LCA News and Discussions, 22-Oct-2013

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Victor
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Re: LCA News and Discussions, 22-Oct-2013

Postby Victor » 02 Jan 2015 00:20

Here is an engine simulator that allows one to examine the effect of inlet design on engine performance.

Another factor that I remember reading about is the location of the inlet itself. The airflow around a maneuvering aircraft will have a varying effect on the amount of air and its speed reaching the compressor face depending on the inlet design. The Su30, Mig29 and Hornet have long leading edge extensions with the engine placed well back on the fuselage while the Mirage 2k has them well in front of the wings to obviate any interference. The Rafale has a scoop-like design under the canards that seems to isolate and protect the inlet from control surface turbulence. The LCA has them almost right underneath the leading edge root which I haven't seen in other modern jets yet (which is not saying a lot since I don't ogle airplanes like I used to do). Nevertheless, there must be a relatively cheap and simple test, maybe in a wind tunnel, that will once and for all settle the question and remove a nagging issue given the critical effect it has on engine performance.

Indranil
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Re: LCA News and Discussions, 22-Oct-2013

Postby Indranil » 02 Jan 2015 00:50

maitya wrote:The mass-flow for Kaveri and F414 are same ~78kg/s and though I don't know (off-hand) the inlet-diameter of Kaveri, it shouldn't be too different from that of F414 (given they both same handle mass-flow and also assuming they would allow similar engine-entry velocity of say ~0.6M).
So, IMO, the air-inflow design shouldn't require too much of a change - apart from removing/re-adjusting what ever "narrowing" etc they would have done to reduce the mass flow to ~69kg/sec for F404.

Do note the inlet diameter diff between F404 and F414 (to account for this larger massflow of approx 10kg/sec) is approx 3inches - so for a similar mass-flow-of-Kaveri similar inlet dia should have been provisioned for in the original LCA design.

Yes, it seems the airflow and inlet diameter of Kaveri is very similar to the 414, and not the 404. Therefore, the original inlet designed for the Kaveri would work really great for the 414. However, for 404, if the mouth of the inlet remained the same but the end of the inlet became much narrower; then unless the whole of the inlet is redesigned to maintain the convergence-divergence effect, the pressure recovery would not be sufficient (as ex. Cmde Khokhar alleges). Don't you agree?

maitya wrote:However this provisioning for inlet dia etc is less impportant, from airframe structural design perspective, compared to fitting-in the max-width of the engine ... typically they are an order of magnitude more. For e.g. for both F404/F414 the max-engine width is ~890mm (compared to 910mm for Kaveri).

Similarly, length wise Kaveri (at 3490 mm) is ~40cm shorter than both F404/F412 (at 3912 mm) - but if the current TDs/PVs/LSPs/SPs are able to accomodate for these ~40cm addn length of the F404, it should be able to accomodate the F414 of the same length.
Moreover there's minimal 10Kg weight difference between Kaveri (design weight of 1100Kg) and that of F414 (F404 is lighter at 1036Kg).

So IMO, structurally fitting in F414 may not be such an issue.

However, even slight change in CG position may not be that easy to adjust (as you have point out). But we don't know enough about where is the CG of F414 (vis-a-vis that of F404) located to do that kind of analysis - however, generally speaking, the heaviest aspects of a turbofan are the Fan, followed by the LP compressor stages, so the CG should be towards the "forward portions" of them.

I have no problems with the structural fit of the 414 inside the Mk2. It will fit. I am only talking about the length of the inlet. The end of our inlet is tied to the intake of the engine, and since the 414 is the same length as the 404, the end of inlet is equidistant from end of the plane in Mk2 as in Mk1. The front of the inlet is tied to the leading edge of the wing which in turn is tied to the C.G. of the aircraft*. Now Mk2 is lengthier than Mk1, hence the C.G. of the plane is likely to be more distant from the end of the plane**. Therefore the length of the inlet is likely to increase. Don't you think so?

* 1. The mouth of the inlet is tied to the leading edge of the wing, because of the spill duct, which I think needs some work too, that's for another post
2. The wing travels with the C.G. because the C.G. coincides with 33% of the MAC of the wing.

** Unless, they can add the body plug and still redistribute the weight in such way that C.G. of the plane doesn't travel with respect to the tail end of the plane.

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_28911 » 02 Jan 2015 01:05

@Saurav Jha:
4. Fighters: Major blue print for public-private approach for producing the Tejas Mk-II being readied. Potential game changer.

:mrgreen:

Indranil
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Re: LCA News and Discussions, 22-Oct-2013

Postby Indranil » 02 Jan 2015 02:57

Victor wrote:Here is an engine simulator that allows one to examine the effect of inlet design on engine performance.

Another factor that I remember reading about is the location of the inlet itself. The airflow around a maneuvering aircraft will have a varying effect on the amount of air and its speed reaching the compressor face depending on the inlet design. The Su30, Mig29 and Hornet have long leading edge extensions with the engine placed well back on the fuselage while the Mirage 2k has them well in front of the wings to obviate any interference. The Rafale has a scoop-like design under the canards that seems to isolate and protect the inlet from control surface turbulence. The LCA has them almost right underneath the leading edge root which I haven't seen in other modern jets yet (which is not saying a lot since I don't ogle airplanes like I used to do). Nevertheless, there must be a relatively cheap and simple test, maybe in a wind tunnel, that will once and for all settle the question and remove a nagging issue given the critical effect it has on engine performance.

Victor sahab,

You picked out the features properly, but not the use. None of the planes, use those features for better inlet efficiency. Infact they are a deterrent. If you want to see the most efficient layout of an engine inlet, look at the commercial jets. The cleaner the air you can get, the better. Hence the engine intakes are ahead of the wing. Even in fighters, nobody uses the turbulent air from anywhere near the surfaces of the plane (called boundary layer). This why there are splitter plates and DSI. By the way, LCA uses the boundary layer in one of the most innovative ways that I have seen so far to increase AoA and decrease drag.

The features, that you mention are used for ramming air into the inlet at low speeds and high AoA. Even LCA uses this. What you feel is that LCA's inlets are not sufficiently behind the leading edge of wing to use this effect. But this is not true. In real practise, the air does not start to move at the leading edge, but ahead of it. The faster you go, the further away from the leading edge does this effect start. What's more, if you look at this envelop of air moved by the leading edge, the outermost air is the most streamlined, and the inner most (near the aircraft surface) is most turbulent. The LCA inlet is therefore specifically designed to capture the outermost part of this airflow. It is actually quite evident if you have seen airflow around wings at different AoA and speeds. One does not need a simulator to verify this (although LCA designers must have used wind-tunnel models and simulators to optimize this). All the other aircrafts and methods that you wrote about also use this in one form or another. But not all of the air forced by the body/scoop/wing can be used by the inlet at all parts of the flight envelop. The inlet is designed to take in as much air as the engine needs to working properly (long discussion for some other time). The rest will be 'spilt' out and adds to the drag. All aircrafts are optimized around a 'design-point'. It is the pilot's responsibility to fly the plane at that point to extract maximum efficiency (and hence combat-edge) from the aircraft. The same goes for LCA, as any other aircraft*.

