LCA Tejas Mk1 & Mk1A - News and discussions

STEPHEN COHEN

Senior member
Dec 4, 2017
7,405
4,555
If ALSR - Auto low speed recovery trial is done , then it is enough for FOC

Gun trials are just A Formality

If you run out of missiles you won't wait to
Fire your Gun , you will Run away
 

vstol Jockey

Professional
Dec 1, 2017
6,119
12,033
New Delhi
The biggest mods will be toe hook in the forward landing gear!
The present NLG is very week as has been proven in STOBAR launches from SBTF. The speed at which its oleo extends downwards after ramp exit can make it fail. Meaning that the oleo may just fall off after breaking the restraining link. For CATOBAR we will need to further strengthen the nose wheel attachment, add CAT link in front and a restraining link at the rear and also possibly provide for Jump strut.
 

_Anonymous_

Senior Member
Dec 4, 2017
17,189
13,058
Mumbai
PKS on when to expect the FOC -

Another example is that of all bluster that oozes out on either TV or social media whenever the Tejas LCA is discussed. In reality, off-the-record almost all the retired AMs, ACMs & AVM will admit that while the Tejas Mk.1 LCA is a superb flying machine whenever anyone wants to take a joyride, it real-life combat the Mk.1 variant is terribly sub-optimal. They will also admit to 2 more conclusions: 1) it impossible now to integrate the GSH-23 twin-barrel cannon with the airframe, since this work should have been done at the same time as the Mk.1 airframe was being subjected to structural fatigue tests—as per global norms. 2) Despite all the hoo-haa that emanates from ADA, the reality is that both ADA & HAL are absolutely clueless about integrating the Tejas Mk.1A’s mission computer with A) the FADEC of the F404-GE-IN20 turbofan. B) the EL/M-2052 AESA-MMR. C) with the EL/L-8222 ASPJ pod. And this is the most critical developmental challenge because: 1) the mission computer controls the flight-control system & consequently the HOTAS. Consequently, unless the FADEC is communicating with the mission computer, HOTAS will remain non-functional & will have to rely on manual inputs from the pilot. 2) whenever the ASPJ pod is activated for jamming for limited periods, the on-board AESA-MMR will be reqd to be immediately & automatically shut down, lest the jammer jams one’s own AESA-MMR. So, all in all, there’s a lot more developmental work that’s pending & it remains to be seen how quickly IAI/ELTA will be able to sort out such challenges & in what kind of timeframe. For, let’s not forget that 4 years were spent on sorting out similar problems for the Jaguar IS/DARIN-3 project. Hence, I don’t foresee any FOC clearance being given to the Tejas Mk.1, while that for the fully integrated & weaponised Tejas Mk.1A won’t surface till 2024.

You may regurgitate that Black Dog you imbibed a few days ago, if you wish to @randomradio
 

randomradio

Senior Member
Nov 30, 2017
14,207
10,650
India
PKS on when to expect the FOC -

Another example is that of all bluster that oozes out on either TV or social media whenever the Tejas LCA is discussed. In reality, off-the-record almost all the retired AMs, ACMs & AVM will admit that while the Tejas Mk.1 LCA is a superb flying machine whenever anyone wants to take a joyride, it real-life combat the Mk.1 variant is terribly sub-optimal. They will also admit to 2 more conclusions: 1) it impossible now to integrate the GSH-23 twin-barrel cannon with the airframe, since this work should have been done at the same time as the Mk.1 airframe was being subjected to structural fatigue tests—as per global norms. 2) Despite all the hoo-haa that emanates from ADA, the reality is that both ADA & HAL are absolutely clueless about integrating the Tejas Mk.1A’s mission computer with A) the FADEC of the F404-GE-IN20 turbofan. B) the EL/M-2052 AESA-MMR. C) with the EL/L-8222 ASPJ pod. And this is the most critical developmental challenge because: 1) the mission computer controls the flight-control system & consequently the HOTAS. Consequently, unless the FADEC is communicating with the mission computer, HOTAS will remain non-functional & will have to rely on manual inputs from the pilot. 2) whenever the ASPJ pod is activated for jamming for limited periods, the on-board AESA-MMR will be reqd to be immediately & automatically shut down, lest the jammer jams one’s own AESA-MMR. So, all in all, there’s a lot more developmental work that’s pending & it remains to be seen how quickly IAI/ELTA will be able to sort out such challenges & in what kind of timeframe. For, let’s not forget that 4 years were spent on sorting out similar problems for the Jaguar IS/DARIN-3 project. Hence, I don’t foresee any FOC clearance being given to the Tejas Mk.1, while that for the fully integrated & weaponised Tejas Mk.1A won’t surface till 2024.

