Sukhoi Su-27/30/33/35/37 Flanker series & Su-34 Fullback - History, Design, Performance & Dissection (Part 3)

I kinda fw the grey.

Does anyone know what is it that TurkishAF F16 carrying in the center pylon? I see the TGP, other one is the some sort of ECM/ELINT pod perhaps?

The shape of the pod matches the AN/ALQ-131 but the F-16 is pretty far away it’s difficult to confirm

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I can’t think of anything else that matches the shape so closely, so yeah I would say AN/ALQ-131 too



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full thesis paper for development of n011m and n035 tracking algorithms, towards the end there is a flight test data of a n011m on a Su-30mki in 2003 and no35 on a su-35
M10250.zip (10.8 MB)

Some interesting notes, courtesy of ai for translation and summary:

Spoiler

1. Radar System

The radar described is an airborne multifunction radar designed for fighter aircraft.

According to the dissertation, its functions include:

  • Air target search
  • Ground target search
  • Sea target search
  • Target tracking
  • Missile guidance
  • Illumination of targets
  • Navigation
  • Terrain following
  • Weather mapping
  • Electronic reconnaissance

These are described as standard requirements for modern fighter radars.


2. Purpose of the Research

The main engineering problem was:

increase angle-measurement accuracy while expanding radar field of regard from approximately ±60° to approximately ±120°.

Traditional systems have:

  • Mechanical antenna
  • OR electronically steered phased array

Both have drawbacks.

The proposed solution combines:

  • Electronic beam steering
  • Mechanical antenna steering

into one tracking system.

The dissertation repeatedly calls this

combined beam control


3. Radar Type

The radar uses a

Passive Electronically Scanned Array (PESA)

(the Russian abbreviation ФАР).

The phased array is mounted on a two-axis hydraulic gimbal.

Advantages:

  • Instant electronic steering
  • Large mechanical field of regard
  • High tracking precision

4. Beam Steering

Instead of relying only on electronic steering:

Electronic steering:

  • tracks targets rapidly

Mechanical steering:

  • re-centers the antenna
  • stabilizes beam during aircraft maneuvers
  • allows tracking well off aircraft nose

The dissertation states this expands azimuth coverage to

±120°

and elevation to approximately

±60°


5. Radar Scan Limits

Electronic scan:

approximately

±60°

Mechanical steering:

adds another ±60°

Combined:

approximately

±120°

This allows nearly the entire forward hemisphere to be covered.


6. Radar Accuracy Parameters

The dissertation gives several engineering values.

Beam positioning accuracy

Approximately

4 arc minutes RMS


Beam steering resolution

1 arc minute


Beam switching time

Approximately

0.2–1 ms


Mechanical positioning accuracy

Hydraulic encoder accuracy

about

1.1 arc minutes


Total tracking error

Total RMS tracking error combines:

  • receiver noise
  • antenna quantization
  • inertial navigation error
  • hydraulic encoder error
  • target angular scintillation

The dissertation derives the total error statistically.


7. Radar Tracking

The tracking loop includes

  • beam stabilization
  • Kalman filtering
  • extrapolation
  • coordinate transformation
  • inertial navigation correction

The radar predicts target motion rather than simply following measured positions.

This reduces lag.


8. Kalman Filter

One of the dissertation’s major contributions is the use of a

modified Kalman filter

for angle tracking.

It compares:

  • α-β filters
  • modified Kalman filters

under

  • fighter maneuver
  • target maneuver
  • simultaneous maneuver

The Kalman filter consistently reduced tracking error.


9. Aircraft Motion Compensation

An important topic is compensating for

  • roll
  • pitch
  • yaw

using inertial navigation.

The dissertation notes that

errors and delays in the inertial system

become significant during high-G maneuvers.


10. Coordinate Systems

Three coordinate systems are used.

Aircraft coordinates

Fixed to aircraft.


Antenna coordinates

Fixed to radar.


Earth coordinates

Navigation frame.

Coordinate transformations are continuously performed between them.


11. Mechanical Drive

Hydraulic gimbal characteristics include

Azimuth:

±60°

Roll:

±120°

Step response:

about

0.25 s

Maximum slew:

approximately

60°/s

and

120°/s

depending on axis.


12. Radar Targets

The modeling includes

Aircraft

Missiles

Ships

Helicopters

Civil aircraft

Typical maneuver parameters are provided.


13. Tracking Errors Considered

The dissertation models:

Receiver noise

Angular scintillation

Aircraft motion

Gyroscope delay

Mechanical misalignment

Target maneuver

Atmospheric turbulence

Discrete update interval


14. Multi-target Tracking

The radar is intended to

simultaneously track

up to approximately

10 targets

while continuing search.

The beam rapidly jumps among tracked targets electronically.


15. Simulation Studies

Chapter 3 contains computer simulations investigating:

Fighter maneuvers

  • rolls
  • turns

Target maneuvers

  • weaving
  • turns
  • acceleration

Close air combat

Both aircraft maneuver simultaneously.

Metrics include:

  • RMS tracking error
  • dynamic tracking error
  • stability

16. Flight Testing

Chapter 4 is devoted to flight experiments. The table of contents identifies three major flight-test campaigns:

  1. Tracking stability during a fighter “barrel roll” maneuver, including the flight-test methodology, results, and conclusions.
  2. Angle-measurement accuracy at medium ranges, again with methodology, results, and conclusions.
  3. Accuracy during simultaneous fighter and target maneuvers, followed by conclusions from the flight experiments.

The introduction also explains that the work was validated through bench tests and flight-development tests of airborne radars operating against air and ground targets. It states that the methods and algorithms were used in development work for the Su-30MKI and Su-35E (Irbis) radar programs, and that the concepts were evaluated during state and factory flight testing between 2004 and 2009.


17. What the Flight-Test Data Shows

From the portions available:

The flight testing verifies:

  • Stable target tracking during aggressive aircraft maneuvers (including barrel rolls)
  • Accurate angle measurement at medium engagement ranges
  • Successful tracking while both the fighter and target maneuver
  • Agreement between the mathematical model and measured flight-test performance

The dissertation presents these results as validation of the combined mechanical/electronic beam-control concept, rather than as operational performance claims.

og doc is in russian, you have to OCR it if you don’t speak it

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George N confirms no N035 on SM2
image

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Was it George that was working at sukhoi/UAC?

Yes, George is the UAC engineer everyone on the Forums loves.

Here’s a link to his profile

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image

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what is even better

my message that i linked was in response to yours

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Now you just have to convince gaijin

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Getting off WT and going into greener pastures.

The Su-35S Mod has me intrigued.

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And for them to, effectively, kill the jet and make it slightly better than regular Su-30SM (because I’m damn sure that AL-41 are next on the chopping block)

Oh well, we still can hope for Su-35S to come and do it thing… right?

Irbis removal has been accepted for so long, gaijin takes ages to take action. Also it confirmed to be fitted with al41f

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AL-41F-1S is at least in testing, and according to the documentary new SM2 airframes are already produced with modified intakes and engine mounts to fit them in. In reality SM2 was never really needed in-game, regular SM was strong enough for the top tier.
Actually i am curious if new SM2s with dark radomes are fitted with AL-41s or not.

Fighterbomber complained that white radomes made Russian jets very noticeable in the sky if the weather is clear, up to tens of kilometers. Maybe that’s the reason why new SM2s use dark radiotransparent paint

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gets provided primary source informations
“Secondary sources are not accepted”
marks as not a bug

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wait and see they correct it in the same patch with new airframe to make people grind.