This is why you would never hear anybody (knowledge-able) crying about how much air LCA's intake is providing to the engine during aerobatics. The only question is how it is being provided (temperature, speed and pressure). This defines whether the maximum potential of the engine (with respect to thrust) can be exploited or not. Whether this is happening or not is not known in public domain. (ex)Cmde. Khokhar suggests that this is not happening with the 404. Dr. Tamilmani says that since the inlet was designed for Kaveri which is very similar to the 414, the intake does not need any changes, and would be more efficient with the 414.

* By the way, you were also wrong about the Mig-21 and Phantoms. In this case, direct aerial duels are available historically from the Vietnam war. The Mig-21 fighters tried to take the aerial battle to higher altitudes and faster speeds (their design point), while the Phantoms tried to take the duel to their designed advantage long and slow-tight turns (by virtue of better TWR). Often pilot skills and luck determined the results.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Karan M » 02 Jan 2015 03:07

Indranil, interesting point is that LCA is designed to 'drop in' for the MiG-21 per IAF specifications. Apparently, it had to fit in every infra for the MiG-21 fleet, from HAS to airstrips to regular shelters. Most of the decisions were constrained by those dimensions.

Including packaging all sorts of stuff into an airframe that size.

ADA had a lot of initial work with Dassault & parcels went to other firms as well. I guess none of them said "impossible" as even they didnt have the experience, nor did ADA and we ended up shooting for the stars.

With MK-2 wisdom seems to have kicked in (with IAF as well) and the 0.5 mtr extra should go a ways in reducing drag, improving the fuselage shaping. I seriously think there should be a MK3, where the IAF drops the entire MiG-21/LWF constraints altogether and we make our own F-16/J-10 sized platform. Even in an era of stealth, it will be very useful and can replace the earlier MK-1s and older MK-2s, building up the numbers to complement the heavies.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Cosmo_R » 02 Jan 2015 03:54

Ankar wrote:@Saurav Jha:
4. Fighters: Major blue print for public-private approach for producing the Tejas Mk-II being readied. Potential game changer.

:mrgreen:


Any specifics re PPP?

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Re: LCA News and Discussions, 22-Oct-2013

Postby Indranil » 02 Jan 2015 04:16

Karan,

No questions on the need and utility of LCA Mk1 and Mk2. People who harp on inducting only fifth generation fighters from now on are clearly detached from current reality. They need to be shown what the airforces around the world are currently inducting. And for India, what is relevant is what is PLAAF and PAF inducting. To induct and maintain 5th gen fighters for the next 50 years is financially intractable. And I say this in spite of being one of the biggest fanboys of the F-22. Unfortunately, USA paid the price for the whole world to learn.

Also, I do agree with you on the need for an Mk3, but I don't agree with your version. A F-16ish Mk3 is too close to the AMCA IMHO. Also, once you change the class of engines, aerodynamically and structurally it is almost like a new design. My version of Mk-3 is semi-stealth using practical methods like those suggested for the F-18 or one of the contenders for the KFX-E program.

Image

Give the airframe stealth shaping wherever possible without much effort. If possible add conformal fuel tanks. Otherwise shape the fuel tanks like the stealth weapons pod suggested for the F-18. Also, recess the pylons (as in the EF) and create stealth weapon pods.

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Re: LCA News and Discussions, 22-Oct-2013

Postby brar_w » 02 Jan 2015 04:18

kmkraoind wrote:
Saurav Jha ‏@SJha1618 Here's an early rendering of the LCA from AW&ST sporting a cranked delta wing via Elider at SecretProjects.


Image


On the history, here is an article from IDR/Janes dating back to 1989:

