PAK-FA, T-50: News #2

Unfortunately, we got no other choice. But i´m still curious as hell.

That means you have to find something else to research, the LMFS maybe?

Current aircraft designs are limited by the pilot... small light aerobatic aircraft like the Su-26 can pull +26 gs and - 11 gs already.

To make a UAVs structure strong enough to take very high g forces is not that difficult and would not make them less aerodynamic, though it would effect the payload... pulling 30gs means a 105kg short range AAM suddenly weighs just over 3 tons and of course flying at low speed means it would not even be possible to pull high g turns.

the faster you move the higher the g to turn at a specific turn rate... moving at 5km/h it is impossible to pull 30g turns.

Large control surfaces would allow high g turns at high speeds.

I've heard between 12 and -10g, which is still very good. (It is a prop plane though, so at slow speeds they will always be maneuverable.)

Yeah, you just proved my point... The payload "pays the price" so to speak.

Yet another problem, maneuverability at low speeds it great, but either way a missile can outmaneuver it.

How large is the question... Then weight, aerodynamics and other factors become a problem.

I've heard between 12 and -10g, which is still very good. (It is a prop plane though, so at slow speeds they will always be maneuverable.)

No, that is the limits with a pilot on board.

They destruction tested it to see what its limits would be by putting weighs on the wings etc to test for strength limits to see when major components failed.

they have similar tests for airliners to see how far the wings will bend and what sort of weight they can support without breaking.

Onboard the Su-26? 

Test =/= real life aerodynamic capabilities. Modern jets typically can maneuver more than what they are rated (tested) at, so they can maneuver like that consistently and reliably. That doesn't mean they can maneuver like that in real flight.

Does Anyone have any information on the pak fa t 50 6/7 (static prototype) or the pak fa t 50 8?

I have spend Hours on research but haven't Found any usefulll info.

Gary B, do you have any insight?

I'm obviously not GarryB, but I haven't found anything more... It could be a while, so you might have to get used to the lack of news.

I don't have any inside information either.

The destruction testing of the Su-26 just shows that light strong aircraft can be built to take much higher stress than existing manned aircraft... currently missiles fired from artillery can withstand 100,000gs when fired... Just sayin'

Nice

Testing of weapons for the PAK FA will begin this year

GarryB wrote:I don't have any inside information either.

The destruction testing of the Su-26 just shows that light strong aircraft can be built to take much higher stress than existing manned aircraft... currently missiles fired from artillery can withstand 100,000gs when fired...  Just sayin'

 - I don't deny that, but keep in mind that the SU-26 is a sub-1000kg aircraft that can't hold any payload...

Really can't see anything exciting about Pak-fa ,its shape looks like an unfinished stealth plane and neither pretty its airframe...   bring on the stealth bomber..


A much better project will have been making a stealth version of the Swan Tu=160  or TU-22. with upgraded
radars ,sensors ,weapons and electronics.

Pa-fa is ugly ,even if is advanced ,fails to impress ,looks more like a cheap try of a stealth plane that they never
needed at all. And they have plans to sell it world wide , so it will be a matter of time it will be captured and
reverse engineered. Take a look at how amazing soviet designers made their planes.. and is a plane with much
more practical use that Pak-FA in real world conflicts.



Pak-Fa is not really needed plane at all.. Su-35 was more than good enough for air superiority. And is not like NATO was going to fly Stealth planes any day over Russia with S-400s and S-500s. Far more needed plane will have been A stealth super heavy bomber or a stealth version of Tu-22 or Tu-160 or a stealth Mig 31 or a stealth version of Su-34 that is much more important.. used to counter enemy air defenses.. Pak-Fa is a redundant plane .. specially when NATO will fly F-22s or F-35s over Russia. or near its air defenses range.

- I don't deny that, but keep in mind that the SU-26 is a sub-1000kg aircraft that can't hold any payload...

G rate is most significant for a high speed aircraft... the faster you go the more gs you pull for any given rate of turn.

For instance at 20km/h in a car you can spin the steering wheel around and turn 90 degrees without pulling anything like 10g.

An Su-26 was bench tested to 26 gs because it is probably not fast enough to get that sort of turn rate either.... but as you get faster and faster then pulling gs becomes easier and easier... a hypersonic fighter will either be a very straight flying manned aircraft or a moderately manouverable unmanned aircraft.

GarryB wrote:

- I don't deny that, but keep in mind that the SU-26 is a sub-1000kg aircraft that can't hold any payload...

G rate is most significant for a high speed aircraft... the faster you go the more gs you pull for any given rate of turn.

For instance at 20km/h in a car you can spin the steering wheel around and turn 90 degrees without pulling anything like 10g.

An Su-26 was bench tested to 26 gs because it is probably not fast enough to get that sort of turn rate either.... but as you get faster and faster then pulling gs becomes easier and easier... a hypersonic fighter will either be a very straight flying manned aircraft or a moderately manouverable unmanned aircraft.

