Design your own fighter

Drishyaman · Post by **Drishyaman** » 05 Dec 2010 14:57

Jeff Wickline wrote:^^ Thanks B_Ambuj (the earlier post) for the criticisms. This kind of criticisms are necessary to debug our thoughts regarding "our" very own designed combat aircraft.

Here, "we" stands for the mango jingo's and not ADA, nor IAF, nor HAL. So this thread can take some liberties regarding the specs. On the other hand we would add real value if we can justify why we took a particular set of requirement.

As we interact and utilize our dialectics, our specs would get refined, hopefully.
IMHO nobody would tell us the detailed rationale behind GSQR or ASR, or whatever is the sacred specs. We would develop our own argument in this process and may even be able to decode the intent behind the ASR.
It is quite possible that seniors might know the exact reasons behind a particular choice of an ASR but us, lesser mortals need to learn through this process.
So please help refine the specs or requirements. I just thought it unacceptable that even after 240 posts, we are unable to define the problem. Let us start with an imperfect and half-baked idea and shape it up as we go. Please continue your contributions.

Regarding the Long Range bomber, from the trend it just appeared to me that days of such huge aircraft are possibly numbered. But that is just a personal opinion onlee. I am sure it is fairly easy to figure out the respective complementary roles of missiles and aircraft.

Jeff, Thank you for accepting my views in a positive way.
Fully agree with you, we need to refine our specs and by discussing with each other we can refine our thought.

As of Long Range Strategic Bomber’s days being numbered, not sure about that as Russia is still designing PAK-DA and Unkil Sam is still using B-2 and B-52.
But, if you talk about cost and affordability, there is a big question now but who knows 20 yrs down the line may be we can afford that.
But, at least we can go to the drawing board now ?
20 yrs later, if we realize that we have a need for Long Range Strategic Bomber and then try to go in for designing the same, may be we will be too late by then ?
Need to give a thought on that, what do you say ?

Seems like you are from the North-east, originally me too but not currently:)

Jeff Wickline · Post by **Jeff Wickline** » 05 Dec 2010 15:18

If we get enough participants with some free time, we can certainly start a new thread "designing our strategic bomber". It would be an interesting exercise with choice of airframe, engine etc. Have to be stealthy as well. It would not cost the nation much as "we" would be doing it in our free time.Cheers.
P.S. I am in north east with respect to Bangalore and south west with respect to Lhasa.

manish.rastogi · Post by **manish.rastogi** » 06 Dec 2010 01:04

jeff sir.,...would surely contact you when needed for the book....btw jeff and b_ambuj sir i sometime back posted a jet and bomber design...the specs were very basic....but i still think it has some quite good innovations.....the jet and bomber had a lot of commonality.....

My suggestion would be that currently we are just discussing...i say we start doing the designing properly....with setting the timeframe and basic asr for it....and instead of looking at other aircraft designs...we start doing it our new and innovative way....
Thanks...

shiv · Post by **shiv** » 06 Dec 2010 06:12

Personally I think the way to develop ideas about aircraft design is not via books but by encouraging children to build model aircraft that fly. Building one model that flies will teach a person a hundred different things that should not be done - a hundred things that will ensure that the model does not fly well and a dozen things that make it fly. If give a hundred thousand children the gift and joy of aeromodelling - at least 10 of them will learn more about building real aircraft in later life and one may even become a leading designer.

Design and engineering are essential in aircraft, but there is an art out there as well.

shiv · Post by **shiv** » 06 Dec 2010 06:45

Jeff Wickline wrote: 3. Twin canted Radavetors permit (i) to reduction of RCS by geometry and reduction of metal component (ii) extra pitch moment if requited.

4. Canards have not been totally ruled out at this stage. We have to see whether the advantages it provides would be required for the envisaged role of the aircraft.
5. As regards tail, i thought it looks nicer and easier to size up in first design. However, if we want to use the same hydraulic actuators as in Tejas, we may have to revise our choice.