INDIA'S LIGHT COMBAT AIRCRAFT


Considering that India has to date designed indigenously no aircraft more advanced than the transonic HF‐24 Marut (first flight in 1961), taking on a project as advanced as the Light Combat Aircraft (LCA) might seem at first sight a trifle ambitious. The LCA is very roughly comparable to the Swedish Gripen, with the significant difference that while the Gripen has a US F404/RM12 engine, the LCA will have the totally indigenous GTX‐35VS. Considering what difficulties highly experienced Saab‐Scania has had with the Gripen, one can be forgiven for wondering whether the Indians are not biting off more than they can chew. Designing a brand‐new aircraft, to be powered by a totally new engine, is a formidable task.
It stands to the credit of the Indian design team, headed by Dr Kota Harinarayana of the Aeronautical Development Agency(ADA), that the work has progressed fairly smoothly so far. To recap the position, the project was first suggested in 1978 and given the go‐ahead in July 1983. Feasibility studies, awarded the same year to MBB, Dornier, Dassault‐Breguet and British Aerospace, were over in 1985, when the IAF Staff Requirement was issued.
The pre‐design phase began in 1986, followed by the start of the project‐definition phase with technical consultancy from Dassault. That work is now over and the configuration, dimensions, weight and performance envelope have been finalised. The first flight is now expected in 1992, with entry into squadron service in 1996‐97.
The project is now in the more difficult detailed design and engineering phase, for which a consultant may again be appointed. Dassault is keenly interested, and so is MBB, but the Americans are going all‐out to win and India finds American technology more advanced. A letter of Offer & Acceptance was signed by the two countries last October. Moreover, technical, logistical and infrastructural assistance will be available to India from the Wright Patterson laboratory as well as from the US manufacturers. Consultancy is also likely to be required in specialised areas like fly‐by‐wire.
The US Government has already cleared the transfer of several advanced technologies to India, such as primary composites from Northrop and flight‐control equipment technology from Allied Signal. Others, including fly‐by‐wire, cockpit displays and ring laser gyros, have either been cleared or are under discussion.
Few contracts for equipment and systems have been awarded, however. Some of the earlier ones are for 11 General Electric F404‐F2/J3 engines for the first six prototypes before the GTX is available. HAL's Hyderabad Division is working on a multi‐mode radar for the LCA, with assistance from Ericsson and Ferranti. It will be based on the Ericsson PS‐05 for the Gripen. Dowty‐Smiths Industries have had a contract some time back to develop a FADEC for the GTX‐35VS. Among indigenous items, HAL's Avionics Division is working on a secure V/UHF integrated communications equipment for the LCA. Additionally, HAL may licence‐produce equipment like a HUD, a threat‐warning system and twin 5in multi‐function displays.
The LCA is being designed as a light, advanced, single‐engined air‐ superiority aircraft with a good secondary ground‐attack capability. About the smallest such aircraft being developed anywhere in the world, it will be highly agile at subsonic speeds and will have supersonic manoeuvrability. An unprecedented 34 per cent of its fuselage structural weight will be in composites, and a special composites facility is to be set up to fabricate large structures. Composite components will include the wing, vertical fin, wing and tail moving surfaces and parts of the fuselage. Aluminium‐lithium alloys will also be used, and the National Aeronautical Laboratory was recently asked to evaluate the fatigue and fracture properties of commercially available alloys.
A recently released illustration of a wooden wind tunnel model shows bifurcated air intakes at the lower wing‐body junction as in the Rafale probably a Dassault contribution. These intakes will be of fixed geometry, and LCA performance may thus be limited to about Mach 1.6. The compound delta wing has a conical camber and very large moving surfaces all along the trailing edges, for high agility as well as good runway performance. Wing‐body integration is evident in the photograph. A significant omission is the canard foreplanes, which were eliminated at an early stage in the design process perhaps for the first time on a combat aircraft of such characteristics.
While no armaments have been announced, one good possibility is the recently announced Astra air‐to‐air missile under development at DRDL. The LCA will have a total of seven external attachment points. There appears to have been no effort to incorporate stealth technology. Production of the LCA will be at a totally new LCA complex to be set up at Bangalore.
Apart from the IAF, the LCA will also have a carrier‐based version for the the Indian Navy that will be based on the planned 30,000t‐ class sea‐control ships to be designed in India with the help of technical consultancy from SOFMA of France. These ships will incorporate for the first time a ski‐jump ramp (for Sea Harriers) as well as the steam catapult (for LCA) together on one ship.
Total project cost of the LCA is estimated at Rs20,000 million, though this could well be exceeded, and unit cost is pegged at "half that for the Rafale and EFA." Total expenditure so far is Rs1,322.6 million.
Whether the LCA can enter service even by the revised schedule of 1996 will depend on how rapidly the GTX engine can be fully developed and productionised. Understandably, there have been problems and delays, for which consultancy is being obtained from GE and SNECMA. Speaking to IDR, Jay Browne of General Electric said the a GE team had been to India in March 1989 and had been asked by the Government for its evaluation of the status of the GTX program, and advice for the future as overall consultants. This advice has been given in a number of areas component development, test plan, management structure and so forth.
Commenting on the work to date, Browne said he was very impressed with the basic design, conceptual approach and engine layout. "It is a very ambitious project," he emphasised, and added: "We are impressed with the talent and capabilities of people working on gas turbines in India."
Asked about the very long time taken for the first engine to run at 100 per cent rpm, Browne said this was not unusual for a brand‐new engine. He emphasised, though, that there were no plans for any development activity at the moment.
With SNECMA, relations are rather different. Bernard Templier, group manager for international affairs, emphasised that simple technology transfer was only one part of the arrangement. "We would prefer long‐ term co‐operation, lasting 12 to 15 years," he emphasised. "A common team of engineers could work on a common program, employing SNECMA technology to develop the GTX," he added. Templier talked in terms of "a considerable redesign" of the GTX and said the design was not finalised, anyway.
Among the specific areas of interest Templier mentioned the forging of components, particularly compressor blades, and their finish, where SNECMA technology is much advanced, the lost‐wax process of casting components like turbine blades, and even compressor design, based on M88 experience.
What SNECMA would like to have is long‐term co‐operation. "If we have a common program, we shall be willing to support its exports sales as well," Templier said. There is no such active co‐operation with India in any field as yet. This proposal of SNECMA is along similar lines to that of Hugues de l'Estoile, Dassault's senior vice president for international affairs, which he made during an interview with IDR (10/88 p.1336).
Incidentally, Templier also mentioned that should India select the Alpha Jet for the IAF advanced trainer requirement, SNECMA would be willing to transfer a large part of the production of the Larzac engine to India. He said that HAL was keen to have the technology of the new blades, and SNECMA was ready to have these produced at its foundry (which has 20‐year‐old technology, he added).


Another from 1988 (Janes Defense Weekly)

DASSAULT TO MARKET INDIA'S LCA


DASSAULT has a 'company‐country' agreement with the Indian Government to market Hindustan Aircraft Ltd's (HAL) Light Combat Aircraft (LCA) in certain areas, said Dassault officials at Farnborough air show.
Senior Vice President Research, Engineering and Cooperation, Bruno Revellin Falcoz, told JDW that LCA was now in Dassault's product spectrum, complementing other aircraft in the company's inventory.
The LCA will fit between fighters in production and proposed, such as the Mirage 2000, 4000 and Rafale, and the Franco‐German Alpha Jet.
"It is in the common interest of the Indian Government and ourselves," Senior Executive Vice President International Affairs, Hugues De L'Estiole added. "First the aircraft must meet the Indian Air Force's requirements, then those of other countries. We have to promote to those countries in common," he said.
Dassault has provided design assisistance to HAL for the LCA, bringing Rafale‐derived technology to the Indian company.
Company President and Chief Executive Officer, Serge Dassault, said he was confident about the ultimate success of Rafale, for which partners are still being sought in Europe and elsewhere, although officials declined to name those non‐NATO countries being wooed.
Rafale's full‐scale development was launched in April, when the Avion de Combat European consortium, in which Dassault is the principal player, was awarded a contract by the French Government to develop five prototypes for both tactical and naval roles.
Despite on‐going efforts on the part of the United States Government to entice the French Navy to buy the F/A‐18, Dassault is adamant that the Avion de Combat Marine (ACM) ‐‐ Rafale's naval derivative ‐‐ will be chosen when it becomes available in 1996.
What the French Navy will do to plug the three‐year gap between the end of the F‐8E(FN) Crusader's life and the arrival of ACM is of great concern to the company.
Dassault is hoping that the French Government will decide to award it a contract to perform the minimum modifications necessary on the F‐8, pending the arrival of ACM, rather than buy or lease F/A‐18s.
The Alpha Jet Marine, a proposed navalised version of the Franco‐German trainer, has been given a boost by a growing need on the part of the navy to replace its Fouga Magister aircraft, used to train pilots for carrier operations.
The French MoD has issued a specification for a replacement aircraft, fully met by the Alpha Jet Marine, Dassault believes. The requirement, which could result in a contract award in the early 1990s, is for 40‐50 aircraft. A picture and details of the aircraft can be seen below.
In addition to efforts to entice Belgium to join the Rafale programme, Norway is also showing increased interest.
It wants a single type of aircraft to replace its F‐5s and F‐16s and has dismissed the European Fighter Aircraft as too heavy and expensive, according to Dassault company officials.
The USA and France cannot become involved in a co‐operative fighter development except in the area of subsystems, Dassault said. The Snecma M88 powerplant is already launched and Rafale is designed exclusively around the engine, ruling out any Franco‐US co‐operation until the generation of fighters after Rafale and Hornet 2000.
Dassault did confirm, however, that the company has had discussions with US industry on a derivative fighter for the future needs of both countries' armed forces.
Despite the success of the F‐16 and lately the MiG‐29 in world markets, Dassault is not discouraged about prospects for the Mirage 2000. The company has seen a swing towards dual‐sourcing for combat aircraft ‐‐ Jordan and India are notable examples, with Mirage 2000/Tornado IDS and Mirage 2000/MiG‐29 respectively ‐‐ and believes it can carry on taking advantage of the trend.
Following the launch of the ATR‐AMD Petrel 42/72 (JDW 10 September), a joint development between Aerospatiale/Aeritalia and Dassault to equip the ATR 42/72 with the weapons system on the Atlantique 2, Dassault said that diversification away from the pure combat aircraft market could not be ruled out.


