AL-31FP/Su 30 MKI : 3D TVC or enhanced 2D TVC?

Me and cw were having this discussion on whether the AL-31FP engine nozzles on the Su30 MKI provide true 3D TVC or 2D TVC.
Initially I believed it to be true 3D TVC and cw thought otherwise.
Although now I feel that it may not be true 3D TVC afterall, but an enhanced 2D TVC (still more than that of the F-22).

The last few posts of the thread below provide info on our discussions..

Last 5 posts

MKI doesn't have full fledged true 3D TVC. It has virtual 2D TVC ability by the canting of the nozzles outward in conjunction with specific thrust settings and positions, which are controlled by onboard computers, give it hypermanoverability.

There is speculation that an early test version may have had 3D TVC, but aside from speculation, current production Su-30MKI models only have 2D TVC capability with engines that can give a 'sort of' 3D TVC thrust-vectoring effect.

Read here under the Indian Su-30 MKI's, images included:

The Su-30MKI is powered by the Al-31FP (P for povorotnoye meaning "movable"), which is a development of the Al-37FU (seen in the Su-37 Terminator).

AL-31FP which is designed by the Lyulka Engine Design Bureau (NPO Saturn) is also different from Al-31F (by the same company). The Al-31F is the 'baseline' powerplant found in most Su-27 and its variants, and perhaps in the China's J-10 in the future and lacks TVC. The AL-31FP was only 110Kg heavier and 0.4 m longer than the AL-31F, while the thrust remains the same. Planes equipped with AL-31F can be upgraded to AL-31FP later on without any changes in the airframe. It is being produced now at the Saturn manufacturing facility at Ufa, Russia.

The Al-37FU (FU stands for forsazh-upravlaemoye-sopo or "afterburning-articulating/steerable-nozzle") basically added 2D Thrust Vectoring Control (TVC) Nozzles to the Al-31F. 2D TVC means that the Nozzles can be directed/pointed in 2 axis or directions - up or down. TVC obviuosly makes an aircraft much more maneuverable. Al-31FP builds on the Al-37FU with the capability to vector in 2 planes i.e. thrust can be directed side-ways also. The nozzles of the MKI are capable of deflecting 32 degrees in the horizontal plane and 15 degrees in the vertical plane. This is done by angling them inwards by 15 degrees inwards, which produces a cork-screw effect and thus enhancing the turning capability of the aircraft.

Su-30MKI Complete info
RUSSIA HOPES TO SELL THE ADVANCED VECTOR-PROPELLED ENGINE TO CHINA.





seekerof

[edit on 20-3-2006 by Seekerof]

Originally posted by Seekerof

There is speculation that an early test version may have had 3D TVC, but aside from speculation, current production Su-30MKI models only have 2D TVC capability with engines that can give a 'sort of' 3D TVC thrust-vectoring effect.


seekerof

[edit on 20-3-2006 by Seekerof]

That I read in some forum. So even if it is true one wonders why the early models HAD 3D TVC while the later ones didn't? Was enhanced 2D TVC almost as effective?
Where is the true 3D TVC? The MiG-29/35 SMT? RD-33?!!

This bit of credible information suggests:

Only research aircraft are known to have tested 3D nozzle technology so far...

Axisymmetric & Thrust Vectoring Nozzles

This would include the Russians who only have experimental research aircraft with 3D TVC, such as the MiG-29OVT and Su-37. The US has the F-15 ACTIVE, etc.






seekerof

[edit on 20-3-2006 by Seekerof]

Originally posted by Daedalus3
That I read in some forum. So even if it is true one wonders why the early models HAD 3D TVC while the later ones didn't? Was enhanced 2D TVC almost as effective?

The reason for this was the MKI was never tested with a 3D TVC engine and that was speculation. 2D gives limited capability and the MKI just improves slightly on that. I think the Mongoose maneuver would be the best example as well as tailslides. Cobras only the abilty for a up and down movement while the mongoose lets you stop in mid air and turn around. Watch the video it gives a good example.

Like this
www.dfrc.nasa.gov...

Where is the true 3D TVC? The MiG-29/35 SMT? RD-33?!!

Here
www.aviapedia.com...

Mig-29OVT

Watch the engine move at the end

EDIT: I think this might be the Mig-29 video
www.patricksaviation.com...

[edit on 20-3-2006 by chinawhite]

Wrong links its this one

www.electronicaviation.com...

the TVC is amazing

Originally posted by chinawhite


The reason for this was the MKI was never tested with a 3D TVC engine and that was speculation. 2D gives limited capability and the MKI just improves slightly on that. I think the Mongoose maneuver would be the best example as well as tailslides. Cobras only the abilty for a up and down movement while the mongoose lets you stop in mid air and turn around. Watch the video it gives a good example.

Tailslides are possile w/o any TVC.
MiG-29A/B can do that. I've seen it live.
I think the F-15 can also.

But this mongoose thing is new to me. I've not been able to find any concerete info on it with superficial google searches.

A bit came up on the X-31 though:

Mongoose Manuever with the X-31


And this article claims that the mongoose is in 'response' to the 'cobra' manuever on a Su-27 which infact has no TVC.

In this 36-second clip we see the X-31 performing the "Mongoose maneuver," beginning in a tight left hand turn, then pulling the aircraft into a high-angle-of-attack stall/tail-stand maneuver in which the aircraft remains in the vertical for several seconds, then pushes over to resume normal flight. This maneuver is in response to the Sukoi SU-27 "Flanker" test pilot Victor Georgievich Pugachev's "Cobra maneuver" or "Pugachev's cobra," in which the aircraft, like the X-31, is stood on its tail to give the pilot a tactical advantage in air-to-air combat by essentially stopping and pointing the aircraft weapons toward the opponent.

Source

[edit on 25-3-2006 by Daedalus3]

Originally posted by Daedalus3
Tailslides are possile w/o any TVC.

I dont mean tailslides as in a tailslide but stopping and just turning in mid air. I think the turn was turning on a coin. Real close turns not just turning. I dont know what its called be im going to refer to them as a tail slide

Originally posted by Daedalus3
Mongoose Manuever with the X-31

I already posted this link

[edit on 25-3-2006 by chinawhite]

My bad .. Didn't see it when you posted it.

Hey I bumped this thread up because I caught this somewhere.
Isn't this a mongoose manuever by your/above mentioned definitions?

The bit right at the end after the vertical flip:

Video clip