I think we need to get back to basics. An aircraft is a a machine that is supposed to fly. The questions I am asking revolve around the following facts:

The Gloster Meteor and The HJT 16 are flying machines. Both have flown and the latter continue to fly. Both were cyinders with wings. Only the Metor carried its engines on its wings. The Kiran does not. They flew because of wings. But why did both have a tailplane? Why do both not have canards? Why do both have tailfins? Tailplanes are not needed. But they are useful. They are useful for pitch control. Since the plane needs to be controllable, pitch control from a point that is far away from the center of mass is useful. Again - since the tailfin is needed for control in the yaw axis. These points are considered as "obvious" but they are actually not so obvious when you can fly aircraft with no tailfin and no tailplane.

Going one step up, the MiG 29 and the F-15 are similar to the Gloster Meteor. They have a mainwing and a tailplane. But the have twin vertical tailfins. (slightly canted in MiG 29) Why two tailfins? Why do they have nearly vertical tailfins and not canted tailfins?

Go up one more step and look at the at the F-35. Again it has a mainwing and a tailplane, just like the Gloster Meteor and the Me 262. But twin fins? Why? They are canted of course - far more so than the minimal cant angle of the MiG 29. But why two? After all high performance aircraft like the Eurofighter Typhoon, the Rafale and even the MiG 29 seem perfectly happy with one tailfin. Why two?

Back to talking about the tailplane:
Me 262, Gloster Meteor and F-35 - have a tailplane
Viggen, Rafale, Eurofighter - have canards and no tailplane.

The Su 30 MKI is a freak aircraft. It has a tailplane AND canards AND thrust vectoring. I think the MKI design is not relevan to this discussion because of thrust vectoring

Finally look at the B2 bomber. No tailplane. No tailfin. No thrust vectoring.

Why do we make design choices? Why choose two tailfins over one? Why choose tailplane? Why not canard? Why think that "canards may be needed in addition to tailfin" if we do not know why they are there in the first place? What is the problem in just building a flying wing which is stealthy by the absence of things sticking out?

If one is going to design a plane (and not a helicopter), wings are essential. Onc you have wings you need to ask whether those wings will look like Me 262 wings, of HJT 16 wings, or MiG 21 wings or F-22 wings. And why do you need a tailplane? Why do you need a tailfin? Why would you need canards?

These are basic questions in making a machine that flies. We CANNOT talk of payload, stealth and range before answering basic questions. If we take the basic questions for granted we are "assuming things" just like GTRE assumed that Kaveri could be done soon or ADA assumed that FBW could be done soon for a pure delta. And both GTRE and DRDO consisted of engineers who already knew why an aircraft design should or should not have a tailplane or tailfin. The flying and control surfaces of air aircrfat are fundamental to the aircraft. They have to be decided first and there have to be valid reasons for the choice. Or else we should build a Gloster Meteor.

Jeff Wickline · Post by **Jeff Wickline** » 06 Dec 2010 12:42

^^ Very pertinent questions and difficult too, Shiv Saar.
I think I can now (after the last post you have quoted) would be able to answer some of these.
Unfortunately, I am on my way to airport and would not have net-access for three days. (Would you believe it, in 2010?). More importantly, I would not have access to the required books. So meanwhile, let other posters also react.
On my return I plan to post the outline of the adopted design cycle and the points in time when to consider each of the factors mentioned.
In my novice scheme of things, I start with the payload, range and constraints for the conceptual design. The wing design and fuel weight come fairly easily. Then comes the difficult bit. The CG and CP variations over the full operating envelope, which would give clues regarding the choice of tail control, canard or both.
At this stage, I feel a twin Radavetor is the preferred choice. I would revise it only after I get preliminary numerical results.
Friends who would like to go through this laborious numerical-logical exercise, please post a line.
Again a BIG thank you to Shiv saar for putting us into this exciting adventure.

manish.rastogi · Post by **manish.rastogi** » 06 Dec 2010 13:04

i am in....but you guys have to give me work which i would be able to do....