@ indranilroy, An excellent Point. If you look at what Boeing has suggested for the Advanced/International Super Hornet, it prepares them to do a lot of work with advanced future jets. The cockpit they are presenting is most likely going to form a basis for their future bids if it hasn't already given they submitted to the USAF RFI's around 2009-10 for the F-22 replacement in addition to submitting to the FA-XX RFI's a year or so later. Also remember the AFRL project to advance the 5th generation mission systems including those on the F-22 and F-35 (both lockheed products) is being led by Boeing so it is entirely possible that Boeing does the Mission system overhaul on the F-35 during MLU stage where such advanced concepts learnt through the development of the advanced super hornet could contribute. Weapons pods, better RCS reducing coatings and things like CFT's in order to reduce or completely do away with EFT's is a good start leading up to the AMCA.

Regarding your point on the F-22, as I have mentioned many times it was an aberration. It was specifically tasked with taking out advanced soviet aircraft over european skies. If you look at the industry an unprecedented 1.2 Billion was spent by the industry (matched by the US government) and that led to all sorts of alliances. The only way Lockheed could spend 600+ million on their own technology development efforts (and prototyping) was if they hedged the risk through partners. So Lockheed reached out to Boeing and General Dynamics. Similarly McDonnell Douglas headged its 600+ million dollar investment by involving Northrop into their team. 1.2 billion was justified because the industry was expecting a total production run of close to 700 aircraft spread over 2 versions. In the end because these deals were struck for that volume of business, you count really do away with contracts to justify production efficiencies for a 200 odd fighter run (later reduced to 180 odd). The F-22 was always produced in a very inefficient way with Boeing and Lockheed operating two different factories for their work-share. Ideally it should have been built like the F-117, or the SR-71 where the Skunk works or Lockheed did all the production and assembly as the volume was not large enough to spread the work (and with it the risk). So from that point of view, the F-22 if retained as an insurance policy post-cold war and post peace dividend was always going to be expensive to procure because the industry had bid for and designed itself around a very larger order/production run. But given the investments already made into the program, a larger procurement of a few aircraft as an insurance policy was well worth it and they could move on to the F-X in the post 2030 period given that the Russians and the Chinese (2 peer threats) would find it hard to match the maturity of the F-22 in the numbers before mid to late 2020s, and the fact that they would have close to 1200-1500 JSF's by the time the first F-22A's reach 8K airframe hours.
Last edited by brar_w on 02 Jan 2015 05:14, edited 3 times in total.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Karan M » 02 Jan 2015 04:23

Indranil, Hmmm my thinking is AMCA was high end, LCA Mk3 low end w/limited stealth. More strike w/PGMs & utility rather than door kicker. But point taken about competing for the same pie.

One thing I'd want with your stealth version of LCA Mk2 = Mk3 is more fuel. Thats about the only issue with the JF-17/LCA/Gripen class platforms. They rely on support assets (IFR) too much. In our context, not an issue so much with TSP but with PLAAF it should help to some degree.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Indranil » 02 Jan 2015 05:23

IMHO, the long bombing runs should be left to the MKIs/FGFA and AMCA. LCAs could do it if required, but their prime responsibility should be to become tightly-integrated agile point defence fighters with lethal weapons. They should be cheap and numerous and signify our innermost circle of defence. Enemy fighters should be scared to come anywhere near the centres defended by LCAs.

Also, as I have expressed earlier, for ordering and producing LCAs, we should go the Russian way. We should order LCAs not Mk1s, Mk2s, or Mk3s. Get a full-fledged assembly line going at 16-fighters a year for Mk1 ASAP. Whenever Mk2 is production-ready, switch to Mk2 and so on. When Mk1s near end of life, just replace them with whatever the production line is currently churning out. This will keep the production costs low, morales of engineers and researchers high, and maintain the squadron-strength of IAF up with up-to-date fighters. Just my thoughts.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Karan M » 02 Jan 2015 05:29

I want extra fuel as its not a question of long bombing runs but persistence and flexibility. 1971/1965 air accounts are full of desperate pilots getting their aircraft back on fumes or having to cut off combat because fuel ran low. We really need to address that. IMHO, point defense also is limiting- i mean, we cant constantly keep fighters up for point defense alone. We need them for multi roles. If Bison can go for escort, we need our LCAs to do more and more. Of course, we cant have them cost as much as our AMCAs.
Also problem with not going MK wise is IAF logistics. IAF would want max aircraft to be of one type.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Karan M » 02 Jan 2015 05:30

Also, why dont you do a wrietup on the aerodynamics of the LCA? Where you are unsure mark it as such. At least it would serve as huge FAQ versus teh "feelings type" rubbish discussions we tend to engage in on a cyclical basis, having the same claims and same rebuttals.
Rest of us can add on other aspects etc.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Indranil » 02 Jan 2015 08:19

I will certainly take you and a few others up on that. It has been on my bucket list for far too long. But it has to wait till something due this May.

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_28932 » 02 Jan 2015 08:37

indranilroy wrote:
Dave sahab, I don’t understand what part of the underperformance on Mk1 you don’t understand.
1. The choice of the wing is a deliberate design choice. I don’t know why AVM Matheswaran is bringing up the canard issue now. Where was he (and the IAF) when ADA was studying canard layouts for the LCA? By the way, ADA studied various wind tunnel models (including the canard and the conventional tailplane) and found that LCA does not need an extra tailplane or a close-coupled canard. Instead the wing design is blended in a way to allow the trailing edge to work as a tailplane. Please find the studies of the F-16XL wing which is based on the same wing design. It did better than the F-16 with a tail plane. A case for a close-coupled canrd can be immediately shot down too. The wing does extremely well till 35 degrees AoA. The plane would have sufficient STR at 28 degrees AoA!


Dear sir,

I feel honored to be replied by a poster like you.

On the topic:

Tejas was our first attempt of making Plane after Marut. We started a huge R & D without much base line. We assumed a lots of thing in absence of experience and lack of DATA availability. Now Tejas is fine and flying. At this point of time we need to ask some simple questions. Whether Aircraft performs as design and whether it performs well with its counter parts such as Grippen, M2k etc. If answer is yes than it is ok and if answer is no than we need to ask ourselves some question such as what are the factors which hinders the performance of the aircraft? So far on performance front, it seems to be under-performing on some parameter such as Climb rate, Turn rate, Speed etc against design parameter as well as compare to its counterparts. Issue identified as we know are drag and heavy weight.

