LCA ground run & some other questions

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LCA ground run & some other questions

Postby Arun_S » 27 Dec 2000 12:54

While LCA is getting ready for maiden flight, couple of questions:<P><B>Question #1: </B>What is the enticipated takoff and stall speed for LCA ?<P><B>Question #2: </B>The LCA GTX Kaveri engine is supposed to have 8300Kg thrust. Now that India will make the AL-31F engines (weighing 1530 Kg) of Su30 rated at 8100Kg. Does anyone know the slated weight of GTX and the form factor(diameter, length etc) of the two engines ?<P>My guessestimate for the first question is that the stall speed and takeoff speed of LCA be similar (more likely lower) to Mirage-2000.<P>The second question also leads me to believe that:<BR>A. The Indian GTX Kaveri would finally come to fruitation due to the AL31F engine manufacturing knowhow (is part of the deep licence deal), which is in a way an insurance policy to GTX success. <P>B. From logistics perspective though it would make lot of sense to use the same SU30's AL31FP engine for LCA too, giving economies of scale to the most expensive part of the aircraft.<P>Your assessment and insight are welcome and appriciated.<BR>Cheers ... <BR>=========================================<BR>[url]<BR>First the news excerpt: <A HREF="http://www.hindubusinessline.com/stories/142704yb.htm" TARGET=_blank>http://www.hindubusinessline.com/stories/142704yb.htm</A>[/url]<BR><B><BR>LCA to undergo more ground runs</B><BR><I>BANGALORE, Dec. 26 <P>FOLLOWING the ground run held last week, the prestigious Light Combat Aircraft (LCA) will undergo three more ground runs, in preparation for its first flight which is likely to be held very soon. <P>Defence establishment sources told Business Line, that the high-level committee which met a couple of days ago, has certified the LCA's readiness to fly, after three more ground runs. <P>Indications are that the Defence Ministry wants the LCA to fly before the Aero India show slated in February, as the country's aeronautical development capability is at stake. <P>The speeds at which the ground runs for the LCA are conducted are being gradually increased until the LCA is taken up to 240 kms per hour speed. For instance, the first ground run was undertaken at 150 kms per hour. The second then would be at 200 kms per hour and the third at 220 kms per hour and the last 240 to 245 kms per hour. </I><P>=====================================<BR>[url]<A HREF="http://www.economictimes.com/today/in07.htm" TARGET=_blank>http://www.economictimes.com/today/in07.htm</A>[/url]<I><BR>......... Under the three-billion-dollar deal, India would be granted a "deep" license, which provides for the indigenous production of all components of SU-30MKI over a period of 20 years, including 'al-31fp' thrust-vectoring engines....... </I>

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Re: LCA ground run & some other questions

Postby Div » 27 Dec 2000 12:59

Arun,<P>The possible use of the AL-31 in the LCA makes sense...but I don't know if there will be any problems with the dimensions (could there be?).

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Re: LCA ground run & some other questions

Postby Avram S » 27 Dec 2000 13:42

Now that the LCA is going to take off sometime "quite" soon......here are my questions<BR>1) by the time it rolls out, would it be a little outdated?<P>2) by the time it rolls out, would it be a little too small to carry the demands of combat...high performance rockets, radar etc?<P>3) How soon would it take the MCA to evolve?<P>4) Or would they give up on the MCA due to the exhaustion caused by the LCA project?<P>Any current engineers/technicians or recent personnels involved in the project around to enlighten me?<BR>Dont worry guys, I am not collecting intel for anybody these days. Image<BR>Avram Sprinzl

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Re: LCA ground run & some other questions

Postby Vikram Rathore » 27 Dec 2000 13:59

Avram,<P>The LCA when it rolls out will definitely not be a match for a Su-30, or perhaps even an upgraded MiG-29. But it will serve two critical purposes:<BR>1) It will be far superior to the MiG-21 and also potential adversaries like the Mirage III, F-6/7, and give the IAF a firm numerical backbone to replace the aging MiG-21<BR>2) It will provide a firm base for future indigenous efforts.<P>Net, I would not judge the LCA too harshly- lets not compare it to a Su-30 or Rafale and trash it- it will play its own important role in the IAF when it enters service (touch wood).

