You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
HAL Tejas Jet Fighter
- Thread starter Delbert
- Start date
THE ABOVE LINK IS A MUST READ FOR ANYONE TO UNDERSTAND THE TIMELINES, MAGNITUDE OF THE TECH CHALLENGES FACED AND WHAT WAS ACHIEVED IN TEJAS PROGRAM
Most of the misconception regarding tejas can be cleared by the through read of the above article by AIR MARSHAL ASD WOOLLEN WHO WAS THE HALCHAIRMAN DURING THE CRITICAL PERIOD OF 1984 to 89 when the lca program was conceptualized.
(article from 2001)
continued in the next post.
Most of the misconception regarding tejas can be cleared by the through read of the above article by AIR MARSHAL ASD WOOLLEN WHO WAS THE HALCHAIRMAN DURING THE CRITICAL PERIOD OF 1984 to 89 when the lca program was conceptualized.
(article from 2001)
This story is incomplete. With the maiden, 20-minute flight of the first Technology Demonstrator of the Light Combat Aircraft on January 4, 2001, one could say it was halfway through. Even at this point of time, it is of enormous interest to nations in the far corners of the world. India has two priorities One, improve the quality of life of a third of its population. Two, keep inviolate its borders, shores and skies. The latter requires military might.
The geo- politics of the region (South Asia and surrounds) is of such a complexity that, despite good intentions of all, major conflicts have erupted; border skirmishes and cross- border terror-ism continue. In fact, right from Day 1 (August 15, 1947) India has faced a military threat; because of this, there is a compulsion to achieve self-reliance in design, development and production of weapon systems e.g. the LCA. It may be noted that some Asian countries, with great economic wealth and technical know why/know how, do not have such a compulsion. Further, success of the LCA program is a must for continuation and enhancement of India's aircraft industry. For these reasons, 33 R&D establishments; 60 major industries and 11 academic institutions participate in the program. Unfortunately, there has been a great deal of hype by the Defence Research and Development Organisation (DRDO) as to its capabilities, contemporariness and when it will enter service. This has led to, although not unwarranted, cynicism.
Background Information
An important recommendation of the Aeronautics Committee, which was accepted by Government in 1969, was that Hindustan Aeronautics Ltd (HAL) should design and develop an advanced technology fighter aircraft around a proven engine. Based on IAF 'air staff target' papers, HAL finally completed design studies for a Tactical Air support Aircraft in 1975 and it appeared that HAL would, after a lapse of twenty years, get down to developing a fighter. However, the selected ‘proven engine’ from abroad, could not be procured and the project fell through. HAL's design and development capability started to decline. Meanwhile, The IAF's requirement for an air superiority fighter (primary role) with air support/interdiction capability (secondary role) in the tactical battle area, continued.
The DRDO obtained feasibility studies from three leading aircraft companies (British, French and German). Use was made of these studies in presenting a case to Government for design and development of an LCA. In an unusual step, a Society was set up to over-see the LCA development program. At its apex is a 15-member General Body, whose president is the Defence Minister. The next rung is a 10-member Governing Body, whose Chairman is the SA to the Defence Minister and Secretary DRDO. The third rung is a 10-member Technical Committee, headed by the DG Aeronautical Development Agency (ADA); the latter post has been vacant ever since the first DG resigned in 1986. ADA manages the development program while HAL is the principal partner. The initial projection for completion of the program was totally erroneous and is largely attributable to lack of knowledge and experience. Projections were: first flight in 1990; production to commence in 1994.
Delay in commencement of Project Definition (PD) gave ADA time to marshal national resources (80 work centers spread over the country); to construct buildings, recruit personnel and create infra-structure; and to get a clearer perspective of the advanced technologies that could be indigenously developed and those that would need to be imported. The IAF's Air Staff Requirement, finalized in October 1985 is the base document for development. Requirements of flight performance, systems performance, reliability, maintainability criteria, stores carnage, etc. are spelt out. Concessions or a higher standard of requirements have to be mutually agreed upon by the IAF (customer) and ADA (constructor). Having a Society and Committees is, perhaps, the quickest way to bring about agreement.
continued in the next post.
continued
continued in the next post.
