BlackArcherHJT-36 Sitara to achieve IOC in July 2011.
‘Indigenous Jet Trainer to get Initial Clearance by July’
Published: Februrary 2011Bangalore. India’s indigenous intermediate jet trainer (IJT) is all set to obtain its initial clearance for air force pilots to start operational flying on the aircraft by July this year, 14 Years after the government Sanctioned the Project, a top commander said Thursday.
The manufacturer, Hindustan Aeronautics Limited (HAL) is “very sure” about Initial Operational Clearance (IOC) for the IJT by July, the Indian Air Force (IAF) chief, Air Chief Marshal P.V. Naik told reporters at the AeroIndia trade show at the Yelahanka air base here.
HAL began designing of the IJT in 1997 and suffered two mishaps in 2007 and 2009. The jet will now be ready for induction into the IAF in another two more years.
The IJT’s two prototypes suffered minor crashes. The first took place in February 2007 when the Prototype-I suffered damage when its canopy flew off soon during take-off from Yelahanka. The aircraft veered to its right, bust a tyre, damaged both its wings and finally collapsed in a heap of rubble. Fortunately, the pilot escaped without injury.
The second accident happened in February 2009 when the Prototype-II landed on its belly during a routine sortie. The aircraft suffered structural damage to its undercarriage and a wing.
“After the minor incidents, the project picked up speed with the flight trials finally getting over. We want its spin capability to improve and HAL is sure it can do it in a month or two. So more or less, IJT is ready for IOC,” the IAF deputy chief, Air Marshal R.K. Sharma, said.
The IJT is a stage-II trainer for rookie pilots before they graduate onto the Hawk advanced jet trainer (IJT), is a tandem seat, all metallic aircraft for general flying and training. It can also be used for formation flying, instrument and cloud flying, tactical flying, night flying and basic air-to-ground and air-to-air armament training.
With a maximum speed of 750 kmph, it has an altitude ceiling of 9 km. The maximum take-off weight at 5,100 kg, including 1,000 kg of armaments at five hard points. It can also carry drop tanks.
A conventional configuration aircraft incorporating manual flight controls, its cockpit is ergonomically designed, air conditioned and pressurised. It is equipped with lightweight ejection seats, with an avionics suite that introduces pilots to a cockpit environment of modern combat aircraft and cues for weapons delivery.
BlackArcherI haven’t made my mind up on anything my friend. What the DRDO pdf says –
Anyone can deduce from that that the initial design was not made with low RCS in mind but in the changing environment they managed to bring it down a bit by modifying some shape aspects of the original design. The second part talks about RAM coatings.
So what ?! are you trying to say that ANY of the Euro-canards were designed keeping RCS in mind initially ?! That’s plain lies. RCS was hardly even a design issue back in the 1980s when ALL the Eurocanards and the LCA were originally conceived.
BlackArchersounds like after thought and using RAM coating they are even reducing MIG 21s RCS that doesn’t make Mig 21 designed to be low RCS.
Oh and Ajay I was only refuting Booms point of serpentine intake, the Y shaped intake was explained by some one 2 pages back.
so when DRDO claims that they’ve designed parts with RCS reduction in mind, then its not a big deal.
But of course, you’ll lap it up with a spoon when Saab or EADS say that they do it. :rolleyes:
No use arguing with anyone who has already made up his mind.
BlackArcherTerrific info on the Tejas in this month’s DRDO new technology focus.
DRDO Technology focus on LCA
Quadbike would be very interested in seeing on the third page that in fact RCS reduction techniques HAVE been used on the LCA.
Shape modification has been carried out keeping in mind RCS and RCS has been brought down significantly this way.
And a facility has been established for coating Indium-Tin-Oxide (ITO) on the Tejas’ canopy and windshield to reduce RCS reflection from the cockpit.
BlackArcherIt doesn’t say the story is from Neelam Matthews.
And secondly if everything was fine and dandy with the MK1 the IAF will not be wanting an MK2 with higher thrust.
Neelam Matthews is the main writer who wrote the article on the Tejas not meeting performance requirements.
