JF-17 Thunder Multirole Fighter [Thread 5]

[Munir]

like i mentioned it before as well, those stains came from OIL drains, not Fuel drains.
Fuel system is a very complicated thing, but i assure you it doesn't work the way you suggested.

And this is a PT-04
you can see the flares are installed, or at least that yellow cap is gone.
It is odd why PAF still hasn't installed chaff/flares on it.

Please enlighten me with some prove that it is oil drains... Why will an RD93 dump oil in the air?

 

[razgriz19]

Please enlighten me with some prove that it is oil drains... Why will an RD93 dump oil in the air?

( I took this picture)
737-800 engine underbelly.
These drain holes are called case drains. Anything, be it fuel or oil, that leaks goes through here to atmosphere.
I clean these stains quite frequently.

The reason I said its most likely oil is because, turbine bearing are called labyrinth bearings, meaning they are sealed by the moving air. When the engine shuts down, oil is suppose to flow down so the scavenge pump can pick it up, however some of it drips inside the engine. Engineers decided to drain that oil to atmosphere, instead of sending it to the hot section or combustion chamber.

Fuel also comes out, You are correct. However its mostly oil that makes a mess (Jf-17 is an example)

I will try to take another picture of oil sitting inside the engine. Its not good for the engine, but its "normal" according to the mechanics where i work

 

[Donatello]

Please enlighten me with some prove that it is oil drains... Why will an RD93 dump oil in the air?

It is not intentional, rather a consequence of running the engine at a wide variety of speeds. Commercial airliners once in the air have a near constant engine load. For fighter aircraft like JF-17 (especially at airshows) engine speeds vary quite a lot. Thus any oil not being able to go back has to be let off rather than going into wrong hot chambers (as the case in Qantas 32 Airbus A380 incident)

What razgriz is saying makes sense since turbofan engine oils are usually topped up as it gets low.

The real question is why is it so prevalent on JF-17 and not other aircraft that PAF operates, i.e F-7, Mirage, F-16s etc.

 

[Kompromat]

like i mentioned it before as well, those stains came from OIL drains, not Fuel drains.
Fuel system is a very complicated thing, but i assure you it doesn't work the way you suggested.

And this is a PT-04
you can see the flares are installed, or at least that yellow cap is gone.
It is odd why PAF still hasn't installed chaff/flares on it.

 

[razgriz19]

View attachment 24499

Sir ji, with all due respect I'm pretty sure its Photoshop
there is no place for flare dispenser on top of the fuselage.

unless you can prove me wrong other (which i hope, it would be good for jf-17)

 

[Kompromat]

Sir ji, with all due respect I'm pretty sure its Photoshop
there is no place for flare dispenser on top of the fuselage.

unless you can prove me wrong other (which i hope, it would be good for jf-17)

I was given this picture by someone credible. I am not sure if its photoshopped. The jet is descending which is why the flares look like being dispensed above.

 

[fjavaid]

Nice post but how did u get that picture ..... .....

There was a post some days ago about dirty belly of JF17. NOT leakage or bad quality... It is the venting of fuel out of these special vents you all can see in the picture I enclosed. Not everything goes away from the plane and sometimes it gets dried up in all those holes. I guess that if you spool down RD93 and the pumps are still on full speed then you could dump it through these vents. Just like many other planes. Just like many other fighter jet engines.


The yellow blocks are spaces where chaff flare is mounted. Not 100% sure cause haven't seen is sofar... The JF17 belly brakes are pretty obvious.

 

[Munir]

Nice post but how did u get that picture ..... .....

I pushed the button on the camera.

 

[Munir]

( I took this picture)
737-800 engine underbelly.
These drain holes are called case drains. Anything, be it fuel or oil, that leaks goes through here to atmosphere.
I clean these stains quite frequently.

The reason I said its most likely oil is because, turbine bearing are called labyrinth bearings, meaning they are sealed by the moving air. When the engine shuts down, oil is suppose to flow down so the scavenge pump can pick it up, however some of it drips inside the engine. Engineers decided to drain that oil to atmosphere, instead of sending it to the hot section or combustion chamber.

Fuel also comes out, You are correct. However its mostly oil that makes a mess (Jf-17 is an example)

I will try to take another picture of oil sitting inside the engine. Its not good for the engine, but its "normal" according to the mechanics where i work

I now understand what you mean. Ok let me alter my reply. In case of JF17 you do see those case drains as well. Just take my pic and you will those very small holes. The difference with your picture is that it does not have a extra flap on it to prevent wind going inside. In case of JF17 you do see those pipes sticking out. Those are linked directly to pumps that dump fuel in certain cases. These are not case drains. I hope you understand that military engines are beaten real hard so they must work under very different situations. So if they have to dump fuel to spool the engine down very very fast (and not let it flow back) then these pipes are perfectly suited for simple solution. I hope that answers some differences we had. Thanks!

 

[VelocuR]

Please don't post lousy Tejas pictures here, there is nothing to compare with them anyway.

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Can you see one screw is missing on the right side bottom corner?

 

[VCheng]

Please don't post lousy Tejas pictures here, there is nothing to compare with them anyway.

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Can you see one screw is missing on the right side bottom corner?

Rivet.

 

[HRK]

Ministry of Defence Production-Year Book 2012-13 (online published date 26-03-2014)
Page 49
On-going Specialist Projects

• Development of Universal Pylon for JF-17 aircraft

Page 50

• JF-17 Airframe Co-Production Project: Activities related to JF-17 airframe co-production project continued at a consistent pace during FY 2012-13. TOT work for various co-production activities commenced during the year, while milestones of capability achievement for various activities were achieved. A wide range of surface treatment processes, heat treatment facilities, and auxiliary equipment have been commissioned and qualified for JF-17 production.

Page 51

• Avionics Production Factory (APF):It also produces Radar Warning Receivers and Identification of Friend and Foe system through a joint venture with M/s CEIEC of China (not sure it is specifically related with JF-17 or not)

Page 52

• Serial production of Audio Control Box (ACB) for Block II

• Indigenous tester for Light Warning System (LWS) has been developed for JF-17 aircraft

• APF acquired capability in deployment of different testers for JF-17 avionics i.e Avionics Integrated Maintenance Station (AIMS), Integrated Survivalable Recordable (ISR), Weapon Mission Management Computer (WMMC) and Electro Mechanical Management Computer (EMMC).

• Smart Weapons Avionics Integration capability acquired through standard II transfer of Technology (ToT) contract. (not sure it is specifically related with JF-17 or not)

Page 59

Page 69

Following projects completed successfully in 2012-13 by Dte MP (Air):-

• Audio Control Box for JF-17 A/C (Qty-6)

 

[farhan_9909]

So what is this project indus worth 25million dollars?

 

[HRK]

So what is this project indus worth 25million dollars?

might be referring about Indus Viper exercise .... held in 2013

 

[Munir]

Every design has it advantages. I think we can compare JF17 with LCA like F16 with Mirage 2000. But should we keep comparing them for the xth time? I mean some will say look at those huge actuators on LCA... Well, a delta need much bigger control surfaces to counter the huge wing. Look at the Gripen... But the J10 has much better solution etc etc... If you ask me. Let us skip it. LCA is not operational fighter and JF17 block 2 is a lot more different then we all think. My 2 cents. p.s. comparing form outside without same measurement is not handy.