Ask anything Thread (Air Force)

Deino

Lieutenant General
Staff member
Super Moderator
Registered Member
What are the "pods" right behind the engines, like extended exhausts?

N992NA.jpg


I don't know, but why do you post this question in the PLAAF-section??
 

xyqq

Junior Member
Registered Member
What are the "pods" right behind the engines, like extended exhausts?

N992NA.jpg
Likely to suppress noises similar to a muffler, as NASA uses this jet to carry high-value instruments and passengers (e.g., astronauts). Interesting to see how close the SAR radar pod is to the ground.
ps. Did not see Deino's comment when this message was posted.
 
Last edited:

Xizor

Captain
Registered Member
Don't intent to muddy the relevant thread with a question. So...
What's the current status of WS-19 and WS-20.
Especially the WS-19, which seemingly gave off an aura of fast development and progress judging by the pictures posted last year. (with the team members standing under the testbed).
 

SpicySichuan

Senior Member
Registered Member
Just a quick question, does the PLAAF have air-launched stealthy standoff weapons similar to the Storm Shadow or the JASSM (500 km + range)? GB-6A? I mean ones light enough to be launched by J-10/J-16 fighters, not ALCMs like CJ-20.
 

The Observer

Junior Member
Registered Member
Out of curiosity, does anyone know what is the FOD standard for Chinese airbases? Is it closer to Western/Soviet standard?
 

The Observer

Junior Member
Registered Member
Does anyone know how designers decide a plane's pylon arrangement, especially fighter jets?

I noticed that starting around 3-4th gen, many fighters start having pylons on wingtips. However, there are some exceptions, most notably the F-14 & F-15, Mig-29 and its descendants, and J-10. The rest all seem to have some sort of pylon/pod on wingtips, so I'm curious about what does the planes that have wingtip pylon/pods trade in exchange for more store locations.
 

Bhurki

Junior Member
Registered Member
Does anyone know how designers decide a plane's pylon arrangement, especially fighter jets?

I noticed that starting around 3-4th gen, many fighters start having pylons on wingtips. However, there are some exceptions, most notably the F-14 & F-15, Mig-29 and its descendants, and J-10. The rest all seem to have some sort of pylon/pod on wingtips, so I'm curious about what does the planes that have wingtip pylon/pods trade in exchange for more store locations.
Pylons placement on wings is decided by internal wing structure capacity to hold loads at different joints/points at various conditions within flight envelope. Its a true mechanical structures problem and requires analysis on a lot of different factors.

Regarding wingtip pylons, these are generally used to attenuate wingtip vortices which increase induced drag.
 

The Observer

Junior Member
Registered Member
Pylons placement on wings is decided by internal wing structure capacity to hold loads at different joints/points at various conditions within flight envelope. Its a true mechanical structures problem and requires analysis on a lot of different factors.

Regarding wingtip pylons, these are generally used to attenuate wingtip vortices which increase induced drag.

Then is the reason J-10 is not equipped with wingtip pylon is that the internal wing structure is not designed for it? Also, is using wingtip pylon to attenuate wingtip vortices a nice bonus or an intentional feature?

P.s. now that you mention the wingtip vortices... Is Su-27/J-11 wingtip pylon designed differently to western wingtip pylon because the Russians noticed that added bonus and decided to design the pylon to strengthen the attenuation effect?
 

Bhurki

Junior Member
Registered Member
Then is the reason J-10 is not equipped with wingtip pylon is that the internal wing structure is not designed for it?
As i said, internal wing structure decides where your pylons under the wing will be, not necessarily the wingtips.
J-10 has a delta wing. This, in addition to the relative behaviour of leading and trailing wing section design, to a certain limit negates the wingtip effects that you see in conventional sweeped trailing edge wings like Su27. Gripen, for example still uses wingtip pylons to decrease the drag further( saab designers are crazy for efficiency), which allows it effectively supercruise under certain loads.
In commercial jets, wingtip vortices are countered with wing fins.
Also, is using wingtip pylon to attenuate wingtip vortices a nice bonus or an intentional feature?
Depends on how much your wing drag profile is weighted by the vortices.


Is Su-27/J-11 wingtip pylon designed differently to western wingtip pylon because the Russians noticed that added bonus and decided to design the pylon to strengthen that effect?
Any design characterisitcs has pros/cons.
Western jets like F15 have no wingtip pylons due to designers feeling it will add too much stability and inertia and effect its performance in a A-A scenario. It all depends on what performance characteristics you're trying to squeeze out of the airframe.
 
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