In double-checking things while posting this comment, I realize that I seem to have misunderstood the supply rules a bit. The supply amount listed for a unit is the amount for a full 10-round resupply, not the per-round usage. That means I overstated my supply usage above by a factor of 10. I also grossly oversupplied my units in the formation design post on page 10 that I was basing this on. I thought I was providing 13 rounds of fire for the formation, but I was actually providing 130 rounds. I'll want to adjust that substantially. (No wonder the supply requirements felt so onerous!)
That's... rather much. It
can work out that such a level of supply is necessary though, when a planet is very defensible. 130 rounds of combat works out to about a month of fighting (IIRC 1 round is 6 hours, if it's 3 hours is about 2.5 weeks of fighting), and I can see very well defended planets take that long to get the defenders ground down unless you go in with absolutely overwhelming force, and at that point you are basically committing a vast chunk of your GFTF production for an extended period of time.
For sure, but a BP advantage for the attacker is expected. The attacker is hitting one planet at a time, while the defender needs to garrison all their planets. Similarly, space-efficient attacking forces(even at the cost of more BP per unit of combat power) are entirely expected, because of the cost of building troop transports.
True, but at the same time the relative cheapness of stationing and
keeping troops in secured space is not to be neglected. This is not real life where regardless of engagement you are going to need to ship tons of material to a regiment every day just to keep the soldiers in fighting form. I mean, just a day ration (let's take the Humanitarian Day Ration as an example) weighs 850 grams and provides about 2200 calories. Soldiers burn between 4500 and 5000 calories per day, so let's say that's 2 ration packs at 1700 grams total and we'll fudge the difference.
The infantry regiment you used has 1595 individual units, and let us round it to 1600 people in a regiment (this is nonsense, the weapons teams and administrative staff would comprise of at least 100 people between them, and far more likely several hundred). With 2 ration packs per person you'd need to supply just the soldiers with at minimum 2.7 tons of food every day. And that's just food, we're not talking about munitions, spare parts, or fuel, all of which would by the way strictly speaking be abstracted away into the ground supply system, and you don't have to provide any supply until soldiers are in combat.
So, sure, the defender has to have a presence of some sort everywhere and probably can't afford to place as much BP density as the attacker on any given planet that could end up under attack. Given that the defender is likely to be at a naval disadvantage he probably also can't move the troops he does have as easily as the attacker. But at the same time, GFTF are production facilities with a defined amount of production capacity and if both the attacker and the defender have the same BP totals available for their armies, attacking and defending forces may well end up costing the same anyway, with only their relative concentrations differing.
Losses per round go up by about 70%. Everything gets twice as easy to hit, except the HQ, which is only 50% easier.
Of note - the math breaks down a bit here. The attacker is getting credit for 1.3 kills on the HQ per round, but of course there's only one HQ in the force. As a result, the loss cost is slightly overstated. Again, don't take these numbers too literally.
Of course, but it does show the importance for the defenders to dig in very deep.
My understanding is that they can be held behind the front lines, and mostly avoid combat that way. You're at risk of breakthroughs, but at that point you're already in trouble.
While true, it's relevant to note that bombardment and counterbattery fire are just as random as normal ground unit fire, only fighters flying Flak Suppression missions directly target a specific type of enemy formation. Because of this, having PWL infantry in the formation is just as effective at soaking bombardment fire and keeping valuable formations safe as they are at soaking fire from enemy breakthrough units.
Tagging relevant forces as combat avoidant just makes the PWL 500% as effective as they would normally be, because you wouldn't define them as combat avoidant, you want them to get shot at in such circumstances.
Changing the infantry defenders from 1 armour to 2 armour means they go from losing 36.83 BP/round to losing 40.19 BP/round. Losses fall substantially(from 87 units to 54 per round), but since the cost of all infantry has just doubled, the net effect is a bit detrimental. You save more forces for future rounds, though, so a more detailed multi-round model might show it being somewhat advantageous.
It'd probably be a good plan if your primary limitation is troop transport and not BP, though. Marines getting power armour looks like a good decision, and maybe also landing forces.
Iterative testing would be required here, yes. I would expect that the compounding effect of losing about 1/3rd less units is helpful, because that also means you lose 1/3rd less firepower over time. It's definitely something that will require a bit of thought though, because it also means that you are effectively bringing 1/2 the infantry to the fight on the same production budget. It's one of those 'we could equip everyone with 5 million credits worth of equipment and see them swarmed and torn apart, or we could equip everyone with 500 000 thousand credits worth of equipment and lose half of them and win anyway' cases.
It wouldn't be the first time where the numerically superior side wins on count of being numerically superior and having more guns to shoot, despite the enemy being better protected.
Interesting. This is a good point - my force was originally intended to work in mixed formations alongside armour units, but that means it's not expecting to do its own heavy lifting at anti-tank work. Yours is more balanced in this regard.
And sure enough, its performance improves a lot. Those AT emplacements do amazing work - each one costs 1.2 BP, and kills 6.75 BP per round. The sum total for the unit is that it'd take 22.85 BP per round of damage, and inflict 95.41 BP worth.
That's a pretty damn good trade.
I also rather like the front-line HAA because of a quirk in the rules - LAA is as good in the front line as anywhere(since it can only cover its own unit), and HAA is equally good anywhere(since it can shoot at anything), but MAA really wants to be in a supporting position so it can back up several subordinate units at once. HAA also makes a pretty good anti-tank gun on top of that, roughly comparable to MAV(though twice the size). For a real garrison force, I think this would be a reasonable choice. Back it up with some supporting STO weapon emplacements, of course.
More like such a formation would be the ground security complement for the STO emplacements. Those HAA units are rather expensive in supplies for an AT weapon, but the question of 'do I deploy them forward and risk them getting shot apart by ground forces early but deter enemy tanks' or 'do I keep them in the back so they can bully enemy airpower but get flattened in an instant in a breakthrough' is an entirely valid one that I expect will depend at least in part on what sort of enemy forces you are facing. I'd move them forward sooner with an enemy assault force with a large armour component.
Thank you for the info. That makes a bigger difference than you might expect. Instead of killing 37 BP/round, the attacker only kills 19 BP/round instead. The defender's HQ getting blown up was a huge part of the attacker's damage. The attacker's losses also drop, from 54 BP/round to 47 BP/round, but that's much less drastic. Using your garrison force, the updated values are it killing 86.99 BP/round and losing 19.89 BP/round, so roughly comparable ratios.
I'm also much more bullish on infantry logistics than I was previously. Your unit goes from losing 9/round to enemy fire down to 2/round, for example.
If you are losing logistics to enemy fire from non-breakthrough units it might be worth reconsidering forward deploying logistics units. Due to how logistics work they are always at risk, and the highest logistics unit in the planetary OOB gets drained first anyway. It might work out better to have a small(ish) vehicular logistics unit attached to the force but separate and kept in the rear, where it's not as likely to get flattened during the fighting unless the battle is lost anyway.
Because in any fight where that garrison force is part of a higher command with vehicle supply units on hand, supply integrated in any formation that is likely to take fire is going to be lost supply. So you wouldn't want to put infantry supply forces forward anyway except when your forces have drained their supply pool and need a top up, which is just a micromanagement hell issue, and you want to keep your logistics vehicles as far back as possible because they are going to supply everything down the chain of command from the HQ they are attached to anyway.
The most efficient use of infantry supply units in a way that doesn't create a micromanagement problem would be to use them to supply to MAA and HAA units away from the frontlines who are likely to be targeted by fighters on Flak Suppression missions, which don't target non-AA unit elements, and nowhere else as no other units would not be fired upon while having a draw on supply.