In the current build, helicopters fitted with a laser DIRCM (Mi-28NM’s L370V28-5L, Ka-52, Z-10ME, and other DIRCM-equipped helis) are effectively immune to the IRIS-T SLM. Firing a full salvo of 8 IRIS-T SLM at a single DIRCM helicopter results in all 8 missiles being defeated by the jammer. The target cannot be killed by the IRIS-T at all — regardless of salvo size, range, or aspect — which makes IIR SPAA worthless against these helicopters and is balance-breaking. This contradicts real-world performance on two independent counts.
1. Seeker resistance to laser jamming. The IRIS-T uses a high-resolution imaging infrared (IIR) seeker with real-time image processing. Unlike reticle/spin-scan seekers, which track a single hot point and can be spoofed by a modulated IR/laser source, an imaging seeker resolves the whole scene on a 2D focal-plane array and uses image processing to reject localized interference. The manufacturer, Diehl Defence, explicitly states the IRIS-T’s IIR seeker renders countermeasures including blinding lasers ineffective. To actually blind a modern IIR focal-plane array you must saturate or damage a large fraction of its pixels — that requires laser-weapon-class irradiance, not the low-power, SWaP-constrained jammers helicopters carry, which are optimized against legacy reticle-seeker MANPADS. (The Vitebsk “invincibility” claims come from live fire against Igla-type reticle seekers, not IIR missiles.) Published engineering analysis (SPIE) and NATO STO work both conclude imaging seekers are highly resistant to the laser-jamming techniques in question. The realistic effect of laser DIRCM on an IIR seeker is a reduced kill probability, not a guaranteed defeat.
2. Salvo saturation is physically impossible to counter at this scale. Even granting some degradation, a laser DIRCM must slew a narrow beam (the L370-5 jams within roughly a 7° cone) and hold it precisely on each incoming seeker. These helicopters carry only two jammer turrets, each with a limited field of regard. Two turrets cannot simultaneously hold a blinding beam on eight separate seekers arriving on the same axis. The current in-game result — 8/8 defeated — models the jammer as an omnidirectional, infinite-capacity device, which no real DIRCM is. Finite turret count, finite beam width, and finite slew rate mean real DIRCM is defeatable by salvo/volume fire and by engagement from aspects outside the jammer’s coverage.
Requested fix: model laser DIRCM as a probabilistic Pk-reduction system rather than binary IR immunity — a per-missile chance to break lock driven by beam-on-seeker dwell time, aspect, and range; a hard cap on how many simultaneous threats the two turrets can service; and no effect against missiles outside the jammer’s field of regard. This keeps DIRCM strong against single shots (the intended behavior) while making salvo fire and multi-axis engagement viable and restoring IIR SPAA as a counter.
Steps to reproduce:
- Take an IRIS-T SLM SPAA (test drive or Ground RB).
- Engage a DIRCM-equipped helicopter (Mi-28NM / Ka-52 / Z-10ME) within range.
- Fire a full 8-missile salvo at the single target.
- Observe all 8 missiles defeated by the DIRCM; the helicopter survives. Result is unchanged from any range or aspect.
Note re: prior ruling. This is aware of the earlier report closed as “intended” on the basis that laser IRCM is designed to blind IIR seekers. That ruling did not address (a) the IRIS-T manufacturer’s own published resistance spec, which directly speaks to laser jamming of this specific seeker, or (b) the salvo-saturation limit — a 2-turret jammer cannot service an 8-missile salvo regardless of per-missile effectiveness. Both points stand independently of the contested question of whether a single laser can degrade a single IIR seeker.
Sources
- Diehl Defence brochure (manufacturer spec on IIR laser-jam resistance): https://www.diehl.com/cms/files/Diehl_Defence_Broschüre2018_en.pdf
- Saab IRIS-T page / Army Recognition IRIS-T SL: the “rendering countermeasures, including blinding lasers, ineffective” line.
- SPIE — IR imaging seekers’ resistance to laser jamming:
https://spie.org/news/5614-ir-imaging-seekers-may-be-very-resistant-to-laser-jamming - NATO STO SCI-192, “Infrared Countermeasure Techniques Against Imaging Seekers.”
- Northrop Grumman AN/AAQ-24 DIRCM video — shows the single-beam, one-threat-at-a-time tracking mechanism (supports the saturation point).
- TWZ on the Mi-28NM L370V28-5L DIRCM, and Key.Aero on the L370-5 7° jamming cone / two-turret layout.
