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JF-17 Thunder Multirole Fighter [Thread 5]

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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?

These plates (it depends on the temperature or strength variables which kind of material is used) are riveted on the internal frame. There are a lot of extra rivets so sometimes a few get lose. They just drill them out and replace them with new ones. Doesn't matter much unless more then a few in line are missing. Nothing shocking.

Between the brakes you see an attachment area. Looks like the place to secure the plane when doing engine tests. It is the same area where the airbrakes are situated (so can hold tremendous pressure). This is the level I look at. Every purza. You can understand the design a lot better by just using some decent pictures. I am curious about the antenna... Anyone?
 
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Can you see one screw is missing on the right side bottom corner?
Yes, that is not good. The size, quantity, and spacing of fasteners are usually from calculations of stresses incurred by a panel based upon its size, shape, and location on the aircraft. We know plenty of stories of airliners that lost 'stuff' in flight due to errors in maintenance. But airliners do not perform maneuvers like fighters do, so if straight and level flight can remove inadequately secured panels and other 'stuff' on an airliner, a single missing fastener can cause a 'Class A Mishap', using USAF terminology to describe damages greater than one million dollars and/or loss of life, because of high physical stresses on the panel during rapid maneuvers.

This is a maintenance integrity issue and the unit's CO should take immediate corrective action. Wartime necessities may allow some latitude in letting fighters off the ground this way, but not in peacetime where vital military resources must be meticulously maintained so they can be ready for 'the real thing'.

These plates (it depends on the temperature or strength variables which kind of material is used) are riveted on the internal frame. There are a lot of extra rivets so sometimes a few get lose. They just drill them out and replace them with new ones. Doesn't matter much unless more then a few in line are missing. Nothing shocking.
Does not look to be semi-permanent rivets but removable fasteners, looking at the heads and the hole itself.

Something like this...

Aerospace Panel Fasteners & Captive Screws | Stanley Engineered Fastening

Each must be torqued to specs during installation.
 
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Yes, that is not good. The size, quantity, and spacing of fasteners are usually from calculations of stresses incurred by a panel based upon its size, shape, and location on the aircraft. We know plenty of stories of airliners that lost 'stuff' in flight due to errors in maintenance. But airliners do not perform maneuvers like fighters do, so if straight and level flight can remove inadequately secured panels and other 'stuff' on an airliner, a single missing fastener can cause a 'Class A Mishap', using USAF terminology to describe damages greater than one million dollars and/or loss of life, because of high physical stresses on the panel during rapid maneuvers.

This is a maintenance integrity issue and the unit's CO should take immediate corrective action. Wartime necessities may allow some latitude in letting fighters off the ground this way, but not in peacetime where vital military resources must be meticulously maintained so they can be ready for 'the real thing'.


Does not look to be semi-permanent rivets but removable fasteners, looking at the heads and the hole itself.

Something like this...

Aerospace Panel Fasteners & Captive Screws | Stanley Engineered Fastening

Each must be torqued to specs during installation.

Thank you. But there are differences between how safety is defined in civil or military planes. Besides that even cracks have certain allowable sizes before they are repaired. Take for example the F16 wingstations. The attachment rings in the wings have well defined crack levels. And you even have non visible damage which only can be found with NDT (non destructive testing) and even there you have certain allowable damage. I think since this plane design philosophy is working horse with simple and easy maintainable features there is less linkage a western style very strict maintenance regime.

Looking at the wear and tear on the panel this plane has flown some miles after the missing fastener.
 
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Thank you. But there are differences between how safety is defined in civil or military planes. Besides that even cracks have certain allowable sizes before they are repaired. Take for example the F16 wingstations. The attachment rings in the wings have well defined crack levels. And you even have non visible damage which only can be found with NDT (non destructive testing) and even there you have certain allowable damage. I think since this plane design philosophy is working horse with simple and easy maintainable features there is less linkage a western style very strict maintenance regime.

Looking at the wear and tear on the panel this plane has flown some miles after the missing fastener.
Each issue must be assessed on its own merits.

Here is an example of panel fasteners rules, according to Boeing...

737-300_panel_fasteners_rules_zps18667b19.jpg


The main points are:

- All fasteners must be in place if panel edge is directly into airstream.

- Corner fasteners must be installed and there must be at least 3 adjacent fasteners ON EACH SIDE of the corner fastener.

- If a panel side contains 8 or less fasteners, NO missing fasteners are allowed regardless of airstream direction.

The US military follows the same rules and I saw this when I was on the old F-111. For the avionics panels on my jets, -111 and -16, no missing fasteners allowed. For the -111, avionics panels are directly in front of the engine intakes.

Regarding the pic, we do not know the circumstance of that panel, but if the jet was allowed to fly that way and if I was the unit's CO, I would have the maintenance chief in front of my desk. Then I would ground the pilot for one month, dock his flight pay for that month, for missing that on his pre-flight walk around.
 
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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!

since I've never seen a working fighter jet engine, i'll take your words for it.
I just thought of it differently. And I assessed it just from my experience.
I learned something new today, thanks.
 
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since I've never seen a working fighter jet engine, i'll take your words for it.
I just thought of it differently. And I assessed it just from my experience.
I learned something new today, thanks.
I did not work with jet engines myself but did follow a few courses in the 90's... So now and then I can talk to those that do the job. I think posters like Gambit are more on the job then I am. ;) This about JF17 is what I learned from the engineers when I made those pics. But the fun part is that in Le Bourget people thought I was representing Klimov/Catic when I informed them about JF17. There is a difference in reading everything on the net or getting in touch with the engineers.
 
