Coaxial machineguns are machineguns that point the same direction as a tank's (or IFV's) main gun. This makes aiming simple and the vehicle needs no additional means for training and elevation of the machinegun.

Coaxial machineguns use the mass of the turret for cooling and can be reloaded from under armour. Their biggest downside is that most coaxial machineguns allow burnt propellant gases to pollute the air within the turret, but that's an even bigger issue with the main gun, so ventilation is a must in crewed turrets. Coaxial machineguns have been common since the 1930's.

A special (and rare) kind of coaxial machineguns are retrofitted heavy calibre machineguns that are mounted outside of the turret.

You've very likely read about the threat of remotely-controlled flying drones to tanks. They're radio command-controlled and susceptible to jamming, but few tanks have such jammers. Netting is used to counter such drones, but purpose-built fuses would easily counter any such net.*


The answer to such drones is mostly jamming, though you may also shoot them down or burn them with lasers. Jamming can be done with quite simple means; you merely need power supply, a radio transmitter for the correct radio frequency band and a (directional) antenna that fits said band as well.

The whole package can be compact enough to be a one-man 'weapon'.


It's obvious that Western MBTs and IFVs are not prepared to deal with such a threat, and they are VERY vulnerable to it. We could equip them with jammers with omnidirectional antennas, but the permanent emissions by such antennas would be very easily triangulated and inform the enemy about tank locations and movements. We could switch such jammers on only when needed, but this requires the knowledge when they are needed; the detection of the drone.

You may use a weaker (or at same output power more effective) jammer with a directional antenna when you know where the drone threat is. So there's a case for directional drone jammers to be added to armoured fighting vehicles.

We already have quite a garden of antennae, cupolas, sensors and guns on top of tank turrets, though. A coaxial installation of a drone jammer antenna may thus be the way to go IF one decides against an omnidirectional antenna jammer. It may also make sense to have omnidirectional self-protection jammers and one tank or infantry fighting vehicle per platoon equipped with a longer-ranged directional jammer. The longer ranged one would be against observation drones, while the self-protection jammers would only affect the much more close attack drones.

I didn't write much about such jammers in the past because I consider remotely-piloted vehicles as a transitory thing. The really big deal will be drones with a degree of autonomy that allows them to do their job without an intact two-way datalink with a human operator.

My preference remains the use of mass-produced standardised remotely-controlled weapon stations (RCWS) on almost all battlefield vehicles (80+ % of the vehicles of a mechanised infantry brigade, for example). I hope we can make do without onboard search radars.



*: Drones with simple impact fuse can be countered, but a fuse can be built with an acceleration-measurement chip that sense the sudden deceleration when the drone gets caught by the net or cage and initiates the shaped charge explosion. The result would be a shaped charge attack with near-optimum standoff distance; even worse than a textbook impact fused shaped charge attack.


  1. To shoot down drones, guns need to be aimed with higher elevation. You also mentioned tanks with higher elevation for the main gun to serve as indirect fire artillery. Is this a trend of the future that guns are aimed all round at high elevation?
    Under such circumstances, does the thick frontal armour continue to make sense or will it be replaced by lighter all round armour and an increasingly indirect fire role?

    Drones depend on microchips and software. How well is Germany prepared in this field, in case war breaks out in East and Southeast Asia?

    1. I don't see any change in regard to maximum elevation of mass-produced AFVs' guns. Even RCWS don't seem to get built for +90° yet.

      Regarding AFV protection:
      Protection against single shot tank guns (calibres above 57 mm) seems unnecessary, because contact with hostile MBT is rare and you can be superior to a T-90 even with a protection against 14.5 mm (120 mm M829A4 coupled with superior ergonomics/communication/situational awareness/training/sensors/camo).
      We could even be satisfied with protection against 30x165 mm APFSDS.
      The protection against HEAT warheads is more interesting; passive/reactive against RPG-29 for crew compartment, cage vs. RPG-26 for engine compartment, hard kill APS vs. ATGMs, RCWS/jammer vs. RPVs & finally driver survives TM-62 hit with feet injuries would be satisfactory in Ukraine.

  2. Would you do as a thought experiment an analysis of a war between members of the global South versus the global North? Chinese and Russian propaganda and politics try to create such frontlines and on the propaganda level, they are highly successful. I doubt the Chinese succeed in creating a north versus south standoff and I doubt China's Belt and Road initiative will enable Eurasian and African armies to invade Europe in numbers anytime soon, but let's assume the connectivity is sufficiently improved to enable global clashes. I imagine that powers of the global South would be less loss averse and use cheaper technology, making them more numerous and cost effective than the gold plated and very loss averse small professional armies of the global North. Furthermore, the countries of the global South are less established as military powers, so might be more open to new techniques that are game changers, while our forces can be conservative beyond usefulness.

    1. 'global South vs. global North' may be a political-economic conflict, but hardly a military conflict. The geography doesn't permit it.
      Suppose Nigeria allies with Russia. Its military contribution couldn't be much more than sending troops by aircraft to Russia, but even that flight route would be a huge challenge. Would they fly across Central Africa, over the India Ocean, over Iran without being intercepted by carrier fighters over the India Ocean near Hormuz?
      And look at Egypt, new BRICS member; its military is heavily subsidised by the U.S.. Its senior officer corps won't be willing to ditch that sweet income. It's very likely heavily infested with CIA assets anyway.
      Ethiopia has also more to lose than to gain by opposing the West, especially once it has concluded its Tigray Civil War.

    2. I agree on the current difficulties, but let's imagine a build up of connecting infrastructure continues. How much more infrastructure would it need to interconnect these regions enough to wage a conflict?
      Such a conflict could happen in steps, securing resource supplies throughout Eurasia and Africa first, which would be local conflict from the new BRICS point of view. After securing an imbalance in raw materials supply, a build up for a next step directed against the global North could happen. I agree that the first step might be political-economic, but could turn into armed conflicts on local level. After securing an imbalance in resource access, the North-South direct clash that I consider possible can happen.

    3. They would need to be able to use sea lanes through the Atlantic or the Transsiberian railway needs to multiply (but then mostly Chinese strength would flow through it, not 'global south' strength.

      Moreover, NATO would simply introduce a tactical nuclear first strike doctrine if it truly becomes inferior in Europe.
      No air defence stops nuclear landmines.

    4. I see your point, I'm just not sure nuclear would happen. The crux of the looming war between great powers is that, unlike the Cold War, the threat of nuclear is less likely, making conventional war possible.
      Chinese strength might be less than what we think, making up in indoctrination for lack of resources. The Chinese GDP figures have been notoriously inflated and they are closer to 40% of what they claim with an economy the size of Japan and a shrinking population. India is rising and so far they have an ambiguous stance, taking all the benefits they can get, but eventually I imagine India to be decisive in such a confrontation.
      It's theoretical so far, because I can't imagine it happening now, but thank you for looking at this possibility of a confrontation. I agree that it's more likely to be an economic and political challenge for now. Still, if you could do some analysis what BRICS+ means, it would be great, because I think it's an important decision of countries to join in that union and I don't think we yet fully grasp the implications for us. Thank you.

    5. Let's first see how many decades it takes till this diverse and large group can agree on something important.