Why can the AI cheat out of naval battles?

[WhiteSlift]

As the UK, trying to get rid of the two old BBs Italy has, I've been raiding the seas for them for a couple of months. Every time I engage them, they close up to my ships and, in the middle of a battle, they disappear into another province. How is this possible, can the AI just de-spawn the ships? The player cannot retreat ships in the middle of a battle, they have to disengage first (which means they will still be in the battle display and can still be attacked and sunk). The AI however, can retreat its ships while they are still within firing distance of my ships. As seen in this screenshot...

...the Italians BB's are within immediate firing distance of the enemy ships, so as a player ,you could not retreat them unless they disengage all the way out of the battle screen. Yet after this screenshot, the ships were retreated only a couple of hours later. How can the AI do this, but the player cannot?

 

[Gingerninja]

I've seen this as well. Super annoying. You simply can't finish off those last 2 ships in a closed off space (for example the baltics) It shouldn't take years to take out that last cruiser in there.

 

[Alex_brunius]

When ships retreat depends on their remaining strength, so ships on low strength will retreat by disengaging from combat.

The following defines value in the game control when your fleets (called "navy") and individual ships will try to retreat from combat depending on how low strength they have and what repair setting they have:

REPAIR_AND_RETURN_PRIO_LOW_COMBAT = 0.1, -- % of total Strength. When below, navy will go to home base to repair (in combat).
REPAIR_AND_RETURN_PRIO_MEDIUM_COMBAT = 0.3, -- % of total Strength. When below, navy will go to home base to repair (in combat).
REPAIR_AND_RETURN_PRIO_HIGH_COMBAT = 0.5, -- % of total Strength. When below, navy will go to home base to repair (in combat).
REPAIR_AND_RETURN_AMOUNT_SHIPS_LOW = 0.2, -- % of total damaged ships, that will be sent for repair-and-return in one call.
REPAIR_AND_RETURN_AMOUNT_SHIPS_MEDIUM = 0.4, -- % of total damaged ships, that will be sent for repair-and-return in one call.
REPAIR_AND_RETURN_AMOUNT_SHIPS_HIGH = 0.8, -- % of total damaged ships, that will be sent for repair-and-return in one call.


If the AI ships instantly can get out of combat that might actually be a bug however. As you say they are supposed to have to disengage first and reach the end of their side before escaping from combat. I haven't actually seen this myself, do you perhaps have a savegame where it happens?

 

[SootyTX]

I've seen this happening all the time against Denmark and Norway. One particularly annoying Danish capital ship (don't recall if it was a BC or BB, but it was a 1936 design) was just hanging around off Copenhagen (wouldn't move or start a mission) and would be in a continuous series of battles with the Kriegsmarine;

1) battle starts, my fleet closes with the single enemy, the 200ish land based naval bombers and CAS I have in the area are all on a tea break (Luftwaffe clearly hanging out with the RAF prior to the war)

2) Danish ship closes in, rest of my fleet closes in, Danish ship shoots at a destroyer and damages/kills it

3) Combat aborts immediately, no chance to close on Danish ship and damage it with my (faster) capital ships

4) Combat immediately restarts and process repeats until I just cancel the patrol mission

5) Danish ship remains at sea off Copenhagen, Luftwaffe still having tea and refusing to attack (for the next YEAR)

6) I get totally fed up, tag over to Denmark and just disband the bloody thing.

 

[Foxador]

I've seen it happen the other way around as well where if the AI is winning a fight that your fleet will never leave combat. I've had troops trying to land on the UK and once they got next to the shore a few troops were engaged by subs. Now I know that the convoy's were pretty much going to die but what I did not expect was that the battle went on for a WHOLE MONTH. These convoy ships could've easily breached ashore but instead just stayed next to the shore line for a whole month just to let the subs slowly kill them.

 

[WhiteSlift]

When ships retreat depends on their remaining strength, so ships on low strength will retreat by disengaging from combat.

The following defines value in the game control when your fleets (called "navy") and individual ships will try to retreat from combat depending on how low strength they have and what repair setting they have:

REPAIR_AND_RETURN_PRIO_LOW_COMBAT = 0.1, -- % of total Strength. When below, navy will go to home base to repair (in combat).
REPAIR_AND_RETURN_PRIO_MEDIUM_COMBAT = 0.3, -- % of total Strength. When below, navy will go to home base to repair (in combat).
REPAIR_AND_RETURN_PRIO_HIGH_COMBAT = 0.5, -- % of total Strength. When below, navy will go to home base to repair (in combat).
REPAIR_AND_RETURN_AMOUNT_SHIPS_LOW = 0.2, -- % of total damaged ships, that will be sent for repair-and-return in one call.
REPAIR_AND_RETURN_AMOUNT_SHIPS_MEDIUM = 0.4, -- % of total damaged ships, that will be sent for repair-and-return in one call.
REPAIR_AND_RETURN_AMOUNT_SHIPS_HIGH = 0.8, -- % of total damaged ships, that will be sent for repair-and-return in one call.