If this is the problem, we should ask ourselves that what we need to do to improve performance. Some of the issues discussed in public domain are 1) Weight reduction, 2) Wing redesign 3) Air intake redesign 4) Canard etc.

Yes, Tejas was designed keeping in mind the F-16XL type design of large wing with very high fuel efficiency. We attempted that. Now the performance is right in front of us. we require improvement. Has that wing redesign has delivered what we had expected from that design? Each design has its plus and minus. Here we need to ask whether the design performs as expected and whether the penalty paid for that design is worth paying compromising other parameter Such as STR?

After all we need to compromise somewhere. If this wing design has failed to deliver what is expected from it and on the contrary has a penalty on other parameter than that becomes a case of reconsideration of design parameter according to me. If heavy Grippen and M2K can fly fast and turn sharper than Tejas should also do that.

Yes, You are right. We can wait and see till plane hits 8 g and AOA reaches 28*. With opened envelope, if we can get the desired performance, it is ok else we should rethink over that. In my opinion we have the ability to make even MK1 a much better aircraft than what it is today provided we do not hide the problem and willing to work on shortfall.

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Re: LCA News and Discussions, 22-Oct-2013

Postby srai » 02 Jan 2015 08:56

indranilroy wrote:IMHO, the long bombing runs should be left to the MKIs/FGFA and AMCA. LCAs could do it if required, but their prime responsibility should be to become tightly-integrated agile point defence fighters with lethal weapons. They should be cheap and numerous and signify our innermost circle of defence. Enemy fighters should be scared to come anywhere near the centres defended by LCAs.

Also, as I have expressed earlier, for ordering and producing LCAs, we should go the Russian way. We should order LCAs not Mk1s, Mk2s, or Mk3s. Get a full-fledged assembly line going at 16-fighters a year for Mk1 ASAP. Whenever Mk2 is production-ready, switch to Mk2 and so on. When Mk1s near end of life, just replace them with whatever the production line is currently churning out. This will keep the production costs low, morales of engineers and researchers high, and maintain the squadron-strength of IAF up with up-to-date fighters. Just my thoughts.


Good points!

I read an article long time ago about F-16 vs MiG-29. One of the conclusions was that a heavily loaded F-16 in an offensive counter-air mode would be no match for lightly loaded MiG-29s in defensive point air configuration around their airbases.

As far as your point on full-fledge assembly line, that's what every country did to build their aerospace industries initially.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Yagnasri » 02 Jan 2015 09:05

My mango man thinking is production level issues also needed to be addressed ASAP. The reported private participation may be a game changer here. From what I gather there is a huge scope for LCA type light AC from the nations which are looking for a cheaper option to replace their Mig21 type ACs. Hence having a 40-60 AC manufacturing capacity may become a viable option if proper marketting etc is done. GE eng may be a problem for exports, but I am sure Khan will be willing to work with us to export this AC to its munnas at least. We ourselves need some good numbers so that LCA can take care most of the work in the west leaving other frontline ACs for North in a possible two front war.

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Re: LCA News and Discussions, 22-Oct-2013

Postby brar_w » 02 Jan 2015 09:11

All production lines are run in a way where a basic variant is created, sent into production (i.e. the line activates) and as new variants are cleared post testing, or post Critical design review they take over the production line.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Indranil » 02 Jan 2015 09:33

Vipul Dave wrote:Dear sir,

I feel honored to be replied by a poster like you.

On the topic:

Tejas was our first attempt of making Plane after Marut. We started a huge R & D without much base line. We assumed a lots of thing in absence of experience and lack of DATA availability. Now Tejas is fine and flying. At this point of time we need to ask some simple questions. Whether Aircraft performs as design and whether it performs well with its counter parts such as Grippen, M2k etc. If answer is yes than it is ok and if answer is no than we need to ask ourselves some question such as what are the factors which hinders the performance of the aircraft? So far on performance front, it seems to be under-performing on some parameter such as Climb rate, Turn rate, Speed etc against design parameter as well as compare to its counterparts. Issue identified as we know are drag and heavy weight.

If this is the problem, we should ask ourselves that what we need to do to improve performance. Some of the issues discussed in public domain are 1) Weight reduction, 2) Wing redesign 3) Air intake redesign 4) Canard etc.

Yes, Tejas was designed keeping in mind the F-16XL type design of large wing with very high fuel efficiency. We attempted that. Now the performance is right in front of us. we require improvement. Has that wing redesign has delivered what we had expected from that design? Each design has its plus and minus. Here we need to ask whether the design performs as expected and whether the penalty paid for that design is worth paying compromising other parameter Such as STR?

After all we need to compromise somewhere. If this wing design has failed to deliver what is expected from it and on the contrary has a penalty on other parameter than that becomes a case of reconsideration of design parameter according to me. If heavy Grippen and M2K can fly fast and turn sharper than Tejas should also do that.

Yes, You are right. We can wait and see till plane hits 8 g and AOA reaches 28*. With opened envelope, if we can get the desired performance, it is ok else we should rethink over that. In my opinion we have the ability to make even MK1 a much better aircraft than what it is today provided we do not hide the problem and willing to work on shortfall.

No honour, wonour yaar! We are all understanding this together.

To answer your questions, the problem is certainly not with the wings. It does fantastically till 35 deg AoA. And trust me with the configuration of LCA, at 28 degrees itself it will start kicking some serious butt. The problem is elsewhere, some of which you have pointed out. They are working on it.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Viv S » 02 Jan 2015 09:34

indranilroy wrote:Image


Could you share a source for this? Single vertical tail seems at odds with an LO airframe.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Indranil » 02 Jan 2015 10:11

Click here.

Just search for KFX-E. Lot of information out there. It was KAI's suggestion to mitigate risk by using components from the FA-50. It was shown in ADEX 2013.
Image

Of course, the canted tail version also exists.
Image

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Re: LCA News and Discussions, 22-Oct-2013

Postby brar_w » 02 Jan 2015 10:21

Viv S wrote:
indranilroy wrote:Image


Could you share a source for this? Single vertical tail seems at odds with an LO airframe.


It all depends what the requirements are. Before the USAF changed the VLO requirements for the ATF in the mid-1980's during the DEMVAL phase (greater emphasis on RCS reduction) General Dynamics that was a very major player at the time given its F-16 product had this as a design:

Image

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Re: LCA News and Discussions, 22-Oct-2013

Postby srin » 02 Jan 2015 11:40

I'm not sure if light aircraft (like LCA) can have big enough internal bays without increasing the empty weight. An air superiority loadout that I presume would be 4 BVRs and 2 heat seekers. I just don't see all that fitting into internal bays under fuselage and adjacent to the wings (like F-15 SE).