The Program
Project definition (PD) commenced in October 1987 and was completed in September I988. The consultant, chosen from four contenders, was Dassault Aviation, France. Engineers, connected with design and development of aircraft know how vital it is to get the 'definition' correct. From this flows detail de-sign, construction and eventually maintenance costs.
After examining the PD documents, the IAF felt that the risks were too high (likely shortfalls in performance, inordinate delay, Cost over-run, price escalations) to proceed further. A Review Committee was formed in May 1989. Experts from outside the aviation industry were included. The general view was that infrastructure, facilities and technology had advanced in most areas to undertake the project. As a precaution, Full Scale Engineering Development would proceed in two phases. Phase 1: design, construction and flight test of two Technology Demonstrator aircraft (TDI & 2); construction of a Structural Test Specimen; construction of two Prototype Vehicles (PVI &2); creation of infrastructure and test facilities. Phase 2: construction of three more PV '5, the last PV5, being a trainer; construction of a Fatigue Test Specimen; creation of facilities at various work centres. Cost of Phase I - Rs.2188 crores, of Phase II - Rs. 2,340 crores. Phase I commenced in 1990. However, due to a financial crunch, sanction was accorded in April 1993 and was marked by an upsurge in work. The critical path in this program has been the design, fabrication and testing of its fly-by-wire flight control system FCS). An electronic FCS is a must for an aircraft with relaxed static stability.
The FCS also provides the pilot 'care free handling'; flight limits cannot be exceeded, which at lower speeds on aircraft like the MiG-23/27 or Jaguar, results in the loss of the aircraft. The Aeronautical Development Establishment (ADE) is the nodal agency for development of the FCS. One reason for delay of the first flight could have been the unexpectedly large effort required for coding control laws into the FCS software, which were then checked out on Minibird and Ironbird test rigs at ADE and HAL, respectively. The control laws were developed with the aid of real time simulators at ADE and BAe, UK. As a point of interest, a second series of in-flight simulation tests of flight control software took place in July 1996 at Calspan USA on an F-16D VISTA (variable in-flight stability aircraft); 33 test flights were carried out. Another reason for delay was the sanction imposed after Pokhran II in May 1999. Scientists working at Lockheed Martin, USA were sent back; equipment, software and documents were impounded. Herculean efforts brought the FCS software to a standard where the FCS performed flawlessly over 50 hours of testing on TD 1 by pilots, resulting in the aircraft being cleared for flight in early 2001.
Space constraints prevent any meaningful description of materials, technology, facilities, processes developed for execution of the project. Military aviation enthusiasts may read a monograph on Aeronautical Technology that has attained maturity through DRDO efforts; much of this technology finds application in the LCA project. The monograph was brought out at Aero India 1998. The LCA is tailless with a double-sweep delta wing. Its wing span is 8.2 m, length 13.2 m, height 4.4 m. TOW clean 8.500 kg, MTOW 12500kg. It will be super-sonic at all altitudes, max speed of M 1.5 at the tropopause. Specific excess power and g-over load data has not been published. Maximum sustained rate of turn will be 17 deg per sec and maximum attainable 30 deg per sec. Funds have been sanctioned for a Naval LCA. PD and studies in critical technology areas have commenced. The aircraft will be powered by a Kaveri engine (more information follows) and is to operate from the Indian Navy's Air Defence Ship, under construction. Launch speed over a 12 deg ramp is 100 kts; recovery speed during a no flare deck landing, using arrester gear, is 120 kts. Take off mass 13 tonne, recovery mass 10 tonne. Most stringent requirements are that the airframe will be modified: nose droop to provide improved view during landing approach; wing leading edge vortexes (LEVCON) to increase lift during approach and strengthened undercarriage. Nose wheel steering will be powered for deck maneuverability.
