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A Better Alternative
Before Tejas Mk II is brought in, experts should weigh all the pros and cons
By Air Cmde. (retd.) Parvez Khokhar
Now that sounds coming from the ministry of defence (MoD) and Aeronautical Development Agency (ADA) seem to be suggesting that the Tejas Mk I is just around the corner, the focus seems to be shifting to the Tejas Mk II. This variant appears to be gathering momentum in the eyes of clairvoyant chair-borne pundits, who profess that this will be the panacea for all the ills that beset the indigenous aircraft industry and will also address the desire of the Indian Air Force (IAF) to have a super-duper fighter.
ADA and Hindustan Aeronautics Limited (HAL) have even widely publicised a time schedule for the induction of this aircraft (too fictional to be mentioned). The granting of permission by the MoD to commence this project and its acceptance by the IAF by placing some initial orders, is not in the public domain. In order to take an educated decision on what the Mk II aims to be and the challenges involved therein, it is imperative to comprehend the facts, as they exist today.
ADA and HAL have made public statements that work on the airframe will begin by end 2013. Whilst it is apparent that the qualities envisaged in the Mk II are all commendable, they require a closer examination to comprehend the challenges involved in reaching this target without unacceptable time and cost overruns. So what are the major changes envisaged in the Mk II in order to be a quantum leap over the Mk I?
These are: More powerful engine F-414-GE-INS6; New Flight Control Computer; Upgraded avionics; Retractable In Flight Refuelling probe; On Board Oxygen Generating system (OBOGS); AESA radar; Cockpit upgrade; New Electronic Warfare(EW) suite; and Ability to super cruise (fly supersonic in level flight in dry power).
These changes will lend value throughHigher thrust; More ordnance carrying capacity; Better avionics; Longer endurance with On Board Oxygen Generating System (OBOGS); State-of-the-art radar; Better man-machine interface and situational awareness through larger displays in the cockpit and easier management drills; and Better survivability through better EW suites. This factor will also enhance the operational performance.
ADAs contention that all this can be done within two years is based on the example of the Swedish Gripen NG (called Gripen E for in-service usage). ADA has also sought guidance through consultancy from Saab for the Mk II. Before proceeding further, we need to factor in some extremely relevant points, otherwise this comparison becomes rather odious.
The Gripen E is an off-shoot of the highly successful Gripen A/B/C/D. The Tejas Mk I is yet to enter service.
Saab has over 75-year-old history of design and development of fighter aircraft vis-a-vis ADA/HALs nascent experience in producing fighter aircraft.
ADAs record of non-adherence to consultants recommendations, especially when it runs against their grain and involves redoing certain aspects of work, is well known.
Then there are consultants who merely review your work and either tell you that it is okay or withhold comments that may rock the boat. It is to be seen how much Saab would be involved; ADA should be absolutely clear that Saab will neither build/design this aircraft for them nor give them a blueprint to follow.
Let us take a cursory glance at the summary of how Saab went about making the Gripen E, which has fairly similar improvements as envisaged for the Tejas MK II. The stated aims of the Gripen E were: Increased thrust; Decision support; Sensor fusion; Superior HMI; Improved communication; More weapon stations; Superior target acquisition; Airframe upgrades; External sensors; General systems upgrade; New avionics architecture; and Electronic Warfare
These changes led the demonstrator aircraft (the NGs) to achieve the following:Enhanced range; Morepayload; New sensor suite/weapons/electronic countermeasures; Engine with higher thrust; AESAradar; New avionics system; More internal fuel; and Super cruise ability. This also permitted reduced cost and lead time by 60 per cent, thanks to new processes and new supplier strategy (very significant in the Indian context).
The programme followed a time-bound schedule that went through the following steps:
Early 2006: Demonstrator development started in Saab with the aim to fly in 2008
27 May 2008: Maiden flight of the Demonstrator(NG). This segment of the test programme was concluded in only 79 test flights with the new engine (414), larger internal fuel tank and more pylons (increased payload).
