Indian Military Aviation

Singha · Post by **Singha** » 30 Nov 2011 11:33

ramana being mech you had the run of the place. until 1990 batch, there was a workshop machines lab for all branches in 2nd yr 1st sem where they learnt how to use lathes and milling machines. 1st yr was the basic workshop lab. then from 1991 (my batch) in a fit of 'alignment to industry focus' this 2nd yr lab was removed for all but mech and meta students. never mind all much machines now need EE and CSE input...in a better system people who wanted would be encouraged to take x-disciplinary courses but not in the 'industry alignment' craze where only c++ and java was respected. there was a electrical machine motors lab for all branches too in 2nd yr..not sure if another round of getting ready for infy pipeline took care of removing that after us.

not sure whats the scene now. but the days of carefree exploration are probably long gone. people are probably preparing for google and facebook entrance exams in 1st yr, and keeping track2 diplomacy open to MS professors. everything has become destination and results focussed, no pleasure in the journey...

VinayG · Post by **VinayG** » 30 Nov 2011 11:45

ramana wrote:In my days the principal of REC Warangal was Gp Capt(retd) MJ Kriplani who was an engineer officer from IAF. He persuaded the IAF to give a Mig 21 engine from a crashed plane. This was in display in the workshop or the engine lab for a long long time. BTW the workshop Supdt was also a retired Army Officer who kept the workshop floor spotless clean even with unruly and klutzy students. One great annual event was the firing up of the cast iron melting cupola for the fourth year mech students sand molding class.

aharam that will give you when I was at RECW!

Tell us about your flying experiences.

Thanks, ramana

ramana sir sorry for off topic maadhi hanamkonda meeru telugu matladuthara i am from hanamkonda warangal now living in US i saw that engine during REC fest during my school days. i think you might have know Apparao sir HOD of chemistry department

Surya · Post by **Surya** » 30 Nov 2011 12:12

aharam welcome to BRF

who cares about engg workshops and HODs

We want to know your flying experiences!!!!

Especially in this thread

Bala Vignesh · Post by **Bala Vignesh** » 30 Nov 2011 12:33

Aharam Sir,
Welcome to BRF. Could you please post some tidbits from your experiences in the IAF, especially flying the 21's..
Thanks.

Shubham · Post by **Shubham** » 30 Nov 2011 12:47

Singha wrote: if anything we need even more hawks. for the IAF to expand, the pipeline of young pilots must be fat ..we need to pump out more graduates in each batch to cope with the expanding IAF...100s of helicopters, 10s of transport a/c, 100s of fighters are coming within the next decade and older pilots retiring.

Unfortunately there is nothing IAF can do to churn out the number of pilots it wants without cutting corners. Just pray hard that Pilatus PC-7 is inducted as planned.

Is there any chance IJT could be inducted by 2013 ??

Kersi D · Post by **Kersi D** » 30 Nov 2011 19:08

ramana wrote:The engine AL-55 was a fiasco.

Me thinks the first IJT flew with Tubomeca Larzac. Then Natasha offered AL 55 and India fell hook line and sinker

Aa bail muhje maar.

K

Kersi D · Post by **Kersi D** » 30 Nov 2011 19:18

shiv wrote: I just wonder (and this is normal for India) if there is some babu oor minister or file pusher at DGCA who an be bribed by a foreign seller of trainer aircraft to ensure that the IJT file does not move at all. It would be ironic if we sit here and curse HAL while it is the DGCA screwing things up...

I would not put it beyond us Indians. A few decades ago I was working for a reputed engineering company in the field of offshore platforms for ONGC. ONGC issued a global tender for a largish (water injection) platform. We sought collaboration with a number of western companies. They all reused. They said that as per their source this tender is rigged in the favour of a far eastern company. ONGC asked Mazgaon Dock Ltd to quote. MDL sends a letter saying that this equipment is beyond their capacities not withstanding that MDL had already supplied a bigger and more complex equipment !!!

Indian Shining

K

Kersi D · Post by **Kersi D** » 30 Nov 2011 19:19

ramana wrote:What is the heaviest dumb bomb that can be carried by the ground attack planes?

And what does IAF have?

Probaly 1000 lbs, 452 kg

K

saps · Post by **saps** » 30 Nov 2011 19:31

Can someone dig up on "Weather the larzac powered IJT was meeting the ASR specs", my take is that it wasnt by even a long shot.

Any guru's who would like to throw any ideas...

ramana · Post by **ramana** » 30 Nov 2011 21:04

Can they use those 100+ Adour engines from the Jag upgrade for the IJT?

Bala Vignesh · Post by **Bala Vignesh** » 30 Nov 2011 21:24

Wouldn't the adour be too heavy for the airframe of IJT to handle??

srai · Post by **srai** » 01 Dec 2011 12:14

saps wrote:Can someone dig up on "Weather the larzac powered IJT was meeting the ASR specs", my take is that it wasnt by even a long shot.

...