During early flight development, the TD aircraft will be powered by a single GE F404 F2J3 engine (7,250 kg reheat thrust). The indigenous Kaveri engine, under development by the Gas Turbine Research Establishment (GTRE) is slated for installation in a PV aircraft. Over 7,000 hours of ground testing of the core engine (Kabini) and four prototype Kaveri engines, together with flights in a Tu-16 test-bed aircraft would have been completed. Engine components have been produced by several manufacturing units, including HAL, where the exclusive Cellular Manufacturing Facility (CNC machining) was established in November 1988. A concurrent engineering approach has been followed to provide engines early in the LCA's flight development. Salient engine features include the 3 stage fan; 6 stage HP compressor with variable geometry IGV, I and II stators; annular combustion chamber; cooled single stage HP and LP turbines; modulated after-burner; fully variable, convergent-divergent nozzle; length 3490 mm; max diameter 910 mm; dry thrust 52 kN; reheat thrust 81 kN; thrust weight ratio 7.8. The 'Achilles heel; in the successful development of the LCA, in the opinion of this author, is the Kaveri engine.
continued in the next post.
continued
Points of view
In the late eighties India's aircraft Industry was not as advanced as Sweden's; and yet India follows a more arduous design/development route for its LCA, compared to Sweden for its JAS-39 Gripen. The Gripen embodied a far higher percentage of foreign, off-the-shelf technology, including its RM-12 engine (improved GE F404). France (Dassault Aviation) built and exhaustively flew a demonstrator aircraft (Rafale-A) before embarking on construction of Rafale prototypes. Over 2,000 flights were completed by September 1994 when first Flight of a production Rafale was still 20 months away. At that point of time, Dassault Aviation had built or flown 93 prototypes, of which at least fifteen went into production after sixteen years elapsed from 'first-metal-cut' of the Rafale demonstrator to entry into service. Current plans for the LCA is ten years. And what of India's past record? Just a hand-ful of trainer aircraft designed and productionised. The story is similar for the Typhoon (earlier Eurofighter 2000). It was seventeen years from 'first-metal-cut' (EAP) to squadron entry in 2000. One more timeframe needs to be noted. It took Gripen six and a half years from first flight (prototype) to entry into squadron. For the LCA, four and a half years is the target! The quantum of test flying hours required to attain Initial Operational Clearance (IOC) is about 2000 hours; an impossible task in four and a half years. Concurrent production will shorten service entry time, but this will not enable the present target to be reached.
The LCA remains a high-risk project. All too often glitches occur in development of a fly-by-wire FCS. The Typhoon is an example; this, despite vast experimental work for over a decade by leading aircraft manufacturers in the UK and Germany (Jaguar, F-104, EAP). Engine development is the most complex of all activities. There are sure to be problems during flight development of the Kaveri, GTRE's first engine. Teething problems after service entry will occur; and major reliability improvements will be required in the first decade of its exploitation. Engines of the Russian fleet of fighters operated by the IAF (MiG-21 BIS, MiG-23BN/27M MiG-29) have this in-service history. Proceeding from this, four points emerge:
(a) India has its best designers, engineers, scientists, academicians working on and contributing to the project. They are devoted and tireless in their efforts to success-fully complete the project. They need support (not blind support) of the polity, defence services and bureaucrats. Public support will follow, provided there is honest transparency;
(b) Costs of the project will escalate. (Checks and balance are necessary, but let there be no inordinate delays, as have occurred in the past;
(c) The future of the aircraft industry, military and civil, depends on success of the LCA (and ALH, Saras, HJT-36) project; and,
(d) It is unlikely that the LCA will attain initial operational clearance (IOC) before 2010.When it is achieved, it will be an industrial success of magnificent proportion, and is sure to receive the acclaim it deserves.
A few words on the final operational clearance (FOC). The entire avionics and weapon systems are con-figured around three 1553 B data bus. Mission oriented computation/flight management is through a 32 hit computer. Information: from sensors (e.g. multi-mode radar, IRST, radar/laser/missile launch-warning receivers); from the inertial navigation System with embedded GPS; from targeting pod (FLIR, laser designator) are presented to the pilot on a head-up-display and head-down-displays. A helmet mounted target designator steers radar and missile seekers for early target acquisition (during a 'close-in' air-to-air engagement with a Vympel R-73 missile, currently the best dog-fight' missile in the world). Laser guided bombs and TV guided missiles, require a pilot to initially 'zero-in' the laser designator or missile-mounted TV camera, on the ground target. Considerable engineering effort and expertise is necessary to achieve avionics-weapon integration and to prove the integration by live trials. Success here means FOC. Depending on what is stated in the (updated) ASR, it could take two years and around 1,500 hours of flight testing to move from IOC to FOC.