You may regurgitate that Black Dog you imbibed a few days ago, if you wish to @randomradio

Take PKS with a bag of salt.
 

randomradio

Senior Member
Nov 30, 2017
14,207
10,650
India
Well, if I were you, I'd refute it with facts.

Anybody can say anything they want, there's no point refuting it because it's difficult to confirm it anyway. So he lives in the gaps of knowledge.

The only thing true is the beginning where he says the Mk1 is not up to the mark, which we have known for well over a decade anyway, that's why there's the Mk1A, which barely makes up for the Mk1's deficiencies. The ASPJ jamming the radar is downright ridiculous. We have integrated the same jammer on Russian aircraft like Mig-21 and MKI, and can use both the radar and jammer, no problem, or else there's no point in even carrying it. Considering both the radar, EW suite and jammer will come from Israel, don't you think the Israelis will know what they are doing? So it's obvious he knows jack-all.

Gun, no real problem. But work needs to be done and could take many months.

HOTAS-FADEC, face meets a**. Gripen, T-50 and LCA use the F404 with FADEC, and all three also have HOTAS.

Tejas Mk1A will be flying at the end of this year. First squadron delivery in 2021-22.

Lastly, mission computer (OAC) and FBW (DFCC) are unrelated. Both are separate. So Mr. Clueless all around.

Fly by Wire - Technology | Tejas - India's Light Combat Aircraft
Open Architecture Computer for Avionics - Technology | Tejas - India's Light Combat Aircraft

Take PKS with a bag of salt. He posts good pictures, probably well travelled or knows such people. All accompanied writing, best to ignore.
 

Milspec

सर्वदा शक्तिशाली; सर्वत्र विजय
Moderator
Dec 2, 2017
2,201
2,831
United States
PKS on when to expect the FOC -

Another example is that of all bluster that oozes out on either TV or social media whenever the Tejas LCA is discussed. In reality, off-the-record almost all the retired AMs, ACMs & AVM will admit that while the Tejas Mk.1 LCA is a superb flying machine whenever anyone wants to take a joyride, it real-life combat the Mk.1 variant is terribly sub-optimal. They will also admit to 2 more conclusions: 1) it impossible now to integrate the GSH-23 twin-barrel cannon with the airframe, since this work should have been done at the same time as the Mk.1 airframe was being subjected to structural fatigue tests—as per global norms. 2) Despite all the hoo-haa that emanates from ADA, the reality is that both ADA & HAL are absolutely clueless about integrating the Tejas Mk.1A’s mission computer with A) the FADEC of the F404-GE-IN20 turbofan. B) the EL/M-2052 AESA-MMR. C) with the EL/L-8222 ASPJ pod. And this is the most critical developmental challenge because: 1) the mission computer controls the flight-control system & consequently the HOTAS. Consequently, unless the FADEC is communicating with the mission computer, HOTAS will remain non-functional & will have to rely on manual inputs from the pilot. 2) whenever the ASPJ pod is activated for jamming for limited periods, the on-board AESA-MMR will be reqd to be immediately & automatically shut down, lest the jammer jams one’s own AESA-MMR. So, all in all, there’s a lot more developmental work that’s pending & it remains to be seen how quickly IAI/ELTA will be able to sort out such challenges & in what kind of timeframe. For, let’s not forget that 4 years were spent on sorting out similar problems for the Jaguar IS/DARIN-3 project. Hence, I don’t foresee any FOC clearance being given to the Tejas Mk.1, while that for the fully integrated & weaponised Tejas Mk.1A won’t surface till 2024.