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Re: LCA ground run & some other questions

Postby merlin » 27 Dec 2000 18:58

<I>>>Question #1: What is the enticipated takoff and stall speed for LCA ?</I><P>Judging from the article, more than 245 kmph. Image<P>According to an article I read earlier, the designers of the Kaveri had succeeded in reducing the weight of the Kaveri to 1150 kgs. from 1400 kgs. using FEA. Kaveri is reportedly undergoing tests in Russia and is delayed, so PV1 will also use the GE engine (like TD1 and TD2) instead of Kaveri as originally planned.<P>I'm guessing that AL 31FP is larger in size than the Kaveri (larger inlet diameter), therefore it may not fit in the LCA. It is heavier too and that may cause balance problems. The technology would be useful to have, nevertheless.<BR>

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Re: LCA ground run & some other questions

Postby geeth » 27 Dec 2000 20:30

In addition,there will be problems in redesigning the sir inlets, since the speed range of the two aircrafts are vastly different. To put it crudely, Su31 air intakes won't fit into LCA fuselge. Redesigning it would greatly affect the performance of the engine, since it would have been already optimised for the Sukoi engine.<P>There must be other factors as well which goes against this option.

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Re: LCA ground run & some other questions

Postby rama » 27 Dec 2000 23:45

The Kaveri has a thrust of 19,000 lbs (with afterburners) while the Al-31 is 27,000 *plus* so there is a mismatch! (likely to manifest itself in many ways such as size and inlet opening requirements). Other engines in the IAF inventory are more closer - such as the M53 of the Mirage2K (at 21,500 lbs) and the Klimov RD-33 turbofans of the Mig-29.<P>The latter is a much maligned engine in terms of operational reliability, but has been upgraded. Does it have FADEC though? If not, integrating it into the LCA may not be possible. Using the RD-33 will have the strong benefit of us killing the FC-1.

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Re: LCA ground run & some other questions

Postby Arun_S » 28 Dec 2000 00:10

Getting the thread back to the original questions:<P>Ground runs trials just before flight testing are done at speeds higher then the takeoff and landing speeds, basically to confirm aircraft handling for the obviously critical manouvers. The airplane does fly off the runway just few feet high. It certainly excercises the flight control surface & systems.<P>These speeds (i.e. 150 kmph to 240 kmph) are much higher to be below stall / landing speeds.<P>FYI the takoff speed and stall speed for Mirage-2000 is 138 MPH(209 Km/Hr) & 114 MPH(173 Km/Hr) respectively.<P>As I said my gut feeling is that for LCA the speeds be lower than that. The resons being LCA is smaller & ligheter, and its operating speed regiem is smaller then Mirage. Now does that mean the first Ground Run at 150 Km/Hr hit the LCA stall speed or takeoff speed ? I would think so.<P>On the Kaveri Engine weight of ~1150Kg is really good news. Ceratinly the SU-30 engine would bring to the table the diffcult to master compressor metallurgy knowhow to ensure the line production of Kavari engine goes smoothly then otherwise.<P>[This message has been edited by Arun_S (edited 27-12-2000).]<p>[This message has been edited by Arun_S (edited 27-12-2000).]

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Re: LCA ground run & some other questions

Postby Nandai » 28 Dec 2000 00:17

Guru, which parts of the Gripen are, as you say, "off-the-shelf", most of the systems used were developed from scrath, as far as I know anyway, and also, in what way are the Eurofighter and the Rafale more complex, other than that they use 2 engines.<P>------------------<BR>Nandai<P>Since time began,<BR>the dead alone know peace.<BR>Life is like melting snow.