Yes, the IJT was underpowered with the Larzac engines as per reports. But HAL chose the Larzac engines knowing the ASR specs. IMO, HAL should have taken the approach of LCA Mk.1 and Mk.2 variants have taken. Go with slightly under specs Mk.1 configuration (with proven engines) to validate the full flight test program and put it into limited number of units production and service. Then when Mk.2 ready with a more powerful engine, do additional flight testing (but not the whole flight test program) to validate the new engines on the aircraft.

Singha · Post by **Singha** » 01 Dec 2011 12:26

article from 2010:

IJT completes Hot Weather Trials with new AL-55I engines

IJT-36 also known as ” Sitara ” has successfully completed Hot Weather Trials with new Russian made AL-55I engines in Jaisalmer. Both PT-1 and PT-2 prototype aircraft which where involved in the tests are both back in Bangalore now .

This is second time IJT-36 has been successfully completed Hot Weather Trials , earlier test where done using Snecma Larzac 04-H-20 turbofan non-afterburning engine , which needed to be changed since Air force issued new Air Staff Requirements in mid way of the project. delays in fabricating and testing of the new engines have delayed the project by three years now .

IJT with Russian made AL-55I engines first flew only in Feb 2009 , first batch of 12 LSP IJT-36 have are already been produced and soon will be handed over to air force for testing , new LSP models are sporting new Anti-spin strips on its nose cone section .

IJT-36 are fully combat capable and can be used as light attack fighter or used in COIN operations , it has five external hard points and can carry up to 1000kg payload .
....

aharam · Post by **aharam** » 02 Dec 2011 06:29

ramana wrote:In my days the principal of REC Warangal was Gp Capt(retd) MJ Kriplani who was an engineer officer from IAF. He persuaded the IAF to give a Mig 21 engine from a crashed plane. This was in display in the workshop or the engine lab for a long long time. BTW the workshop Supdt was also a retired Army Officer who kept the workshop floor spotless clean even with unruly and klutzy students. One great annual event was the firing up of the cast iron melting cupola for the fourth year mech students sand molding class.

aharam that will give you when I was at RECW!

Tell us about your flying experiences.

Thanks, ramana

Well ramana, I was after your time, but certainly before the time quoted by singha. I still had 2 years of workshop, with milling machines and lathes in the second year, even though I was not in ME. To give you an aviation timeframe, which is probably more appropriate, M2K and Mig29 were brand new platforms, much envied by us Mig 21 pilots.

As for flying experiences, as you probably guessed, it was a long time ago. I moved to the US shortly after and haven't flown anything faster than a Cessna 172 in nearly two decades

That said, it was quite a bit of fun while it lasted. At the time, the primary focus was on WVR and merges, and that's what we were trained in. In that role, the Mig 21 was an excellent plane. Very light, beautiful turn characteristics - much like driving a sports car. It is not a forgiving plane and was designed in an era, where much more pilot attention had to be focussed on the basics. No FBW, so you had the whole flight envelope to yourself. This also meant that you had to be very careful with an aircraft that had its CG well aft of the pilot. You could into a deadly flat spin in certain stall conditions. In my years, I don't recall it being a "flying coffin" as it is termed now - you had to careful, it was drilled into us and training did involve recovery from various stall geometries. If you paid attention, it was not a dangerous plane per se. Then you get into a phase, where you are far more comfortable with the aircraft, so much so that regular sorties feel like a drive to the grocery store - albeit a fast drive

. That's the dangerous part, because the plane is unforgiving of mistakes and when you get too comfortable, you are apt to miss something. When I see the crash statistics now, I am not sure if it is the pilot or the plane. The airframes are quite old now and maintenance was always an issue. In my time, each plane in the squadron was unique in that something about the feel was different, either the flight envelope, handling or even something as small as a nose wheel shimmy on landing or takeoff forcing you to keep pressure off of it. As the plane ages, these can get exacerbated and can cause crashes. Another possibility is simply that training is focussing more on FBW, where the flight envelope is determined by the computer, which has it own limit settings to ensure that you don't deviate. Much safer, but once you get used to no envelope restrictions, I don't know how FBW would feel - I never flew an FBW fighter, so I can't compare.

The Mig 21 certainly belonged to another era of fighter design. Light and agile. I don't know if folks here have read John Boyd's work on maneuverability, the 21 was the epitome of it. The agility of a plane is not just its specs - turn radius, climb rate, thrust/weight ratio. In WVR, it has much more to do with how rapidly you can change the attitude of the plane, for instance changing the direction of a roll. A plane that can rapidly switch from one position/attitude to another without losing much energy holds an advantage in a merge, since it can engage and disengage at will. That was the real fun of a lightweight interceptor. With heavy class fighters, particularly with TVC, although they can turn and climb very rapidly, I am not sure how many attitude/position transitions they can go through without losing significant energy. Energy is still critical at the end of the day - it is what you can accomplish with a given amount of energy that determines the better plane. All of this of course assumes identical pilot skills, which is generally not the case. With most engagements now in the BVR regime, I am not sure if the WVR regime is that important, which is why the 21 is from a different era. Small highly agile light fighters are not there any more and probably not needed in a networked environment where the aircraft is a delivery platform. Even the vaunted F16 is a lot heavier than when it started, and I am not sure it will really keep its edge in the presence of a competently flown 21 in the WVR regime.

