The ATGM Threat Part 3: Solutions

I’ve previously posted about the history of antiarmor weapons and the current state-of-the-art.  The takeaway: tanks have never been invulnerable, and they don’t need to be.  Also, Anti-Tank Guided Missiles have become and are becoming longer-ranged, more accurate, and more lethal.  Despite improvements in ATGM technology over first-generation weapons like the AT-3 Sagger, American tactics have remained essentially unchanged for decades, although armor protection has improved.

The ATGM threat profile is a combination of standoff and high kill probability (per launch).  Remember, these don’t have to make ATGMs completely worthless, just make them less useful.  I’ll look at standoff first.

The Problem of Standoff

120mm tank rounds can comfortably engage dismounted ATGM teams at around 2km.  This is fine for medium ATGMs like the AT-13, but full-size systems have maximum ranges starting at 4km up to 8km.  5500m, the maximum range of the relatively common and modern AT-14 (Spriggan/Kornet), probably makes a better specified engagement range.

In order to grasp how serious the standoff problem is, consider the following:

A company of twelve tanks advances towards an enemy platoon of four AT-14 launchers.  The antitank gunners engage at 5000m with a 50% hit probability.  The missile takes about ten seconds to fly to the target, and another ten seconds to reload, giving us a salvo of four missiles and two hits every twenty seconds, or six hits per minute.  (This is a rather conservative estimate.  Hit probability will increase as the range closes, and a dedicated tank-destroyer vehicle might not even need to reload.)

The Kornet-D, a recently developed Russian ATGM carrier.

The tanks must cover three kilometers before they engage.  Moving at a very brisk cross-country pace of 40km/h, they will close the 3km standoff in four and a half minutes, while absorbing twenty-seven hits.

Perhaps you think I’m understating the range, and the tanks can engage at 3000 meters.  They’re tearing down an open highway at full throttle (60km/h).  In the two minutes it takes to close the standoff gap under these conditions, twelve hits.  If you think that your tank is invulnerable to frontal kills, I’ll repost this and you can tell me whether you think every hit will be frontal:

And there’s no reason for the enemy to cooperate.  For instance, if their launchers are vehicle mounted, they can drive away while reloading.

Indirect Fires

The most commonly-advised tactical solution to this problem consists of making contact with a reconnaissance element, then calling for indirect fire or air strikes.  Unfortunately, reconnaissance forces die just as easily (moreso, actually, since main battle tanks can plausibly survive a hit), and meanwhile an indirect fire mission takes at least two minutes.  Per enemy position.  Which are hopefully static, and not too deeply dug in.

There’s something to this, but unfortunately howitzer batteries just can’t respond quickly enough.  If clearing and firing the guns takes more than four minutes — which it often does — then the company might as well go for broke.  One method of mitigating ATGM standoff seen widely in the fighting in Ukraine (and somewhat in Syria) is to use self-propelled howitzers (especially the old 2S1 122mm tracks) in direct-lay.  These can throw a shell 6-8km, providing a base of fire as the shorter-range but more heavily armored main battle tanks move ahead.  The use of direct-lay means the guns don’t require forward observers or fire direction.

Two Turkish Leopard 2A4 tanks & a light vehicle destroyed near Al-Bab, Syria, 2016

The US doesn’t have a bunch of obsolete SPARTY tracks lying around (though the Paladin ought to be — a story for another day).  They do have 120mm mortars, however.  While these don’t have quite the range of the 2S1 (6800m fired from a track), they would allow at least some standoff.  One per tank company would provide be enough.

These tracks can already do their own fire direction.  Ideally, a tank would be able to call for fire digitally through its gun sight; right now only the company fire support officer in his specialized vehicle can do this.  This might be enough in the short term, since someone would have to prioritize incoming fire missions — most likely, the company commander would dictate or pass down organic indirect fire priority, and the FSO would actually choose which missions to fire based on these criteria unless countermanded.  The fire support team and the mortar crew would form a company fires cell.  This basically already occurs in cavalry troops; it should be extended to armor/mechanized line companies.

M1024 Heavy Mortar Carrier

Adding a 120mm indirect precision fires capability, especially if it extended range, would make this solution much more palatable.  Existing M395 GPS-guided rounds might work, though a laser-guided round would be better given the possibility of use against a maneuvering target.  A 120mm version of the Switchblade 60mm mortar-launched “kamikaze” UAS is another possibility.  The Strix autonomous homing antiarmor round might pose too serious a friendly-fire problem if fired over friendly armor.  None of these solutions require new technologies.

Extended Range

A brute force solution would be simply fielding an extended-range tank round.  The necessary precision would require guidance.  Eastern tanks have had guided rounds for years, and the Israelis developed the LAHAT for the 120mm smoothbore.  The US has repeatedly developed and cancelled guided tank rounds (STAFF, TERM, MRM) for the 120mm gun, so there does exist a knowledge and development base which would allow rapid fielding.

While the company-level indirect fire capability outlined above is a good idea, the American foot-dragging regarding extended-range, guided tank shells remains a mystery.  The LAHAT in particular looks to be a direct response to the increasing range and lethality of ATGMs.  Combat (including the 1991 Gulf War) has repeatedly demonstrated the value of standoff.  I chalk this up to a combination of fighting poorly equipped enemies, and a heavy reliance on air support.