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Re: LCA ground run & some other questions

Postby bobj » 28 Dec 2000 01:56

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Arun_S:<BR><B>Ground runs trials just before flight testing are done at speeds higher then the takeoff and landing speeds, basically to confirm aircraft handling for the obviously critical manouvers. The airplane does fly off the runway just few feet high. It certainly excercises the flight control surface & systems.<P>These speeds (i.e. 150 kmph to 240 kmph) are much higher to be below stall / landing speeds.<P>FYI the takoff speed and stall speed for Mirage-2000 is 138 MPH(209 Km/Hr) & 114 MPH(173 Km/Hr) respectively.<P>As I said my gut feeling is that for LCA the speeds be lower than that. The resons being LCA is smaller & ligheter, and its operating speed regiem is smaller then Mirage. Now does that mean the first Ground Run at 150 Km/Hr hit the LCA stall speed or takeoff speed ? I would think so.<BR>(edited 27-12-2000).]</B><HR></BLOCKQUOTE><P>So does this imply that some limited test-flights might have already taken place to atleast validate the flight control system? What you say seems to suggests that and I sincerely hope that that's true---a first test-flight failure would be a big disaster not only becuase of the loss of a valuable plane but possibly loss of a brave pilot and lot of lost of confidence.<P>Now how close is the Kaveri engine from completion? Isn't this the major limiting factor for production of LCA?<P><p>[This message has been edited by bobj (edited 27-12-2000).]

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Re: LCA ground run & some other questions

Postby Skanhai » 28 Dec 2000 04:49

How much of a flightcontrol system the LCA has?<BR>Since good old USA placed India under an embargo, the FCS had to be build in India while all the work done sofar was lost because the Indian engineers weren't allowed to bring back their own work.<BR>Or is it possible that the LCA will have coventional FCS instead of (a more complex) FBW system?

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Re: LCA ground run & some other questions

Postby JCage » 28 Dec 2000 05:00

..."Or is it possible that the LCA will have coventional FCS instead of (a more complex) FBW system?"<P>No chance ,as the a/c is "unstable"...it can fly only when the fbw is validated.A conventional electro-hydraulic system cant do nuts for the lca.<BR>

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Re: LCA ground run & some other questions

Postby Arun_S » 28 Dec 2000 13:00

<I>>>So does this imply that some limited test-flights might have already taken place to atleast validate the flight control system? </I><P>Similar to people doing aeromodelling with RC airplanes, the first things that you do on a new airplane design, is to just lift off ground the plane to know first hand the handling characterstics of the airplane, and then fly it available length of the runway without lofting it up in the air.<BR> <BR>For real airplane with pilots the amongst the first thing to know and make sure is its the landing charactersitcs within the safety of hard runway few feet below.

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Re: LCA ground run & some other questions

Postby Arun_S » 29 Dec 2000 00:23

Can someone lead me to Kaveri's & AL-31F vital statistics ? <BR>I.e. <BR>1. Air flow rate<BR>2. Inlet pressure<BR>3. Length<BR>4. Diameter<P>Thank you .....<BR>

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Re: LCA ground run & some other questions

Postby Nandai » 29 Dec 2000 02:15

Arun, I got the stats for the AL-31, not the Kaveri though. Im not a techie, so I will just give you the figures in the latest MilTech, hope they will do Image<P>Thrust, dry - 83.4 kN<P>Thrust, a.b. - 142.2 kN<P>Thrust-to-weight ratio, dry/a.b. - 5.1/8.7<P>Massflow, not available<P>Overall pressure ratio - 25<P>BPR - 0.65<P>Dimensions, diameter x length, 1227mm x 5350mm<P>Weight - 1660 Kg<P>Figures for the SU-30MKI<P>

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Re: LCA ground run & some other questions

Postby bobj » 29 Dec 2000 03:20

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by spandya:<BR><B>Just read this... <A HREF="http://www.timesofindia.com/today/29mban1.htm" TARGET=_blank>http://www.timesofindia.com/today/29mban1.htm</A> </B><HR></BLOCKQUOTE><P><BR>Ummm...by Dec 31 or by Jan 10th, now these are definite targets. I just hope they do this by Dec 31. It would be a nice way to start the new year.<BR>

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Re: LCA ground run & some other questions

Postby rama » 29 Dec 2000 04:01

Nandai, <P> The Kaveri is in the thrust class of the GE F404 or the Turbomeca M88 and so posting those figures may help if you have acess to them. Kaveri is still in development and so figures may be hard to come by....