Bala Vignesh · Post by **Bala Vignesh** » 06 Dec 2010 21:19

So am i...
BTW.. what about resuming the design from the earlier posts in the thread based on the inputs from Abhibhushan sir...

Rahul M · Post by **Rahul M** » 06 Dec 2010 23:17

here's my fantasy fighter, based on LCA Mk1. meant for CAS and limited strike capability.

let's call it the Tejas Mk1S, S for Strike.

differences with tejas Mk1.

>> multi-mode radar in nosecone replaced with a smaller terrain following radar with ground imaging capability, FLIR, LRF and target designator. I expect NV capability is already there.

>> cockpit encased in armour plates to protect the pilot from ground fire. similar armouring applied to other critical areas like hydraulic lines, fuel pipes etc.

>> autopilot mode for terrain following flight.

>> payload reduced to 1.5 tonnes to cater for the increased armour protection. this is in addition to internal fuel, missile pylons, gun ammo and 2 WVR missiles.

>> number of rounds for Gsh-23-2 increased from 220 to 500

typical weapon profile for various roles :

>>anti-tank
upto 9 X Nag ER, nag missile derived ATGMs for use on fast jets. (total weight approx. 450 kg) carried on multiple missile racks mounted on centreline and inner pylons,
2 X R-73 or self-defence close combat missile in same class mounted on wingtip pylons
2 X 800 external litre fuel tank if necessary. (at the cost of two Nag ER missiles)

>> SEAD
2 X R-73
2 X KH-31 or similar (approx 600 kg each)

>> CAS
2 X R-73
4X 250kg

manish.rastogi · Post by **manish.rastogi** » 07 Dec 2010 02:25

sounds good sir....but dont you think the strike aircrafts must be quite stealthy!!

negi · Post by **negi** » 07 Dec 2010 03:13

^ It is meant for CAS on battlefield i.e. enemy more often than not won't have luxury of a powerful ground based radar or even AWACS, it would at most have some short/medium range SAM or AA guns. Btw to be realistic the only way we can come up with a inhouse engine in next 2-3 years to power such an AC is by doing some 'badmashi' with our contracts and making a desi version of the Adour Mk 811.

Bala Vignesh · Post by **Bala Vignesh** » 07 Dec 2010 08:28

^^ Negi sir, while we are at it we might as well do it with the RD33mk3... Better engine and in the class of kaveri, if i am right...

negi · Post by **negi** » 07 Dec 2010 08:43

^ Well HAL Koraput's page says we as of now only overhaul the RD-33 series. I might be flogged for saying this but it's high time we start to 'appreciate' the need to 'reverse engineer' one has to think about it holistically keeping hollow H&D aside , I am often amused at yankies and even ruski fan boys making fun of Cheenis about reverse engineering not that I am complaining but the fact is former have themselves indulged in the same at some point in the past (it is for everyone to see as to how both US and RU benefited from whatever was left of Nazi Germany's MIC). We have been license manufacturing Adours since 1981 the question I often ask myself is why didn't we think of taking one of them apart and make a similar one with raw materials in desh (it doesn't use SCB or fancy stuff like hollow fan blades ) and is far simpler in design when compared to Kaveri , once done we could have built upon that and produced uprated versions of the same by tinkering around with relevant variables no it might not have powered the Tejas or any 4th gen fighter but could be used in a jet trainer hell if nothing else we could use the uprated versions to power our HAWKs and even upgrade the Jags.

vardhank · Post by **vardhank** » 07 Dec 2010 08:59

Rahul M wrote:here's my fantasy fighter, based on LCA Mk1. meant for CAS and limited strike capability.