27 October 2009: Introduced AESA (limited version), MAW and SATCOM. Flown and tested in 73 flights including flights with a larger drop tank. Next step planned was to introduce new avionics.
By 19 December 2012 the demo aircraft had accumulated over 250 hours.
15 July 2013: Saab started the assembly of the Next Generation Gripen, the Gripen E. First to be constructed is the front fuselage of the first pre-production test aircraft 39-8.
15 August 2013: Saab claimed they reduced cost and lead time by 60 per cent, thanks to new processes and new supplier strategy
2018: Delivery of first Gripen E planned for the Swedish Air Force. Saab managed the weight issue rather cleverly through extensive use of aluminium alloys and composites for the airframe. The major lesson that this remarkable programme brought was that it is extremely important to work with the customer to achieve success in record time.
Challenges for the Tejas Mk II
ADA has certainly conducted some studies on this subject, but the extent to which they have proceeded and the results achieved are shrouded in secrecy. Educated guesses from within ADA vary from the lets see how it goes to the more horrifying prospect that it may do less than the MK I. The latter view seems to justify ADAs reluctance to even part with the projected improved performance figures. Remember, unlike the Gripen E, the Tejas Mk II will first have to contend with the shortcomings and flaws that it will inherit from the Mk I. These include:
Weight reduction;
New engine F414 fitment requirements;
Re-design of air intakes;
Better cooling of the avionics bay;
Estate management of ancillaries fitted around the engine to facilitate a swift engine change (Gripen engine change takes 33 minutes); and
Brakes
These are only representative and by no means, exhaustive. Corrective measures for all shortfalls will have to be addressed along with the challenges that the new design will throw up.
The new design features would include modification of the fuselage to accommodate the larger and heavier F414 engine. This would entail lengthening the fuselage, strengthening the fuselage and redesigning the contours. More thrust being produced by this engine (35 per cent more than the F404) means more fuel consumed and hence, the necessity for larger capacity fuel tanks. The obvious penalty would be in adding more weight, changing the area ruling (contours of the fuselage) which would increase the drag index, thereby negating some of the advantages of having a more powerful engine. The addition of more weight would be counter-productive. However, some saving grace could be sought from redistribution of segments of the avionics components/LRUs and those of the new radar to get rid of the 200kg ballast that is carried in the nose bay to keep the centre of gravity within limits, an unheard of solution in good modern day fighters, only exception being Chinese fighters.
The air intakes would have to be redesigned to ensure full benefit is derived from the new engine. This is one area that ADA has shied away from doing for decades. It is both understandable and acceptable that they lack expertise in this area, but it has to be addressed, so why not get specialist help for this.
Fool-proof cooling of the avionics bay is a safety requirement, since this area houses much sensitive equipment, including the four channel cards for the quadruple fly-by-wire system of the Digital Flight Control Computer, which, if affected by thermal transfer due to inadequate cooling, can have disastrous consequences. The quadruple control system will come to naught if all four systems fail in quick succession. Other sensitive equipment can also get degraded and thereby, jeopardise mission accomplishment.
Maintenance practices in the Tejas are probably among the most primitive in this class of aircraft and certainly not conducive to operational efficiency. The Gripen requires all of 33 minutes to replace the engine. The Tejas takes a couple of days because of poor estate management of ancillary connections on the engine. With a Hot Refuelling (engine running after landing) and rearming with air-to-air missiles, the Gripen is back in the air in 22 minutes. Hot refueling is not permitted by Indian Oil, who seems to dictate the Tejas operational efficiency. The IAF could circumvent this issue by getting their own refuellers that are manned by IAF personnel. (I wonder whether Indian Oil is aware that air to air refueling does not require the engines to be shut down in the air! So much for their safety practices).
