Do ARH missiles not have all aspect seeker heads?

The last radar returns are from the chaff, not the plane? The game is simplistic in the modeling of this.

But how does a missile with only HPRF/MPRF lock onto chaff?

I didn’t say it was locked on the chaff, the last return was from the chaff although ambiguous, it could no longer see the plane. Last known aircraft position is roughly in the location of the chaff so the IOG will default there. Additionally, pulse doppler radars can lock onto the chaff if the cloud is large enough. I believe @InterFleet may be able to explain better.

But the missiles do not continue on an IOG path, they manuever into the chaff cloud, instead of maintaining intercept vector with the notching aircrafts last known direction.

Reread what I said. It is clear you are not understanding.

I don’t think I am explaining myself well enough. Here is an illustration of what I mean. The missile doesn’t seem to continue toward the last predicted intercept point via IOG, instead it seems to maneuver into the chaff cloud.

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Can you provide a video demonstrating the issue? Chances are the missile is indeed flying towards the chaff cloud, which is the last enemy position… not the previous point of impact. This is because as I said the missile is completely obstructed by the chaff cloud and can no longer see the target. It will fly for a certain amount of time towards the targets last known position and then drop the inertial guidance as it searches for the target again. Often times if this is in close quarters or final approach the target is already beyond the gimbal range of the missile and it will not find the track again.

i think what numba1 is trying to say is that IOG only takes into account the last known position but not the last known vector of the target.

That, or the missile is indeed locking onto chaffs at a certain point, which imo isn’t completely impossible, but i would have to recheck a tacview to be sure

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Aside from the fact that missiles can track chaff just as they would a beam aspect target - yes a tac view replay would be nice but he didn’t even provide an in-game example.

So I’ve looked at a few instances of it happening when I notch and chaff a missile, so far every time its because the missile has locked onto chaff. I’ll try to get a launch on a slow moving/notching target that isn’t dropping chaff and see what it looks like in tacview.

Tech mods have stated that the PD radars should not lock chaff under any circumstances, in which case you should make bug reports;

Make sure to include all necessary info;

On a flip side of this, Chaff is heavily overperforming in-game as it currently sits as well;

So missiles are not supposed to lock chaff?

Doppler (“Look Down” feature in radar/weapon card) radars (since Dec 2023) and doppler missile seekers (always) don’t have notch filter in track mode and can track targets by speed or/and range there.

This means that targets flying close enough to 90 degrees to the line-of-sight

  • in look-up cases are tracked well
  • in look-down cases can’t be tracked because of ground clutter (main lobe clutter)

If the target can’t be tracked the missile with IOG can use its last known position and speed to track and reacquire it.

If chaff is used

  • in look up cases it decoys the missile if the radial speed (notching target) or/and range (always) to the target and the chaff are close enough
  • in look down it doesn’t decoy the missile because ground clutter doesn’t allow seeker to “see” both target and the chaff.
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Is the clutter range gated at all?

Example
Launching Aircraft 11,000m Altitude
Target 1,000m Altitude

Looking down with a MPRF track, the target turns abeam to start the notch, is any of the clutter return rejected by range as there would be a good 1,000m of separation between the returns from the ground and the target aircraft.

Range ambiguity may not allow seeker to reject clutter using range gate.

In HPRF mode in I-band unambiguous range is 1-2 km, MLC spot is usually larger almost at any elevation so separation by range is impossible.

In MPRF mode in I-band unambiguous range is 7-15 km, MLC spot is larger if elevation angle (below the horizon) is small, but may be much smaller if elevation angle is large.

In the game in both MPRF and HPRF modes range ambiguity is not taken into account while processing ground clutter as it doesn’t help in HPRF at all and doesn’t help in MPRF in most cases.

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MLC (main lobe clutter) area in range
MLC length = Altitude / sin(elevation + beam width / 2) - Altitude / sin(elevation - beam width / 2)
Note that for aircraft radars beam width is much smaller (2.5-5 deg) than for missile seekers (12-15 deg).

Unambiguous range
Ru = c / PRF / 2

Pulse width (200-600 m) and range gate size (little wider than pulse width) also reduce space between the target and MLC in unambiguous range scale.

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Would this patent explain a method for reducing the effect of a notching target on a PD radar?

Also, I found these patents describing the method for an active radar homing missile to continue tracking a target through a beam/notch in ground clutter. Have you guys on the dev team seen these yet?

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What is important for us are well known abilities and limitations of real radars.

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Well these are patents from Hughes, when they were developing AIM-120C variants. I think there is a 0% chance you will ever come across unclassified/declassified documents detailing the actual capabilities of the seeker heads on the AIM-120s, so general descriptions of seeker logics and radar signal processing like these ones are probably the closest you will ever find to approximate the abilities of modern ARH missiles.

@k_stepanovich Speaking of that, firstly I appreciate that a while back you guys added the IFF indication in PDV mode for naval phantoms, but there are a few features that are still sorely needed, especially for simulator battles, where you use the radar not just for missile guidance but also for IFF. (Especially given that there are a lot of similar planes in all tech trees these days, making visual IFF quite unpractical).

Are there any plans to add these?

1- IFF in STT
This was reported and forwarded 2 years ago using F-14A documents (but obviously should apply to pretty much any plane):

F-14A Early: IFF stops working in STT mode

2- Keybind to toggle “Constant elevation of radar antenna” game option On & Off, and changing the option into pitch stabilization toggle

These days you pretty much have to turn off the “constant elevation of radar antenna” off and work the antenna elevation manually.
The issue is that with pitch stabilization always enabled (this option always turned off) it’s quite challenging to radar IFF people during close combat / dogfights as you and the enemy change elevation rapidly and frequently, so it’s more useful to have your radar pointed to an angle off your nose rather than an angle off horizon.

And in terms of realism, IRL virtually any aircraft that has pitch stabilization for its radar antenna (basically any aircraft with a half-decent radar set) (which allows to adjust and maintain the antenna elevation relative to horizon), can also turn the radar antenna’s pitch stabilization off (to be able to adjust and maintain the antenna elevation relative to the nose/axis of the aircraft).

For example, from F-4E Aircraft Aircrew Weapons Delivery Manual (NONNUCLEAR) - T.O 1F-4E-34-1-1 - 1979 change 1986, page 1-54 and page 1-55:

Spoiler

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