LCA: News & Discussions - October 2016

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Re: LCA: News & Discussions - October 2016

Postby Vivek K » 18 Nov 2016 08:59

I can't find the pic of LCA Navy on BRF's FB page. Can someone post it here please?

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Re: LCA: News & Discussions - October 2016

Postby ks_sachin » 18 Nov 2016 10:22

its flown away mate...

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Re: LCA: News & Discussions - October 2016

Postby vina » 18 Nov 2016 10:43

Indranil wrote:Vina, they can attain 9G at 26 degrees (and even lower). They would enter the turn faster. The 8G limit is not due to AoA. Thanks for the info on the Mirage though. Learnt something new from that article.

Banked Turn
Load Factor
Does load factor depend on speed ?
Does radius of turn depend on speed (given a particular bank angle)?

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Re: LCA: News & Discussions - October 2016

Postby Indranil » 18 Nov 2016 12:18

I know what you are talking about. And let us just say that I know what I am talking about. Mk2 will be 9G capable. Will it be pulling more AoA with the same same wing, longer fuselage and almost same fin. You are knowledgeable. I will leave you with that.

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Re: LCA: News & Discussions - October 2016

Postby JayS » 18 Nov 2016 16:11

vina wrote:
Indranil wrote:Vina, they can attain 9G at 26 degrees (and even lower). They would enter the turn faster. The 8G limit is not due to AoA. Thanks for the info on the Mirage though. Learnt something new from that article.

Banked Turn
Load Factor
Does load factor depend on speed ?
Does radius of turn depend on speed (given a particular bank angle)?


Vina ji, relationship between load factor and bank angle is geometric in nature, and thus fixed for all aircrafts. But the lift produced in function of wing shape, eliminating other variables such as speed, altitude. Say you have two aicrafts of identical weights pulling 9G, the lift will have to be same for both of them = 9 x weight. But lets say for one wing the Lift vs AoA curve is steeper than the other - meaning Cl for one wing at same AoA is higher than the other. Obviously that wing will need to pull less AoA than the other. There is no direct relation in 9G and AoA, the way it is in bank angle and in 9G. That's what I wanted to point out.

Even if you do some back of the envelop number crunching, you will see than LCA has higher wing area for lower weight and thus lower wing loading. And thus its reasonable to expect it to be able to pull higher G at same AoA vis-à-vis M2K, or be able to pull same G at lower AoA as compared to M2K, unless of coarse, its Cl curve is significantly less steeper than M2K, which I don't think it is.

IR is correct in Saying that 8G limit is not due to AoA. Its a structural limit. In fact G-limit would not arise due to AoA at all. Whatever may be the stall angle, if the aircraft can go to high enough speed it could pull 9G or whatever G needed. If you look at V-n diagram carefully, you will realise that.

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Re: LCA: News & Discussions - October 2016

Postby vina » 18 Nov 2016 19:05

JayS wrote: relationship between load factor and bank angle is geometric in nature, and thus fixed for all aircrafts.

If I understood you correctly, in Inglees, what it means is that a Puss Moth at a bank angle of X deg and holding constant altitude will be pulling the same amount of Gs as Raptor with same bank angle , irrespective of the speed they are doing ? For eg.. the Puss Moth might be doing 150 kmph, while the Raptor might be doing 1500 kmph at say a bank angle of 30deg, and both will be pulling same g?

But the lift produced in function of wing shape, eliminating other variables such as speed, altitude. Say you have two aicrafts of identical weights pulling 9G, the lift will have to be same for both of them = 9 x weight. But lets say for one wing the Lift vs AoA curve is steeper than the other - meaning Cl for one wing at same AoA is higher than the other. Obviously that wing will need to pull less AoA than the other. There is no direct relation in 9G and AoA, the way it is in bank angle and in 9G. That's what I wanted to point out.

Ah, if you are conisdering a high aspect ratio "traditional wing" where the Cl Max will be around 15 to 18 deg and starts dropping off after that, vs a low aspect ratio, highly swept , thin wing like a Delta , I agree, that the AoA required in the first will be less.

Even if you do some back of the envelop number crunching, you will see than LCA has higher wing area for lower weight and thus lower wing loading. And thus its reasonable to expect it to be able to pull higher G at same AoA vis-à-vis M2K, or be able to pull same G at lower AoA as compared to M2K, unless of coarse, its Cl curve is significantly less steeper than M2K, which I don't think it is.

But the M2K and LCA are similar and can be idealised to a thin sheet of paper. The differnces between them will be small. If the M2K needs 29 deg, the LCA cant do the same at 24 or 26! It will be within a 5% difference in most cases. My best guess is, it would range 29deg, +/- 1 deg at best!

IR is correct in Saying that 8G limit is not due to AoA. Its a structural limit. In fact G-limit would not arise due to AoA at all. Whatever may be the stall angle, if the aircraft can go to high enough speed it could pull 9G or whatever G needed. If you look at V-n diagram carefully, you will realise that.

Ok. It depends on what they call as certified to 9G and what was the design point for that particular number ? Do they mean 9G with full tanks and a2a config ? In that case, even if the LCA is overweight by 1 ton (from the original number), it can still pull the full 9G AFTER 1 ton of fuel is used up ! Even the SU 30 doesnt pull full 9G or whatever until the "internal auxiliary tank" gets emptied out. ie, it cant pull full 9G with all the tanks topped up! It is certified at I think 80% or so internal fuel. In the absence of knowing EXACTLY what they are saying, it is difficult to say. Sure, they might set the FCS to limit it to 8G in full fuel and empty fuel , but theoretically, the FCS can allow it to pull more Gs as the plane lightens up (even if it was overweight).