There will be setbacks in the flight development phase. All major engineering projects suffer them. For instance, India's first two SLVs failed disastrously. The Prime Minister was present at the first launch at Sriharikota; so was this author. Disappointment was everywhere but no recrimination; only determination to get it right. Loss of a demonstrator aircraft or prototype could take place; lives could be lost, leading to questions/debate. Therefore, let the recent transparency in the program continue, even intensify; let it be honest, 2010 is not far, for a first' program of this magnitude and complexity.
·
NLCA completed 43 flights so far out of which 24 flights done during FY 14-15: HAL
·
Tejas so far completed 2871 flights out of which 364 were carried out during FY 14-15.
Former SA to PM Ashok Parthasarathi and Vice Adm. (retd) Raman Puri have explained what really happened to the LCA program in this extremely well written piece for The Hindu.
Ashok Parthasarathi and Raman Puri
The facts with regard to perceived cost and time overruns and performance shortfalls in perspective
There have been several articles in the press critical of projects of the Defence Research and Development Organisation (DRDO) in general, and specifically the programme relating to the Light Combat Aircraft (LCA), now named Tejas, and the Integrated Guided Missile Development Programme. Indeed, whenever a significant event that involves indigenous R&D, particularly defence-related, occurs, or a crucial decision is set to be taken, articles originating from within the defence “system,” or from vendors who see their business prospects threatened, appear. The real facts relating to the programme need to be put in context.
Performance shortfalls
The two issues on which the LCA project is criticised are cost and time overruns, and performance shortfalls. As regards the so-called time overruns, when the zero/go date for the project is taken as 1983, the critics fail to mention that what was sanctioned in 1983 was an ad hoc Rs.560 crore, pending full preparation of the Project Definition Document (PDD) — which is a fundamental step even to start the design and development process. The costs were to be finalised based on the PDD. This required the setting up of infrastructure in a hundred academic institutions and R&D laboratories and building up expertise to undertake the fundamental and application-oriented R&D required, and harnessing the design and engineering effort available largely in the public sector units for such a complex, state-of-the-art aircraft. The Aeronautical Development Agency (ADA) discussed with Air Headquarters the Air Staff Requirement (ASR). Air Headquarters had requirements added to what was originally to be a replacement for the MiG-21. As a result, the ASR that was finalised was practically that for a Mirage 2000. But in the public perception the LCA remained as a replacement for MiG 21.
It look seven years, till 1990, to formulate the PDD. Based on this the ADA, in a report to the Ministry of Defence in 1990, gave a time-frame of seven years to develop the LCA and projected a financial requirement of Rs.4,000 crore. This included the building of four prototypes also. There had been a 25-year gap since the only fighter aircraft ever indigenously designed, developed and manufactured, namely the HF-24 Marut, had entered squadron service. So the period of seven years to set up a more advanced R&D infrastructure and build up even the core personnel needed to develop the technologies that the LCA’s ASR and PDD called for, was modest.
“Go-ahead”
After consideration, including by special committees, the Indian Air Force and the government gave the real operational go-ahead only in late-1993. Even that “go-ahead” covered the development of only two Technology Demonstrator Aircraft (TDA) without weaponisation. The funding approved was only of Rs.2,000 crore — half the amount requested for full-scale development. The first TDA flew in 2001, eight years from the real operational ‘go’ date, despite much additional R&D work that had to be undertaken due to the U.S. sanctions imposed in 1998.
Comments appeared in the media in 2001 quoting IAF sources to the effect that what the ADA had achieved was just a flying machine that was yet to be weaponised. Considering the nature and scope of the approval accorded in 1993, what else was to be expected? Using the money sanctioned for two TDAs, the ADA built four. Full-scale development, for which another Rs.2,000-plus crore was finally sanctioned, thus started only in late-2001. Some 1,200 hours of flight testing was to be undertaken to secure Initial Operational Clearance (IOC) from the IAF.