There are a host of other issues that have been swept under the table ever since the first aircraft was designed and manufactured. Unless each one of them is addressed, their ghost will always return to haunt this programme.
So, how does this translate into time required and cost involved?ADA has no clue and that is a charitable observation. Having been brought up for decades on self-delusion, delays and cost overruns, that have always been condoned, they no longer acknowledge the word accountability. HAL keenly aids and abets this philosophy. Before the go-ahead is given to this project, a complete feasibility report must be produced by the two Original Equipment Manufacturers (OEMs), clearly stating the aim of this exercise, with details of changes planned, the improved performance that would accrue and realistic timelines, plus costs.
It would not be out of place, based on past performance, to state that performance, costs and timelines will have to be critically examined and the casual figures bandied about by non-involved individuals/bodies must be totally ignored. If the Gripen E, with Saabs extensive experience, is realistically pitched at 12 years from conception to manufacture to delivery of first aircraft to the Swedish Air Force, it would behove ADA/HAL to add on a few more years to the Tejas Mk II. At a conservative estimate of 16 years (your guess is as good as mine), does this version of the aircraft really add value to the IAF, when it would have already inducted the fifth generation aircraft?
A Viable Alternative
The rationale of making the Tejas MK II is centred around the Indian Navys requirement of having a greater initial acceleration for deck operations. Hence, the choice of a more powerful and bigger engine, the F414. The IAF has piggybacked on this solution since it promises a greater all round performance.
The navys requirement is well focused on the engine, though they would not be reluctant to avail of any other benefit that this aircraft would bring as a bonus. The IAFs configuration for the MK II, though discussed internally, is still not frozen. Therefore, to consider a viable alternative is not too late.Give a serious thought to modifying the Mk I with all the changes envisaged for the Mk II, other than the engine change. The only major challenge is to redesign the air intakes to ensure optimum pressure recovery. The rest would entail only modifications and improvements.
The question that comes up is whether a serious study has been done to explore this alternative. It would not need rocket science to presume that the time, effort and money required to do this would be far less than design and development of a new aircraft. Whether this version is called theMK IAor Mk II is of no consequence, since such nomenclature is pure semantics.
The prime focus will have to be on ensuring that the rated thrust is allowed to be produced by the engine. The Swedish version of the F404 is the RM 12, made by Volvo. Some tweaking by Volvo has enhanced the dry thrust from 49.9 kN to 54kN and in the after burner regime, from 78.7kN to 80.5kN. It has also strengthened fan modules to withstand bird strikes. The F404-IN-20 also incorporates these modifications, but the Tejas Mk I intake design does not allow this full thrust to be built up. Hence, it is mandatory to redesign the intakes. Both the Gripen and the older version of the F-18 have air intakes that permit optimum pressure recovery. Can ADA not consult both Saab and Boeing to overcome this problem?
The other unresolved issues that have defied a solution are not because of ADAs capability, but their reluctance to address them, since it is far easier to sweep them under the carpet, to be looked at later. Later has arrived now and procrastination cannot be condoned any further. The work force, which is familiar with the MK I and is relatively unoccupied, can now be gainfully diverted to carrying out structural and other reviews to resolve pending issues, instead of waiting to tackle the MK II, as and when it emerges.
Will this avatar of the Tejas meet the requirements of the Indian Navy? Has ADA measured what the static thrust of the engine is in the MK I as of now and determined how short it falls of the manufacturers figure? Unless that is known, how can we aim to achieve the latter? A comprehensive study would provide the answer. In the event that the enhanced initial thrust still falls short of the navys requirement, the F 414 may be the only answer, but not in the form that ADA envisages the Tejas Mk II. Before giving a green light to the Tejas Mk II, a transparent study of the enhanced performance, with specific facts and figures, along with a realistic timeframe and cost, must be scrutinised by a competent body of the users (IAF and IN) and financial wizards, lest the taxpayers money is again squandered away. Is anyone listening?