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Re: LCA ground run & some other questions

Postby Arun_S » 29 Dec 2000 05:20

<B>Raj:</B><BR>FYI, typical IAF runway length is 9000 ft ( almost 3 Km). IIRC the Banglore runway is much more than that.<P><B>Nandai, shailesh.garg & Rama: Thanks for your input.</B><P>So far the following parameters are confirmed:<P><B>KAVERI:</B><BR>Air-mass flow : 78 kg/s <BR>Dimensions, diameter x length: ? x ?<BR>Inlet pressure at input of 1'st compressor blade : ?<BR>Overall pressure ratio : 21.5 <BR>By-pass ratio : 0.16 <P><B>AL-31F</B><BR>Air-mass flow : ?<BR>Dimensions, diameter x length, 1227mm x 5350mm<BR>Inlet pressure at input of 1'st compressor blade : ?<BR>Overall pressure ratio : ?<BR>BPR - 0.65 (conversly it is 0.35)<P>Am trying to see how close the two engines are for viability of substitution. Getting GE 404 /Turbomeca M88 data instead of Kaveri would be very useful. <P>I am not deterred by the jet intake size argument, because the outer appearence of jet intake can be misleading, what matters is the shockwave compressed gas reaching the compressor input at ~ sonic to supersonic speed and the airmass flow. If that is in acceptable range, then physical size need be accomodated. The By-pass-ratio (BPR) difference is not a big deal.<P>Please keep helping me with the data. <P>Cheers ....<P><p>[This message has been edited by Arun_S (edited 28-12-2000).]

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Re: LCA ground run & some other questions

Postby rama » 29 Dec 2000 05:52

Here's some on the GE F404-F2 which the LCA uses on TD-1/2/PV-1:<BR>_____________________________<BR>Specifications: F404-GE-402<P>Thrust (lb) 17,700<BR>Airflow (lb/sec) 146<BR>Weight (lb) 2,282<BR>Maximum Diameter (in) 35<BR>Pressure Ratio 26 to 1<BR>_____________________________<P>Taken from: <A HREF="http://usfighter.tripod.com/frames1.htm" TARGET=_blank>http://usfighter.tripod.com/frames1.htm</A> <P>Note that the F404 has a higher pressure ratio. Comparing the diameters of the F404 (35 inches, 890mm) to that of the AL-31 (1227 mm) indicates that atleast some major airframe redesign may need to be done to accomodate the latter. Just as well, since the AL-31 seems to be around 630 kgs heavier at 1660kg vs 1030 kgs. Compared to the total empty weight of the LCA at around 5500 kgs, it is easy to see that the center of gravity will move quite a bit! It may just be easier to scale the design up - which will throw the schedule out once more Image<P>

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Re: LCA ground run & some other questions

Postby Arun_S » 29 Dec 2000 06:30

While weight is an issue, the impact on Center of Gravity can be handled by moving the wing aft in post TD1/2 frames. IIRC that is a standard procedure for commercial aircraft industry. Pending other engine parametrs, the 30% more diameter is more the issue. Though the bigger diameter is also due to its higher bypass ratio, which incidently gives better subsonic performance.<P>If one gets the length parameter the CG can be quantized for impact.<P>

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Re: LCA ground run & some other questions

Postby Roop » 29 Dec 2000 11:30

I have a bottle of champagne cooling its heels in my fridge, waiting for the LCA's first flight. Image

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Re: LCA ground run & some other questions

Postby Nandai » 29 Dec 2000 16:55

Rama, does that mean that the Kaveri might have similar dimensions to that of the M-88? Cause I got those if anybody needs them.<P>Dimensions of the Snecma M88-2, 820mm x 3540mm.<P>About the AL-31s airflow, the performance in the other parameters seem to be just above those of the GE F110-129/132, and the airflow of that engine is 122.5Kg/s for the -129 and 125Kg/s for the -132, could it be that the airflow for the AL-31 is something like 130-135Kg/s?<P>------------------<BR>Nandai<P>Since time began,<BR>the dead alone know peace.<BR>Life is like melting snow.

