Abu Zolfiqar
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off-topic and i'm sorry; but i think one of those sukhoi crashes was attributed to a (major) pilot error
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the RD-93 being currently used is a modified derivative of the RD-33 used by the Migs
You wanna contest my post....may i suggest do so in a civilized manner with something to back your claim up as there is nothing offensive in my post.Coming back to your post The highlighted part is pure nonsense on your part and i will suggest to you is to go learn a few bits about modular designs and how JF-17 is benefiting from it before coming out and posting just for the sake of increasing posts. JF-17 would hardly need any modification to change from RD-93 to WS-13 why because PAF knew it could not continue with a Russian power plant for long because of the unreliability of the spares and has to replace it with a domestic version and JF-17 is designed keeping that in view. You are welcome to go through the JF-17 thread last couple of pages and you will see what i am talking about.
PS i am not mentioned anything related to the quality of the WS-13 so whether it has matured enough to be used on JF-17 or not has nothing to do with the fact that it can be installed on JF-17 without or little modifications.
Did u see the part about "jokes apart"
come on man, i thought YOU could take that joke !
anyway, here goes.
As far as modular design is concerned, things are hunky dory as far as design is concerned, but when it comes to putting the pieces together we have a problem called "integration".
Let me give you an example.
Assume that current JF-17 is using the russian engine.
The flight stabilization controls, engine mounts, fuel controls, etc etc are optimized for the same.
Now assume, taking those specs of the paper another engine is made, WS-13.
now firstly, it is next to impossible to make another engine with 100% same dimensional specs as the first one.
it is impossible to make another engine without causing structural modification in the fuselage.
even if the above are met,
The engines are same size, same weight,same bla bla bla,
it is impossible to have the engines of the same CG, also put in consideration what I said about lacking the fabrication skills and lacking metallurgical skills.
the posts in the thread, may lead the reader to assume that
in modular design, one can design this, and another can design that, and they will come together.
This is total rubbish, and readers should understand integration is achieved only after compromises.
I am career professional engineer, and do just this.
I back my arguments with field experience, not URLs.
However, I had point to mention. The F-16 is designed to be able to accomodate 2 different engines, one by GE and the other by PW. The F-16 was designed to accomodate either engine. Is that not feasible for the JF-17? My understanding is that the WS-13 was designed using the RD-93 as a baseline and meant to fit in the JF-17 from the start of design. Thanks!
Hi, I had one of my Mandarin speaking friends translate this article. I posted this on another discussion thread a while back. I am wondering if the WS-12 is actually the WS-13. Thanks!
ÊÀ½ç¾üÊÂÂÛ̳ - èÉÁú¡±Õ½»ú¹ú²úÐÂÐÄÔྐྵÓÐÃÀ¹úѪͳ£¿Í¼ z
The prototype of domestic-made engine WS12, which will be used in FC-1 (a.k.a. J-10), is reported to simulate US-made F404 instead of Russia-made RD93. After years of exploration, the thrust of this new engine can easily reach 95KN. It is also said that, with new materials used in FC-1, the thrust-ratio can achieve 1.05, which is comparative to the medium-sized battle planes of western countries. FC-1 with new engine can take off after 400 meters (roughly 1/4 miles) taxiing. The estimate of WS12 market is optimistic. Pakistani engineers have been involved in the entire process of manufacture improvement.
Did u see the part about "jokes apart"
come on man, i thought YOU could take that joke !
anyway, here goes.
As far as modular design is concerned, things are hunky dory as far as design is concerned, but when it comes to putting the pieces together we have a problem called "integration".
Let me give you an example.
Assume that current JF-17 is using the russian engine.
The flight stabilization controls, engine mounts, fuel controls, etc etc are optimized for the same.
Now assume, taking those specs of the paper another engine is made, WS-13.
now firstly, it is next to impossible to make another engine with 100% same dimensional specs as the first one.
it is impossible to make another engine without causing structural modification in the fuselage.
even if the above are met,
The engines are same size, same weight,same bla bla bla,
it is impossible to have the engines of the same CG, also put in consideration what I said about lacking the fabrication skills and lacking metallurgical skills.
the posts in the thread, may lead the reader to assume that
in modular design, one can design this, and another can design that, and they will come together.
This is total rubbish, and readers should understand integration is achieved only after compromises.
I am career professional engineer, and do just this.
I back my arguments with field experience, not URLs.
Boss,
that is the point,
the F-16 was DESIGNED to carry both, JF-17 was not.
Once the aircraft is designed to carry both engines
you can imagine that the engine developers had kept that in their mind and ensure that the engine can be replaced by the other one.
in this case we have a problem putting the Russian engine, we are running after the Ws-13 engine, which is not even fully mature, and over time it will have modifications before it is bullet proof and water tight.
Even if the WS-13 was intended to be RD-93's replica.
I can guarantee you,
even if you have the precise schematics of the RD-93,
even if the russians give you the alloy secrets
even if you have the same fabrication facilities
with all the even ifs
manufacture the same engine in China, and the product will be different from the original.
and integrating and debugging that is an even bigger pain in the @r$3.
so how can PAF/PAC bank on being able to just slapping it in ?
Now for IceCold:
See it this way
What do you call major modification ?
is it a structural change ?
is it concerned with moving equipment within the bay, to accommodate the new engine ?
do you refer changes to the fuselage design ?
All of the above are major changes in their own right, for the sake of the argument as imagine that these are all not the problem.
Just the re-work required in the control systems is bigger task than any one of the above changes.
I am not saying that it is impossible to put another engine in the air craft.
However I am saying it is difficult.
It will require a lot of changes and modifications.
and even when these changes are made, end of the day you will find out self to have made more compromises than any thing else.
Imagine this,
you have to move the mount point of the engine 6" for the new engine.
That is all, only 6 ", weight distribution is the same, every little detail is the same.
Now to make a new mount point, you will first remove the first one,
on the new mount point position, you will have to make the following:
1. Structural impact whereby you will have to study the stresses placed on the supporting fuselage. You will have to analyze take of, landing, super sonic, turns etc in account and simulate as much as possible to avoid experimentation.
2. Metal fatigue analysis: you will re-do all your calculations to analyze the ALL metal fatigue variables to make sure that this change will not cause an out of bound change any where else.
3. Vibration stabilization: This is EXTREMELY critical and it is self explanatory.
4. You will have to re-calibrate all your control systems to ensure your FBWs and rest work as they should.
the above 4 are just the some major tasks,
Now imagine you will have to do the above several times over to pass the quality cycles.
That is engineering for you ! and this is how meticulously a war machine is produced.
Actually the report says:
That means, it has 10% more than the actual RD 93 and by the specs that farhan_9909 posted for RD93, it would be 89,43kN afterburner thrust now.
You can't only include the higher thrust, but also have to add the 80Kg more weight of the WS 13 compared to RD93. Be it for more speed, or more payload, it must be a combination of less weight and more thrust.