India to build its own stealth fighter jet.

[faithfulguy]

Man first check your Tejas

I'm still trying to figure out why India named a plane after the great state of Texas in Spanish.

 

[Dalai Lama]

I'm still trying to figure out why India named a plane after the great state of Texas in Spanish.

TEJAS is a sanskrit name that is used by most gujaratis and the meaning of this word is luster/ radiant energy / fire.

What does tejas mean

 

[indianspetsnaz]

We respect your view, But if you follow the LCA thread you will come to know, what cause the delay and what could be rectified in case of AMCA... Just look on these points..

1. Do we need to make huge infrastructure what we made in case of LCA, or we can use the LCA infrastructure to make/test AMCA???
2. Will the massive experience gained in developing LCA help AMCA ?? or won't it??
3. ALH dhruv took many years to developed, LCH took less than half of its time, Won't this happen in case of LCA and AMCA??
4. Will the experience gained in PAK-FA be useful for AMCA or won't it??


Likewise there are many points, If you think logically, you may be little optimistic...

well the 2 primary factors for LCA delay was because of technology embargo due to sanctions after 98 nuke tests and economic crisis in early 90's which caused funding to be ceased

i doubt those 2 thing would happen again but building a 5th gen fighter jet when we have not even completed our 4th gen fighter first is quite a long shot but LCA MK2 is there for IAF to match modern capabilities

one thing we really need to do is combine ADA with HAL so they work together on AMCA HAL can share its experience with ADA and whatnot

 

[RusoIndian]

Livefist: The Stealth In India's Advanced Medium Combat Aircraft (AMCA)

With aerodynamic design optimisation near complete, the AMCA's broad specifications are final. The aicraft will have a weight of 16-18 tons [16-18 tons with 2-tons of internal weapons and 4-tons of internal fuel with a combat ceiling of 15-km, max speed of 1.8-Mach at 11-km. The AMCA will be powered by 2 x 90KN engines with vectored nozzles. For the record, the official ADA document that will finally be processed this year by the government towards formal project launch describes the AMCA as a "multirole combat aircraft for air superiority, point air defence, deep penetration/strike, special missions

IMO i think the service ceiling for the AMCA should bee AT LEAST 18km (59,000) feet and it should be able to reach Mach 2 and have engines that can produce 100kn of thrust with afterburner (just my opinion) if this is what the IAF wanted then i guess its best for them

 

[sancho]

IMO i think the service ceiling for the AMCA should bee AT LEAST 18km (59,000) feet and it should be able to reach Mach 2 and have engines that can produce 100kn of thrust with afterburner (just my opinion) if this is what the IAF wanted then i guess its best for them

What for when you have these (in customised versions) as well?

http://www.defence.pk/forums/india-defence/118201-su-pak-fa-fgfa-18.html

The same reason why EF next to MKI, with the same capabilities makes not much sense. If at all AMCA must offer us something that the FGFA don't have, or can't do and so far, there seems to be not much difference and that's why India don't need 2 similar 5th gen fighters.

 

[RusoIndian]

What for when you have these (in customised versions) as well?

http://www.defence.pk/forums/india-defence/118201-su-pak-fa-fgfa-18.html

The same reason why EF next to MKI, with the same capabilities makes not much sense. If at all AMCA must offer us something that the FGFA don't have, or can't do and so far, there seems to be not much difference and that's why India don't need 2 similar 5th gen fighters.

just saying most 5th gen fighters have service ceilings well above 59,000 feet like F-35 F-22 PAKFA etc and there engines produce thrust of 100kn or more with after burner

AMCA will be a true multirole fighter but i hope it does not have the thrust to weight issues the LCA is currently plagued with

 

[AgnosticIndianNationalist]

its ambitious plan but i hope it does not become delayed for 30 years like LCA did, 2025 better not become 2055

 

[gambit]

However is the target is manuevering, lets say both lazy and evasive?, does that reflect the same RADAR signature (im sure not).