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Re: LCA News and Discussions, 22-Oct-2013

Postby Philip » 02 Jan 2015 12:39

I think that 2 BVRs and 2 SRAAMs,or 4 SRAAMs plus a cannon carried internally in fuselage/wing bays would suffice for stealth profile/point defence missions,since heavier aircraft would also be operating in conjunction.The LCAs would have to deal with those that escaped the Flankers and MIG-29s.If a stealth/reduced RCS version of the LCA is developed starting right now as the definitive MK-2 version,which in any case requires some extensive redesign,it would enhance the relevance of the LCA for the next 2+ decades.It would also give India a lead in developing a light-weight affordable stealth aircraft,with only the Gripen as a competitor.The configuration of the Korean,Japanese fighters still haven't been finalized as of now and unlike the LCA,which has its Mk-1 flying would take much more time to enter series production. There would be several middle-sized NAM nations,old friends whom India could offer the aircraft to. Extra MK-1s could be ordered in the interim if Mk-2 development stretches beyond 2020. This could partially plug the gap in numbers of retiring MIG-21s.

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Re: LCA News and Discussions, 22-Oct-2013

Postby shiv » 02 Jan 2015 14:05

Shonu wrote:shiv ji, would you not also want to test the structural strength of the landing gear due to the stress of essentially being pulled in two directions ? I was under the impression that this was the main thing that they tested for.

Sorry - I don't know what you mean by the landing gear being pulled in two directions. The landing gear has to bang down on the deck harder than in normal aircraft, but after that I can't think why the gear should be pulled in two directions. Can you explain what you mean?

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_28932 » 02 Jan 2015 15:09

rohitvats wrote:
Karan M wrote:I just let this discussion slide after some of the fudged up figures being posted non stop in the previous pages, to run down a program, truth and accuracy be darned but kudos to RV and vina for getting some data into the discussion.


Actually, most of the credit goes to Indranil's and Vipul Dave.

<SNIP>

So, if STR is not a key decider in todays scenario, why is the IAF pushing for it? A) Because they can, since it was part of the prior ASR as ambitious as that was and B) STR may matter in that one scenario where a LCA is without missiles & its guns, guns alone. As rare as this scenario is (think of a Su-30 w/10-12 AAMS f.e.), the IAF still trains for it (including Su-30 pilots).

Even so - check this out; https://www.youtube.com/watch?v=nWG2PkwKiaQ

The only solution to knocking these down is to use a DIRCM. Only the PAK-FA and JSF are to have these per reports. Flares wont work as these are IIR seekers with image discrimination capability. In short, this STR business is just a bunch of hokum.


With respect to bold part, that is not the line of argument I'd want to take. As it is, it is a very extreme stand. Something like F-4 and AAM and no requirement for guns. We know where it all went.

The fact that IAF - and all the major air forces - train and prepare for 'Dog-Fight' scenarios is testimony to importance of parameter like STR. If memory serves me right, IAF teaches 1-vs-2 to Mig-29 pilots. The one a/c which actually holds forte in STR as well as was first to have HMCS advantage.

However, as you've pointed out with the Python example, there are solution(s) which help to compensate on this aspect. And IIRC, Python/Derby is being tried for LCA Mk-1.


Actual LCA with limited envelope opened in Aero India 2013 has displayed an excellent 20 second High speed vertical loop timing. Since it has done 7+ G (As per saurav Jha) and AOA is reaching 26* now, we should expect a better timing in horizontal loop also. If It reaches 22 second, it should be sufficient in My opinion and should be acceptable. We can improve further to 20 second timing in future by further opening the envelop and some other measures such as Slashing Weight and redesigning of wings, improving the power of engine etc.

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_28932 » 02 Jan 2015 16:02

akshat.kashyap wrote:
They gave the FOC date(Dec. 2014) based on delivery date promised by the vendor, if vendor couldn't deliver on time, how can we blame project management?


When you know that Nose cone has an issue. Why did you not order till last minute and ordered that at a point of time when any little delay in delivery resulted into Delay in FOC. This is called poor project management. The Issue was known to them since 2009 if I am wrong. FOC is delayed for a problem which was known to us 5 years ago. Other issue is Gun integration. Did you know that Gun is required to be integrated since you design tejas? Why don't you try the integration in 2004 or 2005?
Why did you wake up only after IOC 2? Even Russian would have done it for some dollar. Same is for fuel refueling probe and so on. If you are a good project manager, you should know where and when the particular activity be started. That doesn't require a very high intellect. You just need to be trained in Project management.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Shreeman » 02 Jan 2015 16:10

Fly faster, turn higher, do the cobra, outdo the itr of this, and the str of that while AoA the AoA ias 67 degrees and pilots are ejecting. This is not a pure though /intellekchual ingratiation eggsercise any more.

Between 1971 and 2015 -- dogfights have been at a level way way below bird hits, flame outs, pilot errors, engine malfunctions, structural failures, cows on the runway.

There are not going to be more dog fights in the future. This is accepted. So churning examples out to users, and doing warranty repairs to keep product functional is what is needed. Stop driving the ladas in hope a dog fight will materialise tomorrow.

This ITR/STR value debate serves zilch function. No official figues exist. Given the NSA's letter soon the names of the aircraft will be above disclosure. The he said 7g she flew 8g we need 9g is all just waiting until the next test pilot tells his story and then we start from zero again.

Why not visit the hunters of kalaikonda one more time? Probably cow sheds there now. There is no alternative to building on time with acceptable level of performance. LCA has been at acceptable level for five or more years. Its being dragged along to keep the other negotiations sane. Wjhen this big contract is signed, and distribution plan of phoreign mall becomes known the LCAs will go to the Sulirs and the Jharkhands where no Rafail driver will send his kids to school.

And that is a good thing. New bases (not renaming of IG airbase with 4x4 feet apron increase to LBS base), new units, new environment -- rather than sticking LCAs in a closet in the current culture of 30s or 2000s. The doctrine must also develop like the platform and not be copied or laughed at by the french reading or russian writing staff.

None of this has anything to do with project management. Vendors crap out for good reasons all the time. You still ship what you have. A recall to upgrade on vikramaditya (CIWS) to swapping radome on LCA. All part of normal game.

They may bring 4 SPs to AA2015 and claim all this is past now. It was past and meaningless in 2010. Scratch the surface on the tarmak, is it the rafail pocket lining that is having an impact here? What really is the vertical takeaway? Keep LCA low or we wont be retiring to australia -- because it will crash or because pockets not lined thick.

If asked, why arent you pushing harder to induct it today from the bottom what does a test pilot say?

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_28932 » 02 Jan 2015 16:15

indranilroy wrote:
Vipul Dave wrote:Dear sir,

I feel honored to be replied by a poster like you.