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Re: LCA: News & Discussions - October 2016

Postby ashishvikas » 18 Nov 2016 21:19

Press Information Bureau
Government of India
Ministry of Defence
18-November-2016 18:55 IST
Export of LCA Tejas

The government proposes to export the Light Combat Aircraft (LCA) Tejas to other countries. In this connection preliminary discussions have been held with a few friendly countries.

Presently, HAL has established facilities for manufacturing and delivery of 8 LCA per annum.

There is a plan to ramp up the production rate from 8 to 16 Aircraft per annum progressively by 2019-20.

This information was given by Defence Minister Shri Manohar Parrikar in a written reply to Shri MI Shanavas in Lok Sabha today.

DM/NAMPI/RAJ


http://pib.nic.in/newsite/PrintRelease. ... lid=153870

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Re: LCA: News & Discussions - October 2016

Postby JayS » 19 Nov 2016 01:11

vina wrote:
JayS wrote: relationship between load factor and bank angle is geometric in nature, and thus fixed for all aircrafts.

If I understood you correctly, in Inglees, what it means is that a Puss Moth at a bank angle of X deg and holding constant altitude will be pulling the same amount of Gs as Raptor with same bank angle , irrespective of the speed they are doing ? For eg.. the Puss Moth might be doing 150 kmph, while the Raptor might be doing 1500 kmph at say a bank angle of 30deg, and both will be pulling same g?


in short, Yes. For horizontal turn with no loss of altitude, the relationship between G-factor and angle of turn is given by:

n = 1 / cos(phi)

phi being the bank angle. This is pure geometry. This link has some good explanation:

http://www.aerospaceweb.org/question/performance/q0146.shtml

You'll also note that the variable of speed does not show up in this equation, only the bank angle. It is for this reason that the load factor is independent of velocity. Any aircraft in a level turn and pulling a given number of g's must maintain a constant bank angle independent of its speed or its weight.


At given G loading, the velocity decides radius of turn. Higher the velocity, higher is the radius. So will in your example both aircrafts would be doing same G-turn at same banking angle, but the puss moth would have far smaller turning radius as compared to the Raptor. Indeed some WW era planes could turn on a dime, but they were no way near 9G load. Because they were too slow. Despite their incredible turning ability they would be shot down like mosquitoes in today's era, due to their slow speed.

Note also the equations for R (turn radius) and omega (turn rate) from the above link. For given G-load turn, R is proportional to square of velocity while omega is inversely proportional to velocity.


vina wrote:
But the lift produced in function of wing shape, eliminating other variables such as speed, altitude. Say you have two aicrafts of identical weights pulling 9G, the lift will have to be same for both of them = 9 x weight. But lets say for one wing the Lift vs AoA curve is steeper than the other - meaning Cl for one wing at same AoA is higher than the other. Obviously that wing will need to pull less AoA than the other. There is no direct relation in 9G and AoA, the way it is in bank angle and in 9G. That's what I wanted to point out.

Ah, if you are conisdering a high aspect ratio "traditional wing" where the Cl Max will be around 15 to 18 deg and starts dropping off after that, vs a low aspect ratio, highly swept , thin wing like a Delta , I agree, that the AoA required in the first will be less.


Even if we consider two delta's, any two delta wings will not have exact same Cl vs AoA curve, in general. All I was saying it, every aircraft will produce different lift at same AoA.

vina wrote:
Even if you do some back of the envelop number crunching, you will see than LCA has higher wing area for lower weight and thus lower wing loading. And thus its reasonable to expect it to be able to pull higher G at same AoA vis-à-vis M2K, or be able to pull same G at lower AoA as compared to M2K, unless of coarse, its Cl curve is significantly less steeper than M2K, which I don't think it is.

But the M2K and LCA are similar and can be idealised to a thin sheet of paper. The differnces between them will be small. If the M2K needs 29 deg, the LCA cant do the same at 24 or 26! It will be within a 5% difference in most cases. My best guess is, it would range 29deg, +/- 1 deg at best!


The two aircrafts have enough differences to have noticeable difference in lift curve. IMO we can't say they will be very near to each other.

vina wrote:
IR is correct in Saying that 8G limit is not due to AoA. Its a structural limit. In fact G-limit would not arise due to AoA at all. Whatever may be the stall angle, if the aircraft can go to high enough speed it could pull 9G or whatever G needed. If you look at V-n diagram carefully, you will realise that.

Ok. It depends on what they call as certified to 9G and what was the design point for that particular number ? Do they mean 9G with full tanks and a2a config ? In that case, even if the LCA is overweight by 1 ton (from the original number), it can still pull the full 9G AFTER 1 ton of fuel is used up ! Even the SU 30 doesnt pull full 9G or whatever until the "internal auxiliary tank" gets emptied out. ie, it cant pull full 9G with all the tanks topped up! It is certified at I think 80% or so internal fuel. In the absence of knowing EXACTLY what they are saying, it is difficult to say. Sure, they might set the FCS to limit it to 8G in full fuel and empty fuel , but theoretically, the FCS can allow it to pull more Gs as the plane lightens up (even if it was overweight).


Just take design point for simplicity - A2A combat load with say 50% internal fuel and all fighters should be able to pull full rated G loaded at this config.

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Re: LCA: News & Discussions - October 2016

Postby vina » 19 Nov 2016 06:21

JayS wrote:At given G loading, the velocity decides radius of turn. Higher the velocity, higher is the radius. So will in your example both aircrafts would be doing same G-turn at same banking angle, but the puss moth would have far smaller turning radius as compared to the Raptor. Indeed some WW era planes could turn on a dime, but they were no way near 9G load. Because they were too slow.