If the AI ships instantly can get out of combat that might actually be a bug however. As you say they are supposed to have to disengage first and reach the end of their side before escaping from combat. I haven't actually seen this myself, do you perhaps have a savegame where it happens?

Hi, as a matter of fact I have found a savegame where this happens. One difference I noticed now is that the Italian ships do in fact start to disengage, but they disappear after a very short time. As far as I understand, they should only be able to retreat once they reach the border of the battle screen display (the map with the compass) by disengaging. The italian ships however, retreat for about 4-5 hours until they are gone, when they are still in the centre of the display. Look at the battle in the Western Mediterranean sea. Another thing that's really annoying is that they appear to be able to travel faster than the player-controlled ships - when I chase after them immediately after they're gone, they're already 2-3 provinces further away.

Here's the savegame: https://we.tl/mkSrkQFPIJ

 

[Axe99]

From what I can tell (noting I haven't looked closely and tested any defines since 1.1) is that there is a limit to how long a 'chase' against disengaging ships will go for, and it depends on the relative speeds between the chasing and chased fleet. There are defines that play with this, and when I've played with them I've managed to get endless chases (subs with no attack chasing convoys forever - it was for a test trying to get the timing of convoy battles more to my liking, you shouldn't get endless chases if you leave attack values for your ships ), but I didn't get a setting I was happy with at the time (although didn't pursue it closely either, as it wasn't what I was chasing - it was more a diversion).

I do think chases could stand to be longer, but it's worth keeping in mind that on many occasions in history slower ships have been able to break off combat with faster forces, through bad weather, the use of smoke and the threat of torpedo attacks, and the threat of subs or mines, amongst other things - so faster ships shouldn't _always_ be able to sink slower ships come-what-may - but I definitely think the way it works in-game at the moment could be improved.

Edit: Also, it's not an AI-specific behaviour, the same rules apply to your fleet as well, so no-one's "cheating" per se.

 

[Wyrm]

I wonder if relative speeds should have more of an impact. Far too many times I've had old slow capital ships escape from a fleet of brand new destroyers.

 

[Luckschaden]

Are you sure that they teleport away?

I think since the patch, ships run away more. So those battleships might hit your ships once and then THEY run away.

 

[Gingerninja]

There is no escaping. Usually they'd have to move out to the edge of the screen, but that doesn't happen. The battle just abruptly ends despite the ships beeing near the middle.

 

[Praetori]

There is no escaping. Usually they'd have to move out to the edge of the screen, but that doesn't happen. The battle just abruptly ends despite the ships beeing near the middle.

And it's not overly long battles or a sudden storm?

 

[Gingerninja]

Nope. Usually short battles. It usually happens right after the full might of my fleet has arrived. I assume that's when the Ai decides it's best to escape, and rather than spending a few hours escaping, the battle just ends. And then restarts a second later. And all of that on repeat foe months.

 

[WhiteSlift]

There is no escaping. Usually they'd have to move out to the edge of the screen, but that doesn't happen. The battle just abruptly ends despite the ships beeing near the middle.

This is what happens in my savegame. Italian BB is in the middle, retreats for 4-5 hours (is still in the middle though), and the battle ends.

 

[Praetori]

This is what happens in my savegame. Italian BB is in the middle, retreats for 4-5 hours (is still in the middle though), and the battle ends.

That, I believe is WAD. If it's retreating for a couple of hours but can't fully outrun it's opposition but still eligible for damage in one form or anther (even though none of your ships are in firing-range) then it will stay close to the middle when it's in fact leaving the sea-zone. A bit counter-intuitive yes.

 

[Gingerninja]

So it's wad that a slow BB can be on the run from a massive fleet in one naval area for months? Outrunning LC, DD, HC, BC.

 

[SootyTX]

That, I believe is WAD. If it's retreating for a couple of hours but can't fully outrun it's opposition but still eligible for damage in one form or anther (even though none of your ships are in firing-range) then it will stay close to the middle when it's in fact leaving the sea-zone. A bit counter-intuitive yes.

That's not what's happening (and even if it was, if that's WAD then its absolutely terrible design). I had HMS Rodney, alone, in the South China Sea, being engaged by fleets of mixed carriers, capital ships and screens, all 3 fleets at least 35 ships. And every time, my destroyers close fast, one or two get destroyed, Rodney is still moving towards the centre along with the rest of my ships, then goes 'peace out biatches' and the battle ends, to restart literally 3 seconds later with virtually the same result. Getting Rodney from 75% strength to 30-odd % strength took about 40 battles and cost me over 30 destroyers, meanwhile my hundreds of aircraft and 10s of 1940 generation BBs, BCs and CAs spent almost the whole time drifting around on the side of the screen.