Subscribers only - From Force Magazine
Before Tejas Mk II is brought in, experts should weigh all the pros and cons
By Air Cmde. (retd.) Parvez Khokhar
Now that sounds coming from the ministry of defence (MoD) and Aeronautical Development Agency (ADA) seem to be suggesting that the Tejas Mk I is just around the corner, the focus seems to be shifting to the Tejas Mk II. This variant appears to be gathering momentum in the eyes of clairvoyant chair-borne pundits, who profess that this will be the panacea for all the ills that beset the indigenous aircraft industry and will also address the desire of the Indian Air Force (IAF) to have a super-duper fighter.
ADA and Hindustan Aeronautics Limited (HAL) have even widely publicised a time schedule for the induction of this aircraft (too fictional to be mentioned). The granting of permission by the MoD to commence this project and its acceptance by the IAF by placing some initial orders, is not in the public domain. In order to take an educated decision on what the Mk II aims to be and the challenges involved therein, it is imperative to comprehend the facts, as they exist today.
ADA and HAL have made public statements that work on the airframe will begin by end 2013. Whilst it is apparent that the qualities envisaged in the Mk II are all commendable, they require a closer examination to comprehend the challenges involved in reaching this target without unacceptable time and cost overruns. So what are the major changes envisaged in the Mk II in order to be a quantum leap over the Mk I?
These are: More powerful engine F-414-GE-INS6; New Flight Control Computer; Upgraded avionics; Retractable In Flight Refuelling probe; On Board Oxygen Generating system (OBOGS); AESA radar; Cockpit upgrade; New Electronic Warfare(EW) suite; and Ability to super cruise (fly supersonic in level flight in dry power).
These changes will lend value throughHigher thrust; More ordnance carrying capacity; Better avionics; Longer endurance with On Board Oxygen Generating System (OBOGS); State-of-the-art radar; Better man-machine interface and situational awareness through larger displays in the cockpit and easier management drills; and Better survivability through better EW suites. This factor will also enhance the operational performance.
ADAs contention that all this can be done within two years is based on the example of the Swedish Gripen NG (called Gripen E for in-service usage). ADA has also sought guidance through consultancy from Saab for the Mk II. Before proceeding further, we need to factor in some extremely relevant points, otherwise this comparison becomes rather odious.
The Gripen E is an off-shoot of the highly successful Gripen A/B/C/D. The Tejas Mk I is yet to enter service.
Saab has over 75-year-old history of design and development of fighter aircraft vis-a-vis ADA/HALs nascent experience in producing fighter aircraft.
ADAs record of non-adherence to consultants recommendations, especially when it runs against their grain and involves redoing certain aspects of work, is well known.
Then there are consultants who merely review your work and either tell you that it is okay or withhold comments that may rock the boat. It is to be seen how much Saab would be involved; ADA should be absolutely clear that Saab will neither build/design this aircraft for them nor give them a blueprint to follow.
Let us take a cursory glance at the summary of how Saab went about making the Gripen E, which has fairly similar improvements as envisaged for the Tejas MK II. The stated aims of the Gripen E were: Increased thrust; Decision support; Sensor fusion; Superior HMI; Improved communication; More weapon stations; Superior target acquisition; Airframe upgrades; External sensors; General systems upgrade; New avionics architecture; and Electronic Warfare
These changes led the demonstrator aircraft (the NGs) to achieve the following:Enhanced range; Morepayload; New sensor suite/weapons/electronic countermeasures; Engine with higher thrust; AESAradar; New avionics system; More internal fuel; and Super cruise ability. This also permitted reduced cost and lead time by 60 per cent, thanks to new processes and new supplier strategy (very significant in the Indian context).
The programme followed a time-bound schedule that went through the following steps:
Early 2006: Demonstrator development started in Saab with the aim to fly in 2008
27 May 2008: Maiden flight of the Demonstrator(NG). This segment of the test programme was concluded in only 79 test flights with the new engine (414), larger internal fuel tank and more pylons (increased payload).