You are correct. Radar cross section (RCS) values of a complex body changes with respect to the viewer. An appropriate analogy is that you see a different part of a car as you do your 'walk-around'. The only body that has a constant RCS regardless of perspective is the sphere.

Then how does the entire cluttre detection system works in accordance with the approaching fighter's RCS?

Not clutter detection but clutter rejection. I will try to understand your question and answer accordingly...

In the initial stages of radar identification (detection) of an object, EVERYTHING is detected. Then the majority of those signals are compared against a table of known signals (electrical characteristics) that we do not want to send to video integration (display). That table is called 'clutter rejection' and we can add or remove signals as we wish, even on the fly. That is called 'clutter rejection threshold'.

The few remaining signals that are above this threshold are sent to the next stage where much more complex algorithms begins to work on discrete elements of these signals. For example, if the radar is looking 'up' we know we are not looking at the ground with its features like hills, cluster of plants, moving animals, flying birds, etc...So we lower the clutter rejection threshold by removing electrical characteristics that matches 'hills, cluster of plants, moving animals, flying birds, etc...' from that table. It can be like a loop if the radar is alternating between looking 'up' or 'down'.

So if we are looking 'up' and therefore we are looking at relatively 'empty' or an electrically speaking 'calm' background, any complex body that is radiating EM signals will appear as a cluster and the cluster will look like this bit of a mess...

These complex algorithms have their own complex tables to work this cluster against. For example, we know that that the complex body known as an 'aircraft' has certain physical structures that will be common to most aircrafts out there, such as a vertical stabilator all the way to the rear of the body, two horizontal stabs at the same location, a cavity (exhaust) at the same location, and so on...If this cluster exhibit electrical characteristics that are within a certain statistical range of a table, then the radar computer will flag this cluster as a 'valid' target and send it to video integration (display).

Now we have a problem if the radar is looking 'down' meaning at the ground with its 'hills, cluster of plants, moving animals, flying birds, etc...'.

The goal of video integration is to display something that is meaningful to the 'meatbag' that is sitting in front of the display......The radar computer is essentially saying: 'What a moron this meatbag really is. I have to clear up so much crap just so the moron can understand what is in front of him.'

So if there are 'hills, cluster of plants, moving animals, flying birds, etc...' that are in the system, it can be very difficult display the complex body called 'aircraft' in a meaningful manner. So the system loop back to the first stage, cranks up the clutter rejection threshold, and process any cluster of signals that is above this threshold. Remember, this cluster of a complex body is ALWAYS there, only now that it is being surrounded by many other clusters. But because it is surrounded by other clusters, it can be very difficult to mark this cluster as an 'aircraft'.

The radar computer's thought process goes like this:

- We have a cluster of electrical signals.

- We see that the cluster is above the clutter rejection threshold.

- We see that the cluster's individual electrical characteristics matches a table labeled 'aircraft'.

- We will mark this cluster as 'aircraft' and send it to display so the meatbag can understand what the hell are we seeing.

This is why military aircrafts have this tactic of using the Earth as an electrical cover just in case they are being hunted by a radar looking down. There are no guarantees that this cover will work, but air combat history proved that the odds of survival increases when the tactic is employed in many situations.

How does the RCS reduction works here?

RCS reduction methods tries to insert the cluster into the clutter rejection threshold even if the radar is looking 'up' or against relatively electrically 'calm' background. The nose-on aspect is always the lowest RCS value, but if it is above the 'calm sky' clutter background, that RCS value will be flagged. If it is below that 'calm sky' clutter background, it will not be flagged. Now add the Earth's electrical mess into the mix, then the 'stealth' aircraft is practically 'invisible'. This is why radar systems prefers to look 'up' whenever possible.

This is why 'stealth' aircrafts are such threats: They are usually automatically inserted into the lowest clutter rejection threshold by most radar systems.

 

[AgnosticIndianNationalist]

so if the AMCA with full payload max fuel comes out to weight 25ton(with everything) and it is powered by 2 90kn (dry thrust) engines what would its thrust to weight be?

and and if its after burner was say some where between 120-150kn what would the thrust to weight come out to be?

we need T to W of at least 1.10