Who said that everything is fine with the Mk1 ? No one says that it doesn’t have issues with drag. The aerodynamic refinements with better wing-body blending, improving of slenderness ratio, the higher thrust engine are all aimed at improving the performance shortfalls.
But that doesn’t mean that it will not reach 8Gs or not be able to reach its agreed upon STR values when the entire FOC envelope has been opened up and software is at the final most mature level.
BlackArcherthat x1.5 sounds like a test for gust loads (if i remember JAR 25) …What was the aiframe fatigue tested too?
no no..gust loads are not 1.5 times of limit loads. The 1.5 times of limit load (9Gs) to which the airframe is designed to is called the Ultimate load. The wing structure has to sustain 1.5 times of that 9G load for something like 3 seconds to be certified. It won’t ever see 13.5G loads in service, but without that test, there will be no certification.
ANd as things stand, the LCA’s Ground structural test with a dedicated static test specimen was successful at 13 Gs.
BlackArcherIts not about Physics its Tejas falling short of requirements and therefore needing a higher thrust engine to hopefully take care of it.
Are you saying AW&ST are running a bogus story
As things stand, it’s full envelope hasn’t been explored as yet. The agreed limits between ADA, CEMILAC and IAF for IOC were these:
AoA (alpha)- 22 deg and this was achieved
Gs – 6 Gs and this was achieved
These were the limits that were to be reached for IOC. For FOC, G limit will be 8.
And till they do that, the FCS will limit it from pulling more Gs and that will automatically limit STR.
As simple as that. Neelam Matthews of AW&ST is not a lady whose reports are to be taken as the gospel truth. She has made such blooming errors that they really put her reliability at question.
BlackArcherfair enough, was wrong to repeat the figure of 300% that i had read like parrot fashion my mistake, however still do not understand the issues and why for as the issues.
Also it takes just as much (or lack off) experience in manufacturing (in aerospace, not some un related domain) to defend something on this thread as it does to critique it…
I’m glad you understand. The problem is that some daft media guy cannot understand that in all major projects, funding does not happen to be provided up front all at the same time.
AT various stages of the project, more money is released based on how the goals of the previous stage were achieved, or not achieved.
The idiot who wrote that report took the money figure allocated for the FIRST stage, assumed that that meant that the ENTIRE program had to be developed in that amount, and since it didn’t, calculated a 300% increase in budget !! 😮 (I know, our media can be among the most ignorant lot anywhere)
Its like saying that if you agreed to buy your car and paid a first installment of Rs 1,000, and eventually went on to pay Rs 3,00,000 in other installments, then you went over-budget by 300%.
BlackArcherLCA has been tested on ground upto 12Gs. so that isn’t true. Am really lazy for the source and recalling from memory. help yourself in case you weren’t trolling.
Actually Roylarson, small correction- its been tested to 13 Gs (~1.5 times of 9Gs dynamic load factor) on ground structural rigs and the structure has passed.
This is from AI-11 seminar.
BlackArcherclearly indicates its not an issue with G limit expansion.
feel free to believe whatever you want. I cannot really educate you on every single aspect. You want to believe that physics only applies to the Tejas and not to the F-16 or Gripen, then its your choice really !
BlackArchertheir was a budget their was a goal, if they have gone 300% over the initial budget but met the time lines and design performance goals (that they themselves sold to the world) then I would not bother saying anything.
If the same people run the MCA as those that ran the LCA then yes I believe the AMCA will have little or no hose save for guidance from a external company…
Frankly the credibility of the LCA team and project management is shot to shreads…
Out of the major systems, the Radar has now had to be developed as part of a JV due to issues, the Kaveri also had issues and has had to be developed as part of a JV and the one thing the LCA team kept boasting about (% of composite) has come back to bite them to the point that the aircraft is 1500Kgs over its initial design weight and and not able to perform as per their design targets.
so lets do one thing- why don’t you tabulate how much the initial total project estimate was. Keep in mind that funds were allocated at separate time-intervals.