27 October 2009: Introduced AESA (limited version), MAW and SATCOM. Flown and tested in 73 flights including flights with a larger drop tank. Next step planned was to introduce new avionics.
By 19 December 2012 the demo aircraft had accumulated over 250 hours.
15 July 2013: Saab started the assembly of the Next Generation Gripen, the Gripen E. First to be constructed is the front fuselage of the first pre-production test aircraft 39-8.
15 August 2013: Saab claimed they reduced cost and lead time by 60 per cent, thanks to new processes and new supplier strategy
2018: Delivery of first Gripen E planned for the Swedish Air Force. Saab managed the weight issue rather cleverly through extensive use of aluminium alloys and composites for the airframe. The major lesson that this remarkable programme brought was that it is extremely important to work with the customer to achieve success in record time.
Challenges for the Tejas Mk II
ADA has certainly conducted some studies on this subject, but the extent to which they have proceeded and the results achieved are shrouded in secrecy. Educated guesses from within ADA vary from the lets see how it goes to the more horrifying prospect that it may do less than the MK I. The latter view seems to justify ADAs reluctance to even part with the projected improved performance figures. Remember, unlike the Gripen E, the Tejas Mk II will first have to contend with the shortcomings and flaws that it will inherit from the Mk I. These include:
Weight reduction;
New engine F414 fitment requirements;
Re-design of air intakes;
Better cooling of the avionics bay;
Estate management of ancillaries fitted around the engine to facilitate a swift engine change (Gripen engine change takes 33 minutes); and
Brakes
These are only representative and by no means, exhaustive. Corrective measures for all shortfalls will have to be addressed along with the challenges that the new design will throw up.
The new design features would include modification of the fuselage to accommodate the larger and heavier F414 engine. This would entail lengthening the fuselage, strengthening the fuselage and redesigning the contours. More thrust being produced by this engine (35 per cent more than the F404) means more fuel consumed and hence, the necessity for larger capacity fuel tanks. The obvious penalty would be in adding more weight, changing the area ruling (contours of the fuselage) which would increase the drag index, thereby negating some of the advantages of having a more powerful engine. The addition of more weight would be counter-productive. However, some saving grace could be sought from redistribution of segments of the avionics components/LRUs and those of the new radar to get rid of the 200kg ballast that is carried in the nose bay to keep the centre of gravity within limits, an unheard of solution in good modern day fighters, only exception being Chinese fighters.
The air intakes would have to be redesigned to ensure full benefit is derived from the new engine. This is one area that ADA has shied away from doing for decades. It is both understandable and acceptable that they lack expertise in this area, but it has to be addressed, so why not get specialist help for this.
Fool-proof cooling of the avionics bay is a safety requirement, since this area houses much sensitive equipment, including the four channel cards for the quadruple fly-by-wire system of the Digital Flight Control Computer, which, if affected by thermal transfer due to inadequate cooling, can have disastrous consequences. The quadruple control system will come to naught if all four systems fail in quick succession. Other sensitive equipment can also get degraded and thereby, jeopardise mission accomplishment.
Maintenance practices in the Tejas are probably among the most primitive in this class of aircraft and certainly not conducive to operational efficiency. The Gripen requires all of 33 minutes to replace the engine. The Tejas takes a couple of days because of poor estate management of ancillary connections on the engine. With a Hot Refuelling (engine running after landing) and rearming with air-to-air missiles, the Gripen is back in the air in 22 minutes. Hot refueling is not permitted by Indian Oil, who seems to dictate the Tejas operational efficiency. The IAF could circumvent this issue by getting their own refuellers that are manned by IAF personnel. (I wonder whether Indian Oil is aware that air to air refueling does not require the engines to be shut down in the air! So much for their safety practices).
