LCA Tejas: News and Discussions

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member_29172
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Re: LCA Tejas: News and Discussions

Post by member_29172 »

SaiK wrote:ddm is waking up, a millimeter per day
http://www.indiandefencereview.com/news ... -air-show/
avoid spamming ddm here please, let them rot in their own filth. The proving its worth thing was done way before baharain.
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Re: LCA Tejas: News and Discussions

Post by SaiK »

you can't avoid them. we can only graduate them.

now, the word spamming is hard on me.
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Re: LCA Tejas: News and Discussions

Post by JayS »

SaiK wrote:nilesh and indranil jis, if you play the video again on a 0.25 speed, you can observe the pull up was almost in two steps.. that is from hz to almost 80* up, and then a slight slow correction to 90*.,

so I would "think" the turn happened within about 2.8 secs.
The vid posted by Nitin Gokhale gives best view of the pull up after the TO. I checked the vid in details. Its easy to mark starting of the loop since we can see a/c attitude changing. The end of the loop can be marked by the change in the smoke trail - when the pilot stops pulling up i.e reduce AoA, the high vortices disappear and more sedated vortices remain - it looks like the smoke trail becomes smooth. With these two markers - the pilot starts pulling up at 1.150s and stops at 5.200. That gives 4sec (+-0.1sec) for the loop.

Now that I see the turn in details, the start of the pull up looks sluggish, the attitude of the a/c changes much slowly than other jets such as F-18/Mig29 can manage. May be this pull-up manoeuvre isn't a 8G turn. From the video I measured 22 deg turn in initial 1.2sec. See the image below which has 4 superimposed instances from 1.200s to 2.450sec.

https://drive.google.com/file/d/0B2Jcr1 ... sp=sharing

This is not to say that LCA does not have ITR=30deg/sec. But atleast I failed to see it in this pull up. I thought initially this must be the hardest turn that it can take. Maybe its not.
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Re: LCA Tejas: News and Discussions

Post by Karan M »

Nilesh, its not. They played it safe and also tried to please the crowd - use the entire runway to fly low etc.
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Re: LCA Tejas: News and Discussions

Post by Indranil »

Nilesh, you know it can't be 22. Check the vertical pull up from the square loop. I used the second days video and the same method as yours, i.e. checking the smoke for vortices.
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Re: LCA Tejas: News and Discussions

Post by Karan M »

Alka_P wrote:
SaiK wrote:ddm is waking up, a millimeter per day
http://www.indiandefencereview.com/news ... -air-show/
avoid spamming ddm here please, let them rot in their own filth. The proving its worth thing was done way before baharain.
Disagree...every positive report needs to be on this thread...there will be vested interests galore.. some folks will wake up and we need to show case them here...
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Re: LCA Tejas: News and Discussions

Post by SaiK »

Asked for the names of countries which have evinced interest, Raju told PTI, "Believe us when I say there are inquiries for LCA."

http://economictimes.indiatimes.com/new ... 757927.cms

It is estimated that 20 aircraft will be built by 2017- 2018 to make the first squadron of the plane.
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Re: LCA Tejas: News and Discussions

Post by Akshay Kapoor »

Nilesh,

Thank you for the excellent posts in the last few days. This is the kind of high quality knowledge accumulation we should see on BR rather than opinionated (but often uninformed and incorrect) stuff we often see.

Quick question - after Indranlis's latest post what is your most conservative estimate of STR and ITR of Tejas. Do you still stick to 16.5degs/sec and 26 degs/sec respectively ? Also your analysis was with 1.5 tons of fuel and no payload right ?
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Re: LCA Tejas: News and Discussions

Post by sudeepj »

LCA will be great for Taiwan and Vietnam. They dont really need long legs and low cost, high tech platforms that can deter any 4G/4.5G platform over own skies is a winner for them.
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Re: LCA Tejas: News and Discussions

Post by hanumadu »

India should donate a few Rudra, LCH and LCAs for Afghanistan. What better way to prove your credentials than in a war?
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Re: LCA Tejas: News and Discussions

Post by Indranil »

They don't need a multirole aircraft. They should be given armed HTT-40s.
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Re: LCA Tejas: News and Discussions

Post by member_23370 »

They need Mi-35's since they operate a few and rudras will do fine. As for fighters they can get second hand mig-29's from Russia, nit sure LCA can be exported without US, Israeli and french yes.
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Re: LCA Tejas: News and Discussions