On the topic:

Tejas was our first attempt of making Plane after Marut. We started a huge R & D without much base line. We assumed a lots of thing in absence of experience and lack of DATA availability. Now Tejas is fine and flying. At this point of time we need to ask some simple questions. Whether Aircraft performs as design and whether it performs well with its counter parts such as Grippen, M2k etc. If answer is yes than it is ok and if answer is no than we need to ask ourselves some question such as what are the factors which hinders the performance of the aircraft? So far on performance front, it seems to be under-performing on some parameter such as Climb rate, Turn rate, Speed etc against design parameter as well as compare to its counterparts. Issue identified as we know are drag and heavy weight.

If this is the problem, we should ask ourselves that what we need to do to improve performance. Some of the issues discussed in public domain are 1) Weight reduction, 2) Wing redesign 3) Air intake redesign 4) Canard etc.

Yes, Tejas was designed keeping in mind the F-16XL type design of large wing with very high fuel efficiency. We attempted that. Now the performance is right in front of us. we require improvement. Has that wing redesign has delivered what we had expected from that design? Each design has its plus and minus. Here we need to ask whether the design performs as expected and whether the penalty paid for that design is worth paying compromising other parameter Such as STR?

After all we need to compromise somewhere. If this wing design has failed to deliver what is expected from it and on the contrary has a penalty on other parameter than that becomes a case of reconsideration of design parameter according to me. If heavy Grippen and M2K can fly fast and turn sharper than Tejas should also do that.

Yes, You are right. We can wait and see till plane hits 8 g and AOA reaches 28*. With opened envelope, if we can get the desired performance, it is ok else we should rethink over that. In my opinion we have the ability to make even MK1 a much better aircraft than what it is today provided we do not hide the problem and willing to work on shortfall.

No honour, wonour yaar! We are all understanding this together.

To answer your questions, the problem is certainly not with the wings. It does fantastically till 35 deg AoA. And trust me with the configuration of LCA, at 28 degrees itself it will start kicking some serious butt. The problem is elsewhere, some of which you have pointed out. They are working on it.


Thank You sir.

It is nice to know that it will perform very well at 28* AOA.

I got the impression of wings not working well from one recent article which states that

"But this project that should be making Indians proud and enhance the reputation of our scientists’ world wide is coming under a harsh scrutiny now. Here are some of the problems plaguing it : The composite wings need redesigning. There are some unanticipated complexities faced in structural design too."

http://www.recreationalflying.com/threa ... ay.128696/

If wings are working well, it is great. We shall have to work remainig areas only.

Looking to the F 16 XL like wing design, It must have a great fuel efficiency because of great gliding ability.

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Re: LCA News and Discussions, 22-Oct-2013

Postby deejay » 02 Jan 2015 16:54

Shreeman wrote:Fly faster, turn higher, do the cobra, outdo the itr of this, and the str of that while AoA the AoA ias 67 degrees and pilots are ejecting. This is not a pure though /intellekchual ingratiation eggsercise any more.

Between 1971 and 2015 -- dogfights have been at a level way way below bird hits, flame outs, pilot errors, engine malfunctions, structural failures, cows on the runway.

There are not going to be more dog fights in the future. This is accepted. So churning examples out to users, and doing warranty repairs to keep product functional is what is needed. Stop driving the ladas in hope a dog fight will materialise tomorrow.

This ITR/STR value debate serves zilch function. No official figues exist. Given the NSA's letter soon the names of the aircraft will be above disclosure. The he said 7g she flew 8g we need 9g is all just waiting until the next test pilot tells his story and then we start from zero again.

Why not visit the hunters of kalaikonda one more time? Probably cow sheds there now. There is no alternative to building on time with acceptable level of performance. LCA has been at acceptable level for five or more years. Its being dragged along to keep the other negotiations sane. Wjhen this big contract is signed, and distribution plan of phoreign mall becomes known the LCAs will go to the Sulirs and the Jharkhands where no Rafail driver will send his kids to school.

And that is a good thing. New bases (not renaming of IG airbase with 4x4 feet apron increase to LBS base), new units, new environment -- rather than sticking LCAs in a closet in the current culture of 30s or 2000s. The doctrine must also develop like the platform and not be copied or laughed at by the french reading or russian writing staff.

None of this has anything to do with project management. Vendors crap out for good reasons all the time. You still ship what you have. A recall to upgrade on vikramaditya (CIWS) to swapping radome on LCA. All part of normal game.

They may bring 4 SPs to AA2015 and claim all this is past now. It was past and meaningless in 2010. Scratch the surface on the tarmak, is it the rafail pocket lining that is having an impact here? What really is the vertical takeaway? Keep LCA low or we wont be retiring to australia -- because it will crash or because pockets not lined thick.

If asked, why arent you pushing harder to induct it today from the bottom what does a test pilot say?


---whole lot of wishful thinking---

Owww! you hit the nail on the head and hard. A few minor wrong turns but mostly agreed. The bold part made me :mrgreen:

The LCA is more than ready and I will bet my last penny to the fighter jock who uses +9G of the maneuver envelope as a regular practice. Hell! will be happy if one tries +7G stunts with those 'G' suits and all. Mostly will get in to those regimes inadvertently or as some Air Show display routine.

By the time IAF gets to developing the Tactics using the outer envelop of the LCA the Mark 2's should be there. Get that damned Indian nose cone, get that farther than the farthest Galaxy, FOC done now. Make sure to eff up the Rafail deal and bury it in the Challenger Deep.

Now, we should have saved 20 Billion dollar plus in the kitty. 6th gen Indian aircraft anyone? Or did I here a desi Strategic Bomber on the wish list? Wait, the desi Star Wars programme needs to start.

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Re: LCA News and Discussions, 22-Oct-2013

Postby vina » 02 Jan 2015 17:06

Looking to the F 16 XL like wing design, It must have a great fuel efficiency because of great gliding ability.

There we go. More English. Now.. "Looking" instead of "Feeling" . Why this is the first time that I think I will ever hear anyone say that that a low aspect ratio fighter wing has great "fuel efficiency" because it has "great gliding ability" . That is something like saying that Tun Tun Mausi will have great mobility because she "looks" rotund! :shock: :shock:

Anyone who knows anything about these things that the most efficient wings for "gliding" (ie great fuel efficiency :roll: ) is a very high aspect ratio wing like that are found in well "gliders".

Guys.. (Victor babu, Vipul babu et al, ), atleast do some basic reading /google up if you need to before posting on this thread. It gets filled up very quickly with "feeling", "looking" and similar stuff and zero thinking and analyzing and reality per laws of physics, or worse, it gets kicked down one level down to "XXXX said this", " Some committee needs to be formed do something with LCA" . Let us keep this focused on facts, engineering and reality and let us keep "looking", "feeling" and make believe firmly in the realm of dance, drama, arts, social studies and political "science" .

For instance, if I were to say that the LCA wing will have really poor gliding characteristics (which is true) it will set off a huge amount of ill informed R&D (Rhona & Dhona) and also shlong is long measuring contests of which aircrafts wing has a better "gliding" characteristics. Such is life.