Enough with my rambling for now. Would love to hear feedback. The discussions that I have been lurking on have invariably been great.

Cheers
aharam

shiv · Post by **shiv** » 02 Dec 2011 06:41

Thanks for the inputs Aharam. I doubt if training nowadays emphasizes FBW because training itself has been on the MiG 21 for decades. That is even after you left. Pilots have been graduating from the Kiran to the MiG 21 for lack of an advanced jet trainer - which has now appeared recently in the form of the BAe Hawk. In any case the only FBW fighters that the Air Force had were about 40 Mirage 2000s and of late the Su 30.

Thank you once again for making the point that "flying coffin" is an unfair description. Other pilots who fly/flew the MiG 21 say what you say, but we the Armchair Marshals of BRF keep coming back to insist that we know better than you guys

and that we wish to swallow wholesale the media creation of that name.

And welcome to BRF..

aharam · Post by **aharam** » 02 Dec 2011 06:53

shiv wrote:Thanks for the inputs Aharam. I doubt if training nowadays emphasizes FBW because training itself has been on the MiG 21 for decades. That is even after you left. Pilots have been graduating from the Kiran to the MiG 21 for lack of an advanced jet trainer - which has now appeared recently in the form of the BAe Hawk. In any case the only FBW fighters that the Air Force had were about 40 Mirage 2000s and of late the Su 30.

Thank you once again for making the point that "flying coffin" is an unfair description. Other pilots who fly/flew the MiG 21 say what you say, but we the Armchair Marshals of BRF keep coming back to insist that we know better than you guys and that we wish to swallow wholesale the media creation of that name.

And welcome to BRF..

Thanks Shiv. I read several of your posts with interest. I didn't realize, we still had the same Kiran -> Mig 21 path today as I had decades ago. Wasn't the Hawk inducted years ago, if so what is the delay in using it? It is a big transition from sub-sonic to supersonic regime and more importantly the flight characteristics are quite different. Kiran is quite docile. The 21 in sub-sonic, particularly low subsonic flight does take a bit of handling - the thin delta wing doesn't have great lift, but it compensates for it with low drag in the transonic and supersonic regime. Landing the 21 with its high angle of attack attitude due to low wing lift is also another challenge.

Also, didn't realize that FBW is not very common yet. Thought with the proliferation of Su30, that should have gone up a bit. Have there been any upgrades on the Mig 29 platform for FBW?

Cheers
aharam

aharam · Post by **aharam** » 02 Dec 2011 07:01

pandyan wrote:aharam sir - any thoughts on the LCA? Welcome to club!

LCA certainly fits the bill in the light class fighter. However, not having flown it

, I can't really comment on its feel. In today's BVR era, the characteristics that made a great fighter in the 60s or 70s are probably not that relevant. What probably matters more is KE features, radar and missile engagement range and a first to see/first to shoot advantage. While WVR cannot be discounted entirely, design trade-offs will certainly be biased against it.

Just my 2 cents. I am not an aircraft designer, and I certainly don't think I am qualified to comment on an aircraft that I haven't even seen apart from the specs

Cheers
aharam

shiv · Post by **shiv** » 02 Dec 2011 07:16

Aharam the Hawk has been inducted only in the last 4-5 years in some numbers and Bidar is full of them. But as per a recent issue of Vayu - it is still the instructors who are getting fully familiar with the type, and I guess pilots who graduated on the Hawk are now still fairly junior. Ironically this same subject we recalled in perhaps the same issue of Vayu in a nostalgic article about the HF-24 and the subsequent 2 seater that could have been a trainer . The HF-24 being underpowered was rejected as being unsuitable for the relatively short runway at the above 2000 feet MSL runway at Hakimpet. But ironically the MiG 21 training was placed at sea level Tezpur. The HF 24 was never tried.

shiv · Post by **shiv** » 02 Dec 2011 07:18

aharam wrote: Just my 2 cents. I am not an aircraft designer, and I certainly don't think I am qualified to comment on an aircraft that I haven't even seen apart from the specs

What!! Just Google for it and you will be the expert. Now what was it you wanted to know about nuclear bomb designs?

aharam · Post by **aharam** » 02 Dec 2011 07:30

shiv wrote:Aharam the Hawk has been inducted only in the last 4-5 years in some numbers and Bidar is full of them. But as per a recent issue of Vayu - it is still the instructors who are getting fully familiar with the type, and I guess pilots who graduated on the Hawk are now still fairly junior. Ironically this same subject we recalled in perhaps the same issue of Vayu in a nostalgic article about the HF-24 and the subsequent 2 seater that could have been a trainer . The HF-24 being underpowered was rejected as being unsuitable for the relatively short runway at the above 2000 feet MSL runway at Hakimpet. But ironically the MiG 21 training was placed at sea level Tezpur. The HF 24 was never tried.