Nice, and eminently doable, I think. One problem though: AFAIK, delta wings aren't the best for low-level combat - too much wind-buffeting. Can that be compensated for with changes to the FBW system?

Bala Vignesh · Post by **Bala Vignesh** » 07 Dec 2010 09:30

Negi sir,
The wiki page for RD33 says india is going to license manufacture the Mk3 version of the engine in HAL. This opportunity, IMVHO, must be used to learn and carry out RE as much as possible. And, i am ballparking here, the russians wouldn't have much to complain considering their reactions to the chinese.

Added later- But sir, i accept your point of choosing the Adour, considering the number of years we've been working on it and with it.

Rahul M · Post by **Rahul M** » 07 Dec 2010 09:46

vardhank wrote:
Rahul M wrote:here's my fantasy fighter, based on LCA Mk1. meant for CAS and limited strike capability.

Nice, and eminently doable, I think. One problem though: AFAIK, delta wings aren't the best for low-level combat - too much wind-buffeting. Can that be compensated for with changes to the FBW system?

with FBW FCS that is no longer a problem.

negi, why would we need any other engine ? we can use the F404IN20 itself.

manish, this kind of aircraft is used to directly support army columns on ground, against similar enemy formations. they will operate after the skies have been relatively sanitised by SEAD aircraft and under the air cover from fighter flying CAP. limited SEAD might be possible of course. and btw, the LCA RCS is quite a bit smaller than most contemporary fighters.

negi · Post by **negi** » 07 Dec 2010 09:48

^ Bala I know that we had signed the contract with RU to license manufacture the RD-33 MK3 in India (inter Govt agreement was signed in 2007 but the deal was formalized during MAKS 2009 ) but taking into account the nature of product in question I would presume it would take some time for first RD-33 MK3 to roll out from Koraput.

negi · Post by **negi** » 07 Dec 2010 09:51

Rahul if my understanding of Shivji's problem statement is correct (first post on this thread) then I wonder if F404IN20 qualifies.

Rahul M · Post by **Rahul M** » 07 Dec 2010 10:59

ah, I (conveniently) forgot about that condition. never mind, we will use the kaveri as it exists now.

vardhank · Post by **vardhank** » 07 Dec 2010 12:08

with FBW FCS that is no longer a problem.

Haan kya? Awesomeness

Anybody listening out there?

Jeff Wickline · Post by **Jeff Wickline** » 10 Dec 2010 11:53

^^ Hi everybody,
No posts during past three days! Let us continue. BTW what is "Awesomeness"?

But first, thanks to the volunteers:

manish.rastogi wrote:i am in....but you guys have to give me work which i would be able to do....

Bala Vignesh wrote:So am i...

Sorry friends, didn't have 'net access and could not respond. We would certainly share the workload, but to start with we should do something together. Action point-1. Try google uncle with the keyword, within quotes "combat aircraft design". Most likely, that in the very first page, we would get "Conceptual Design and Optimisation of Modern Combat Aircraft", a 1999 paper by C A Crawford and S E Simm of the now defunct DERA, a lean and mean British DRDO. (DERA has since been privatised with a new name like quinitek or something.) This paper would be useful. Promising that other similar action points would follow.

May I humbly suggest that at this stage posters to this thread please take one of the following roles:
A. Mentors: Shiv Saar, Rahul Saab et al, who would advise the design team and provide corrective feedback.
B. Users: Members who have knowledge about the USE of this or similar combat aircraft and tactics and continue to provide their wish list. These group should also suggest the kind of weapons and sensors that would be useful for the envisaged duty.These members would interact and argue with the mentors to filter such wishlist into fesible set of functionality specifications. Being users, these members should not impose solutions like why not three engines, one engine, delta wing, tail or tail less etc.
C. Members without portfolio (aka members at large). No explanation necessary. They would keep the thread alive.
D.The designers. Favourite whipping boys of B and C Groups. Would try to jot down or derive specifications and propose (quantitative/qualitative) preliminary design solution, within the constraints given in the first post and subsequent clarifications in this thread. This group should periodically report design progress so that the design may be criticized by others.
Cheers.