And as others note it goes both ways, so its not a hidden AI cheat being exposed., I've also had the month long subs vs invasion convoy at the beach thing as well. Whatever they did with naval combat with 1.2 is seriously screwed up.

It doesn't help that the naval combat screen itself it virtually useless insofar as being able to tell what the hell is going on in the maneuver battle.

 

[Praetori]

So it's wad that a slow BB can be on the run from a massive fleet in one naval area for months? Outrunning LC, DD, HC, BC.

If it retreats to a sea zone where the opposition in question is not patrolling or if it retreats beyond detection then yes. Then if you put it in the context of running for months it of course get weird. I'm not saying the behavior is good but on the other hand catching ships with some manner of range, weather or speed advantage was no easy task (there were many medium to large surface raiders and even carriers ghosting around the oceans during the war) . It should however be better conveyed in the GUI what's going on and the popup naval battles that never end or end with hardly a shot being fired are a nuisance at best, I'd rather have the ghost-ship slip under the detection threshold.
They key should be detection and counter detection. A fleet that has spotted and identified the enemy has a huge advantage compared to the fleet/ship that doesn't know she's steaming into danger.

 

[SootyTX]

If it retreats to a sea zone where the opposition in question is not patrolling or if it retreats beyond detection then yes. Then if you put it in the context of running for months it of course get weird. I'm not saying the behavior is good but on the other hand catching ships with some manner of range, weather or speed advantage was no easy task (there were many medium to large surface raiders and even carriers ghosting around the oceans during the war) . It should however be better conveyed in the GUI what's going on and the popup naval battles that never end or end with hardly a shot being fired are a nuisance at best, I'd rather have the ghost-ship slip under the detection threshold.
They key should be detection and counter detection. A fleet that has spotted and identified the enemy has a huge advantage compared to the fleet/ship that doesn't know she's steaming into danger.

Early war maybe, although once engaged by a superior force in terms of speed and significant numbers, which is what most of us are seeing, even then no. Late war, with carrier fleets, radar on many capital ships, land based spotter planes, then absolutely not.

What we are talking about here is well past the detection stage. This isn't "Hunt the Bismark", this is "found the Bismark, got it pinned by 3 fleets of multiple carriers and capital ships, start firing on the Bismark and it a does a Philadelphia Experiment on us". Or maybe a Picard Maneuver, since it seems to teleport a few miles away and we start the whole thing all over again.

Add on all the other wierdness that's cropped up - fleets just sitting around with no mission being immune to naval bombers and CAS, month-long landing operations with subs sinking one transport a week and everything that's been reported in this thread and you've got a patch that has introduced some serious issues into the naval game (which was hardly stellar to start with).

 

[Meglok]

Early war maybe, although once engaged by a superior force in terms of speed and significant numbers, which is what most of us are seeing, even then no. Late war, with carrier fleets, radar on many capital ships, land based spotter planes, then absolutely not.

What we are talking about here is well past the detection stage. This isn't "Hunt the Bismark", this is "found the Bismark, got it pinned by 3 fleets of multiple carriers and capital ships, start firing on the Bismark and it a does a Philadelphia Experiment on us". Or maybe a Picard Maneuver, since it seems to teleport a few miles away and we start the whole thing all over again.

Add on all the other wierdness that's cropped up - fleets just sitting around with no mission being immune to naval bombers and CAS, month-long landing operations with subs sinking one transport a week and everything that's been reported in this thread and you've got a patch that has introduced some serious issues into the naval game (which was hardly stellar to start with).

Just curious, did you try engaging it with only faster ships like BCs and CA's plus screen? Or try throwing NAV air into the mix?

Not saying there isn't another bug in the new naval system after the issues Sterrius found, just trying to understand under what circumstances this does or doesn't happen.

 

[SootyTX]

Just curious, did you try engaging it with only faster ships like BCs and CA's plus screen? Or try throwing NAV air into the mix?

Not saying there isn't another bug in the new naval system after the issues Sterrius found, just trying to understand under what circumstances this does or doesn't happen.

I'm moderately sure (as in, 98.5%) that all my ships were faster. I'd dumped all the tier ships into patrol groups around the islands, so these were pure tier 2 or better with engine upgrades (to keep up with the carriers). Given that Rodney was not exactly the quickest hunk of junk on the sea, I probably had several knots on her even with my slowest BBs. And air was included, both carrier and shore based.

It seems to be triggered by large numbers differences - I've seen it very consistently when trying to beat down the last one or three ships from a fleet, large scale actions don't have the same issue that I've seen. And I'm not doomstacking, I play very historically (which is a total 'mare with the IJN as I really don't know what the different fleet names are and keep having to inspect them, lol) so my fleets are based real compositions rather than idealized numbers like Sterrius recommends (not to nay-say his work at all, its very interesting to read).