As Mr Spock says in StarTrek, the black and red "don't compute"

Even if we consider two delta's, any two delta wings will not have exact same Cl vs AoA curve, in general. All I was saying it, every aircraft will produce different lift at same AoA.

Ok. Consider two aircrafts with the SAME wing, like Tejas Mk1 and Tejas MKII. Now if Tejas MK1 can pull only 8G in a turn, while Tejas MK2 with the same wing , pulls 9G, Tejas MK2 has to have a higher angle of attack than Mk1 , because it pulls more Gs (and the CL curve for deltas seem to be rising with alpha, well past 30 deg), and of course like everyother plane pulling 9G , Mk2 has to bank exactly to 83.6 deg or whatever it is , doesn't it ? Now if Mk1 is certified for 8G and 26 deg AoA while pulling it, Mk2 for 9G has to be more than 26 deg, which agrees with the numbers I pulled for M2K and seems to be of the order of 29 deg!

Just take design point for simplicity - A2A combat load with say 50% internal fuel and all fighters should be able to pull full rated G loaded at this config.

If that is the case, I would take the g ratings of most of the aircraft in the world with HUGE dollops of salt, and that includes the Gripens. Most manufactures would set their own "definition" of condition under which the 9G. In fact, I would not consider the fuel in the cft of the F16 Blk 52 and above as not "internal " fuel at all, but a Su-30 like "fudge".

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Re: LCA: News & Discussions - October 2016

Postby Indranil » 19 Nov 2016 06:59

Given a wing, AoA is not the only way to increase lift.

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Re: LCA: News & Discussions - October 2016

Postby shiv » 19 Nov 2016 07:11

This "load factor" thing is weird. I Googled for it a couple of weeks ago and had made the following post. I am putting my own post here for my own benefit because what I wrote was what I understood:
It seems to me (courtesy Googling) that load factor is the G force/lift that the plane can provide in a banking turn irrespective of size and weight of the plane.

A 9G load factor plane can bank at about 85 degrees while turning because 9G is what is needed to keep the plane flying at 85 degree bank (2G is at 60 degrees bank)

But there are 3 interconnected issues here

    Stall speed increases with weight
    Stall speed increases with increasing angle of bank
    Increased speed always means increased radius of turn


What this means is that a minimum radius turn for a lighter aircraft will be tighter than that of a heavier one because the stall speed for the heavier one is higher independent of bank angle/load factor.

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Re: LCA: News & Discussions - October 2016

Postby vina » 19 Nov 2016 12:17

Indranil wrote:Given a wing, AoA is not the only way to increase lift.


Ok. You fly faster you get more lift. However are talking same wings pulling more Gs here. 8 G vs 9G.

Ah. But JayS and Shiv and others answered that g load is independent of speed ? So just by flying faster, it doesn't seem that you can generate more g out of ANY wing .

Again as Mr Spock said in StarTrek, it "Doesn't Compute" . How will you generate more G with the same wing without more alpha (assuming Cl continues increasing with alpha as seems to be case with low aspect ration swept wings like the Delta at these alpha levels) ?

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Re: LCA: News & Discussions - October 2016

Postby GShankar » 19 Nov 2016 19:23

@JayS - stress/fatigue testing was only done on fuselage by this certain team while integration and test firing of the gun.

IAF is onto doing trial runs with the gun since the plane is handed over to them.

Heard IFR is from SP21 onwards.

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Re: LCA: News & Discussions - October 2016

Postby JayS » 19 Nov 2016 20:03

GShankar wrote:@JayS - stress/fatigue testing was only done on fuselage by this certain team while integration and test firing of the gun.

IAF is onto doing trial runs with the gun since the plane is handed over to them.

Heard IFR is from SP21 onwards.


Aha...Thanks for that info.

Yes IFR is part of FOC, so it won't be on first 20 IOC jets.

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Re: LCA: News & Discussions - October 2016

Postby Bhaskar_T » 19 Nov 2016 20:12

Apologies, I have not been regular in following this thread, may be I missed it. Are you saying that gun trials which were going on a certain LSP have been concluded (tested, verified, okayed by HAL/ADA pilots)? And, since only SP's are handed over to IAF, hence either of SP1/SP2/SP3 has been fitted over with the gun and given to IAF asking customer feedback on gun?

GShankar wrote:@JayS - stress/fatigue testing was only done on fuselage by this certain team while integration and test firing of the gun.

IAF is onto doing trial runs with the gun since the plane is handed over to them.

Heard IFR is from SP21 onwards.

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Re: LCA: News & Discussions - October 2016

Postby Bhaskar_T » 19 Nov 2016 20:18

Same news, as posted by Tejas_warrior, of Tejas export informed by Parrikar ji in Parliament, but this one is on sputnik. So, if India wants to export Tejas to Sri Lanka, Nigeria, Bangladesh, Vietnam, which of these countries are unfriendly to USA, Israel and Russia?

New Delhi (Sputnik) — India is trying to make the low cost and simple design of Tejas its unique selling proposition to cost-conscious countries in Asia.

“Indian government proposes to export the LCA Tejas to other countries and in this connection preliminary discussions have been held with a few friendly countries,” says Manohar Parrikar, Indian Defense Minister. The Indian Ministry of Defense claims to have received a positive response from a few Asian nations. They have found it attractive due to its low cost and simple design. But it is not known if re-export permissions are required from overseas suppliers of components. Its engines are American, radar, helmet display and laser pod of Israeli make and Russia has supplied the canons and missiles.