Jeff Wickline · Post by **Jeff Wickline** » 10 Dec 2010 12:03

^^ some suggested ground rules.
1. Mentors, from time to time may assume the role of Users.
2. Designers should not argue with "members at large", from the "conservation of energy principle".
3. Designers may seek clarifications from the users and mentors but not argue with them.
4. Designers should use only public domain information.

Pratyush · Post by **Pratyush** » 10 Dec 2010 12:08

Rahul ji,

whats with Yindians thinking SDRE onlee.

1.5 tons of warload. Go for at least 4 tons also it give more options to the strike platform. The reson being not every thing deserves an ER NAG. Some times the enemy must $hit in his pants. That means some thing bigger like a 1 ton bomb.

MOAB is preferrable but our design will not be able to carry it.

Shock and awe onlee.

Bala Vignesh · Post by **Bala Vignesh** » 10 Dec 2010 18:05

Jeff sir,
No matter what we do, whatever we come up here stays as an theoretical design, unless we flight test atleast a model aircraft.. any ideas on that???

Or should we be just design the bird on paper be satisfied like the babus that govern us..

Rahul M · Post by **Rahul M** » 10 Dec 2010 18:18

Pratyush wrote:Rahul ji,

whats with Yindians thinking SDRE onlee.

1.5 tons of warload. Go for at least 4 tons also it give more options to the strike platform. The reson being not every thing deserves an ER NAG. Some times the enemy must $hit in his pants. That means some thing bigger like a 1 ton bomb.

MOAB is preferrable but our design will not be able to carry it.

Shock and awe onlee.

pratyush ji, I kept strictly within the confines of the LCA Mk1 capabilities, so as to make this as realistic as possible. with additional armour its payload will decrease to those levels.
a normal LCA squadron can operate one flight of this variant without creating problems in maintenance.

for MOABs (

) we will use MKI's and the like. this one is meant strictly for close air support or CAS. strafing and bombing enemy troops and vehicles in front of IA units as they move.
for other roles it can carry rockets and 250 kg PGMs.

Jeff Wickline · Post by **Jeff Wickline** » 10 Dec 2010 19:59

Bala Vignesh wrote:Jeff sir,
No matter what we do, whatever we come up here stays as an theoretical design, unless we flight test atleast a model aircraft.. any ideas on that???

Or should we be just design the bird on paper be satisfied like the babus that govern us..

Vignesh Sir,
With our resources, for the time being, we may have to be satisfied with a paper design only. "Flying" a balsa wood model is not a big issue. This can be done with some CG management (to force stability) as most combat aircraft AFAIK are unstable and are not flyable without a flight controller (DFCC). We won't gain much by that. We may, later, with the help of resourceful BRFites however, (i) get a CAD design, (ii) try to make a wind tunnel model by the so-called Rapid Prototyping and (iii) get the same tested in some educational institution. (iv) Some resourceful members may also try a Computational fluid dynamic studies.
But these are all in the future. Just now let us go ahead with the "conceptual design".
In this or the AMCA thread, I think Rahul sir mentioned the book, "Aircraft Design a Conceptual Approach", by D P Raymer. Raymer proposes the three phases of "paper design", namely Conceptual, Preliminary, Detail. The CAD model would come only after the Detail design phase.
In my novice estimate, if we can achieve the conceptual design completed and more or less accepted by this thread within 3 months, that would be great.
Cheers

Jeff Wickline · Post by **Jeff Wickline** » 10 Dec 2010 20:03

A few questions to the mentors:

1. Is the use of M/c guns for air to ground is still in vogue? Or is the role of gun is limited as a self defence against hostile aircraft. We thought A2G rockets are more in vogue.

