JF-17/FC-1 Fighter Aircraft thread

[Munir]

Re: New JF-17/FC-1 Fighter Aircraft thread

The plane is being verified under locally more extreme conditions. In the next few months they will finish weapon testing. They will do more advanced weapon testing next year (newer locally developed and western weapons). There is no need for mass pr if they will first use it as Pakistani plane. After more weapons and avionics are integrated the customers can select the different styles...

Besides that just imagine how many pilots are busy with the plane if they have 2 pre versions and after that almost a squadron... That is surely not slow speed testing. Besides that they are busy with ifr (published advertisement for engineers lang time ago!) and other add-ons.

 

[PakShaheen]

Re: New JF-17/FC-1 Fighter Aircraft thread

Thanks Munir for clearing up some things. I was little anxious as there is no new news in media about thunders since a while.

 

[Indianfighter]

Re: New JF-17/FC-1 Fighter Aircraft thread

Wrong. The JF-17 is indeed unstable in the pitch axis. When the first ever prototype was introduced, its flight control system was FBW on the pitch control, but retained manual on the roll axis. Later prototypes switched to FBW on the roll axis.

It may be true that JF-17 has FBW in the pitch-axis, but it does not necessarily translate to negative static stability. For this, aircraft are specifically designed to be so. Till date there have been rumors of of FBW only in 1 axis (pitch or yaw), but not 2 axes so is this a very recent development ? If it is, then testing may be prolonged as validations of FBW needs much longer than conventional controls.

 

[crobato]

Re: New JF-17/FC-1 Fighter Aircraft thread

It may be true that JF-17 has FBW in the pitch-axis, but it does not necessarily translate to negative static stability. For this, aircraft are specifically designed to be so. Till date there have been rumors of of FBW only in 1 axis (pitch or yaw), but not 2 axes so is this a very recent development ? If it is, then testing may be prolonged as validations of FBW needs much longer than conventional controls.

If the plane has pitch axis FBW from the start, its a good reason and a very high probability it has negative static instability. More so in the later versions because the redesigned LERX and DSI can cause such changes. The DSI may not be as sophisticated as the JSF's but certainly a lot more than conventional fixed and variable intakes you can find in aircraft today.

 

[Indianfighter]

Re: New JF-17/FC-1 Fighter Aircraft thread

Well, the new changes might have prompted instability but I think official confirmation could be awaited. Commercial airliners for example are not unstable, but have to have FBW.

 

[crobato]

Re: New JF-17/FC-1 Fighter Aircraft thread

Fighters are very different from airliners, so no comparison here. Just about every fighter and trainer in modern times that have FBW and LERXes have been pitch unstable. LERXes tend to move the center of lift forward of the center of gravity and that creates an unstable aircraft. The JF-17 has an aerodynamic layout similar to the F-16 and the latter versions of the JF-17 have more pronounced LERXes. And frankly I've read from Chinese sources that the plane is indeed negatively pitch unstable.

I think its in your court to prove the JF-17 is not unstable.

 

[PrOeLiTeZ]

Re: New JF-17/FC-1 Fighter Aircraft thread

extremely bad comparison between airliners and fighters, from all the chinese forums most agreed that it is indeed aerodynamically unstable.

 

[Indianfighter]

Re: New JF-17/FC-1 Fighter Aircraft thread

Fighters are very different from airliners, so no comparison here. Just about every fighter and trainer in modern times that have FBW and LERXes have been pitch unstable. LERXes tend to move the center of lift forward of the center of gravity and that creates an unstable aircraft. The JF-17 has an aerodynamic layout similar to the F-16 and the latter versions of the JF-17 have more pronounced LERXes. And frankly I've read from Chinese sources that the plane is indeed negatively pitch unstable.

I think its in your court to prove the JF-17 is not unstable.

It's true that combat aircraft that have FBW are usually unstable also, but that may not be an implication.

I still think that JF-17 is definitely not unstable, because otherwise there surely would have been official announcement by CAC or PAC. As another example contrary to what you said earlier, PAC says that it has FBW only in the pitch-axis and introducing it in the other axes is only a future plan. In the detailed interview of it's chief designer that tphuang posted a year or so back too, there is no mention of it. We only have Chinese internet's word for it.

 

[nemo]

Re: New JF-17/FC-1 Fighter Aircraft thread

It's true that combat aircraft that have FBW are usually unstable also, but that may not be an implication.

I still think that JF-17 is definitely not unstable, because otherwise there surely would have been official announcement by CAC or PAC. As another example contrary to what you said earlier, PAC says that it has FBW only in the pitch-axis and introducing it in the other axes is only a future plan. In the detailed interview of it's chief designer that tphuang posted a year or so back too, there is no mention of it. We only have Chinese internet's word for it.

Wrong -- here is an very official source.
What more do you need?:nono:

Please, Log in or Register to view URLs content!

5. New Designed Flight Control System

* JF-17 has composite flight control system comprising conventional controls with stability augmentation in roll and yaw axis and fly by wire in pitch axis.

 

[Chaminuka]

Re: New JF-17/FC-1 Fighter Aircraft thread

Number 107 of PAF - from from Air International, June 2008

Please, Log in or Register to view URLs content!

Please, Log in or Register to view URLs content!