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Re: LCA ground run & some other questions

Postby Avinash » 29 Dec 2000 17:08

Does anyone have any information about the progress being made in to Asta AAM being designed for the LCA and other aircraft of the IAF?<P>------------------<BR>Y.Avinash

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Re: LCA ground run & some other questions

Postby geeth » 29 Dec 2000 23:03

IIRC the length of the runway at HAL/NAL is about 11,000 ft and is one if the longest runways in India.<P>About Kaveri, the production version is supposed to have an overall pressure ratio of 27:1 - I don't know why the protopytes will have only an overall pressure ratio of 21.5.<P>anyway, the first thing is to get the a/c airborne see to it that it flies for a few minutes!<P>God bless!!

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Re: LCA ground run & some other questions

Postby Arun_S » 30 Dec 2000 11:42

So far the engine diameter appears to an issue with ~25 cm difference.<BR> <BR>The airflow rate for AL31F is still unknown. The guessetimate of ~130Kg/sec does not jive well with flowrate of the thrust rating of Kaveri & F404 which are of otherwise compareable thrust. It is plauseable that Bypass Ratio of 0.65 & 0.16 may be the source of the airflow discrapency. <P>However if the airflow rate of AL31F is indeed beyond 25% range of KAVERI or F404, then it will be a dead end. I look forward to any data on AL31F for the purpose.<P>The current updated parameters are:<P><B>KAVERI and/or F404/M88-2:</B><BR>Air-mass flow : 78 kg/s <BR>...................{F404: 66 Kg/s} <BR>Dimensions, diameter x length: ? x ? <BR>........................{F404: Dia- 890mm, Length- 4030mm}<BR>........................{Snecma M88-2: Dia- 820mm, Length- 3540mm}<BR>Inlet pressure at input of 1'st compressor blade : ?<BR>Overall pressure ratio : 21.5 {F404: 26}<BR>By-pass ratio : 0.16 <BR>........................{F404: 0.27)<P><B>AL-31F</B><BR>Air-mass flow : ? {Guesstimated ~130 Kg/sec}<BR>Dimensions, diameter x length, 1227mm x 5350mm<BR>Inlet pressure at input of 1'st compressor blade : ?<BR>Overall pressure ratio : ?<BR>BPR : 0.65 <P><p>[This message has been edited by Arun_S (edited 31-12-2000).]

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Re: LCA ground run & some other questions

Postby Nandai » 30 Dec 2000 17:37

The GE F404-402 is 4030mm long, weighs 1035Kgs and has a BPR of 0.27.<P>------------------<BR>Nandai<P>Since time began,<BR>the dead alone know peace.<BR>Life is like melting snow.

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Re: LCA ground run & some other questions

Postby Arun_S » 01 Jan 2001 09:13

So any takers on the LCA's stall speed ?<P>On the Engine substitution here my take currently.<P>The core airflow rate of :<BR>Kaveri is 78 / (1 +0.16) = 67.2 Kg/sec.<BR>F404 is 66 / (1 +0.27) = 52.0 Kg/sec.<BR>AL31F is 130 / (1 +0.65) = 78.8 Kg/sec {assuming 130 Kg/sec Guess-estimate)<P>Thus the AL31F core is 17% more them Kaveri and 52% more then F404 (of course based on the 130 Kg/sec guessetimate of AL31 flow rate). That does not bode well for the possibility of substituting the engine. However we still need to know the published flow rate of AL31F to be certain of above figures. If the flow rate is in the ballpak then subsequent drivation of the design for lower bypass ratio is possible. As I said before the key advantage will be exconomies of scale if LCA & SU30 use the same engine core.<P>Cheers ... & Happy New Year.<BR> <P>

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Re: LCA ground run & some other questions

Postby geeth » 01 Jan 2001 12:48

Arun-S,<P>How do you propose to solve the large diffenrence in the air flow (130 kg vs 78 kg)? Won't the SU engine be starved off air if its is used in LCA without redesigning the air intakes? (In addition there would be problems with shock formation at the air inlets-very different flight characteristics). The engine lengths are quite different, resulting in drastic reduction in capacity of the internal fuel tanks of LCA. Also, the engine mountings will have to be redesigned altogether. <P>What is the need to derate an engine to to conform to the requirements of LCA?<P>There will be some economic gains by using the same engine in both LCA and SU31, but IMO the technological hurdles that are required to be crossed will offset these gains.