Post by sudeepj »

indranilroy wrote:They don't need a multirole aircraft. They should be given armed HTT-40s.
They are already buying the super tucanos. Ideally, the US should outsource its Afghanistan strategy to India. India supplies the weapons, the training and the trade necessary to support the Afghanistan govt. while the US writes aid checks. Divisions worth US soldiers in Afghanistan doesn't achieve much except giving the Pakis a pain point.
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Re: LCA Tejas: News and Discussions

Post by Kartik »



2nd day's performance.
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Re: LCA Tejas: News and Discussions

Post by SaiK »

IAF have a squadron of LCA Mk1as at Farkhor AB., with couple of MKIs as mini-awacs. nice place to test out our missions.
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Re: LCA Tejas: News and Discussions

Post by member_26622 »

So when is the big order coming? Which option feels good for anyone with some dose of commonsense :?:

Option 1 - 272 MKI + 100 LCA + 30 Shiny RAFALE +100 bhelpuri mix ~ 400 versus 2000 Chinese Fighter/Attack aircraft >> Run to US and start begging for help at end of week 1 of start of war

or

Option 2 - 272 MKI + 500 LCA + 100 bhelpuri mix ~ 900 versus 2000 Chinese Fighter/Attack aircraft >> No war as dumb Chinese generals can at least count :wink:

here are the test results :arrow: IAF selects Option 1, Rest of the World selects Option 2 :-?

Isn't this worth a good laugh.

Another news which we all know was long due - http://indiatoday.intoday.in/story/a-fi ... 81828.html
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Re: LCA Tejas: News and Discussions

Post by Cosmo_R »

IIRC, there is/was a penalty clause in the original 'tactically brilliant' MMRCA process designed by St. Anthony. It in effect said "you make us go through all these hoops, you'd better be serious and commit to buy the selected L1 bidder's product". If you cancel the buy after the the L1 has been selected, you owe much moolah (penalty) to them because you have caused every bidder who bought the materials and who spent gazillions on all the tests (hi/hi/lo/lo/nachna gana) to incur costs that they had no actual chance of recouping through a win.

IIUC, what Modi & co have done is to negotiate this penalty down to 36 off the shelf Rafales vs. 126 that we have no money for given OROP/Rural schemes/Mountain Strike corps etc.

Problem now is IAF wants two bases to handle Rafales vs 1 quoted, Astra integration (object codes/APIs) HMS etc etc... And the cost keeps creeping back up. The Rafale unit cost is going to be huge because of the smaller order. The offset raises the unit cost further because it's really another cost that Dassault has to factor in.

It will drag on as presently structured. Better to renegotiate the penalty and fudge it into the Areva nukes and invest heavily in LCA/AMCA and if you really need a gap filler, LEASE (FMS) the F/A-18 (it has the GE 414s) which will keep logistics costs low and get GE to give us a volume break (LCA/AMCA/F/A-18).

JMT
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Re: LCA Tejas: News and Discussions

Post by ramana »

Yes Cosmo_R the poison pill was UPA way of ensuring they get paid no matter.

Why cant the IAF take the planes as is and later worry about Astra/vastra?
Did they need all that when they did the evaluations?
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Re: LCA Tejas: News and Discussions

Post by Sid »

Another upgrade to include homegrown weapons will be 1-2 billion worth of contract and will require billion yrs to signoff.

Hence based on their bitter experience IAF will club whatever they can in one contract.

To think about its a good strategic decision, where firms like MBDA have everything to loose.
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Re: LCA Tejas: News and Discussions

Post by member_26622 »

I seriously am not bought on this poison pill logic.

Even with all expenses rolled up it will hardly be 100 million or 200 million at the most. Pay it off and get this tamasha over with please.

Since when did it make sense to do the same mistake 29 times over instead of one time? Pay it off once and get over with this lunacy!

Heck make a cardboard mockup of one Rafale jet and give it to IAF; infact make 29 cardboard copies as they will be as useful in an actual war as 29 real Rafale jets :rotfl:
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Re: LCA Tejas: News and Discussions

Post by Singha »

every significant aerospace power out there, as per its needs has a volume production of a basic type to fill the bulk of roles.
for US it was f-16. for china it is J-10.

the basic type must be 3:1 in numbers vs others to control costs.