At that point, apart from the weaponisation requirements the project had to undergo extensive redesign to accommodate an air-to-air missile chosen by the IAF, which was considerably heavier and longer than what had been specified till 2000. The IAF had again changed its mind. This necessitated the complete redesign of the wing structure, using only composite materials in order to keep the weight within limits. The period of this redesign was also utilised to upgrade the avionics, to a completely open architecture.
Consequently, in “generational terms” the LCA is a fourth generation-plus aircraft with full networking capabilities. This made it more than comparable to anything the IAF had, and possibly would have, even after it acquires the 126 Multi-Role Combat Aircraft (MRCA) now on tender, with first deliveries due eight years hence.
On the engine
It is true that the Kaveri engine for the LCA that the Gas Turbine Research Establishment (GTRE) of the DRDO has been developing for 12 years has not yet met its technical performance targets and requires redevelopment. So far the GE 404 engine from the U.S., which powers the F-16 fighter-bomber, has been used to power the LCA. The problems the GTRE has with the Kaveri are not unusual in a complex fighter aircraft engine project being undertaken for the first time. Moreover, the financial sanction of about Rs.320 crore given for engine development was possibly only to cover the Project Definition Phase and some high-risk technology development effort. We do not know of a first-of-type high-technology fighter aircraft engine being developed anywhere in less than a multi-billion dollar programme and a 20-year-plus development cycle. Even Snecma, the sole fighter aircraft engine manufacturer in France, despite decades of experience in developing and manufacturing engines for Mirage III, V and F-1, took about a decade and $2.2 billion to develop the M-88 engine for the Mirage 2000. The development of the Kaveri is unlikely to cross $1 billion.
The LCA with a GE 404 engine has done 800-plus hours of flight-testing. Even with that engine the performance has been not only vastly superior to that of even the recently upgraded MiG 21 BIS (the IAF is operating almost 400 of the series), but it has shown itself to be comparable in many critical parameters to the Mirage 2000. Modifications to the aircraft structure are under way to reduce weight and improve engine performance. When the GTRE’s joint venture with a leading foreign engine manufacturer for further development is completed in the next four years, the Kaveri will be brought up to a performance level, superior to the GE 404. Fitted with it, the LCA will be truly comparable to the Mirage 2000 and in many respects even superior. And all this in an aircraft much lighter than the Mirage 2000.
Superior
As for network-centric capability, which intrinsically needs indigenous systems for secrecy, security and inter-operability, it is superior in the LCA compared to any aircraft in the IAF’s inventory.
So it is a fallacy to think that we can continue the importing spree and still have such network-centric capability.
As recently as in 2005, the IAF’s requirement for 126 new aircraft was only for an upgraded Mirage 2000. At Rs.120 crore to Rs.140 crore a plane, compared to at least double that amount for any of the aircraft types now bidding for the 126 MRCA, is not the LCA a highly cost-effective fighter for volume induction into the IAF?
As for development costs, the LCA has remained well within the sanctioned $1.2 billion — which is about the lowest anywhere. Time overrun in the strict sense is only by a year or two, despite the sanctions. A first-of-type aircraft of this degree of complexity has not been developed anywhere in the West or in Russia in less than two to three decades.
The F16 series that was inducted into the U.S. Air Force in 1975 is today at Mark 60. That is how aircraft of this level of complexity are improved after induction. That this imperative applies even more to the LCA has to be recognised.
It is for the Prime Minister and the Defence Minister to ensure that this effort is not belittled or scuttled, and that the LCA programme is given all-out support — as successive Prime Ministers have ensured for our atomic energy and space programmes.
(Ashok Parthasarathi was Science Adviser to Prime Minister Indira Gandhi. Vice- Admiral (retired) Raman Puri was Chief of Integrated Defence Staff to the Chairman, Committee of Service Chiefs, remaining closely involved with the inter-service weapons acquisition process from October 2003 to February 2006).