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Re: LCA ground run & some other questions

Postby Nandai » 01 Jan 2001 19:08

Okey, our guess was off by 500Kgs, but thats pretty good anyway, here is a link to a page where it says that the AL-31F has a thrust of 12500Kgs.<BR> <A HREF="http://www.armscontrol.ru/atmtc/Arms_systems/Avia/Russia/Sukhoi_Aircraft.htm" TARGET=_blank>http://www.armscontrol.ru/atmtc/Arms_systems/Avia/Russia/Sukhoi_Aircraft.htm</A> <P>------------------<BR>Nandai<P>Since time began,<BR>the dead alone know peace.<BR>Life is like melting snow.

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Re: LCA ground run & some other questions

Postby shashidhar » 01 Jan 2001 20:20

Despite all this deadlines LCA sits like a wingless bird Image

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Re: LCA ground run & some other questions

Postby jayam » 01 Jan 2001 21:40

I was about to ask the same question. Any news on the first flight? Did it happen?

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Re: LCA ground run & some other questions

Postby Nandai » 01 Jan 2001 23:19

No, it hasnt flown yet.<P>------------------<BR>Nandai<P>Since time began,<BR>the dead alone know peace.<BR>Life is like melting snow.

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Re: LCA ground run & some other questions

Postby Arun_S » 02 Jan 2001 01:43

<I>>>How do you propose to solve the large diffenrence in the air flow (130 kg vs 78 kg)? Won't the SU engine be starved off air if its is used in LCA without redesigning the air intakes? </I><P>To clear the air let me say that I am not jet engines pro/expert, but can hold on my own. <P>Clearly a straight replacement of KAVERI by AL31F requires engineering changes which should/could not be considered viable in the initial short term, certianly not in the next 10 builds. However what is very viable and compelling is to use the same jet engine core, which is the core-technology( BTW the air-intake of the core is only 17% more for AL31F w.r.t. KAVERI. Corresponding to 8% higher diameter). The peraphenalia around the core is mostly related to air bypass ratio. The Air-bypass generally increases the diameter of the engine (at the intake compressor), and it is used to consumate excess power of the jet core. <BR>Certainly changing the BPR changes the engine. IMHO the possibility is to use the AL31F core technology in quickly developing KAVERI-II or if you like AL31F-II engine re-using all components of the AL31F core, thus reducing parts inventory in field and reduced cost by higher volume production. <P>Like any new airplane LCA will go through a re-design phase after the inital builds, and the issue of engine weight,volume and intake layout may be factored in at the time. <P>On the time line the AL31F for SU30 is unlikely to be made in India in next 2 year, so in my view this project is only viable in medium term. <P>In a way LCA & Su30 together has happend at a good time. Indian KAVERI has made a name for itself, but in my view it is essentially a technology demonstrator, Indian ability to get it to manufacture it consistently is unproven, the AL31F local manufacturing will cement that capability gap at just the right time.<P>Cheers ....<BR><p>[This message has been edited by Arun_S (edited 01-01-2001).]

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Re: LCA ground run & some other questions

Postby jayam » 02 Jan 2001 10:10

An News item by Janaki Murali on the upcoming AeroIndia'2001. Interestingly, there is no reference to LCA at all in this article. mmmm... Hope we will hear some good news soon.<P> <A HREF="http://www.hindubusinessline.com/stories/14020427.htm" TARGET=_blank>http://www.hindubusinessline.com/stories/14020427.htm</A>

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Re: LCA ground run & some other questions

Postby bobj » 02 Jan 2001 22:16

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by R.Singh:<BR><B>That was 2 weeks ago!!! check BR news archive on Indian air force. You'll see an article, "LCA, akash and trishul facing more delay" <BR></B><HR></BLOCKQUOTE><P>Yes, but the promise of imminent flight test were announced only late last week. Although we know that the Dec 31st deadline has been missed, this was not a deadline, Jan 10th is the deadline although defence ministry would have like it to happen before the end of the year to put an end to speculation. I am still caustiously optimistic of a flight test in the 1st half of Jan.<BR>

rama
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Re: LCA ground run & some other questions