That gets us to the argument of "does it even matter"... All you said is true, but the extra g's at high speeds won't provide the maneuvers capable at much lower speeds. Either way there are more important requirements of maneuvering, like losing little inertia, low wing loading etc.

That gets us to the argument of "does it even matter"... All you said is true, but the extra g's at high speeds won't provide the maneuvers capable at much lower speeds. Either way there are more important requirements of maneuvering, like losing little inertia, low wing loading etc.

You are missing my point.

Right now the MiG-25 and MiG-31 have a g limit of something like 4g at high speed because of its design. If it was designed from the start to be unmanned and not to be used for 30 years service then the g limits could be easily relaxed without any structural changes at all.

I am not talking about a low speed aircraft that can out manouver a very high speed aircraft, I am talking about a very high speed aircraft that is unmanned and can be built to out turn a low speed fighter or more specifically a super cruising F-22... imagine a mach 2.5-3 unmanned aircraft that can outturn a supercruising F-22 with a jammer and equipment on board to protect it from AMRAAM and AIM-9X... it wont need a payload of 10 tons of bombs... you could simply fit two nose mounted twin barrel 30mm cannon firing 3,000rpm each...


More importantly once it has shot down any F-22s near Russias border it can go around looking for strategic bombers and any cruise missiles they might have launched... linked into the VKKO system.

Mike E wrote:In order to maneuver at high-g's (12-15g), the aircraft has to be extremely aerodynamic,...

Wrong. Aerodynamics is about the STUDY of airflow over bodies.

When we casually say something like: 'The XYZ body is a very aerodynamic body.', it is meaningless. Airflow over it. So what ?

But if we say:'The XYZ body is more aerodynamic than the ABC body.', now we have frames of references. One body to compare against the other. The words 'more aerodynamic' mean airflow over XYZ body is more efficient than over ABC body.

More efficient.

Here is a clue for you: It is not the brick's main body that will allows it to fly, it is the flight control surfaces that will make the brick airborne.

If the flight control surfaces -- wings, rudders, stabilators -- are efficient enough, they will lift the brick off the ground.

A brick can pull as many g as propulsion and rate of change allows regardless of how inefficient airflow over its body.

havok wrote:
Here is a clue for you: It is not the brick's main body that will allows it to fly, it is the flight control surfaces that will make the brick airborne.

If the flight control surfaces -- wings, rudders, stabilators -- are efficient enough, they will lift the brick off the ground.

A brick can pull as many g as propulsion and rate of change allows regardless of how inefficient airflow over its body.

This is true. sooooooooooo in turn it will be structural limit. Or depend on what it carries.

If the flight control surfaces -- wings, rudders, stabilators -- are efficient enough, they will lift the brick off the ground.

Actually I would split those into lift devices (wings) and flight control surfaces (rudders, stabilators, aelerons etc).

the Lift devices will allow the brick to fly once lift exceeds the gravity force holding the brick down, where propulsion over comes drag and gives forward acceleration to flight speed.

The control surfaces allow a controlled takeoff and flight.

Control surfaces allowing varying turn and climb rates depending on how far they can deflect, how large an area they have and the speed of the airflow over them.

The MiG-25 has large control surfaces so despite its 4 g manouver limit it is actually very controllable at high speed.

havok wrote:

Mike E wrote:In order to maneuver at high-g's (12-15g), the aircraft has to be extremely aerodynamic,...

Wrong. Aerodynamics is about the STUDY of airflow over bodies.

When we casually say something like: 'The XYZ body is a very aerodynamic body.', it is meaningless. Airflow over it. So what ?

But if we say:'The XYZ body is more aerodynamic than the ABC body.', now we have frames of references. One body to compare against the other. The words 'more aerodynamic' mean airflow over XYZ body is more efficient than over ABC body.

More efficient.

Here is a clue for you: It is not the brick's main body that will allows it to fly, it is the flight control surfaces that will make the brick airborne.

If the flight control surfaces -- wings, rudders, stabilators -- are efficient enough, they will lift the brick off the ground.

A brick can pull as many g as propulsion and rate of change allows regardless of how inefficient airflow over its body.

You realize that I didn't try to define aerodynamics, right? In general, planes with more aerodynamic features (such as "lifting bodies", blended wings, "flatter designs"' and more control surfaces etc) will maneuver better than planes without them.

Never said otherwise.... You have to realize that without lift, and power control surfaces would do nothing to get an aircraft airborne. After all, they are *control surfaces*. Also, very rarely are control surfaces large enough to generate the required amount of lift, if it was otherwise planes would just use large amounts of canards and other surfaces to generate the needed lift. That is obviously not true. The early aircraft that couldn't fly had control surfaces, and they they didn't fly!

Yes, but once again, aerodynamics greatly help in that department. Notice how not a single jet is a "brick"?

Indo-Russian Jet Program Finally Moves Forward

Austin wrote:Indo-Russian Jet Program Finally Moves Forward

You made my week Austin. My vote

Austin wrote:Indo-Russian Jet Program Finally Moves Forward

Great! I was getting worried for a while there, but not anymore!

The Limits of Stealth

Great article, thanks for posting...