It is interesting that it is taking this long. For an intermediate transonic jet trainer, there are not a whole of requirements. You could even get something like the Aero L-29 or L-39 in numbers and be done with it. They are relatively inexpensive and in the US, they are used for training folks that like to fly/own old warbirds like a Mig-21. I have no idea, why the Hawk induction down the chain is such a time sink. It would be a sad answer if it really is the transition from Kiran to Mig 21 that is the cause of the accidents and we are still delaying jet trainers that most jet flying countries got right in the 50s.

I agree, they should have used the Marut as a platform to design a series. Its cancellation was a major backwards step for the Indian aviation industry. Incidentally, the Marut designer - Kurt Tank, was very well known for his Focke-Wulff 190 design. Insufficient power should never be the excuse - the first American jet engines in the 50s were way underpowered. Didn't stop people from building and buying generations of planes, till T/W ratio was adequate.

Cheers
aharam

aharam · Post by **aharam** » 02 Dec 2011 07:43

shiv wrote:The HF-24 being underpowered was rejected as being unsuitable for the relatively short runway at the above 2000 feet MSL runway at Hakimpet. But ironically the MiG 21 training was placed at sea level Tezpur. The HF 24 was never tried.

BTW, the thin delta of the 21 has very poor lift in low-subsonic, so you land with a fairly high nose-up attitude. As the runway elevation increases, the air gets thinner and this problem gets worse. It was already a big issue seeing the runway during landing. Landing at higher altitudes was certainly not for beginner pilots.

That said, I think a HF-24, even underpowered would have been far more docile landing at higher altitudes than a 21. Heck, if you really want a challenging landing, you should try a Cessna under high cross-winds. Almost no power at landing, big wings that really catch the breeze, and in a cross-wind the plane banks dangerously. When I flew one, I gained a healthy respect for pilots of little planes flying in adverse weather. At least I had power to get me out of a low speed mess in a jet

Cheers
aharam

shiv · Post by **shiv** » 02 Dec 2011 08:11

aharam wrote: I agree, they should have used the Marut as a platform to design a series. Its cancellation was a major backwards step for the Indian aviation industry. Incidentally, the Marut designer - Kurt Tank, was very well known for his Focke-Wulff 190 design. Insufficient power should never be the excuse - the first American jet engines in the 50s were way underpowered. Didn't stop people from building and buying generations of planes, till T/W ratio was adequate.

Aharam Air Marshal (retd) Rajkumar wrote an article about flight evaluation of the Alpha Jet and Hawk in France and the UK respectively The article is here
http://vayuaerospace.in/images1/Advanced_Jet.pdf

The last paragraph says:

Unfortunately the techno-economic
negotiations with Dassault and BAe
could not be completed by HAL and
a three month extension till 30 June
1987 was sought, to which the Ministry
agreed. Then, on 17 April 1987, Chitra
Subramaniam, the Hindu newspaper
correspondent in Geneva, broke the
‘Bofors story’. After that no bureaucrat
or politician in Delhi would touch a
defence deal with a barge pole - and
the rest is history. Dassault eventually
pulled out of the competition and the
Hawk AJT was finally inducted into the
IAF in 2006, or some 20 years after our
evaluation visit!

There may well be a link between the rejection of the Marut and he Bofors scam/Hawk delay. Contempt for Indian products that lead to easy rejection open the door for imports where vendors are ready with bribes, kickbacks and sweeteners

I reviewed the book by "Nosey" Haider the Pakistani pilot who led the Pathankot raid in 1965. The book is less about war stories and more a lament about Pakistan. But he does point out how even Zia ul Haq was into the business of taking kickbacks from military vendors. Military sales people abroad are accustomed to "turd world" people taking kickbacks and their sales systems operate around middlemen and this kickback system

Here is my book review:
http://www.bharat-rakshak.com/IAF/Books ... alcon.html

Haider tops off his book with an expose of the extreme corruption that has gripped Pakistan. The first hint of kickbacks to middlemen in Pakistan comes early on in the book when a wealthy Pakistani middleman was present for the trials of Hispano-Suiza rockets by the PAF in the late 1950s. But Haider singles out the Zia ul Haq regime and the period after that for its extreme corruption where kickbacks were “received on every commercial deal” (page 388). A US $ 890 million deal with France for Submarines was inflated to US$ 1.2 billion for the kickbacks. In a later deal shoulder fired Mistral SAMs were hurriedly acquired on the pretext that an Indian and Israeli attack was imminent on the Kahuta nuclear complex, despite the fact that such missiles would be useless in the event of such an attack.

ramana · Post by **ramana** » 02 Dec 2011 10:41

aharam, Welcome and good luck in your new career. Do contribute to the discussions time permitting.