India’s Lethal 1370 MPH 4.5 Generation Tejas Fighter Jet Completes Maiden Flight India had symbolically formed the first squadron of Tejas in July this year with two initial operational configuration (IOC) aircraft. The remaining 18 jets in the same configuration will be inducted over the next two years. This will be followed by the induction of 20 Tejas in the Final Operation Configuration (FOC). The indigenous content is 59.7 per cent by value and attempts are on to localize the production of some more imported components. The state-owned Hindustan Aeronautics Limited can currently assemble eight Tejas per annum. It has plans to double the output to 16 Aircraft per annum.

Read more: https://sputniknews.com/military/201611 ... ia-export/

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Re: LCA: News & Discussions - October 2016

Postby JayS » 19 Nov 2016 22:41

Bhaskar_T wrote:Same news, as posted by Tejas_warrior, of Tejas export informed by Parrikar ji in Parliament, but this one is on sputnik. So, if India wants to export Tejas to Sri Lanka, Nigeria, Bangladesh, Vietnam, which of these countries are unfriendly to USA, Israel and Russia?



India could do what Sweden did with Gripen exports. Give the customer guarantee for availability of all the spares by pooling spares of entire Tejas fleet, in India and outside, and maintaining imported LRU/spares in a depot with IAF or HAL in sufficiant quantity. GoI will have to put its weight behind and IAF will have to co-operate if we want to export. HAL cannot do it.


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Re: LCA: News & Discussions - October 2016

Postby ashishvikas » 20 Nov 2016 09:33



Did he mean to say Range is 450Km with 3.5 ton load ?

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Re: LCA: News & Discussions - October 2016

Postby Austin » 20 Nov 2016 09:44



So he says Tejas is as capable as any aircraft and he took the initiative to get Tejas going, Yet he wants to order 200 Gripen or F-16, what a hypocrite he is

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Re: LCA: News & Discussions - October 2016

Postby khan » 20 Nov 2016 10:50

Austin wrote:


So he says Tejas is as capable as any aircraft and he took the initiative to get Tejas going, Yet he wants to order 200 Gripen or F-16, what a hypocrite he is


Isn't there room in IAF for 250-350 light fighters - evenly split between F-16 and LCA?

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Re: LCA: News & Discussions - October 2016

Postby Manish_Sharma » 20 Nov 2016 11:14



Panaji: The indigenously manufactured light combat aircraft 'Tejas', which was inducted into the Indian Air Force earlier this year, is as good as the French-made Rafale fighter jet and comparable with other top LCAs across the world, Defence Minister Manohar Parrikar said on Saturday.

"This is a plane which is completely indigenously manufactured and can compete with any other fighter plane in the world. It is as capable as the Rafale. Only this is a light combat aircraft (LCA)," Mr Parrikar said.

"Only a 3.5 ton missile can be carried on it, Rafale on the other hand can carry a nine-ton (missile). This plane can fly at the rate of 450 km, Rafale can run 900 km because it has twin engines," he added.

The Defence Minister also said that the Tejas, which was stalled for 33 years, was expedited because of his explicit directions to those in-charge of the project.

"I told them that all shortcomings should be fulfilled and the plane should be ready in a year," Mr Parrikar said, adding that some days ago an order had been placed for 83 more planes.


Image
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Re: LCA: News & Discussions - October 2016

Postby Austin » 20 Nov 2016 11:25

khan wrote:
Austin wrote:
So he says Tejas is as capable as any aircraft and he took the initiative to get Tejas going, Yet he wants to order 200 Gripen or F-16, what a hypocrite he is


Isn't there room in IAF for 250-350 light fighters - evenly split between F-16 and LCA?


Why should there be a split when you have Tejas ready , Why not make more if it and in DM own word they are as capable as any thing out there.

Even for a more simplistic argument , Why on earth would one even think of complicating logistics operating two types or pay LM or SAAB when we have Tejas ready.

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Re: LCA: News & Discussions - October 2016

Postby JayS » 20 Nov 2016 12:23

vina wrote:
Even if we consider two delta's, any two delta wings will not have exact same Cl vs AoA curve, in general. All I was saying it, every aircraft will produce different lift at same AoA.

Ok. Consider two aircrafts with the SAME wing, like Tejas Mk1 and Tejas MKII. Now if Tejas MK1 can pull only 8G in a turn, while Tejas MK2 with the same wing , pulls 9G, Tejas MK2 has to have a higher angle of attack than Mk1 , because it pulls more Gs (and the CL curve for deltas seem to be rising with alpha, well past 30 deg), and of course like everyother plane pulling 9G , Mk2 has to bank exactly to 83.6 deg or whatever it is , doesn't it ? Now if Mk1 is certified for 8G and 26 deg AoA while pulling it, Mk2 for 9G has to be more than 26 deg, which agrees with the numbers I pulled for M2K and seems to be of the order of 29 deg!


You are again assuming that MK1 needs to hit 24 or 26deg AoA for 8G. Which is not necessarily true. You have to understand this, G limit is a structural limit not an aerodynamic limit. Lets say LCA MK1 has corner speed of 350knots and it pulls 8G at limit AoA of 26deg at 350knots. This doesn't mean it can't pull 8G at any other AoA. It can easily pull 8G even at 20deg AoA, its just that now it will have to go to higher speed for 8G turn, say 400knots. In fact, it could pull 8G turn at even 10AoA if it would be flying fast enough - may be supersonic. See the V-n diagram below. Point A is the corner point and this is what we are talking about.

