RIO help - Supporting a sparrow vs a Notching bandit

[MeRLiNttu]

In my practice, the AI will execute a perfect notch vs sparrow shots, typically combined with a diving turn. This breaks my lock most of the time and trashes the Missile.

 

I understand this is a weakness of PD - but what are some RIO techniques or Pilot tactics to help babysit your sparrow shots from a bandit turning to the notch?

 

An example:

I am in STT at 12 miles and have just Fox 1. I see the bandits Vc rapidly decreasing -

 

Do I go pulse?

Do we turn into him?

Do we dive beneath him and turn off MLC?

 

Anyone having success?

Thanks

[Longiron]

Pulse cannot be notched

But easy to spoof with chaff

AFAIK

 

Reduce the chance of the sparrow going for chaff, set aspect switch to nose.

Edited April 23, 2019 by Longiron

[MRaza]

I've been told that in real life, you cant switch between radar modes once a missile has been launched. This isn't implemented in DCS right now but at least in real life, switching to P-STT would not be an option because the missile is tuned to a specific frequency before launch (or something like that).

 

With that said, when firing AIM-7s, I see no benefit in using PD-STT over P-STT other than a slight increase in range. To me, the risk of being notched and wasting a missile is too big when using PD-STT, so personally I would use P-STT for AIM-7s.

 

(Also, what's MLC?)

[viper2097]

Maybe this thread would be the right spot for that discussion?

Unfortunately, it got hijacked due an Aim-9 discussion, but you could bring it back on the rails if you want...

https://forums.eagle.ru/showthread.php?t=239053

 

Pd or P is depending on pore things. When in generally said that P can't be notched and also works with 0-speed difference, you need also to say that P mostly immediately looses the lock when it goes down due to ground clutter.

[Moafuleum]

So the answer is: try to stay below the bandit and use P STT?

[Whisper]

(Also, what's MLC?)

 

Main Lobe Clutter.

In case this helps :

There are 2 filters used on the return signal of a Pulse Doppler radar : Filter for Main Lobe Clutter and filter for Side Lobe Clutter. Both are there to eliminate return from the ground.

The MLC filters is used to eliminate the return of the ground from the pulse sent in the front, the actual wave used for detection. It's tuned at the frequency shift corresponding to a zero ground speed, and is responsible for the sensibility of PD mode to notching, since a notching plane has zero ground speed relative to detecting airplane and is filtered out by this filter.

You don't need this filter if none of your main signal is going in direction of ground, which happens mainly when you aim upward, thus when you're below your target.

This filter is automatically disabled when the radar signal is tilted more than 3° upward if I'm not mistaken. You can make sure it's disabled via a switch in RIO cockpit on the front left panel, I think.

 

The Side Lobe Clutter filter is used for the residual signal (way weaker than main lobe signal) sent downward toward the ground with an horizontal speed component equal to aircraft speed. That signal is reflected by ground and comes back to the radar sensor (since it has same horizontal speed, it "follows" the emitting airplane). Since it has horizontal speed equal to aircraft speed, its frequency is shifted by an amount corresponding to airplane speed. To avoid detecting a ghost target that woud be flying constantly at your speed, this frequency shift is filtered out. This explains why actual airplanes in front of you, cold, at your speed, are undetected, they are filtered out by Side Lobe Clutter filter. This one cannot be switched off, AFAIK, though it could be disabled at a certain altitude, I'd say, since the return of the residual downward signal should really be negligible when flying high.

 

 

Back on the original question, both Pulse and Pulse Doppler modes are prone to issues with ground return.

The first one is susceptible to losing target in ground no matter its aspect, whenever target is roughly close to ground (or more precisely, when some ground in the main lobe is at equal distance from the emitting airplane than its target, which happens quite often), the latter is susceptible to notching in ground return.

I don't know which one would be the most efficient between a P-STT lock and a PD-STT lock with MLC off, but both case kinda require you to keep out of ground return, so I'd say the most important thing to do would be to keep UNDER your target post launch.

[Karon]

Have you asked the same question this morning on r/hoggit as well?

 

Locking a notching AI target with Pulse is usually quite easy. It's a bit more difficult vs human pilots because they generally use the terrain for masking much better.

I don't understand why you would disable the MLC when your_alt < tgt_alt since it's probably disabled already (check the manual for details). Disabling MLC can work but in a look-down situation is not ideal although I haven't done many tests since Pulse is so easy to use. As the manual says, the AWG-9 is basically un-notchable in a look-up situation so manoeuvre accordingly if possible.

 

If the range in decreasing into WVR I had good results by using both P modes and TCS to maintain the initiative and defeat a target that was notching the PD (one or two episodes should be in my Georgia at War streams IIRC). Check the manual for more details about the TCS and its functions. It's a really neat tool.

[Eldur]

My usual experience with Jester is, while waiting to get close enough to get a safe shot:

 

"Switching to PSTT" (somewhere around 10nm)

"I've lost lock!" (immediately thereafter)

 

Something I've yet to understand probably...