There are a host of other issues that have been swept under the table ever since the first aircraft was designed and manufactured. Unless each one of them is addressed, their ghost will always return to haunt this programme.
So, how does this translate into time required and cost involved?ADA has no clue and that is a charitable observation. Having been brought up for decades on self-delusion, delays and cost overruns, that have always been condoned, they no longer acknowledge the word accountability. HAL keenly aids and abets this philosophy. Before the go-ahead is given to this project, a complete feasibility report must be produced by the two Original Equipment Manufacturers (OEMs), clearly stating the aim of this exercise, with details of changes planned, the improved performance that would accrue and realistic timelines, plus costs.
It would not be out of place, based on past performance, to state that performance, costs and timelines will have to be critically examined and the casual figures bandied about by non-involved individuals/bodies must be totally ignored. If the Gripen E, with Saabs extensive experience, is realistically pitched at 12 years from conception to manufacture to delivery of first aircraft to the Swedish Air Force, it would behove ADA/HAL to add on a few more years to the Tejas Mk II. At a conservative estimate of 16 years (your guess is as good as mine), does this version of the aircraft really add value to the IAF, when it would have already inducted the fifth generation aircraft?
A Viable Alternative
The rationale of making the Tejas MK II is centred around the Indian Navys requirement of having a greater initial acceleration for deck operations. Hence, the choice of a more powerful and bigger engine, the F414. The IAF has piggybacked on this solution since it promises a greater all round performance.
The navys requirement is well focused on the engine, though they would not be reluctant to avail of any other benefit that this aircraft would bring as a bonus. The IAFs configuration for the MK II, though discussed internally, is still not frozen. Therefore, to consider a viable alternative is not too late.Give a serious thought to modifying the Mk I with all the changes envisaged for the Mk II, other than the engine change. The only major challenge is to redesign the air intakes to ensure optimum pressure recovery. The rest would entail only modifications and improvements.
The question that comes up is whether a serious study has been done to explore this alternative. It would not need rocket science to presume that the time, effort and money required to do this would be far less than design and development of a new aircraft. Whether this version is called theMK IAor Mk II is of no consequence, since such nomenclature is pure semantics.
The prime focus will have to be on ensuring that the rated thrust is allowed to be produced by the engine. The Swedish version of the F404 is the RM 12, made by Volvo. Some tweaking by Volvo has enhanced the dry thrust from 49.9 kN to 54kN and in the after burner regime, from 78.7kN to 80.5kN. It has also strengthened fan modules to withstand bird strikes. The F404-IN-20 also incorporates these modifications, but the Tejas Mk I intake design does not allow this full thrust to be built up. Hence, it is mandatory to redesign the intakes. Both the Gripen and the older version of the F-18 have air intakes that permit optimum pressure recovery. Can ADA not consult both Saab and Boeing to overcome this problem?
The other unresolved issues that have defied a solution are not because of ADAs capability, but their reluctance to address them, since it is far easier to sweep them under the carpet, to be looked at later. Later has arrived now and procrastination cannot be condoned any further. The work force, which is familiar with the MK I and is relatively unoccupied, can now be gainfully diverted to carrying out structural and other reviews to resolve pending issues, instead of waiting to tackle the MK II, as and when it emerges.
Will this avatar of the Tejas meet the requirements of the Indian Navy? Has ADA measured what the static thrust of the engine is in the MK I as of now and determined how short it falls of the manufacturers figure? Unless that is known, how can we aim to achieve the latter? A comprehensive study would provide the answer. In the event that the enhanced initial thrust still falls short of the navys requirement, the F 414 may be the only answer, but not in the form that ADA envisages the Tejas Mk II. Before giving a green light to the Tejas Mk II, a transparent study of the enhanced performance, with specific facts and figures, along with a realistic timeframe and cost, must be scrutinised by a competent body of the users (IAF and IN) and financial wizards, lest the taxpayers money is again squandered away. Is anyone listening?
Subscribers only - From Force Magazine