Image

I am being lazy in drawing a V-N diagram to explain my point. So please bear with me and in following image, ignore the ft numbers on the stall line. For the same altitude, in approximate terms, the blue line represents say 24 deg AoA limit, Orange line = 26deg AoA and Red line = 28deg AoA. The G-limit line which is the top horizontal line remains horizontal all the way. But due to shifting stall line leftwards with increasing AoA limit, shifts corner point towards lower speed. If you also try to shift G-limit line above or below, you could imagine what will happen to Corner point for same AoA - changing G-limit and changing AoA - changing G-limit.
Image

The importance of higher AoA limit is it just reduces the minimum speed at which the plane could pull highest G. Lowest speeds means lowest radius of turn and highest turning rate. Now apply this to MK1 vs MK2. Keeping same AoA limit, MK2 will have slightly higher corner speed for 9G than the corner speed of MK1 at 8G. The difference would be of the order of 20knots or so, IMO. But MK2 will have to pull slightly higher AoA if the corner speed has to be the same for 8G of MK1 and 9G for MK2. Now we know Mk1 pulls 8G with 24deg AoA limit at say x knots speed. By increasing AoA to 26deg will ensure that MK2 will pull 9G with 26deg AoA at more or less the same corner speed of x knots.

One more thing to be noted is, corner point represents fastest turn, but it could be held by the aircraft only for few seconds. Thus the name ITR. It finally has to settle to lower turn rate to sustain the turn - STR. Hence STR is always lower than ITR. The available engine thrust plays a role here.

vina wrote:
Just take design point for simplicity - A2A combat load with say 50% internal fuel and all fighters should be able to pull full rated G loaded at this config.

If that is the case, I would take the g ratings of most of the aircraft in the world with HUGE dollops of salt, and that includes the Gripens. Most manufactures would set their own "definition" of condition under which the 9G. In fact, I would not consider the fuel in the cft of the F16 Blk 52 and above as not "internal " fuel at all, but a Su-30 like "fudge".


And you should. 9G envelop is limited by many factors. For example, on the Single Engine Jet thread we had this discussion of F16 blk 52 and its capability of pulling 9G with CFT. I pointed out that design point for F16 blk 52 is that it can pull 9G until weight is below 28500 lbs or so. Indeed every aircraft AQR would tell exact conditions for 9G capability. For fighters, its mostly A2A load with full or partial internal fuel. Some fighters its 100% internal fuel like for F16. For one jet its 80% internal fuel (can't remember which one). Some has it for 50% internal fuel only. Even at this weight configuration, a fighter cannot pull 9G in its entire flight envelop due to other limits like altitude, Mach number, available excess thrust etc. Thats why its important to always check at what conditions, the performance is specified. Without the conditions specified the performance numbers are next to useless.
Last edited by JayS on 20 Nov 2016 12:38, edited 3 times in total.

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Re: LCA: News & Discussions - October 2016

Postby Vivek K » 20 Nov 2016 12:24

Making 250 - 300 LCA would develop an industry and a future for domestic weapon systems. If the Tejas is as capable as the Rafale, then the IAF is just as foolish as the GOI.

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Re: LCA: News & Discussions - October 2016

Postby JayS » 20 Nov 2016 12:46

Vivek K wrote:Making 250 - 300 LCA would develop an industry and a future for domestic weapon systems. If the Tejas is as capable as the Rafale, then the IAF is just as foolish as the GOI.


I am sure RM must have said it in certain context or performance parameters which only he knows. But generalizing it would be a mistake. That's expected from MSM. But at least we at BRF should not do that. There are certain things that Rafale could do and LCA could not. Even the staunchest LCA supporters would have to accept it.

This is another question that, was it possible to get those things done with say Su-30MKI and avoid purchase of mere 36 Rafale. But lets not discuss that here.

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Re: LCA: News & Discussions - October 2016

Postby Neshant » 20 Nov 2016 14:01




At the end of the day, these explanations are worthless if the LCA is not mass produced.
China has mass produced its J-10, copied the Sukhoi-27 (J-11) and producing its J-12.
We are still stuck writing articles desperately trying to fend off critics.

So far the only thing received are meaningless "Acceptance of Necessity" for 83 LCA planes.
These are not orders.
Until there are orders, there will be no expansion of the production lines from 8 to 16 planes.

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Re: LCA: News & Discussions - October 2016

Postby ashishvikas » 20 Nov 2016 16:23

http://english.mathrubhumi.com/mobile/n ... -1.1519345

By: By Our Defence Correspondent
20 Nov 2016, 03:27 pm
Bengaluru:
On a specific query on the Final Operational Clearance for Tejas, Aeronautical Development Agency head Cmde C D Balaji (Retd) said the process will be completed next year.
“We hope that Tejas would get the FOC by mid of 2017.
The BVR Derby missile will be fired again next month.
The gun integration work is completed.
The air-to-air refuel ling probe too will be tested next year,” Balaji said.



DRDO DG (Aero) C P Ramanarayanan said LCA with Kaveri engine might fly in 2018. :shock:

He said DRDO is already in consultation with Snecma. Already Rs 2,105 crore has been spent on the project. Another Rs 600 crore is likely to be needed for the testing phase.

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Re: LCA: News & Discussions - October 2016

Postby Pratyush » 20 Nov 2016 17:19

Whiskey tango foxtrot for Kaveri please make it work. :(( :((

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Re: LCA: News & Discussions - October 2016

Postby Bhaskar_T » 20 Nov 2016 17:45

No idea how old is this pdf on ADA website but it appears as a running ticker on main page. ADA is asking vendors to show interest in making about 112 LRU imported components and ADA is offering technical help so that vendors can achieve the deliverable's.

