Shenyang next gen combat aircraft thread

[enroger]

someone over at secretprojectsforum said the wingtips don't have any authority as they seem to be flapping around and not doing anything. I think the ailerons are rotating in the opposite direction to the wingtips to counter roll, so only yaw is induced which is hard to see, making it seem like the wingtips aren't doing anything.

We can safely ignore such remarks from spf or anywhere else for that matter. You're right though, AMW and aileron counter deflection produce pure yaw moment just like split rudder does. The fact they flap so rapidly does points to underdamping in control law like someone mentioned, if so it should be worked out in due time (it is also possible they're choosing a more conservative control law for the initial test flights for safety?)

 

[Nx4eu]

Each wingtip has an area of 2.25m^2 based on my measurements, assuming the length of the entire aircraft is 21m.

 

[Nx4eu]

Someone failed their aerodynamics 101 and it shows.

Not even aerodynamics, I'm trying to write a response and I just can't. Moment arms is high school physics, what a stupid statement. Those tiperons are generating a tremendous moment on the aircraft being positioned so far from the center of mass. The reason why they are flapping around so much is because the yaw moment generated only starts after a high deflection angle, while at all points of deflection it is generating a lot of roll force. Thus in order to stay stable at low speed the flight control system needs to rapidly move the surfaces in order to get yaw control while not rolling out of control. You can also see the ailerons are moving quite aggressively to compensate for the roll authority.

 

[secretprojects]

someone over at secretprojectsforum said the wingtips don't have any authority as they seem to be flapping around and not doing anything. I think the ailerons are rotating in the opposite direction to the wingtips to counter roll, so only yaw is induced which is hard to see, making it seem like the wingtips aren't doing anything.

Someone failed their aerodynamics 101 and it shows.

anyone can make an account on spf. that there are a few sme's within that community does not confer authority upon the entire community.
its not really worth anyone's while to laugh at the peanut gallery.

We can safely ignore such remarks from spf or anywhere else for that matter. You're right though, AMW and aileron counter deflection produce pure yaw moment just like split rudder does. The fact they flap so rapidly does points to underdamping in control law like someone mentioned, if so it should be worked out in due time (it is also possible they're choosing a more conservative control law for the initial test flights for safety?)

Not even aerodynamics, I'm trying to write a response and I just can't. Moment arms is high school physics, what a stupid statement. Those tiperons are generating a tremendous moment on the aircraft being positioned so far from the center of mass. The reason why they are flapping around so much is because the yaw moment generated only starts after a high deflection angle, while at all points of deflection it is generating a lot of roll force. Thus in order to stay stable at low speed the flight control system needs to rapidly move the surfaces in order to get yaw control while not rolling out of control. You can also see the ailerons are moving quite aggressively to compensate for the roll authority.

I mean, he did work as an engineer at Northrop for many years on various programs including the B-2 and YF-23.

What's your CV, guys? 100 hours in War Thunder?

 

[Tomboy]

I mean, he did work as an engineer at Northrop for many years on various programs including the B-2 and YF-23.

What's your CV, guys? 100 hours in War Thunder?

I think I'll trust the engineers at Shenyang to know what they're doing

 

[Nx4eu]

I mean, he did work as an engineer at Northrop for many years on various programs including the B-2 and YF-23.

What's your CV, guys?

Don't use authority to argue against my point. I don't work in the aerospace Industry, happy? Do you know if he was an electrical engineer, a mechanical engineer, a design engineer? Don't just quote that he worked on those programs.

I provided my own plausible analysis on what was going on in the video. He literally asked for other opinions, and questioned if a larger control surface is needed. I just find it pretty funny that he thinks that the control 'surfaces just alternating from left to right with no real authority'. I'm also open to any other explanations, please my ears are all open. I've admitted to mistakes before.

 

[enroger]

I mean, he did work as an engineer at Northrop for many years on various programs including the B-2 and YF-23.

What's your CV, guys? 100 hours in War Thunder?

Put aside the fact that anyone can claim to have any credential on the internet, you're just appealing to authority. I don't care who he is or who he worked for, I just judge him by his arguments and if they makes no sense they makes no sense. Simple as that

 

[Nx4eu]

I mean, he did work as an engineer at Northrop for many years on various programs including the B-2 and YF-23.

What's your CV, guys? 100 hours in War Thunder?

Would you like me to give you a frame by frame breakdown? So you can counter with better physics. I would love to learn from an aerospace expert. I'm not being sarcastic.

 

[Mearex]

interestingly at this moment in the video the right wingtip seems to be deflecting downwards which should cause the right wing to lift, making the aircraft roll to the left when it's rolled to the right. Perhaps it's trying to counter the right-rolling moment caused by the left wingtip deflecting downwards earlier in the video.

As cool as all moving wingtips look, it does take more work to induce a pure yaw moment compared to split air brakes like on the J-36 because split air brakes are symmetrical and don't induce roll. Makes you wonder why Shenyang chose the former. I'm also still hoping that its flat nozzles can have yaw TVC. That will truly be alien.

 

[secretprojects]

Don't use authority to argue against my point. I don't work in the aerospace Industry, happy? Do you know if he was an electrical engineer, a mechanical engineer, a design engineer? Don't just quote that he worked on those programs.

I provided my own plausible analysis on what was going on in the video. He literally asked for other opinions, and questioned if a larger control surface is needed. I just find it pretty funny that he thinks that the control 'surfaces just alternating from left to right with no real authority'. I'm also open to any other explanations, please my ears are all open. I've admitted to mistakes before.

I'm not saying his opinion on the matter must be correct because he worked at Northrop, but a whole load of people here are dogpiling on with very arrogant attitudes towards someone they don't know, when they probably have no measurable aeronautical knowledge of their own outside of what they read on the internet.