Hacker News Reader

Comment by throwaway1492 | Hacker News Reader

Former US Army 19k here. Tanks are expensive to build, expensive to maintain, expensive to operate, hard to transport and require certain levels of infrastructure to operate in theater (bridges to support their weight). With current threats they are bound to become even heavier (and require more fuel).

While I am all for seeing the rise of Bolo's, and I love shock effect as much as the next enthusiast, the ability of a $500 drone with the equivalent of a RKG-3 grenade to take one out is really the only relevant part of the question. Tanks are dead.

https://en.wikipedia.org/wiki/RKG-3_anti-tank_grenade

https://en.wikipedia.org/wiki/Bolo_universe

Edit to add; "expensive to operate" was a bit of an understatement, the logistical support required for a tank company is tremendous, totally preposperous; 1000s of gallons of fuel a day, 3 types of ammo, support equipment and personnel.

View on HN

To paraphrase The Chieftan (who's video is linked elsewhere in this thread but I'll included here: https://www.youtube.com/watch?v=lI7T650RTT8 ), it's not about the tank's vulnerabilities, but the capabilities it provides that have yet to be provided elsewhere.

ATGMs, RPGs, guided mortar rounds and switchblade drones are not offensive weapons that can take and hold ground. But infantry, supported by a tank which they can knock on the hatch of and tell to obliterate the machine gun nest pinning them down with instant 120mm fire, can.

When armies find something that can replace the mobile, protected, and relatively instant firepower a tank can provide to the infantry, the tank will be dead. But nothing yet has quite come along to combine those things, and so regardless of the tank's vulnerabilities, it will remain.

Why do portable drones not offer the instant firepower?

If you're talking about DJI or equivalents they only have 30 minutes or so of flight time and can carry at most one bomb at a time. They can be useful in guerrilla situations but firepower wise it's not even in the same league as a tank with 40-60 cannon rounds and several thousand machine gun rounds.

What if the drone were so inexpensive and portable that you could consider it like you do ammunition? Then the flight time and payload is much less critical - it's just a pilot-able bomb.

What if we just donated that money to all these hostile countries' citizens, and told them we'd stop the donations if they piss us off? Instead of dreaming of turning the future warzone from Terminator 2 into a reality?

Well, that (economic intervention) has effectively happened to Russia. And yet they are still going it seems. So to answer your question: Nothing would happen, at least for a few months it seems.

It's easier for infantry to carry one drone and ammunitions than a set of one-shot drones.

In practice it’s actually the opposite. A reusable drone has to have enough fuel to come back, which halves its range compared to a loitering munition that doesn’t come back. A reusable drone isn’t intended to collide with the target, and can’t be rocket-powered, so it will be much slower to reach and strike a target when the target is identified. It has to have the ability to land and to be rearmed, which adds complexity and thus expense.

Past a certain size a drone can fly high enough and far enough that it fills the combat role of an aircraft, but as far as man-portable systems go, well-resourced militaries demonstrate consistent preference for single-use guided explosives like the Javelin or Switchblade to maximize range and payload size and minimize time to impact.

https://en.m.wikipedia.org/wiki/AeroVironment_Switchblade

https://en.m.wikipedia.org/wiki/FGM-148_Javelin

This is called a guided missile, or a loitering munition, depending mostly on how quickly it gets to the target. They’ve been around for a while and are very useful but have not rendered tanks obsolete yet.

They don't offer the same level of firepower. A portable drone may be faster employed than a helicopter, large drone, or close support aircraft, but it suffers from lack of payload. It also takes longer to get on target, and has it's own set of vulnerabilities. (The vulnerability argument being that even if it is expendable, a drone disrupted or shot down does not help your unit eliminate the threat it was facing.)

A large-caliber, direct-fire gun provides long range, precise, and instant effects. As The Chieftan explains: https://youtu.be/lI7T650RTT8?t=934 (timecode link provided.)