2.With the prevalence of MANPADs like FIM-92 Stinger,Thales Starstreak, 9K38 Igla et al, would the next generation attack aircraft fly below 6000m? If not, what kind of A2G would be used? Would armouring be mandatory in that case?

Rahul M · Post by **Rahul M** » 10 Dec 2010 20:19

what is the most common CAS platform type of our era ? attack helicopters ?
all attack helos carry cannons except one model of the tiger, which too can fit external gunpods if needed.
I don't suppose I've to mention the su-25 or the A-10.

strafing continues to be very potent against all kinds of military targets except MBTs.
APC's, soft skinned vehicles and of course individual soldiers are pretty vulnerable. A2G rockets are popular as well but not at the expense of guns. unguided rockets are used to target stationary high value targets. but you can only hit a couple of targets per sortie. guns allow more flexibility in response in tackling a wide variety of targets.

Jeff Wickline · Post by **Jeff Wickline** » 10 Dec 2010 20:25

Rahul M wrote:what is the most common CAS platform type of our era ? attack helicopters ?
all attack helos carry cannons except one model of the tiger, which too can fit external gunpods if needed.
I don't suppose I've to mention the su-25 or the A-10.

strafing continues to be very potent against all kinds of military targets except MBTs.
APC's, soft skinned vehicles and of course individual soldiers are pretty vulnerable. A2G rockets are popular as well but not at the expense of guns. unguided rockets are used to target stationary high value targets. but you can only hit a couple of targets per sortie. guns allow more flexibility in response in tackling a wide variety of targets.

In view of the above, we take gun as a mandatory weapon. This aspect of spec is then frozen. Though a GAU-8 type gun would consume lot of chin space and would contribute to the weight.

Rahul M · Post by **Rahul M** » 10 Dec 2010 20:57

2.With the prevalence of MANPADs like FIM-92 Stinger,Thales Starstreak, 9K38 Igla et al, would the next generation attack aircraft fly below 6000m? If not, what kind of A2G would be used? Would armouring be mandatory in that case?

good question.

the answer again depends on the adversary's AD potential. if he has mainly low level AD weapons like stingers you will want to go in at high altitude. but what if he has both low level SAMs and long range high altitude capable SAMs like S-300 et al, like PLA does ?

which one would you rather face, stingers or S-300 ?

the threat to missiles like stinger to well armoured aircraft is not as high as is generally believed (but considerable nonetheless). su-25's have been known to survive stinger strikes on their tailpipes and able to return even when damaged. it is not easy to manually target a fast moving jet in a few seconds, even with good early warning especially if you are under fire !

bmallick · Post by **bmallick** » 10 Dec 2010 21:13

With regards to Manpads, Rahul sir, since modern IR sensors on missiles are all aspect , should we still go for a design where the jet exhaust are hidden from view, specially when viewed from the ground. Also would a hidden from view exhaust means IR sensors would have difficulty if the jet is coming from an angle such the the sun is behind it. Please note that when I say hidden from view, I am not proposing some exotic solution like the F-117 or its ilk, but something simpler like having a low wing , which is long at the roots and engine are placed above the wing such that the exhaust are shielded from view by the wing root section.

Also as Shiv sir said that since India may not have sufficient resource luxury to have a dedicated CAS aircraft, why not make a Jet which can do both CAS, Interdiction & deep Strike. A deep strike jet would require substantial fuel capacity, which would also means that during CAS mission it would have enough fuel for longer loitering. Jeff what do you say?

Jeff Wickline · Post by **Jeff Wickline** » 10 Dec 2010 22:29

manish.rastogi wrote:btw jeff and b_ambuj sir i sometime back posted a jet and bomber design...the specs were very basic....but i still think it has some quite good innovations.....the jet and bomber had a lot of commonality.....

@Manish i was trying to locate your earlier post but could not . Can you please help me out?

manish.rastogi wrote: My suggestion would be that currently we are just discussing...i say we start doing the designing properly....with setting the timeframe and basic asr for it....and instead of looking at other aircraft designs...we start doing it our new and innovative way....
Thanks...