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Re: LCA News and Discussions, 22-Oct-2013

Postby ritesh » 02 Jan 2015 20:48

Vipul Dave wrote:Now Tejas is fine and flying. At this point of time we need to ask some simple questions. Whether Aircraft performs as design and whether it performs well with its counter parts such as Grippen, M2k etc.

Q is why should we compare Tejas to Grippen / M2k????
Neither are with our adversaries right now and will never be their choice, as pakis cannot afford it and chinese cannot accesss it.
Tejas needs to be evaluated against JF17 and Su27 & its copies with PLAAF.
That will be right comparo for it & how it overcomes them should be our focus
Last edited by ritesh on 02 Jan 2015 21:15, edited 1 time in total.

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Re: LCA News and Discussions, 22-Oct-2013

Postby brar_w » 02 Jan 2015 20:59

^^ This! more importantly how does the early versions of the LCA perform against the expected performance of the jets as opposed to the status quo.

Comparison with Gripen is only important for export, and I don't think that exporting the Tejas should be top priority at this moment. Even from an export point of view, get the thing in combat service in the right numbers and it would send a very strong message to potential customers. The best way to inspire confidence in a product is to buy it yourself in large amounts.

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_28788 » 02 Jan 2015 22:01

ritesh wrote:
Vipul Dave wrote:Now Tejas is fine and flying. At this point of time we need to ask some simple questions. Whether Aircraft performs as design and whether it performs well with its counter parts such as Grippen, M2k etc.

Q is why should we compare Tejas to Grippen / M2k????
Neither are with our adversaries right now and will never be their choice, as pakis cannot afford it and chinese cannot accesss it.
Tejas needs to be evaluated against JF17 and Su27 & its copies with PLAAF.
That will be right comparo for it & how it overcomes them should be our focus


Exactly. That would make more sense! Except that this comparison should also have been done in the long hitory of this LCA thread but as we keep beating the capability question, it might be a good idea to reframe the debate in terms of Indian defense reqd. in context of the pak-chn threat.

At a theatre level PLAAF deploying J-10s, SU-30MKKs and older SU-27s, etc with chini AEW&C vis-a-vis India deploying LCAs with a mix of SU30-MKIs with Phalcon and aerial refuelling support. Thats is the scenario in which LCA should make sense & it pretty much does- but someone could do service by filling in facts & details into the context.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Prasad » 03 Jan 2015 00:18

Might be old hat but why was the LCA not taken in after IOC? Why the need for FOC when even the euro fighter was inducted at does production level? Foc, ground attack, lgb capability were all done later. Same with meteor integration.

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Re: LCA News and Discussions, 22-Oct-2013

Postby brar_w » 03 Jan 2015 00:23

The Typhoon won't reach its multi-role goal until perhaps the second half of 2018, a full 14 years after it declared operational status. Similarly the Rafale was in active/front line service and was actually participating in warfare activities over Afghanistan without having a basic targeting pod giving it the ability to self-designate targets and the OEM/developers called it an Omni Role fighter. The point being that integration, store clearances and enhancements take time and there is really no good reason to not send the weapons system out to front-line units where it can start contributing in its own way and giving you feedback from the mainstream combat coded units.

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Re: LCA News and Discussions, 22-Oct-2013

Postby rohitvats » 03 Jan 2015 00:23

Prasad wrote:Might be old hat but why was the LCA not taken in after IOC? Why the need for FOC when even the euro fighter was inducted at does production level? Foc, ground attack, lgb capability were all done later. Same with meteor integration.


There is a standing order for 20 LCA @ IOC level. Of which first two will come, hopefully, by March 2015.

So, what's the angst against?

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Re: LCA News and Discussions, 22-Oct-2013

Postby Wickberg » 03 Jan 2015 01:18

ritesh wrote:
Vipul Dave wrote:Now Tejas is fine and flying. At this point of time we need to ask some simple questions. Whether Aircraft performs as design and whether it performs well with its counter parts such as Grippen, M2k etc.

Q is why should we compare Tejas to Grippen / M2k????
Neither are with our adversaries right now and will never be their choice, as pakis cannot afford it and chinese cannot accesss it.
Tejas needs to be evaluated against JF17 and Su27 & its copies with PLAAF.
That will be right comparo for it & how it overcomes them should be our focus


It might have something to do with the similarities. Two lightweight projects started at the same time (early 80s), single engined- even shares the same engine (kind of), none of them belonging to any of the classic super powers (USSR/USA) nor a European conglemorate. Considering all this it´s not hard to understand why they are beeing compared. The fact that the LCA and Gripen has gone totally different ways since the projects was started has offcourse changed this. But I remember just a few years ago most people on this board were still comparing the LCA to the Gripen and arguing how much superior the LCA was (is) and how it would dominate the export market, not to mention any fighter the Pakis or Chinese would show up. How times can change in a few years...

NRao
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Re: LCA News and Discussions, 22-Oct-2013

Postby NRao » 03 Jan 2015 01:22

Might be old hat but why was the LCA not taken in after IOC? Why the need for FOC when even the euro fighter was inducted at does production level? Foc, ground attack, lgb capability were all done later. Same with meteor integration.


Good question.

A better one may be what did the IAF do when they got other planes. Did the Mirage 2000, as an example, come full blown or have issues? MiG-29 we know what happened. The Su-30 too we know what happened. Other MiGs/Jags/etc.

Indranil
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Re: LCA News and Discussions, 22-Oct-2013

Postby Indranil » 03 Jan 2015 02:22

brar_w wrote:The Typhoon won't reach its multi-role goal until perhaps the second half of 2018, a full 14 years after it declared operational status. Similarly the Rafale was in active/front line service and was actually participating in warfare activities over Afghanistan without having a basic targeting pod giving it the ability to self-designate targets and the OEM/developers called it an Omni Role fighter. The point being that integration, store clearances and enhancements take time and there is really no good reason to not send the weapons system out to front-line units where it can start contributing in its own way and giving you feedback from the mainstream combat coded units.

My pet peeve for a very long time

Karan M
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Re: LCA News and Discussions, 22-Oct-2013

Postby Karan M » 03 Jan 2015 02:51

Wickberg wrote:It might have something to do with the similarities. Two lightweight projects started at the same time (early 80s), single engined- even shares the same engine (kind of), none of them belonging to any of the classic super powers (USSR/USA) nor a European conglemorate. Considering all this it´s not hard to understand why they are beeing compared. The fact that the LCA and Gripen has gone totally different ways since the projects was started has offcourse changed this. But I remember just a few years ago most people on this board were still comparing the LCA to the Gripen and arguing how much superior the LCA was (is) and how it would dominate the export market, not to mention any fighter the Pakis or Chinese would show up. How times can change in a few years...


Lets catch up a decade from now and see if your lot even makes fighters..


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