Surya · Post by **Surya** » 02 Dec 2011 11:05

Other pilots who fly/flew the MiG 21 say what you say, but we the Armchair Marshals of BRF keep coming back to insist that we know better than you guys

Most on BRF do not agree with the media's calling of the Mig 21 a flying coffin.

Aditya_V · Post by **Aditya_V** » 02 Dec 2011 11:20

Kersi D wrote:
ramana wrote:What is the heaviest dumb bomb that can be carried by the ground attack planes?

And what does IAF have?
Probaly 1000 lbs, 452 kg

K

Aharam sir, can you tell us with your time in the airforce what the heavyest DUmb bombs that the IAF has- if the information is not classified. I remember from Kargil that the Mig-27's normally used 500kg bombs.

sum · Post by **sum** » 02 Dec 2011 14:29

Another MiG-21 goes down:

14:25 'Flying Coffin' MiG 21crashes in Haryana, no casualties : Just in: A MiG 21, also called a Flying Coffin, has crashed in Sirsa in Haryana. No casualties have been reported.

DDM chips in with "also called a flying coffin"..

venku_Raj · Post by **venku_Raj** » 02 Dec 2011 15:05

MiG-21 crashes in Haryana, pilot safe

aharam · Post by **aharam** » 02 Dec 2011 22:34

Aharam sir, can you tell us with your time in the airforce what the heavyest DUmb bombs that the IAF has- if the information is not classified. I remember from Kargil that the Mig-27's normally used 500kg bombs.[/quote]

The 21 was capable of carrying 250 Kg and 500 Kg dumb bombs. But it was not used in a ground attack role, mostly older A2A missiles, with the bomb pylon typically used for a drop tank to extend range. I am not sure what the heaviest bomb would be, but for a fighter class aircraft, from what I remember it was 500 Kgs even for the Mig 27. Payload on the 27 is higher though.

Cheers
aharam

Singha · Post by **Singha** » 02 Dec 2011 22:50

M2K's dropped 1000lb iron bombs in kargil.
the Matra BGL-1000 is also in our inventory.

its been mentioned that US default iron bombs (BLU-109/Mk84) are 2000lber. and same thing is used for JDAM. they like to hit hard and have the assets to do it (F15 and F18 mainly, though F16 also does it)
they also have 1000lb bombs...perhaps the f-16s use these more.

Lalmohan · Post by **Lalmohan** » 02 Dec 2011 22:59

nato standard was 1000lb'er
the US used to use 500lb and 1000lb dumb bombs
paveways are fitted to 500, 1000 and 2000 lb'ers
now going back to 250 and 125 lbs to minimise collateral damage

soviet standards were 250kg, 500kg and 1000kgs IIRC

Cain Marko · Post by **Cain Marko** » 03 Dec 2011 01:12

aharam wrote:The Mig 21 certainly belonged to another era of fighter design. Light and agile. I don't know if folks here have read John Boyd's work on maneuverability, the 21 was the epitome of it. The agility of a plane is not just its specs - turn radius, climb rate, thrust/weight ratio. In WVR, it has much more to do with how rapidly you can change the attitude of the plane, for instance changing the direction of a roll. A plane that can rapidly switch from one position/attitude to another without losing much energy holds an advantage in a merge, since it can engage and disengage at will. That was the real fun of a lightweight interceptor. With heavy class fighters, particularly with TVC, although they can turn and climb very rapidly, I am not sure how many attitude/position transitions they can go through without losing significant energy. Energy is still critical at the end of the day - it is what you can accomplish with a given amount of energy that determines the better plane. All of this of course assumes identical pilot skills, which is generally not the case. With most engagements now in the BVR regime, I am not sure if the WVR regime is that important, which is why the 21 is from a different era. Small highly agile light fighters are not there any more and probably not needed in a networked environment where the aircraft is a delivery platform. Even the vaunted F16 is a lot heavier than when it started, and I am not sure it will really keep its edge in the presence of a competently flown 21 in the WVR regime.

Enough with my rambling for now. Would love to hear feedback. The discussions that I have been lurking on have invariably been great.

Cheers
aharam

Well sir, what are your thoughts on the MiG-21 Bison? I believe it still retains its old advantages but now has an HMS and BVR capability. Your bird sir, is still in the fray in today's world. And if the USAF pilots are to be believed, it can potentially make life quite miserable for a Block 50 F-16 or even the F-15 in BVR/WVR combat.

CM

srai · Post by **srai** » 03 Dec 2011 05:03

aharam wrote:...
With heavy class fighters, particularly with TVC, although they can turn and climb very rapidly, I am not sure how many attitude/position transitions they can go through without losing significant energy. Energy is still critical at the end of the day - it is what you can accomplish with a given amount of energy that determines the better plane. ...

...

