That is the point, they have not Expanded flight envelope, contrary to your varying combinations hypothesis.

The above can be rephrased as HAL has broadened the flight envelop, but is yet to progress it further.

What were the 400 flights were? Joy rides!!! or as the Air Marshel puts it :

The retired Marshall (not connected to Tejas programme at any time), is quoting generally only. The media report directly doesn’t say that Tejas has performed many tests. It inserted his general statement to imply an incorrect fact.

In other words, note that neither the report nor the respected Air Marshall directly say, “The Tejas has been only taking off and landing since 400 tests”.

Now, as mentioned by the Air Force officer quoted in the 2005 news report, the first 400 tests tested vibration issues, and radio communication. The tests before visiting dignitaries and air-shows since 2001 amount to only 3-4 (you may refer to official website of ADA, which records date, time, duration and Tejas unit number of each test).

How did they progressed to Serial production without completing the flight parameters in Technical Demonstrator???

Technical Demonstrator Vehicles are only TD-1 and TD-2. The PV vehicles, or Prototype vehicles PV-1, PV-2 and PV-3 are also tested. The LSP-1 (Limited Serial Production) is tested in tandem with all 5 earlier models. All vehicles after TD series have progressively superior airframes and improved avionics.

The LSP series of 8 units do not include the initial IAF order of 20 units of Tejas. These are the only ones being manufactured for IAF’s evaluation purposes.

Regarding testing, as of now tests are concentrated towards asymmetrical drop-tank testing, more missile firings, trials in Himalayas and Rajasthan desert after the sea-level trials, and most importantly sensor trials like HUD and HMDS system, besides others. Till now, all on-board systems have exceeded expectations.

References :-

1) DRDO on Tejas, Singapore Air Show, 2008

2) News report originally for ‘Business Standard’ magazine

While the above does make sense, the statement from the article saying that “design and development” of Tejas began in 1992″ does not appear to be the most accurate one (on its own). From what I know, to someone in the west, designing the layout, building & testing wind tunnel models etc would form part of regular design and development phase. But if this was not the case and initiation of design and development was to be considered from cutting of metal, I wonder how LCA would compare with other 4th gen fighters.

vikasrehman, as rayrubik said earlier (and quoted by you), design process concludes with CFD tests, wind tunnels and also small scale models after PD is released : a phase which Tejas completed by 1990. Some authors practically regard 1993 as start date of FSED (as pointed out by rayrubik) or Full Scale Engineering & Design.

Note that the first Tejas rolled out in Nov. 1995, but was grounded for 5 years till its first flight on 4 Jan. 2001. This was due to lack of FBW, for which software was designed, tested on F-16 Vista sims and integrated on it. Hence, this was part of design process also. Also note that since the first flight in Jan 2001, subsequent Tejas prototypes have steadily lost weight as they increased percentage of composites (PV-1 lost 800 kgs weight). In PV-2, fully modular avionics were introduced, unlike older ones on the prior versions of Tejas.

Hence, all this is evolving design, and cannot be substituted by only the PD documentation and scale modeling done upto 1990.

Buraidiah, the article quoted by you is outdated currently. Note that even as of that writing, the Tejas had a capability to carry 5.85 tonnes including engine weight and radar weight. It is still unlikely however, that Tejas is 1 tonne overweight than the stipulated 5.5 tonnes, as larger planes (with lesser composites) like the all-metal JF-17, Gripen and T-50 weigh quite lesser than or equal to 6.5 tonnes.

I think you are blaming the IAF here, for not raising objections before:eek: . How do you know they did not raise it before? here it is refresh your memory

http://www.hindu.com/2007/08/25/stories/2007082563300400.htm

I think these objections, along with the ones raised a only few months back here should have been raised by the IAF a few years back, and not after over 800 flight tests have taken place.

The max. weapon payload of the following planes (some in IAF service) are as follows :-

MiG-29 :- 4,000 kgs.
MiG-27 :- 4,000 kgs.
Tejas :- >4,000 kgs.
T-50 :- 3,000 kgs.
JF-17 :- 3,600 kgs.

From the above, it is clear that as Tejas has superior payload specs., it is superior than the IAF’s existing MiG-29 and MiG-27 planes and is not merely a MiG-21 replacement, as is often incorrectly mentioned by the media (note its max. range also matches that of the above mentioned jets).

Abhimanyu you may want to have a look here
http://www.india-defence.com/reports/3273
Rafael has been selected to supply its Litening targeting pod to equip the Indian air force’s Aeronautical Development Agency-built Tejas light combat aircraft.

The order – of undisclosed value – covers the production of Litening systems for the service’s initial batch of 20 production aircraft

The above order is for production run of 20 planes only. That the Tejas would have Israeli designator pods has been known since many years, as the same were contracted for the Su-30 MKIs since late 1990s.

Is it not obivous to you, that they are made in different eras??

See, Mr. Hormuz also mentioned that the current MiG-29s are also no superior than the Tejas in weapon-load capacity. Only MiG-35 is known to carry 1,600 kgs more armament than Tejas.

LCA has same Engine F-404, Same form of help from Dassault like LM for T-50.
Hell even the flight performance till today is same Mach 1.4, 6G, and 48,000 Feet altitude.

Again note that Tejas weighs 1,000 kgs lighter, and has a smaller wingspan and height than T-50.

Although not to be brought into discussion, the JF-17 also has inferior payload specifications as the Tejas, despite weighing 1,000 kgs more than it, and being almost the same size as an F-16 (check length, height and span).

Even the celebrated authors of “LCA comparable to F-22” Parthasarthy and Raman Puri concede that LCA will better suit as trainer.

The above two authors twice emphasize in their article, that the Tejas can also compete as an MRCA contender, as its technologies are second to none.

Ok, its all become so confusing.

If ‘The actual design and development work of LCA commenced in 1992’, (im particularly refering to design here) then why do we have an article in Flight in 1989 claiming that LCA’s ‘design has been frozen’???

Now from what I understand (and please correct me if Im worng) a lot of design work needs to be done before you can actually freeze a fighter design??? So either the design work started before 1989 for the design to be frozen in 1989 or the person making this claim was not telling the full truth???
Also if the construction of a 1/7 model model started in 1989, what was that model design based upon? Im sure ir wouldn’t have been the result of a simple meeting about what sort of model we should make, and then we’ll refine the design afterwards.

As we discussed earlier, the 1/7 scale model was based on the PD document, which was formalized between Sept. 1987 to 1988. The design was frozen based on that.

The authors in this article mention “design and development” of Tejas began in 1992″, possibly referring to the beginning of the production (or “metal-cutting”) of the full-scale unit. If freezing the paper design, or drawing board design is considered, then that would be the finalization of the PD in 1988.

But most authors usually take the 1993 date i.e. when the full-scale model begun development, as the start date for design. This is because only the on-paper PD may not be sufficient enough to formally end of design stage.

Well you have to ask Kota babu, why he was making false promises to the devotee…don’t you think. He should have known better that without the FSED, how the hell he ordered engines in ’86 and make tall claims of inducting in 1995:eek:

Again, I reiterate that it was the IAF’s delay that led to the production work to begin only in late 1993. The original roll-out of Tejas that was scheduled in 1992, actually happened in 1995.