So Manish, you had really charted the way to go. Just wished to record this. Hope we are on your desired track.

Jeff Wickline · Post by **Jeff Wickline** » 10 Dec 2010 22:57

Bala Vignesh wrote:So am i...
BTW.. what about resuming the design from the earlier posts in the thread based on the inputs from Abhibhushan sir...

@ Bala, following your suggestions, I am summarizing the earlier inputs from Abhibhushan sir. The numbering in bold added. Retained only the requirement part.

Abhibhushan wrote: 1. I want to take a detour and come up with some thing that my pongo friends would love to see in the sky.... ... I need an aircraft that can operate over Wallong and Along and perhaps a hundred kilometres north of it for releasing weapons in marginal visibility and if possible even by night.
2. I need an aircraft that will take off from Leh or Chshul with one and a half tons of ordnance and be able to operate comfortably with full load at 20000 feet or more.
3. I want an aircraft that can have a radius of action of 200 km flying at 15000 feet above sea level.

4. Give it a light contour mapping / imaging radar slaved to an HMS.
5. Replace the 2 machine guns of the Kiran Mk 2 with one GSh23.
6. Give it a glass cockpit and a DARIN III fit. (Glass cockpit no problem, LCA has it. We have to get weight and internal volume data for DARIN)
7. Give it an integral laser target designator.
8. See if the RCS can be reduced.
9. If possible, give it one or two short range light air to air missiles carried over the wing like the Jaguar. Give it a self defence electronic suit.
10. PS. I do not foresee a dense air defence air presence in the projected hostile area. If one comes along, I shall need top cover by the air dominance fighters you all are designing.

I think the specs are converging.
If we extend the requirement number 10, should we also assume that long range SA are somehow absent?

Rahul M · Post by **Rahul M** » 10 Dec 2010 23:04

bmallick wrote:With regards to Manpads, Rahul sir, since modern IR sensors on missiles are all aspect , should we still go for a design where the jet exhaust are hidden from view, specially when viewed from the ground. Also would a hidden from view exhaust means IR sensors would have difficulty if the jet is coming from an angle such the the sun is behind it. Please note that when I say hidden from view, I am not proposing some exotic solution like the F-117 or its ilk, but something simpler like having a low wing , which is long at the roots and engine are placed above the wing such that the exhaust are shielded from view by the wing root section.

please drop the sir !!

while modern IR sensors are evolving, MANPADS have limited space and weight to incorporate those capabilities. consequently MANPADS significantly lag A2A missiles in sensor sensitivity. also, in a couple of decades we are going to see DIRCM on fighters (they are already being made for transports and helos) reducing their effectiveness even further.
however, simple modifications like the way you mention are almost always useful provided that doesn't skew your other requirements of the platform.

Also as Shiv sir said that since India may not have sufficient resource luxury to have a dedicated CAS aircraft, why not make a Jet which can do both CAS, Interdiction & deep Strike. A deep strike jet would require substantial fuel capacity, which would also means that during CAS mission it would have enough fuel for longer loitering.

that is why I was talking of a minimally modified LCA for the job and not a dedicated CAS aircraft.

it would share virtually everything with the vanilla tejas except the radar and a couple of sensors. no reason why it can't be operated as part of a regular LCA Mk1 squadron itself. it won't need a whole new
many air forces do operate specialised aircraft as part of their regular squadrons, especially in those countries that make their own aircraft.

Rahul M · Post by **Rahul M** » 10 Dec 2010 23:06

Jeff Wickline wrote:
Abhibhushan wrote: 1. I want to take a detour and come up with some thing that my pongo friends would love to see in the sky.... ... I need an aircraft that can operate over Wallong and Along and perhaps a hundred kilometres north of it for releasing weapons in marginal visibility and if possible even by night.
2. I need an aircraft that will take off from Leh or Chshul with one and a half tons of ordnance and be able to operate comfortably with full load at 20000 feet or more.
3. I want an aircraft that can have a radius of action of 200 km flying at 15000 feet above sea level.