This would be very interesting to see how many vendors show interest in the developments of these LRU's. Hope recent 83 orders in addition to original 40 orders encourage vendors to step up, make business and deliver the products for Desh. Wonder, which of these technologies/products already exist in India and these were imported to date only because scale of orders weren't available. Categorized in few areas, Avionics, Environmental Control, Electrical, Flight Control, Hydraulic, Landing Gear, Propulsion & Fuel Mainly. I will split the 112 components into few posts to avoid one long post and also to help anyone quoting on these components as per their category. I tried copying and pasting into excel so that it could be put here as one image but copying from ADA's pdf is not getting pasted into excel (Text To Columns is not useful here).

Gurus - Any comments?

PS - JayS - Thanks for your replies to my previous posts.

INDIGENOUS DEVELOPMENT OF LINE REPLACEABLE UNITS (LRU’s) - FOR LCA-TEJAS

https://www.ada.gov.in/adawebsitedev.html

ADA is the Nodal agency involved in the design and development of Tejas Aircraft along with HAL as a principal partner and in coordination with nearly 100 work centres spread across the country. The Tejas development program is in advanced stage, completed Initial Operation Clearance (IOC) requirements and marching towards final operation clearance (FOC). Tejas has completed over 2000 flights so far and continuing system performance and evaluation towards reaching Final Operational Clearance (FOC). There are 358 LRU's (Components) in the Tejas aircraft, out of which 53% of total LRU's are indigenously developed with in India. In view to reduce the remaining 47% of the import LRU's, ADA has initiated the Indigenous development programme for indigenization of the import LRU's. The List of Components (LRU's) which belong to different systems of Aircraft, ADA is looking to indigenous is given in the table below.

ADA is inviting the vendors/developers who are willing to take up the development of above components. ADA will provide all the information about components, Such as Technical Specifications, Test Requirements etc.

Sl. No. System Equipment / LRU
1 Avionics Enhanced – Video cum Digital Recorder (E-VDR)
2 Avionics E-VDR Remote Cassette Unit Holder (RCUH)
3 Avionics E-VDR Removable Mass Memory Device
4 Avionics Global Positioning System (GPS)- Antenna
5 Avionics Gyro Reference Unit [GRU]
6 Avionics HMDS (Head Mounted Display System) -
Guillotine Assembly
7 Avionics HMDS-Line of sight computer Unit
8 Avionics HMDS-Magnetic Transmitter Coil Unit [MTCU]
9 Avionics HMDS-Seat Position Sensor Assembly
10 Avionics HMDS-System Control Panel
11 Avionics Identification Friend or Foe (IFF) - Antenna
12 Avionics Marker Antenna
13 Avionics MMR (Multi Mode Radar) - Ethernet switch
14 Avionics Multi Function Display Unit [MFD]
15 Avionics Radio Altimeter (RAM)-Antenna
16 Avionics RWR (Radar Warning Receiver) - Antenna
17 Avionics RWR - Power Divider
18 Avionics RWR - Switch Filter Assembly (RF Units)
19 Avionics Tactical Navigation (TACAN) - Antenna
20 Avionics Very/ Ultra High Frequency (V/UHF) Blade Antenna
21 Avionics Very/ Ultra High Frequency (V/UHF) Radio ACR 500LA
22 Avionics VHF Omni Range – Instrument Landing System (VOR – ILS) Blade Antennas
23 Avionics VOR - ILS Diplexer



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Re: LCA: News & Discussions - October 2016

Postby Bhaskar_T » 20 Nov 2016 17:49

Adding 26 Environment Control systems to the previous 23 Avionics products list in my previous post.

INDIGENOUS DEVELOPMENT OF LINE REPLACEABLE UNITS (LRU’s) - FOR LCA-TEJAS

https://www.ada.gov.in/adawebsitedev.html

ADA is the Nodal agency involved in the design and development of Tejas Aircraft along with HAL as a principal partner and in coordination with nearly 100 work centres spread across the country. The Tejas development program is in advanced stage, completed Initial Operation Clearance (IOC) requirements and marching towards final operation clearance (FOC). Tejas has completed over 2000 flights so far and continuing system performance and evaluation towards reaching Final Operational Clearance (FOC). There are 358 LRU's (Components) in the Tejas aircraft, out of which 53% of total LRU's are indigenously developed with in India. In view to reduce the remaining 47% of the import LRU's, ADA has initiated the Indigenous development programme for indigenization of the import LRU's. The List of Components (LRU's) which belong to different systems of Aircraft, ADA is looking to indigenous is given in the table below.

ADA is inviting the vendors/developers who are willing to take up the development of above components. ADA will provide all the information about components, Such as Technical Specifications, Test Requirements etc.

Sl. No. System Equipment / LRU
24 Environmental Control Bypass Valve PHE (Primary Heat Exchanger)
25 Environmental Control Cabin Pressure Control Valve
26 Environmental Control Cabin Pressure Safety Valve
27 Environmental Control Cabin Shut-Off Valve
28 Environmental Control ECS-Shut-Off Valve
29 Environmental Control Ejector Shut Off Valve (ESOV)
30 Environmental Control Filter Cabin Pressure Control
31 Environmental Control Flow Control Valve - Avionics cooling
32 Environmental Control Inward Relief Valve
33 Environmental Control Pressure Reducer-Radar and Cabin Seal Pressurization
34 Environmental Control Pressure Sensor Avionics Inlet
35 Environmental Control Pressure Sensor P26 (Condenser)
36 Environmental Control Pressure Sensor- P79(Avionics Flow Control)
37 Environmental Control Pressure Sensor P24 - Bleed Air Inlet
38 Environmental Control Pressure Switch (Bleed Air Inlet)
39 Environmental Control Pressure Switch-High
40 Environmental Control Pressure Switch-Low
41 Environmental Control Pressure Transducer-Cabin
42 Environmental Control PRV-SOV
(Pressure Reduction Valve/Shut off Valve)
43 Environmental Control PRV-SOV- Control Unit
44 Environmental Control Seal Inflation / Deflation Valve
45 Environmental Control Temperature Control Valve
46 Environmental Control Temperature Sensor (High)
47 Environmental Control Temperature Sensor (Low)
48 Environmental Control Temperature Sensor-Pneumatic
49 Environmental Control Water Separator