Because when a tank fires its APFSDS gun, the muzzle velocity is 1500 meters-per-second.

In contrast, a drone flies at 25 to 50 meters-per-second.

------

To put it in concrete terms, a tank 3000 meters away will hit its target in 2 seconds. A drone 3000 meters away will take 1.5 minutes.

In contrast, the Javelin you launch will take 12 seconds before it hits the tank at that range. That's more than enough time for the tank commander to see the Javelin and return fire, killing you before the Javelin even strikes the tank. (This is why "fire and forget" is so important on a missile like the Javelin). So we can see that even a missile like a Javelin has a significant speed disadvantage on these long-range plains that exist on the Donbas region. Its a different fight than the typical heavy-urban environment that Ukraine was doing well in a few months ago.

-----

Its one thing to fight a tank in urban combat, where they can only see 200 meters out (too many buildings blocking your vision and the tank's vision).

Its a totally different thing to fight a tank on open plains, where 3000m worth of vision is common.

> To put it in concrete terms, a tank 3000 meters away will hit its target in 2 seconds. A drone 3000 meters away will take 1.5 minutes.

> In contrast, the Javelin you launch will take 12 seconds before it hits the tank at that range.

What's the latency for the turret to pivot to the target angle? I suppose it's pretty fast but let's say in worst case 180deg? How long does that take? 1s? 10s?

T72 is about 3 seconds for 180 degrees. But it also takes time for a human in the tank to notice the incoming AT round, trace it back to the source, acquire a target lock, and then swing the turret over.

I can only guess at how long the full return fire process takes, but you only need to be pointing a javelin AT at the tank, it will do the rest. You can be sprinting away pretty much as you launch and get 50 meters away. Safe? Hell no, but it's not as bad as the "2 seconds" comment makes it out to be.

Only Javelin has that range, mind you.

NLAW has 1000m range. AT4 and Panzerfaust3 has 300m range.

If you are using an NLAW and the enemy tank has line of sight 3000 meters away, you are outgunned, outranged, and outmaneuvered and almost certainly will lose.

The tank has 40+ shots with a firing rate every 4 seconds. Javelin is a 50LB weapon that is single shot, so a miss (due to thermal smoke grenades / flares) is a critical mistake that will kill you.

Running away at 3km/hr only delays the inevitable, as the tank travels 50km/hr to close the distance with you... And had far more shots to invoke suppressing fire to scare you from running away effectively.

---------

The advanced weapons help, but a tank is a tank. It's faster than you, has more range than any weapon you can carry, is almost always decked out with the best night vision optics, has more bullets, bigger bullets, and armor to negate most of your weapons.

At best the advanced missiles even the odds. I'm not sure if I'd call it an advantage though, because of the single shot nature / long reload times of missiles / recoilless rifles, especially compared to tank guns.

That 2 seconds is the projectile. Unless you're already aimed directly at the AT firing point it's going to take more than 2 seconds for the tank to acquire a target lock and swing the turret into place.

Assume the turret is 90 degrees off target and it will take 2 seconds just to swing the turret around. Assuming it takes 2 seconds to notice the AT round fired, 2 seconds to target lock, that's still 8 seconds total for the tank shell to hit.

That's not great for the AT team, but it is a survivable amount of time for shoot-and-scoot tactics, enough that it's going to be a hellish war of attrition between armor & AT teams, not a completely one-sided battle. Which seems to be roughly what we're seeing in eastern Ukraine, unfortunately. A truly shitty and hellish situation all around.

> Assume the turret is 90 degrees off target and it will take 2 seconds just to swing the turret around. Assuming it takes 2 seconds to notice the AT round fired, 2 seconds to target lock, that's still 8 seconds total for the tank shell to hit.

That's a lot of "assumptions" that still leads to a virtual tie situation: both parties kill each other.

There's also the situation where the tank commander emerges out of hide-position, fires a shell, and kills the enemy infantry before they even know where the tank is, and the tank then retreats back into hide-position before any enemy even knows that a tank is there.