36 rafale in 2 special bases is a soln to SL or BD going rogue, cheen will be :?:

its obviously a ploy to get +36 or +72(!) later once the foot is inside the door...and the GOI must not fall for this import lobby plan.
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Re: LCA Tejas: News and Discussions

Post by MN Kumar »

SaiK wrote:ddm is waking up, a millimeter per day
http://www.indiandefencereview.com/news ... -air-show/
IDR is not ddm. The msm still hasn't picked up the Tejas story.
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Re: LCA Tejas: News and Discussions

Post by JayS »

Karan M wrote:Nilesh, its not. They played it safe and also tried to please the crowd - use the entire runway to fly low etc.
May be you are right. May be the extended low flypass was needed in order to gain speed (300+knots) for 8G pull. May be just that particular pull up in the vid posted by Nitin Gokhale it was sluggish since it was practice session and they might be just warming up. Can't be sure.
indranilroy wrote:Nilesh, you know it can't be 22. Check the vertical pull up from the square loop. I used the second days video and the same method as yours, i.e. checking the smoke for vortices.
From the video snapshot it was 22, at max there could be 5deg error, still not nearly as much as expected. But as I said, may be its only for that practice run. In the second day vid, the same manoeuvre seems more aggressive. Also the corner pull up in the square loop when it goes from bottom horizontal to vertical is done in ~3.5s, the one when it goes vertical to the top horizontal leg of the loop that was even more quickly. But the corner turns at the top two corners are suppose to be faster than the two at the bottom. And ITR is quite the other thing than this. It looks as if, the LCA pilots did not pulled as hard as possible while entering the turn, perhaps because they did not want to bleed energy (JMT, FWIW). A fighter like F18/Mig29/F22 can afford to do that since they have super-duper TWR available. I am sure LCA can do better than that and we will see it in future some time. I can wait.

Akshay Kapoor wrote:Nilesh,

Thank you for the excellent posts in the last few days. This is the kind of high quality knowledge accumulation we should see on BR rather than opinionated (but often uninformed and incorrect) stuff we often see.

Quick question - after Indranlis's latest post what is your most conservative estimate of STR and ITR of Tejas. Do you still stick to 16.5degs/sec and 26 degs/sec respectively ? Also your analysis was with 1.5 tons of fuel and no payload right ?
The pleasure is all mine Saar. :mrgreen: I had been waiting for getting these data points.

The calculations I did, despite all the confusion in last few posts, is still valid since I took 4sec for 90deg 8G pull-up which is still valid. I still stand by those figures (since they are conservative) as long as the assumptions are valid. I took SL conditions, 50% internal fuel=1.2ton, clean config.

IMHO, considering the error band in measuring data from video and the error introduced due to idealised equations to real life manoeuvres, I think ITR=28deg/sec and STR=17deg can be easily accepted. Also I would expect these figures to go up slightly when LCA goes to 24deg AoA even in its current form, ITR=30deg/s and STR=18deg/s is easily possible. I can't wait to see MK2 though, that will be the real deal in terms of performance, truly world beater.
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Re: LCA Tejas: News and Discussions

Post by Indranil »

I don't think that the pull up (to vertical) right after take off and the bottom left corner of the box is at max ITR. Like you, I think that the focus at these corners was the exit speed rather than the entry speed. But to me, the left bottom corner from the second days display seemed to have taken between 3.5-4 seconds. The angle of the camera was good to judge the same. I felt even the bottom right corner was also in approximately negotiated in the same time.

At the top corners, the exit speed need not be a criteria. Plus, gravity aids in the turn. So, I expected these corners to be the sharpest. But I did not find a good angle to calculate the same.

Finally, I have also started having a feeling that we are yet to see the most aggressive display of the plane. That will come after a few years of fielding the plane, and some growth in confidence.
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Re: LCA Tejas: News and Discussions

Post by pragnya »

nileshr, excellent posts as usual. few queries though -

1. was the person who took video (picture) was exactly or approximately '90 degrees' to the point at which the pull up happens? if not (which is most likely) wont your estimation of the pull up angle be wrong. the fact that person is photographing from very far and considering the lens being not a high telephoto lens, is not the estimation going to be even more complicated?