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Re: LCA: News & Discussions - October 2016

Postby Bhaskar_T » 20 Nov 2016 17:54

Adding Electrical, Flight Control, Hydraulic Control systems to the previous Avionics, Environmental Control products list in my previous post.

INDIGENOUS DEVELOPMENT OF LINE REPLACEABLE UNITS (LRU’s) - FOR LCA-TEJAS

https://www.ada.gov.in/adawebsitedev.html

ADA is the Nodal agency involved in the design and development of Tejas Aircraft along with HAL as a principal partner and in coordination with nearly 100 work centres spread across the country. The Tejas development program is in advanced stage, completed Initial Operation Clearance (IOC) requirements and marching towards final operation clearance (FOC). Tejas has completed over 2000 flights so far and continuing system performance and evaluation towards reaching Final Operational Clearance (FOC). There are 358 LRU's (Components) in the Tejas aircraft, out of which 53% of total LRU's are indigenously developed with in India. In view to reduce the remaining 47% of the import LRU's, ADA has initiated the Indigenous development programme for indigenization of the import LRU's. The List of Components (LRU's) which belong to different systems of Aircraft, ADA is looking to indigenous is given in the table below.

ADA is inviting the vendors/developers who are willing to take up the development of above components. ADA will provide all the information about components, Such as Technical Specifications, Test Requirements etc.

Sl. No. System Equipment / LRU

50 Electrical 0.35 kVA HMDG (Hydraulic Motor Driven
Generatror) – LH (Left Hand)
51 Electrical 0.35 kVA HMDG – RH (Right Hand)
52 Electrical 0.35 kVA HMDG – VRU (Voltage Regulator Unit)
53 Electrical 30 / 40 kVA IDG (Integral Drive Generator)
54 Electrical 30 / 40 kVA IDG-GCU (Generator Control Unit)
55 Electrical 5 kVA HMDG
56 Electrical 5 kVA HMDG -GCU
57 Electrical Ground Power Receptacle (GPR)
58 Electrical Light - Anti Collision
59 Electrical Light Taxi/Landing
60 Electrical Light-Wander
61 Electrical Power Supply Unit - Anti Collision Light
62 Electrical Undercarriage display unit
63 Electrical Undercarriage Selector Lever

64 ESCAPE Ejection Seat


65 Flight Control Air Data Probe [NADP]

66 Flight Control Air Data Sensor - Left Side [LADP]
67 Flight Control Air Data Sensor - Right Side [RADP]
68 Flight Control AoA (Angle of Attach) Sensor [AoA / AoSS vanes]
69 Flight Control Pilot Control Grip
70 Flight Control Leading Edge Vane Controller (LEVCON) Servo Actuator Assembly
71 Flight Control Probe Total Temperature [TATP]
72 Flight Control Sensor Assembly, Accelerometer [ASA]
73 Flight Control Sensor Assembly Rate [RSA]


74 Health and Utility Management System (HUMS) HUMS-Data Acquisition unit

75 Hydraulic Control cable - Park Brake Control
76 Hydraulic Control cable - Under carriage Emergency
77 Hydraulic Emergency Undercarriage Selector Valve
78 Hydraulic Flow Synchronizer
79 Hydraulic Pressure Gauge
80 Hydraulic Pressure Switches
81 Hydraulic Pressure Switch – EMDP (Electric Motor Driven Pump)
82 Hydraulic Pressure Switch - P/B
83 Hydraulic Pressure Transducers
84 Hydraulic Progressive Pressure Control Valve
85 Hydraulic Slide & Swivel Joints


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Re: LCA: News & Discussions - October 2016

Postby Bhaskar_T » 20 Nov 2016 17:56

Adding Landing Gear, Propulsion & Fuel systems to the previous Electrical, Flight Control, Hydraulic Control systems, Avionics, Environmental Control products list in my previous post.

INDIGENOUS DEVELOPMENT OF LINE REPLACEABLE UNITS (LRU’s) - FOR LCA-TEJAS

https://www.ada.gov.in/adawebsitedev.html

ADA is the Nodal agency involved in the design and development of Tejas Aircraft along with HAL as a principal partner and in coordination with nearly 100 work centres spread across the country. The Tejas development program is in advanced stage, completed Initial Operation Clearance (IOC) requirements and marching towards final operation clearance (FOC). Tejas has completed over 2000 flights so far and continuing system performance and evaluation towards reaching Final Operational Clearance (FOC). There are 358 LRU's (Components) in the Tejas aircraft, out of which 53% of total LRU's are indigenously developed with in India. In view to reduce the remaining 47% of the import LRU's, ADA has initiated the Indigenous development programme for indigenization of the import LRU's. The List of Components (LRU's) which belong to different systems of Aircraft, ADA is looking to indigenous is given in the table below.