Cheers
aharam

According the the infamous presentation video of a USAF officer speaking on the topic of Red Flags, Su-30MKIs and F-22 Raptor, he mentioned that if the fighter with a TVC uses it beyond the lift dynamics of the aircraft the plane begins to sink rapidly while pivoting in the air. The opponent fighter seeing this will need to use his energy advantage by pulling up and then coming down for a kill with AAM or guns.

aharam · Post by **aharam** » 03 Dec 2011 05:41

srai wrote:
aharam wrote:...
With heavy class fighters, particularly with TVC, although they can turn and climb very rapidly, I am not sure how many attitude/position transitions they can go through without losing significant energy. Energy is still critical at the end of the day - it is what you can accomplish with a given amount of energy that determines the better plane. ...

...

Cheers
aharam
According the the infamous presentation video of a USAF officer speaking on the topic of Red Flags, Su-30MKIs and F-22 Raptor, he mentioned that if the fighter with a TVC uses it beyond the lift dynamics of the aircraft the plane begins to sink rapidly while pivoting in the air. The opponent fighter seeing this will need to use his energy advantage by pulling up and then coming down for a kill with AAM or guns.

That is the conundrum of fighter performance. These days the focus is on multi-role aircraft. So the weight increases to support the various roles, some of which are as disparate as A2A and A2G. As weight increases, you need a heavier engine with higher thrust. In A2A, while you may have higher thrust, you are not just going straight. Combat maneuvers cause rapid change of position, and in a heavier plane you lose energy very rapidly. Essentially, you are using your engines to change your momentum vector rapidly and for a heavier plane, even the excess thrust is not sufficient to compensate for this. A lighter plane may not have the thrust to do a cobra - beyond a certain AoA, 21 falls on its back

, but the 21 doesn't have the weight either. It can do several rapid rolls in opposite directions without losing a lot of energy and that gives you a lot of options in a dogfight. I believe even the F22 is too heavy to sustain a dogfight against a lighter plane. It can do so against an F15, but the F15 is overweight, so a victory doesn't count for much. Even the F16 started off as a much lighter platform and gained over the years, which detracts from its original design.

A good analogy here is a comparison between two sports cars in a slalom course (windy road). One is lighter, but has a smaller engine and the heavier one has a beefier engine. Both have the same engine HP per ton of weight. Which do you think is going to win a time trial? Even if you made the contest unequal and gave the heavier car somewhat better HP per ton of weight it would still lose on a slalom. It will win a straightaway course, but the constant twists in a slalom decelerate it too much on each turn for it to recover its energy position. A dogfight is a slalom.

Most likely a moot point in today's BVR environment

Cheers
aharam

aharam · Post by **aharam** » 03 Dec 2011 05:48

Cain Marko wrote:
aharam wrote:The Mig 21 certainly belonged to another era of fighter design. Light and agile. I don't know if folks here have read John Boyd's work on maneuverability, the 21 was the epitome of it. The agility of a plane is not just its specs - turn radius, climb rate, thrust/weight ratio. In WVR, it has much more to do with how rapidly you can change the attitude of the plane, for instance changing the direction of a roll. A plane that can rapidly switch from one position/attitude to another without losing much energy holds an advantage in a merge, since it can engage and disengage at will. That was the real fun of a lightweight interceptor. With heavy class fighters, particularly with TVC, although they can turn and climb very rapidly, I am not sure how many attitude/position transitions they can go through without losing significant energy. Energy is still critical at the end of the day - it is what you can accomplish with a given amount of energy that determines the better plane. All of this of course assumes identical pilot skills, which is generally not the case. With most engagements now in the BVR regime, I am not sure if the WVR regime is that important, which is why the 21 is from a different era. Small highly agile light fighters are not there any more and probably not needed in a networked environment where the aircraft is a delivery platform. Even the vaunted F16 is a lot heavier than when it started, and I am not sure it will really keep its edge in the presence of a competently flown 21 in the WVR regime.

Enough with my rambling for now. Would love to hear feedback. The discussions that I have been lurking on have invariably been great.

Cheers
aharam
Well sir, what are your thoughts on the MiG-21 Bison? I believe it still retains its old advantages but now has an HMS and BVR capability. Your bird sir, is still in the fray in today's world. And if the USAF pilots are to be believed, it can potentially make life quite miserable for a Block 50 F-16 or even the F-15 in BVR/WVR combat.

CM

The Bison came just after my time. It retains all of what made the 21 a great aircraft and by adding BVR capability and a modern MFD, makes it easier to use. A HMD is something we couldn't even think about

These capabilities make it more useful in a modern environment, but the aircraft is still an interceptor by design. Against a Block 50, it may be able to hold its own simply due to its small size, which hasn't really increased thankfully. I actually believe the older F16's are probably more deadly in WVR.

Cheers
aharam

Cain Marko · Post by **Cain Marko** » 03 Dec 2011 06:17

The Bison came just after my time. It retains all of what made the 21 a great aircraft and by adding BVR capability and a modern MFD, makes it easier to use. A HMD is something we couldn't even think about These capabilities make it more useful in a modern environment, but the aircraft is still an interceptor by design. Against a Block 50, it may be able to hold its own simply due to its small size, which hasn't really increased thankfully. I actually believe the older F16's are probably more deadly in WVR.