4. Give it a light contour mapping / imaging radar slaved to an HMS.
5. Replace the 2 machine guns of the Kiran Mk 2 with one GSh23.
6. Give it a glass cockpit and a DARIN III fit. (Glass cockpit no problem, LCA has it. We have to get weight and internal volume data for DARIN)
7. Give it an integral laser target designator.
8. See if the RCS can be reduced.
9. If possible, give it one or two short range light air to air missiles carried over the wing like the Jaguar. Give it a self defence electronic suit.
10. PS. I do not foresee a dense air defence air presence in the projected hostile area. If one comes along, I shall need top cover by the air dominance fighters you all are designing.

wow, fantastic, my pet LCA Mk1S seems to be written for this set of 'ASR', right up to the payload !

and I didn't even remember this post when I typed that post.

AWMTA !!

Jeff Wickline · Post by **Jeff Wickline** » 10 Dec 2010 23:29

Rahul Sir,
^^ This prompted me to comment that "specs are converging".
We now have to sub-threads of solutions.
Thread#1: Modify the Tejas into an attack version, as you have suggested in an earlier post. This requires serious deliberations.
Thread#2: Nuby jingos like the undersigned and Manish, who have never designed an aircraft ab initio would like to try our hands. Modifying Tejas would not satisfy this goal. We would like to design. Consider this as a self inflicted initiation ritual. Hope the seniors would bear with us.
As and when one or both these streams gain momentum, I hope the mods would arrange for fresh threads.
Jeff

Rahul M · Post by **Rahul M** » 10 Dec 2010 23:55

thank you for posting that but please drop the sir.

manish.rastogi · Post by **manish.rastogi** » 11 Dec 2010 13:40

actually currently i am on mobile.....i promise to work with full dedication as i get my hands on my computer tomorrow.....and jeff sir i would repost it tomorrow....
Thank you....

Bala Vignesh · Post by **Bala Vignesh** » 11 Dec 2010 14:59

Jeff Wickline wrote:
Abhibhushan wrote: 10. PS. I do not foresee a dense air defence air presence in the projected hostile area. If one comes along, I shall need top cover by the air dominance fighters you all are designing.
If we extend the requirement number 10, should we also assume that long range SA are somehow absent?

Sir,
What abhibhushan sir says here is that there would not be a significant presence of fighters for air defence and not about SAM threats...
I envisage atleast a tunguska type mobile air cover for the enemy logistic and armor convoys. Presence of long range SAM's is slightly. JMO.

Jeff Wickline · Post by **Jeff Wickline** » 11 Dec 2010 15:14

Bala Vignesh wrote: Sir,
What abhibhushan sir says here is that there would not be a significant presence of fighters for air defence and not about SAM threats...
I envisage atleast a tunguska type mobile air cover for the enemy logistic and armor convoys. Presence of long range SAM's is slightly. JMO.

Vignesh, in that case, we have to assume that one of the missions of the envisaged attack aircraft would be to make the enemy radars inoperative. One has to make room for such weapons and corresponding LRU.
Don't know about tunguska though, have to read a bit and report back.
Jeff
PS. Please drop the Sir. How about comrade?

Added later: Browsed Tunguska in Wikipedia. The tracking radars look too small. Have to find suitable weapon to de-activate these cuties.

Added later: Learnt that Anti Radiation Role is also known as Wild Weasel mission and currently F-16 are equipped to handle this. A rough calculation shows that for a 30 km standoff with a passive radiation seeker and INS-GPS, a single round would weigh about 40kg. With about 15m circular miss distance a kill probability of 60% seems likely. Supporting electronics on board, do not know, but would assume 40 kg mass.