ADA is inviting the vendors/developers who are willing to take up the development of above components. ADA will provide all the information about components, Such as Technical Specifications, Test Requirements etc.

Sl. No. System Equipment / LRU
86 Landing Gear Antiskid Brake Manifold
87 Landing Gear Brake Feel Module Input Potentiometer
88 Landing Gear Free castor valve for Nose Wheel Steering
(Solenoid valve)
89 Landing Gear Nose Wheel Steering Input Potentiometer
90 Landing Gear Nose Wheel Steering Manifold
91 Landing Gear Nose Wheel Steering Position Sensor (Feedback potentiometer)


92 Propulsion and Fuel Air / No Fuel Float Valve
93 Propulsion and Fuel Differential Pressure Switch
94 Propulsion and Fuel Electric Re-fuelling Valve
95 Propulsion and Fuel Engine third mount pin
96 Propulsion and Fuel Float Valve
97 Propulsion and Fuel Fuel Drain Valve
98 Propulsion and Fuel Fuel Filler Cap
99 Propulsion and Fuel Fuel flow straighter
100 Propulsion and Fuel Fuel flow Transmitter
101 Propulsion and Fuel Fuel Shut Off Cock
102 Propulsion and Fuel Fuel/No Air Valve
103 Propulsion and Fuel Low Pressure Fuel Shut Off Cock dia 25 mm
104 Propulsion and Fuel Motorized Fuel Transfer Valve
105 Propulsion and Fuel Pressure Reducing Valves
106 Propulsion and Fuel Surge Relief Valve - F1 & F2 tanks
107 Propulsion and Fuel Surge Relief Valve - F1A tanks
108 Propulsion and Fuel Surge Relief Valve - Wing tanks
109 Propulsion and Fuel Throttle Grip
110 Propulsion and Fuel Throttle Quadrant Assembly
111 Propulsion and Fuel Transfer Cum Refueling Valve


112 Utility Services and Monitoring (USMS) Charge Amplifier (Pre Amplifier)

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Re: LCA: News & Discussions - October 2016

Postby Bhaskar_T » 20 Nov 2016 18:06

Since maiden flight of SP-3, i.e. 28th Sept 2016, there were never any firm articles/reports saying that SP-3 had been delivered to IAF, however several members here got some info that SP-3 had been delivered to IAF. I asked Tejas-LCA fb admin again and he/she reiterated that SP-3 is still with HAL/ADA. In 8 days from now, it will be 2 months from SP-3 maiden flight and not yet delivered to IAF. Anyone knows what is the issue preventing a handover?

Image

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Re: LCA: News & Discussions - October 2016

Postby Vivek K » 20 Nov 2016 22:56

Are there two Naval Prototypes in operation?

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Re: LCA: News & Discussions - October 2016

Postby Karan M » 20 Nov 2016 23:14

Austin wrote:


So he says Tejas is as capable as any aircraft and he took the initiative to get Tejas going, Yet he wants to order 200 Gripen or F-16, what a hypocrite he is


Come on, he is doing what the IAF wants and he has got the Tejas confirmed orders. Give him time.

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Re: LCA: News & Discussions - October 2016

Postby Indranil » 20 Nov 2016 23:16

Bhaskar_T wrote:Since maiden flight of SP-3, i.e. 28th Sept 2016, there were never any firm articles/reports saying that SP-3 had been delivered to IAF, however several members here got some info that SP-3 had been delivered to IAF. I asked Tejas-LCA fb admin again and he/she reiterated that SP-3 is still with HAL/ADA. In 8 days from now, it will be 2 months from SP-3 maiden flight and not yet delivered to IAF. Anyone knows what is the issue preventing a handover?

Image

IAF may have asked for some extra tests.

Jay, good post. I wish the E-M diagrams of LCA were public. But one can imagine, that the doghouses will be shifted slightly to the right, and the roofs will be slightly taller to cover 9G.

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Re: LCA: News & Discussions - October 2016

Postby Cain Marko » 20 Nov 2016 23:48

Karan M wrote:
Austin wrote:
So he says Tejas is as capable as any aircraft and he took the initiative to get Tejas going, Yet he wants to order 200 Gripen or F-16, what a hypocrite he is


Come on, he is doing what the IAF wants and he has got the Tejas confirmed orders. Give him time.


Yes, at least he is doing "something". Not enough by jingo standards for sure, but better than recent past. I feel more tejas orders for iaf are inevitable once production variant is finalized, and production is stabilized. Would not be surprised if another couple of sqds is ordered at time of foc. Altogether at least 250 imvho.

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Re: LCA: News & Discussions - October 2016

Postby Viv S » 21 Nov 2016 00:14

Tejas gun integration complete. Another Derby test planned for December.

On a specific query on the Final Operational Clearance for Tejas, Aeronautical Development Agency head Cmde C D Balaji (Retd) said the process will be completed next year.

We hope that Tejas would get the FOC by mid of 2017. The BVR Derby missile will be fired again next month. The gun integration work is completed. The air-to-air refuelling probe too will be tested next year,” Balaji said.

DRDO DG (Aero) C P Ramanarayanan said LCA with Kaveri engine might fly in 2018. He said DRDO is already in consultation with Snecma. Already Rs 2,105 crore has been spent on the project. Another Rs 600 crore is likely to be needed for the testing phase.

http://english.mathrubhumi.com/news/ind ... -1.1519345

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Re: LCA: News & Discussions - October 2016

Postby Marten » 21 Nov 2016 00:53

DRDO needs to stop making any claims related to Kaveri.

Without completing ground tests or procuring a test bed for completing other tests, it seems outrageous that they continue making claims or predictions or promises.


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