2. again looking at the picture at the pull up, your slanting line does not correspond to the body (bottom) of the aircraft which seems more slanted than your line. for my amateur eye it looks 8-10 more degrees!!
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Re: LCA Tejas: News and Discussions

Post by JayS »

pragnya wrote: nileshr, excellent posts as usual. few queries though -

1. was the person who took video (picture) was exactly or approximately '90 degrees' to the point at which the pull up happens? if not (which is most likely) wont your estimation of the pull up angle be wrong. the fact that person is photographing from very far and considering the lens being not a high telephoto lens, is not the estimation going to be even more complicated?

2. again looking at the picture at the pull up, your slanting line does not correspond to the body (bottom) of the aircraft which seems more slanted than your line. for my amateur eye it looks 8-10 more degrees!!
The camera guy is very well positioned (you can judge yourself from the picture itself) for calculating initial pull up part (anyway, +-15 deg to exact perpendicular would not give much error). And plus smoke trail is present to give approximate path of the jet. The cameraman starts zooming in after 1.5sec into turn and there is no good marker to overlap the images. So i was restricted to 1.2sec into the turn. This image i made by using the building you see in background as a bearing point. Since its overlapped images and I did a real shoddy job at it in GIMP, the smoke trail is not visible in the composite image properly, but in original snapshots is more clear. I tried to draw line which would best represent tangent to the curved path at given instance. I am conservative indeed but I would say the error is no more than +5deg. Even with that the ITR is not as much as expected. In fact I don't even have to do this calculations to say that. If you see the video yourself by running it real slow, you will notice that the attitude change is much slower. Compare that to mig29 or f18 for ex. That's why I am saying LCA doesn't seem to be pulling at max ITR.
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Re: LCA Tejas: News and Discussions

Post by JayS »

indranilroy wrote:I don't think that the pull up (to vertical) right after take off and the bottom left corner of the box is at max ITR. Like you, I think that the focus at these corners was the exit speed rather than the entry speed. But to me, the left bottom corner from the second days display seemed to have taken between 3.5-4 seconds. The angle of the camera was good to judge the same. I felt even the bottom right corner was also in approximately negotiated in the same time.

At the top corners, the exit speed need not be a criteria. Plus, gravity aids in the turn. So, I expected these corners to be the sharpest. But I did not find a good angle to calculate the same.

Finally, I have also started having a feeling that we are yet to see the most aggressive display of the plane. That will come after a few years of fielding the plane, and some growth in confidence.
Agree totally. Also to 3.5s for that turn you mentioned is what I also calculated. The only way to calculate the turn time for left top turn is seeing vortices.
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Re: LCA Tejas: News and Discussions

Post by Indranil »

Sjha points out something that we had missed. Mark the maneuver at 10:58. It is a 180 degree roll plus a 90 degree turn in about 3 seconds.

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Re: LCA Tejas: News and Discussions

Post by JayS »

^^ hmm..that's interesting indeed.

I also liked the one at 11.20 onwards where it changes direction so sharply. With that kind of agility it could easily get through the traffic on old airport road better that I could on my bike. LOL

Tell me something, is it only me or LCA does display low roll rate in general?? I was expecting faster rolls somehow.

One more update from SJha:

Saurav Jha ‏@SJha1618 7m7 minutes ago Hyderabad, Andhra Pradesh
From my discussions over the last two years, I get the feeling that a 5-8 % reduction in aerodynamic drag for the Tejas may be possible.
Last edited by JayS on 29 Jan 2016 14:19, edited 2 times in total.
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Re: LCA Tejas: News and Discussions

Post by member_22539 »

^I think some of the older videos, particularly some with the view form inside the cockpit, show quick rolls.
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Re: LCA Tejas: News and Discussions

Post by Karan M »

>>>I also liked the one at 11.20 onwards where it changes direction so sharply. With that kind of agility it could easily get through the traffic on old airport road better that I could on my bike. LOL

:rotfl: :rotfl:

this could be a match winner for tejas...avoid traffic use tejas
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Re: LCA Tejas: News and Discussions

Post by JayS »

Karan M wrote:avoid traffic use tejas
ha ha. It will sell like hot cakes in Bangalore then.