Postby rama » 02 Jan 2001 22:17

Arun_S,<P> Got it now! Re-using engine cores is fairly common practice - there are instances of commercial aircraft turbofans "derived" from succesful combat aircraft engines.<P> But got to wonder - won't it be simpler to scale up the LCA to fit the engine - the French have done this a couple of times in the Mirage family (with experimental versions, and also for the F-1C which started it's program life with a much bigger engine). Afterall designing/redesigning an engine is atleast as much non-trivial work as doing an airframe.<P> Incidentally the Chinese are way ahead on this - both their J-10 and Flankers use the Al-31F....

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Re: LCA ground run & some other questions

Postby Varun Shekhar » 03 Jan 2001 14:52

<BR> LCA set to fly on Thursday!!(as in tomorrow)<P>According to this article...<BR> <A HREF="http://www.vigyanprasar.com/news/newsdet.asp?newsdate=1/3/2001&newsno=4" TARGET=_blank>www.vigyanprasar.com/news/newsdet.asp?newsdate=1/3/2001&newsno=4</A>

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Re: LCA ground run & some other questions

Postby Raj Malhotra » 03 Jan 2001 22:56

Su-30 deal is supposed to be deep technology t/f deal. Does it include transfer of radar tech also? If yes, Is the radar tech worthwhile coming from Russia which does have some laggings in the said field?<P>I hope one does not find my raising this issue out of context in this thread! [as ALH flew in 1992(?) and see where is its combat electronics suit].

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Re: LCA ground run & some other questions

Postby Arun_S » 04 Jan 2001 01:10

This seems to confirm some the discussion on this thread. <BR> <A HREF="http://www.rediff.com/news/2001/jan/03lca.htm" TARGET=_blank>http://www.rediff.com/news/2001/jan/03lca.htm</A> <P>India to test-fly LCA in 'couple of days': AFP<P>..... "The hope is that the Sukhoi technology can be incorporated in the LCA design," Bedi said. <P><B>Varun Shekhar:</B> What a great news. "Tere muh mai gud shakker" !! Image Image So the nose lifted off without flaps.<BR> <A HREF="http://www.vigyanprasar.com/news/newsdet.asp?newsdate=1/3/2001&newsno=4" TARGET=_blank>http://www.vigyanprasar.com/news/newsdet.asp?newsdate=1/3/2001&newsno=4</A> <P>... told Deccan Herald here today that high speed taxing conducted during last fortnight in a hush-hush manner, has been successful with LCA successfully lifting on its nose wheel (virtually in the air and short of actual airborne flight) on Sunday. Stating that the aircraft floated on its two rear wheels as the flaps were not operated, in which case, it would virtually lift off, sources said, LCA should<BR>have actually made its maiden flight on Sunday had not weather played truant and for some minor leaks....<P><BR><I>>>Su-30 deal is supposed to be deep technology t/f deal. Does it include transfer of radar tech also? If yes, Is the radar tech worthwhile coming from Russia which does have some laggings in the said field?</I><P>I do not know for sure if the RADAR tech will come with deep licence. Can someone confirm/deny that ?<P>Certainly, apart from the SU30 engine, other stuff of interest is certainly the SU30's Radar. IIRC India does not yet have airborn radar capability, there is lot to learn and catch up using the SU30 radar. Its better to first learn to run before leaping to be the absolute best.<P>Three Cheers ........

rama
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Re: LCA ground run & some other questions

Postby rama » 04 Jan 2001 02:10

The multimode radar intended to go into the LCA is definitely an Indian design and has been tested on Mig21 and HS748 testbeds in flight according to news reports from a couple of years ago. It is a conventional mechanically scanned pulse doppler radar, and not a phased array like the Phazotron Zhuk. The Zhuk may be the radar of the Su-30MKI ( only place I've seen this positively mentioned is a website), so there is some radar technology to acquire from the Su-30 too...<P>


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