HAL Tejas | Updates, News & Discussions-[Thread 2]

[Abingdonboy]

IAF Vs IN
View attachment 191446
View attachment 191447

From this angle you can really see how over engineered that landing gear is on the NLCA at the moment.

------------------

 

[Abingdonboy]

 

[Krate M]

@sancho let's see what new information comes out of aeroindia.

 

[sancho]

From this angle you can really see how over engineered that landing gear is on the NLCA at the moment.

N-LCA NP2, Mig 29K, Rafale M, not to scale though but gives a good comparison.

 

[sancho]

PART 1: Big Surprises In LCA Navy NP1's Ski-Jump Fight

When the first prototype of India's LCA Navy (NP1) roared off the ski-jump at the Shore-based Test Facility (SBTF) for the first time on December 20 last year, no one from the team observing the jet from the flightline and from telemetry stations knew that something unseen had happened. Something that would only become known later in the day when performance data was analysed. And it was good, solid news, much needed for a team that has seen little more than questions, derision and barely veiled bemusement. Importantly, it was the first time the team felt it had an answer to the 'what use is this platform, really?' question...

...And that's where it gets interesting

Top sources on the team say the NP1 was flown a few times conventially before the ski-jump test to soak up the thick sea-level air in Goa. As expected, engine performance was markedly better. Spirits were high, but as has become the norm on milestone tests in the Tejas programme, there was pervasive nervousness. Surprises can be nasty. And the ski-jump test would leave no recovery time if something went wrong. As the Team says, "The first attempt at any new activity is fraught with uncertainties and potential surprises. Given the 'leap off the edge' nature of the first launch, all the major possibilities of failure were identified and options to handle them were built into the plan."
The test flight team decided to lock 5.7 degrees as the minimum climb angle for the NP1 once it made the leap off the ski-jump. When the aircraft actually did roar into the sky, the actual minimum climb angle was observed to be in excess of 10 degrees. Also, the NP1 achieved an angle of attack after ramp exit of 21.6 degrees, giving the team healthy new margins to work with in terms of performance. Simply put, the aircraft performed better than the team ever thought it could.
Now you can argue that safety margins always allow for bumps in performance, but the number crunch that evening demonstrated that the NP1 had exceeded expectations healthily...

...The Indian Navy, which has ordered six of LCA Navy Mk.1 has indicated, albeit unofficially, that the Mk.1 platform is likely never to see actual carrier service. While the performance surprises of December aren't likely to change that, the numbers have changed. And that's something.

LIVEFIST: PART 1: Big Surprises In LCA Navy NP1's Ski-Jump Fight

 

[gslv mk3]

From this angle you can really see how over engineered that landing gear is on the NLCA at the moment.

I don't think it is over engineered...

 

[Didact]

I don't think it is over engineered...

Nah, it probably is. And for good reason too. It's quite common to over-engineer a prototype, to add a certain extra layer of safety if you will. As more and more test data is collected and analysed and the exact parameters of loading and shock the structure will have to undergo, the prototype is slimmed down.

I've seen far simpler, and cheaper shock absorbing systems, and subsystems being over-engineered to a factor of safety 6 or even 9, when perhaps 1.1 or 1.5 was required.

 

[Abingdonboy]

I don't think it is over engineered...

When I say "over engineered" I am directly quoting the chief test pilot of the NFTC:

For the Mk.1 the LG were over engineered a) because this is a prototype but more importantly b) because the IN had little say in the design of the Mk.1 (which NP-1 and 2 are based on) so there has been little strengthening of the actual airframe for the NP-1/2 meaning a grossly over engineered LG needed to be designed to absorb the impact itself without passing the load into the airframe. The IN has had more say in the Mk.2 so this extreme LG won't be needed.

 

[Stephen Cohen]

@sancho let's see what new information comes out of aeroindia.

We really need some information on MK 2

 

[Krate M]

We really need some information on MK 2

True dat. Apparently the specs for this have been frozen and design finalized. Let's hope that info comes out with more details.

 

[Echo_419]

True dat. Apparently the specs for this have been frozen and design finalized. Let's hope that info comes out with more details.

You have a link for the Specs frozed Claim

 

[Krate M]

You have a link for the Specs frozed Claim

Nope just rumors about this.

 

[PARIKRAMA]

Tuesday, February 10, 2015

The LCA Navy NP1's carrier compatibility test off the ski-jump in Goa last month yielded masses of valuable data for a team that hasn't been able to put the aircraft into the air even a fraction of the number of times it would have liked to by now. But while there was plenty to be at least somewhat cheered about, there were two major areas that the flight drew attention to. Two areas the team is focusing on fixing with all its resources:



1. The Control Law and Flight Control System (FCS) Software needs additional coding and updating to handle the higher performance of the platform. "This will enable extracting the best performance of the aircraft in a safe manner as the margins are progressively reduced," say sources on the team.

2. The second take-away was mechanical, and just as crucial: the NP1's nose landing gear extension routine was faster than predicted or expected. Sources on the team confirm that, "Minor modifications to the nose landing gear are in progress and would be available on the aircraft by end Jan 15."

3. Another lesson learned, according to team sources, is that design teams will need to be "even more pragmatic in keeping margins as excess reserves get compounded and could lead to load exceedence."

4. The team is also considering excessive airspeed to be something to look out for. "While on first appearances, excessive airspeed appears to be harmless, it could aggravate aircraft control problems if flight control failures are encountered," team sources said.

Once the 2 tangible fixes are complete, and operating procedures on the other two are in place, the scene shifts back to Goa in March for more ski jump flights, where the flight test team will work towards reducing margins to arrive at final performance levels -- the first final, or close to final operating parameters of the LCA Navy. "Also, it is planned to initiate activities towards arrested recovery starting with dummy approaches on the landing area, ‘taxi-in’ arrester hook engagements on to the arrester wire at the SBTF and final flight engagement," say team sources.

Questions have been raised over whether 'surprise' angle of attack and climb performance actually demonstrated problems with simulation studies, team sources said, "Extensive simulations had been made to predict landing gear loads and the behaviour of all other systems during the ski jump launch. The aircraft was extensively instrumented to enable validation of simulation. The landing gear loads and other system behaviour obtained from the actual ski jump launch were close to prediction."

Series concludes tomorrow with Part 3: The LCA Navy Mk.2

LIVEFIST: PART 2: The Four 'Fixes' After LCA Navy's Ski-Jump Flight

 

[Krate M]

I just noticed one small but very important thing.
The NPs have Nausena clearly written on them. A big reminder of the ownership of the program and pride of ownership of Navy.
It is ours, shown in plain bold visible text. Showing that this program is a part of Indian Navy.

Fills my heart with pride for the Navy.

 

[Echo_419]

Nope just rumors about this.

Thx anyway