1) Initial funds for Feasibility studies
2) Funds for initial design
3) Funds for detailed design
4) Funds for building initial 2 TD prototypes
And in all these, from Air Marshal Rajkumar as well as various Parliamentary reports, ADA actually UNDERSPENT !!!
They used money allocated for these activities and in fact built 1 more aircraft extra with the same money allocated (at least Rs 100 crore less than allocated money)
After the TD phase, the actual Production phase began. Here, more funds were released, which allowed a prototype that proved technology (TD) to go to a proper prototype that represented a production standard vehicle (PVs).
The claim about 300% over budget is patent bull****, and those who repeat it like parrots are either ignorant (which is fine, not everyone knows the facts) or simply deliberately ignoring the facts.
As far as the media guys who came up with that claim go- well, one doesn’t really need a degree in economics to write about economics in Indian media. Just like you don’t need any production experience or engineering knowledge to criticize a program on this thread.
BlackArcherwhy non-sense?
you think your diddly fancy FCSs system would allow you to pull more Gs than your natural aircraft is capable?
My suspicion is Tejas’s aerodynamics and structure can not achieve its designed capability.
or look at it from pure physics. example:
you have a 10 ton aircraft that is designed to generated 90 tons of lift. thus achieving 9 Gs.
if you are 3 ton overweight. assume you can still generate 90 tons of lift. you can only physically achieve 6.9 gs with same margins.this is simple physics folks.
Its nonsense because you’re using wildly wrong figures just to suit your argument. And the diddly fancy FCS will not allow you to pull more Gs than has been tested during test flights, pure and simple. Only small over-ride values are allowed (from Saab test pilot Ola Ringell’s seminar).
Because the Tejas’s empty weight is confirmed to be 6560 kgs from AI-11. That is higher than what the design goal was, but it is still well within the range of other similar fighters. The T-50 Golden Eagle is 6500 kgs, JF-17 is around 6600 kgs and Gripen C/D are around the same figure. Of these, the T-50, JF-17 are also supposed to be +8G/-3G fighters only.
As and when more of the envelope is opened up and FCS modified accordingly, the Tejas will get to 8Gs. Just as it was done on the Gripen.
BlackArcherI dont see how anyone can think the engineers could have added canards if they wanted to on a project that is 300% over budget, significantly to the right of the baseline deadlines with a extra weight of 1500 Kgs relative to its original design intent.
Reality is that the engineers have a lot of work to do to produce the aircraft originally promised back in the 80s and 90s.
They would be trying to keep the problem as simple as possible and concentrating on the real issues.
300% overbudget huh ?
So you are one of those who believe that the Tejas program was supposed to be developed using Rs 500 crore of funding ? :rolleyes:
Then maybe you’ll want to start talking about how the AMCA will also be way over-budget, since its initial budget is for around the same amount.
Ridiculous, really !
BlackArcherpulling a lower Gs means either your lift curve prediction is wrong or your structure strength is off. either way shows bit of incompetence.
nonsense. you pull lower Gs because you have not yet fully explored the entire flight envelope. As and when that is opened up further, the FCS will allow more Gs to be pulled.
Or do I need to post links to Gripen flight tests where it was shown that a Gripen B was limited to 7Gs till it’s FCS allowed it to go to 9Gs AFTER testing was complete and software changes were made ? :rolleyes:
BlackArcherThen how come it cannot match the performance of a Gripen C/D with a similar thrust engine.
Because it has not yet reached FOC.
Because it has not yet been tested at more than 6.9Gs or certified to pull more. The airframe may be able to do that, but the FCS will not allow it to do so. Its called an MLL in the Gripen and also does the same. Till the time that the Gripen was not tested to 9Gs, its MLL (Load Limiter) wouldn’t allow its pilot to pull more than whatever it was certified to either.
The pilot could yank on the stick to the end, but the aircraft Gs would be limited by the FCS.
And because it has not yet been through spin tests, after which its AoA limits are supposed to be 26 deg / -9 deg or thereabouts (don’t remember the exact figures, but they were mentioned sometime recently).
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