You may regurgitate that Black Dog you imbibed a few days ago, if you wish to @randomradio
hehhe, who writes this bull shit,
1> Guns can be mounted by trunnion frame plate or a trunnion frame bracket on the designated airframe ring point or a wing root. The other option is a pod mounted solution.
Here is bracket mounted GSH30 in Wing root. Although LCA wont be able to install it in wingroot, but nothing stops it from mounting it underbelly.
otr_gun_gsh-301_m04.jpg


Whether internal or pod mounted, it for sure as hell doesn't need fatigue testing for a gun mount.

Whats next fatigue testing of airframe for accepting a different ejection seat?


2> Hotas, means a a throttle lever and control stick with combat and flight control switches - It's an ergonomic system it has nothing to do with fadec or fly by wire, even there the writer is quite off. Fadec incompatibility is complete BS made up by someone, I have never heard of that even as a concern. If flyby wire was non functional on a LCA, an inherently unstable design wouldn't be flying. So the entire concern is rubbish by the writer.
 
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_Anonymous_

Senior Member
Dec 4, 2017
17,189
13,058
Mumbai
hehhe, who writes this bull shit,
1> Guns can be mounted by trunnion frame plate or a trunnion frame bracket on the designated airframe ring point or a wing root. The other option is a pod mounted solution.
Here is bracket mounted GSH30 in Wing root. Although LCA wont be able to install it in wingroot, but nothing stops it from mounting it underbelly.
otr_gun_gsh-301_m04.jpg


Whether internal or pod mounted, it for sure as hell doesn't need fatigue testing for a gun mount.

Whats next fatigue testing of airframe for accepting a different ejection seat?


2> Hotas, means a a throttle lever and control stick with combat and flight control switches - It's an ergonomic system it has nothing to do with fadec or fly by wire, even there the writer is quite off. Fadec incompatibility is complete BS made up by someone, I have never heard of that even as a concern. If flyby wire was non functional on a LCA, an inherently unstable design wouldn't be flying. So the entire concern is rubbish by the writer.
Bravo!! A precise engineering rebuttal. I used to go thru stuff like this in trouble shooting reports by service & R&D personnel in repeat failures on newly commissioned Chiller Packages once upon a time. I doff my hat to you. Makes me nostalgic. Reminds me of what pure techno commercial sales used to be all about at the start of my career before manipulation , corruption & purely commercial terms set in.

PKS is Prasun Sengupta. I'm sure you've heard of him.
 
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Bharath

Technical Staff
Dec 1, 2017
791
999
Boston

Arpit

Vox Populi
Nov 30, 2017
306
282
Delhi
hehhe, who writes this bull shit,
1> Guns can be mounted by trunnion frame plate or a trunnion frame bracket on the designated airframe ring point or a wing root. The other option is a pod mounted solution.
Here is bracket mounted GSH30 in Wing root. Although LCA wont be able to install it in wingroot, but nothing stops it from mounting it underbelly.
otr_gun_gsh-301_m04.jpg


Whether internal or pod mounted, it for sure as hell doesn't need fatigue testing for a gun mount.

Whats next fatigue testing of airframe for accepting a different ejection seat?


2> Hotas, means a a throttle lever and control stick with combat and flight control switches - It's an ergonomic system it has nothing to do with fadec or fly by wire, even there the writer is quite off. Fadec incompatibility is complete BS made up by someone, I have never heard of that even as a concern. If flyby wire was non functional on a LCA, an inherently unstable design wouldn't be flying. So the entire concern is rubbish by the writer.
Sir
What about ACM?

transients. These flight conditions are experienced in certain training
profiles and air combat manoeuvres (ACM). This region accounted for 520 of all
reported compressor stalls and of these, 71% occurred with a CIT below -26*C.
The stall inducing factors were a suspected lack of T2 cutback, coupled vith
inlet distortion associated with the higher angles of attack and aircraft yaw
frequently encountered during ACM.