A tank in turret-down position is still exceptionally difficult to spot. And that tank commander looking out, waiting for the ideal time to ambush with his main tank gun, will have night-vision, thermal vision, and loads of other equipment.

See this screenshot of the Chieftan's discussion: https://imgur.com/tk10YHN.jpg

In "turret down" position, pretty much only the tank commander is visible. They can spot you 3000m away in this kind of position thanks to modern binoculars.

----------------

Given that the tank moves at 50km/hr, and has more expensive equipment (thermal vision / etc. etc.), the tank honestly has the advantage in most of these fights.

Infantry might (?) have the advantage of surprise and hiding. But tanks also might have that advantage. There's no guarantee that the infantry always ambush the tanks. Especially when you consider how much faster a tank travels, and the shear size / distance that these weapons cover (a tank can choose any point with 3000m line-of-sight to attack the enemy infantry, knowing that the infantry is too slow to keep up with the tank's movement).

I think the assumptions are reasonable, and if you hit the tank you may only have to survive that first shot of return fire.

Don't get me wrong, it's not ideal and the fighting is more about attrition than superior tactics. I agree completely that an open field is just about the worst place to deploy the AT system.Tanks may have to travel through open areas but they do so to get to & from locations of more strategic interest, and it's best to hit them in those places, or if enroute then at a location where there's a least more natural cover. And I don't think the tank is at all obsolete quite yet.

How much ammo can a drone carry? Even if its an African ... drone or a European one, it's a simple question of weight ratios.

Perhaps it could carry 5 — no, 3! — holy hand grenades.

I don't think the commodity drone approach is going to work very well against a competently-run military with electronic warfare capabilities the Russians seem not to be employing.

To defeat capable EW, you'd need self-directed swarms of drones, and we don't have those yet (especially not at Best Buy). I agree that remotely-piloted commodity drones would likely make a terrible mess of something like an African army with T-55s and not much else, and of course today's Russia (I never thought I'd write that sentence).

I concur on the cost of armor, but it comes with significant benefits, hence the investment we've made in logistics to support them. It's only preposterous when the situation makes it so, like a highly mobile island hopping campaign. They worked pretty well in Iraq. Twice.

Dropping an RKG-3 grenade on a tank from a cheap drone also requires that the tank be stopped -- something that happens far less often in a war of movement than in trench warfare. The war in Ukraine has been extraordinarily static (like the Nagorno-Karabakh War), and this has provided the opportunities for COTS drones to be useful in this way. A combined-arms offensive on a divisional or corps front might take a handful of losses this way, but it most certainly will not be stopped.

Drones or no drones, I'd rather be sitting behind 35cm of hardened steel than out in the open with maybe 2cm of body armor max.

RPGs have existed for along time. How does using a drone to deliver the grenade instead of a rocket really change the scenario?

Would you rather take on a tank with an RPG in hand, or be safe in a bunker and remote control your attack?

If you made a misstake in the first scenario, there is no second try. But if you have a second drone, there is.

(ukraine has more men than drones, though)

Drones are slow and not heavily armored. It seems like a shot gun would be good enough to take them down before they got close enough to hurt your tank. While they are doing a good job now it wouldn't surprise me if anti drone counter measures are easy\quick to develop.

The "shock" part of "shock effect" is kind of diminished if you can hide miles away from tanks, completely safe, and neuter them.

A munition that doesn’t have to come back is always going to have more range and be able to carry more payload weight than one that does have to come back afterward.

The Trophy Weapon System can intercept and defeat anti-tank missiles and grenades and has been proven in combat. Both US and Israeli tanks have those mounted on them. I wouldn't be so quick to dismiss tanks as dead. Just older tanks without active countermeasures are dead.

Those active countermeasures can be fitted to lighter armoured cars or self-propelled guns. At some point the costs of carrying 50 tonnes of passive armour outweigh the benefits.

What about drone tanks?

Reply on news.ycombinator.com