Reducing Kill Probability

Closing standoff will do a great deal to mitigate the ATGM threat when the terrain looks like this:

But won’t be enough when fighting in this

where the problem is not standoff but kill probability.  And yes, tanks will continue to fight in cities.

America’s solution up to now has been: more armor.  We even, finally, started installing reactive armor (ERA) on tanks and Bradley IFVs.  Reactive armor has proven effective against ATGMs during fighting in the Ukraine.  It’s true that the latest, tandem-charge ATGM warheads have good results against ERA.  It’s also true that most ATGM (and short-range AT) weapons in national stockpiles are older, single-charge munitions.

One major obstacle to wide Abrams/Bradley ERA fielding is weight; the Abrams ERA kit (ARAT) weighs, IIRC, about seven tons.  With newer models already tipping the scales at over 70 tons (compared to the 62-ton baseline M1).  Indeed the SEPv3 upgrade removes armored side skirts for this reason.  Even then, ERA coverage pales compared to Russian counterparts (Bradley ERA has much higher coverage, since the vehicle’s own armor isn’t anywhere near as tough as the Abrams).  With the v3, the US Army will apparently do what it can to increase the number of tanks with some ERA.

TUSK Abrams with ERA on side skirts.

Reactive armor helps the vehicle survive when hit (again, easier than ever).  How to avoid getting hit?

Don’t Get Hit

Tanks already take cover or evade when under fire from ATGMs.  Unfortunately, tanks crews rarely know they’re under attack; they have limited visibility, and ATGMs have low launch signatures.

The easiest way to alert tank crews they’re under attack would be installing laser detectors (Laser Warning Receiver, LWR).  Some of the most dangerous (AT-14, most air-launched missiles) ride a laser beam all the way to their target.  Even when firing wire-guided missiles, crews usually use a laser rangefinder to check the range to the target before firing.  Of course, this also helps with tank-on-tank combat, given the de rigeur use of laser rangefinders in main gun fire control.

The detector doesn’t need to be foolproof.  Anything would be an improvement over what we have now: nothing.  Several competitor countries already install these on their fighting vehicles, and they are quite common in air and naval applications as well.   The detector would not only turn on a red light, it would characterize the incoming emission.  Steady illumination = guidance; momentary illumination = rangefinding.  Different equipment (say, an American or a Russian emitter) would have different emissions characteristics.  The LWR would provide a heading (though not target-quality data) as well.  The tank crew can then evade, take cover in terrain, return fire, or pop their smoke screen as necessary.

Unfortunately, a LWR can’t detect a missile in flight.  Other than the Mk 1 Eyeball — which doesn’t have a stellar record in this regard — the solution is Doppler radar, which detects objects and their velocity.  The latter allows the radar to discriminate against static or slow-moving objects like terrain and other vehicles.

Two Turkish Leopard 2A4s and a light vehicle destroyed by ATGMs in Syria, August 2016

Unlike a LWA, the radar would probably need to be linked to an automatically-deployed countermeasure, something that can actually stop (more correctly, reduce the probability of) the missile hitting the target.   The most dramatic countermeasure, “hard kill” active defense which actually destroys incoming munitions, is the holy grail (Active Protection System, APS).  Israel (Trophy) and Russia (Drozd, Arena) have already deployed these.  The use of fully autonomous passive-infrared homing (e.g. the Javelin missile) will eventually make this a must-have capability.  The soft alternative — aircraft-like flare dispensers — probably won’t be weight-effective, especially given the need to discriminate passive-IR guidance from other types.  The DoD has decided to install the Israeli Trophy APS on a third of its tanks in FY2019, so the United States will finally start closing this capabilities gap.

M1A2 SEPv3 with Trophy APS (turret sponson)

Even “soft” countermeasures such as jammers and automatically deployed smokescreens would provide an improvement over the current “nothing”.  Most modern ATGM launchers have a warning to indicate a jam, and the gunner can either wait until the jam clears or (on some types) fire using MCLOS guidance.  So, to maximize effectiveness, maintain emission discipline, and conserve vehicle power, a jammer ideally turns on only when a missile is in flight, hence the need for a Doppler radar to automatically detect a threat and activate the system.  The US installed a manually-activated jammer (Counter-Missile Device, CMD) on some Bradley IFVs at one point, but stopped after poor results in training (the crew had to observe an incoming round and face the turret towards it while turning on the CMD.)  As far as I know, this is the only such attempt to employ such as system on ground vehicles by the US.

T-90 with Shtora IR Jammer

Of the four countermeasures outlined above (reactive armor, laser warning, hard-kill, soft-kill), reactive armor is already fielded to some extent, and weight limitations will prevent the Abrams from being covered over with tiles.  Laser warning receivers could be deployed with relative ease.  Active countermeasures, soft or hard, take longer to develop.  However, these are a relatively mature technology.  I don’t have any special insight into development or acquisition, but the delays in development and fielding of these are inexcusable given the progress demonstrated overseas.

Conclusion

Heavy armor and telling crews to keep an eye out for smoke puffs won’t be enough to allow armored vehicles to survive against the development and proliferation of increasingly capable ATGMs.  Even relatively marginal fighting forces will increasingly employ these; the US experience employing armor against minimally-capable forces in Iraq and Afghanistan does not provide an effective picture of future threats.

The systems outlined above are all under development.  However, the US has not deployed them.  This must happen as quickly as possible, rather than waiting for immediate need, to train and familiarize crews with new systems and tactics.