Cheers
aharam

Yes, they did tweak the 21 the best they could under the circumstances. HOwever, there was a rather intriguing upgrade possibility doing the rounds around the same time: A MiG-21 with a MiG-29 engine. SImilar weight/dimensions but more powerful, and better SFC, and less danger of stalling at high AOA. MIght have been nice, however, the supply chain issues with MiG, specifically wrt the fulcrum probly meant that such a deal was unlikely. Also, it might have meant more time in development. Still remains in my favor, at least in the long list of jingo fantasies.

As a pilot yourself, did you ever think of what might be a great way to tinker with the bird you flew? I'd love to hear this in another popular thread on this board - "design/build your own fighter" when time permits of course.

CM

shiv · Post by **shiv** » 03 Dec 2011 06:47

Those are excellent insights aharam, but they set me off into a parallel stream of slightly philosophical thought - having followed the development of military aviation for decades.

The era from the end of WW2 right up to the 1970s was dominated by single role aircraft. The US had their F series fighters and B series bombers and similarly classified "the enemy" (USSR) with "Fishbed" (F for fighter) and "Bear" (B for bomber). Britain too had its own fighter and bomber classifications where the Hunter was "FGA" - Fighter - Ground attack. Unless I am mistaken, only France retained a semblance of a mixed role aircraft that could carry bombs but had guns for self defence.

The cost of aircraft and technology and the need to maintain multiple types led to the demand for "multi-role" or "swing role" aircraft. But it occurs to me that perhaps at least some Western developments were related to the needs of export markets. The USA for instance did continue to develop niche "single role" products for itself like F-15, B-1, B-2, F-117, F-22 while simultaneously developing "popular" stuff for export. Europe could not afford all this. They consolidated and cooperated to produce only multirole aircraft starting from the Tornado. Mirage 2000, EF and Rafale. Their "niche role" requirements were met by the US. Of course in the last decade "multi-ole" has been greatly aided by the development of AESA which is probably the single most important development that enables the "swing role" of sir defence and offence.

India is on a different footing. We have spent decades buying what others have to offer simply because whet we had was not considered good enough to match what Pakistan got. India got jets first (Vampires) but was son overtaken by Pakistan that got the "world's best fighter" the F-86 Sabre and the original widow maker the Mach 2 plus F-104 Starfighter. Byt the time we settled on the MiG 21 and Jaguar, Pakistan got F-16s making us scramble to get multiple types including the MiG 23, Mirage 2000 and later the MiG 29. Just goes to show how much a superpower like the US could make SDRE Indians do a lungi dance by throwing arms/alms at a nearby beggar-whore.

But for the future.. should we stick with mutirole? Or should we too take a leaf out of the gyan that aharam has posted and make dedicated small, agile interceptors and larger dedicated attack aircraft separately? Maybe this is a topic for the "Design your fighter" thread.

Cain Marko · Post by **Cain Marko** » 03 Dec 2011 07:16

shiv wrote:But for the future.. should we stick with mutirole? Or should we too take a leaf out of the gyan that aharam has posted and make dedicated small, agile interceptors and larger dedicated attack aircraft separately? Maybe this is a topic for the "Design your fighter" thread.

At the risk of going OT and being summarily hellphyred, I must admit that I have been thinking that the IAF inventory might include a massive number of LCA 2.0 - geared primarily towards A2A, and short ranged missions. The other more aggressive duties would primarily fall in the hands of the MKI - a very good striker and air supremacy bird, along with the Pakfa (not the FGFA) to blast open enemy doors in enemy territories.

I am not sure where the MRCA fits in at this stage, perhaps in the middle? Frankly, I'd rather see the slot be taken in by a future AMCA and save on the $$s. Buy some force multiplier type assets or even establish a SAM network that is geared towards dealing with 5 gen threats.

In the meanwhile, with large fleets of LCA and MKI, the IAF can split sqds into primary and secondary roles of strike and A2A or vice versa, equipping the birds accordingly. JMT.

shiv · Post by **shiv** » 03 Dec 2011 07:18

Cain Marko wrote:
At the risk of going OT and being summarily hellphyred, I must admit that I have been thinking that the IAF inventory might include a massive number of LCA 2.0 - geared primarily towards A2A, and short ranged missions. The other more aggressive duties would primarily fall in the hands of the MKI - a very good striker and air supremacy bird, along with the Pakfa (not the FGFA) to blast open enemy doors in enemy territories.

I am not sure where the MRCA fits in at this stage, perhaps in the middle? Frankly, I'd rather see the slot be taken in by a future AMCA and save on the $$s. Buy some force multiplier type assets or even establish a SAM network that is geared towards dealing with 5 gen threats.

In the meanwhile, with large fleets of LCA and MKI, the IAF can split sqds into primary and secondary roles of strike and A2A or vice versa, equipping the birds accordingly. JMT.