It is obvious from the flight test and component failure data that pilot surveys,
while better than nothing as a first estimate, are not sufficient to accurately define
engine usage for component lifing purposes. This is not unexpected, since in an environment
with a high pilot workload such as ACM, weapons delivery profiles, or formation flying,
it would be impossible for the pilot to note all throttle or engine speed movements.
Additionally, even if consciously watching gauges, pilots could not see short duration
engine speed exceedances during certain throttle manoeuvres

The F/A-18 flight control system has pitch axis priority; meaning longitudinal
stability is ensured first before the flight control system will attempt to satisfy other
control demands. The longitudinal control system is designed to optimize load factor at
mid to high dynamic pressures. At low dynamic pressures, the schedules are optimized
for air combat maneuvering (ACM), which includes precise attitude control and increased
stick force cues with increasing load factor. At high AOA, AOA feedback is introduced.
The longitudinal commands are measured by stick position with feedbacks of pitch rate, normal acceleration and AOA.


A majority of the departures occur during Basic Fighter Maneuvering (BFM) or ACM
flight resulting in a nose high, low airspeed condition. Pilots lose situational awareness
in a maneuvering fight and the resulting high AOA and low airspeed situation leads to a
departure. Often defensive maneuvers are flown at angles of attack closer to
stall/departure than offensive maneuvers due to the urgency of the situation. Occasionally
departures have occurred due to leading edge flap failures and those incidents were not
utilized in this evaluation of configuration effects.

Figure 27 provides a graphical representation of throttle movement and engine
speed transients during a four minute portion of a typical ground attack training mission,
corresponding to that portion of the Figure 16a flight between the dotted lines. There
i. are a significant number of engine speed excursions, two of which exceed the 30% threshold for influencing the cyclic life usage of the GE analysis indicated in Figure 14. The pilot
survey output however, contains no information of throttle excursions which would effect
component life using the GE analy~sis. Figure 18 illustrates the extent of throttle movements
measured during an ACM 180 engagement. Once again, considerable engine speed cycles
are evident.

Source:
http://www.dtic.mil/dtic/tr/fulltext/u2/a129168.pdf
http://trace.tennessee.edu/cgi/viewcontent.cgi?article=3700&context=utk_gradthes


It looks like to me you need to change FADEC laws as Mission computer give command of ACM mode. One cant use normal FADEC laws to accommodate ACM. @vstol might be able to clear this thing.
 
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Arpit

Vox Populi
Nov 30, 2017
306
282
Delhi
hehhe, who writes this bull shit,
1> Guns can be mounted by trunnion frame plate or a trunnion frame bracket on the designated airframe ring point or a wing root. The other option is a pod mounted solution.
Here is bracket mounted GSH30 in Wing root. Although LCA wont be able to install it in wingroot, but nothing stops it from mounting it underbelly.
otr_gun_gsh-301_m04.jpg


Whether internal or pod mounted, it for sure as hell doesn't need fatigue testing for a gun mount.

Whats next fatigue testing of airframe for accepting a different ejection seat?


2> Hotas, means a a throttle lever and control stick with combat and flight control switches - It's an ergonomic system it has nothing to do with fadec or fly by wire, even there the writer is quite off. Fadec incompatibility is complete BS made up by someone, I have never heard of that even as a concern. If flyby wire was non functional on a LCA, an inherently unstable design wouldn't be flying. So the entire concern is rubbish by the writer.
About the PKS thing about gun, I think he meant if FADEC and radar are not transferring data back to the mission computer, the CCIP cannot be activated. And you have to go with manual mode.

Continously Computed Impact Point (CCIP)

And it require to optimize HOTAS sensitivity with FADEC during ACM mode.
 
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