectively killed generations of aerospace and defense industry build up...

After thousands of pilots falling from the skies, we did not learn any thing...
We still import everything including micro-light aircrafts...

I see a quantum change after Modi government but still I think India needs to know how to negotiate for contracts - technology and price...

May GOD bless India...

Anonymous said...

"its internal tanks carry just 2,300 litres of fuel, with another 2,400 litres carried in external pods. "

LCA carries 2458 kgs of fuel.

Kgs to Liters in fuel is roughly between 0.75 to 0.84Kg/L dependent on the temperature. So 2458kgs of fuel is roughly 3072 Liters using average of 0.8kg/L

Anonymous said...

Even the su-30MKI does not have an internal jammer. External is good, less interference, and easy to integrate and upgrade.

Anonymous said...

I wonder how Gripen NG manages 800 km combat radius.

Anonymous said...

How about Tejas having over head pylons like Jaguar or pylons at far end of the wings like F16.

Anonymous said...

It is a vicious circle,with users continuing to demand more and more new requirements to be built in and the builder taking more and more time to satisfy them !

gurinder said...

18 a year is too low. HAL needs to build up some production momentum, which in turn will convert into more orders. At least this project is not going the Arjun way .

Tako Nada said...

Any update about Rafael jet and how it can be superior against Chinese and Pakistani planes?

Jean Luc Picard said...

@ Broadsword : Is it Elbit or Elta that is Jointly developing the ASEA Radar with HAL ?

Paragraph 3, last line indicates Elbit.

Guru said...

Dear Ajai,

Slight correction on the combat radius range of 300kms mentioned in your blog. Per Govt of India press release, combat radius of HAL Tejas is 500 kms. Link below

Anonymous said...

Dear Ajai,

Slight correction on the combat radius range of 300kms mentioned in your blog. Per Govt of India press release, combat radius of HAL Tejas is 500 kms. Link below

This is also logical basis fuel burn rate of F 404 engine and fuel load (internal) of Tejas

Anonymous said...

hahaha ..SoP 2018-19 ...more specs - HAL will codevelop AESA lol...screwdriver HAL cant develop a a mechanical radar they will outdo themselves with the AESA...this sounds like IAF (Imported Air Force) playing the waiting game , wait for this NDA government with Modi's "Make in India" plan fail at the next elections in 2019 , hopefully UPA Madam and Saint will be back in power and imported air force can relaunch MMRCA ver2. A lot of imported air mashals in Chandigarh will earn their pensions.

NitishS said...

Fine article Col Shukla!

Its great that Tejas gets all these upgrades but even with IOC level Tejas, I have faith in the IAF that it will develop its tactics to incorporate best of the aircraft, It would have done so if we could afford only Bisons at this point of time..

As many say, numbers have its own quality, no bloody airforce would want to engage a swarm of tejas and that too an aircraft with such low RCS. A Tejas flying close to the ground might well be undetected for a long time till it has the target in range of its missiles.

Those tactics for Tejas will be developed in IAF squadron service, when Tejas is pitted against Su30s, Mig 29s, Mirage and also Rafale. If I could develop my tactic with all these different kind of aircrafts, I will go with it in war without thinking twice, making Tejas as effective as any other platform in the world.

All this being said, I think if at all we ever have a war, its just not going to be decided by Tejs or JF-17 or J20.. this nuclear heavy region of Asia has lots to lose if war mongers reign it. Im just hoping with Tejas, Indian manufacturing industry gets a boost and export orders so that our economy can grow and one day our country will not have any family without at least three meals a day.

Jai Hind!

Anonymous said...

TEJAS Mk1A - Made in India

Here are some details:

Engine - USA GE F414

Radar - Israeli ELTA 2052

Flight Controls - UK BAe Systems

Laser Pod : Israeli LITENING

ECM/ECCM - DRDO produced, but reverse engineered from Israeli designs.

AAR - Israeli refuelling probe system.

Ejection seat - Martin Baker or Russian

Weapons - French, Euro, UK, USA, Russian, etc.
(Astra, Derby, Python-5, R-77, R-73, Kh-59ME, Kh-59MK, Kh-35 & Kh-31, KAB-1500L, GBU-16, Paveway II, FAB-250, ODAB-500PM, ZAB-250/350, BetAB-500Shp, FAB-500T, OFAB-250-270, OFAB-100-120, RBK-500, Bofors 135 mm RP).

Inertial/Nav system/HUD - Mix of French, Israeli & Indian - locally integrated.

Airframe - HAL -

The last attribute makes it "HAL TEJAS" - a true tri-colour product of Indian ingenuity.

Rami said...

The radar system was developed by Elta, not Elbit. Elta does radar systems, Elbit supplies helmet mounted sights, ECM systems and the like.

I'm glad to see the Tejas finally coming into shape. The addition of the radar upgrade was key. The EL/M-2052 was developed as a modular plug-in replacement for the EL/M-2032, which was already integrated into the Tejas Mk 1. Unlike the U.S., the Israelis had a modular upgrade plan for their mechanically scanned radars - an outgrowth from the Lavi fighter program cancelled in 1987.

I noticed that there's a new book coming out on the Lavi at year-end.
Despite canceling the production program, the Israelis are still reaping the benefits of that R&D effort, decades later. Something India can learn from.

Rajanikanth S. Shastri said...
This comment has been removed by the author.
anonymous said...

Great article Col Shukla!
Can you please check the turn around time details, I'm pretty sure 14 mins is not practical... And unless the pilot remains strapped in during hot refuelling, there is no way any military aircraft can be turned around in such a short time. (Missiles can't be put in any case) Does it have hot refuelling?

Anonymous said...


Lets add more to your list:

Flight Controls - UK BAe Systems - actually being replaced by ISRO developed systems by next year
FBW - the most important part of the jet - Indian, ADA and NAL
Overall design - ADA, Indian
Aerostructures including composites (45% by weight) and most of the surface area - HAL, NAL, Tata, India
Avionics - HUD, Mission computing, displays, munitions control - ADA, pvt firms, BEL, HAL, Indian
Hydraulics & systems - HAL, Indian

Overall % by LRU which is Indian: 60%
HAL and ADA are now looking to raise it further since SP orders give more leeway to private firms for long term planning

In short, nice try with the snide remarks - but hardly factual

Valleesha Kumar said...

Which are the non agreed RFA s of LCA From IAF by ADA?