BTW have a look at thi from SJha's article from 2014: http://www.ibnlive.com/blogs/india/saur ... 48651.html
The Mk-II design will specifically address the sustained turn rate (STR), climb rate and transonic acceleration shortfalls of the Mk-I. The ASR requires a STR of 18 degrees (same as the F-16's) and Mk-II will close in on that. The climb rate will also be more or less satisfactorily reached. Transonic acceleration is expected to be realized fully. Moreover the Mk-II airframe will certainly be able to reach and fly through Mach 1.8 in a dive.
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Re: LCA Tejas: News and Discussions

Post by Singha »

does the mirage2000 (the closest existing analogue of the tejas design) have a STR of 18?
else it is totally meaningless to compare to the F-16 in what it does best in the level plane-STR! we cannot take a union of the best of every design and expect anyone to match that. the F-16 tops off at mach1.8 - imagine if the usaf had taken a look at the mach2.2 mirage2000 and mandated it must meet that spec also.
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Re: LCA Tejas: News and Discussions

Post by maitya »

Singha wrote:does the mirage2000 (the closest existing analogue of the tejas design) have a STR of 18?
else it is totally meaningless to compare to the F-16 in what it does best in the level plane-STR! we cannot take a union of the best of every design and expect anyone to match that. the F-16 tops off at mach1.8 - imagine if the usaf had taken a look at the mach2.2 mirage2000 and mandated it must meet that spec also.
Singhaji, you can make up your own mind wrt M2K STR (and ITR) etc from this old post of mine ... btw, it has the F16 STR (and ITR) numbers as well.
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Re: LCA Tejas: News and Discussions

Post by Gyan »

Very soon LCA will be mandated to fulfill the requirements and match the performance of HDW submarine also.
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Re: LCA Tejas: News and Discussions

Post by Gyan »

India should sell LUH, ALH, LCH, HTT-40, IJT, LCA, Dorniers at "Marginal Cost" to our neighbors and friends in Region.
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Re: LCA Tejas: News and Discussions

Post by Singha »

far more useful than $100b US led aid programs. $95b of that is spent in a enormous green zone, logistical tail across the oceans, mobile burger king and so on....way too much expense ratio. we can go in light and give the afghans a lot of teeth with Rudra and Dhruvs for a start.
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Re: LCA Tejas: News and Discussions

Post by Bihanga »

Singha wrote:every significant aerospace power out there, as per its needs has a volume production of a basic type to fill the bulk of roles.
for US it was f-16. for china it is J-10.

the basic type must be 3:1 in numbers vs others to control costs.

36 rafale in 2 special bases is a soln to SL or BD going rogue, cheen will be :?:

its obviously a ploy to get +36 or +72(!) later once the foot is inside the door...and the GOI must not fall for this import lobby plan.
Correct me if am wrong, in my opinion Rafale is as important for India as Tejas in terms of fighting capability.

Part of the problem is development cycle of Tejas project which doesn't guarantee delivery of required Capability without cost escalation and timeline delivery. On the top of that, IAF force structure mandate lean and mean fighter jet inventory with limited budget. We are unlikely gonna put overwhelming numbers for mass attacks for atleast another decade because of slow pace of production like MKI which is still produced at 10 per unit since last 15 years, even then existing MKI fleet has operational readiness of 60 percent and not counting attrition because of engine troubles.

IAF is fully mindful of above hence pushing for Pricey Rafales which is mirror image of Mirage-2000 which guarantee quantem jump in terms of cutting edge technology and above 90 percent readiness against most likely opponents like J-10, Flankers and F-16 in our enemy inventory
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Re: LCA Tejas: News and Discussions

Post by Gyan »

BVR Issue.

The delay in firing BVR missile is all due to IAF. LCA is BVR capable but IAF specified the make of BVR missile i.e. Derby only in 2014. Integrating a specific BVR missile to an aircraft is non-trivial task. Apart from wind tunnel tests of safe separation at various speeds, configurations, turn rates, attitude etc, the software and electronics of BVR missile has to be integrated to work seamlessly with Aircraft's Radar, HUD, HMCS, HOTAS, MAAWS, Jammers, MFD, Comms, Data Links, INS etc. Integrating R-73 took 18 months. If ADA is able to integrate and fire a BVR missile in 2016 then it a major achievement.
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Re: LCA Tejas: News and Discussions

Post by JayS »

Some updated from LCA FB page:

- LSP1 might not fly again
- SP1 is hanger queen for a year now. Expected to resume flying soon. (I thought since IAF squadron formation has already started and SP1 must be used for flying).
Q: Has Tejas achieved STR of 18 deg/sec as described in ASR? or falls below it?
A: We're almost there with the ASR figure. :mrgreen:
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