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All things considered, maintenance in PAF has had its bad apples as well. From wrong screws/fastners going into an F-16 that led to an airframe loss.. to wiring control surface powers incorrectly that had aircraft disintegrating in mid air. All due to the idea of "letting it be".. or "doing with what is available".

Such attitudes have already led to the loss of multiple airframes in the past.. and will continue to do so. Wont be surprised if we lose another JF-17 due to some enlisted deciding to make do with whatever he has and skipping a step to get a jet airborne.. and the supervising officer accepting it so that he does not have to face the CO for telling him a jet cant go out that day.
 
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All things considered, maintenance in PAF has had its bad apples as well. From wrong screws/fastners going into an F-16 that led to an airframe loss.. to wiring control surface powers incorrectly that had aircraft disintegrating in mid air. All due to the idea of "letting it be".. or "doing with what is available".

Such attitudes have already led to the loss of multiple airframes in the past.. and will continue to do so. Wont be surprised if we lose another JF-17 due to some enlisted deciding to make do with whatever he has and skipping a step to get a jet airborne.. and the supervising officer accepting it so that he does not have to face the CO for telling him a jet cant go out that day.

I do not think I will reply that in depth. Maybe defend it that these things happen everywhere and it is related to stupidity to not able to counter the CO. The big issue is that the courage to say no is something that is not allowed. Here in the west you do not cross that line easily. There you have an extremely hierarchy and the society is just the same. It is a military system. But they should indeed move towards more based on knowledge or solutions instead of rank. There is more potential then doing it this way. The ground crew should get the same chances to raise in rank. You need flexible and smart engineering.

That is what I feel should be done. Pilots are nice but in the end the have their shortcomings because they have been pilots and not maintenance or engineers. It is the same mistake when trying to enter commercial market by PAC. You need to move away and get a leading man that knows how to run a firm and handle commercial markets. Just putting another senior ex pilot is just showing that you do not understand the environment. Flying planes is not the same as running commercial firms. This is one of the shortcomings when it comes to marketing JF17. If you look at Israeli firms... They do not put 5 pilots in a row to answer questions of civil visitors... You need a marketing team. And you do not need to hide everything from visitors. JF17 is nice but it is not high end and super secret. If you say nothing no one will buy it.

But to be honest. We do have many good pilots and superb engineers. They can achieve a lot with minimum.

I agree that the Indians are even worser in marketing but one should look at top 5 and not low 5...
 
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I do not think I will reply that in depth. Maybe defend it that these things happen everywhere and it is related to stupidity to not able to counter the CO. The big issue is that the courage to say no is something that is not allowed. Here in the west you do not cross that line easily. There you have an extremely hierarchy and the society is just the same. It is a military system. But they should indeed move towards more based on knowledge or solutions instead of rank. There is more potential then doing it this way. The ground crew should get the same chances to raise in rank. You need flexible and smart engineering.

That is what I feel should be done. Pilots are nice but in the end the have their shortcomings because they have been pilots and not maintenance or engineers. It is the same mistake when trying to enter commercial market by PAC. You need to move away and get a leading man that knows how to run a firm and handle commercial markets. Just putting another senior ex pilot is just showing that you do not understand the environment. Flying planes is not the same as running commercial firms. This is one of the shortcomings when it comes to marketing JF17. If you look at Israeli firms... They do not put 5 pilots in a row to answer questions of civil visitors... You need a marketing team. And you do not need to hide everything from visitors. JF17 is nice but it is not high end and super secret. If you say nothing no one will buy it.

But to be honest. We do have many good pilots and superb engineers. They can achieve a lot with minimum.

I agree that the Indians are even worser in marketing but one should look at top 5 and not low 5...

One could go on as to why the mentality of " We can handle it all" exists in the Pak Mil. Rather than admitting that there are many things they simply are not good at. Just because PAC has heard of marketing as a term, does not mean getting a few offcrs together will come up with a marketing plan. There ARE various firms in Pakistan who can perform the Marketing task quite well.
The social issues have to end, otherwise the society will never come out of this rut. Examples can be found on ACdre Tufails blog on how enlisted personnel are a lot more trained ,confident and trusted to perform tasks in the routine.

Similarly, even if it is the business of the PAF to know everything and anything about its equipment.. it would serve it well to have a second opinion on it for further improvement. Case in point: The Emergency Staff at a US(or UK) Hospital improved their response time for a critical patient from 7 minutes down to 1 min 30 sec thanks to assistance from an advisor for a F1 pit crew. He helped apply the same team and time management principles critical for a pit crew to service a F1 car on the race track clock to a hospital... increasing the chances to save more lives by over 50%. Think how similar advice to an Arming pit crew or maintenance crew in the PAF would increase turn around time for an aircraft during wartime.
 
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@Oscar Any update on the coolant related issue with the prospective AESA on the JF-17? From what we here we at least are in a rut since we're going it alone, again!
 
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@Oscar Any update on the coolant related issue with the prospective AESA on the JF-17? From what we here we at least are in a rut since we're going it alone, again!

Most probably in cold storage for now. PAF is busy in maturing current platform (see the quoted post) and chinese are busy in mating AESA to J-10 B and J-11 platform. Chinese are not interested in JF-17 AESA and PAF are not in hurry to get AESA. As per JF-17 project director. A realistic estimate of AESA integration in JF-17 would be 2016-2017

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

View attachment 24563
Page 69

Following projects completed successfully in 2012-13 by Dte MP (Air):-
  • Audio Control Box for JF-17 A/C (Qty-6)
 
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