Not OT at all. This is the "Indian Military Aviation" thread and you are well within those bounds. I am in general agreement with your idea.

bmallick · Post by **bmallick** » 03 Dec 2011 11:42

shiv wrote:But for the future.. should we stick with mutirole? Or should we too take a leaf out of the gyan that aharam has posted and make dedicated small, agile interceptors and larger dedicated attack aircraft separately? Maybe this is a topic for the "Design your fighter" thread.

Shiv sir, why dont we try to debate on the need for a country like ours. We now have actual experience Aharam sir to critically analyse our thoughts and we try to figure out what would be good for us. However a disclaimer is necessary in the sense that a prefessional force like IAF sure knows what it needs better than what we can ever think of. But it would be a good exercise for us.

The main argument put forward for in support of Multi-role fighters is that the can change role quickly and be used for different missions during the same flight maybe or with little changes. So lets say we have a fighter carrying 2-4 bombs and 2-4 AAMs for self defense. However my question is that if while on the way to attack the target it is intercepted by enemy fighters what would it do. To get more agile it has to jettison the bombs and try to fight. But this effectively means a mission kill even if the fighter makes it back home after shooting down an enemy fighter. Some would the say the fighter can fire missiles, shoots the interceptor goes on the drop bombs on the target and returns. But with all dues respect such a thing might be possible if enemy airforce is a couple of rungs down the ladder of yours. Against any decent air-force such scenarios would be few and far in between.

The other option is 2 of this multirole fighter, one loaded with bombs for attacking the target and other with AAMs to defend the attacker. If on the way they are intercepted the AAM loaded one tries to fight and provide a window for the attacker to attack the target and get away. Once that is done the AAM loaded fighter disengages and returns. We might have killed on enemy interceptor during this mission but this would a bonus not the main item. However in this case if one of the multi-role was in the A2A role and the other A2G, then wouldn't we be better off with a dedicated A2A & dedicated A2G in the first place, both optimized for the role intended.

Please note that I know that missions are seldom done by lone aircraft, the above example were just to illustration purpose.

There is another argument put in favour of multi-role that once total air-superiority we just need to pound the ground, hence then the dedicated A2A would by of no use then, but a multi-role can switch to ground pounding. But, doesn't modern software integration of LDP pod do the trick of allowing A2A fighters to drop bombs. Or they can be used to drop GPS/similar guided bombs, pre-fed with target coordinates to hit fixed immobile ground targets.

Morover in our case getting total air-superiority on the eastern front is dream and the airspace there would be hotly contested throughout the length of war. On the western front, we can attain air superiority, but then we do not need 800 fighters to bomb them out. A dedicated number of 200-400 would suffice.

Hence I feel the multirole is over hyped at least in our case. Its too heavy to be hampered in agility as pointed out by Aharam sir and carries too much baggage in term of avionics when its attacking. Its neither completely here nor there. Maybe we would be better served by dedicated role fighters. More-over the multi-role ones are becoming prohibitively expensive to maintain good numbers.

Cain Marko · Post by **Cain Marko** » 03 Dec 2011 12:40

Actually, I doubt anybody makes anything but multirole in today's world. The last "pure" bird in the fighter class was the F-22. Even the Su-34 is equipped for self escort.

Nothing wrong with this perse; but I have a feeling that a/c that are optimized for A2A can be more easily configured for A2G than vice versa. For e.g., both the flanker and fulcrum, which were purely air superiority designs, and even the F-15, have evolved into formidable A2G capable assets. I simply don't see the reverse - not the Jag, not the fencer, not the Hornet, and not the Tornado, and this is despite some very esoteric electronic gimmickry as in the case of the SHornet - still not good enough vs. say a Tiffy or Su-35.

The country that comes closest to making the perfect "Multirole" birds imho, is Fra. Both the M2k and the Rafale are excellent examples. But if India can get a superb A2A design, I think it can be converted into a suitable multirole platform with appropriate avionics, and tinkering. The EF-2K does become more attractive than a Rafale in this sense. As of now, the Rafale might hold more cards, but with proper blockwise upgrades, all/most of that advantage could be leveled. E.g. addition of TVC/HMS will certainly improve EF performance, low and slow. Proper plumbing might give it Rafale's range and a bit of strengthening, equal payload as well. At the same time, it will continue to hold advantage in terms of high altitude performance and larger radar.

IN terms of the AMCA, to which this discussion is probly more relevant, I feel it'd help if those involved aim for a bird with the foll characteristics - mostly geared for air superiority:

1) Large space for big radar ala LCA/EF/Flanker
2) Large volume for massive amounts of fuel
3) Cranked Delta design with large wings and possibly levcons v.similar to LCA
4) Hyper TWR, low drag, low RCS
5) Conformal carriage of A2A weapons, and possibly an internal bay for about 4 AAMs - v.specific roles. Apart from external carriage of strike munitions as well.

The above 4 are bread/butter design goals for the future. It'll set the stage for a v.nice A2A bird; suitable mods can then be made for strike roles.

CM