AGEOD Forums

Can anyone explain the mechanic of naval units blocking river crossings?
Happened to me several times but I just don't have a clue what is needed to work, is there any ratio of naval units vs ground forces that I have to meet to prevent them from crossing?

Here's what I've dug up:

Four naval elements have a 90% chance to block cross river movement; you can't get higher than this value; a single friendly fighting ship/boat in the river region will negates this.

Blocking a river crossing is a 23% chance per element, up to a max of 90%. The ships can't be in passive posture or have evade special orders. When trying to interdict mid turn, it seems that if the ships aren't in position before the enemy begins to march across, then your foe will make it across.

A naval combat element blocks a land stack using Riverine Transportation from moving through a water region. There is a possibility of combat occurring in such a water region, but it does not necessarily occur. Once the encounter occurs, if the land stack survives, it will drop to the shore in PP (Passive Posture), where it remains for the rest of the turn as a normal land stack, subject to all other rules pertaining to land stacks.

A couple more points.

- About naval combat elements encountering a land-stack using the RivTP (Riverine Transport Pool) to move through (not over) water regions(1), ie down the river. Only if the naval combat elements are in OP, will the movement be blocked and possible combat will ensue. Otherwise, the RivTP stack will simply sail away.

- Combat with a RivTP stack. I'm not sure what the status is currently, but I recall seeing a RivTP stack use it's Artillery to battle the naval combat elements.

- If a river region is patrolled by 4+ naval combat elements, if an enemy stack attempts to plot a move across that river region, the game will block plotting that move, although the moving stack would have a 10% chance of getting across, or the patrol could be plotted to leave the region. I'm not sure what would happen if you cannot see the patrol when you plot the move. Pocus said he'd fix this some time... when he get's around to it .....

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(1) When you cross a river, your stack does not actually touch the river region. They use a jump-link to cross it, which allows a stack to move from one region to a second region when the two regions do not actually physically touch each other.

I've had gunboats on orange/orange and they didn't block the other side from moving past using transport. I'm not referring to moving from one land region across the river to another but instead pure naval transport on the river.
Combat did take place but the surviving units still proceeded to move past.

For example as the union I place a stack of 6 gunboats just outside of Cairo IL on orange/orange. The AI playing as CSA moves a stack northward towards St. Louis. I see combat take place and I damaged the brigade being transported but it still got past the Cairo blockade. Wondering why the blockade didn't stop it?

BTW playing as CSA the same thing happens when I put 4-6 gunboats outside of Memphis. I still see the union getting troops past this.

Here's my hunch. The Wiki states that artillery on shore do a max of 50 hits to passing ships.

http://www.ageod.net/agewiki/index.php? ... ction=edit

":bmbMaxHitsDoneByLand = 50 // How many hit points can be done by Land units against a fleet "

What if a group of armed ships do the same?

Several times I have had a stack of 5 Blockade Squadrons catch a stack of 5 Runner units. That's 40 ships vs. 10, but instead of a slaughter, typically 8 Runners get away. It seems to me that ships only do X amount of damage per engagement. A squadron tasked with holding a section of river, might fire at the enemy until they are out of range and then continue to perform their assigned task.

If true that a stack can only inflict 50 max hit points of damage then it would make more sense to create two or three smaller groups than to combine into one large stack. Of course this can put you at a disadvantage in a pure ship to ship fight.

Or have several small stacks of shore artillery covering the river. I always split up the two batteries guarding the coastal forts.

Goodmongo wrote:I've had gunboats on orange/orange and they didn't block the other side from moving past using transport. I'm not referring to moving from one land region across the river to another but instead pure naval transport on the river.
Combat did take place but the surviving units still proceeded to move past.

For example as the union I place a stack of 6 gunboats just outside of Cairo IL on orange/orange. The AI playing as CSA moves a stack northward towards St. Louis. I see combat take place and I damaged the brigade being transported but it still got past the Cairo blockade. Wondering why the blockade didn't stop it?

BTW playing as CSA the same thing happens when I put 4-6 gunboats outside of Memphis. I still see the union getting troops past this.

You lost the naval battle. The winning fleet continued on it way.

Gray Fox wrote:Here's my hunch. The Wiki states that artillery on shore do a max of 50 hits to passing ships.

http://www.ageod.net/agewiki/index.php? ... ction=edit

":bmbMaxHitsDoneByLand = 50 // How many hit points can be done by Land units against a fleet "

What if a group of armed ships do the same?

That's the Bombardment Rule. It only counts for shore batteries bombarding passing ships.

Gray Fox wrote:Several times I have had a stack of 5 Blockade Squadrons catch a stack of 5 Runner units. That's 40 ships vs. 10, but instead of a slaughter, typically 8 Runners get away. It seems to me that ships only do X amount of damage per engagement. A squadron tasked with holding a section of river, might fire at the enemy until they are out of range and then continue to perform their assigned task.

Blockade ship are not terribly good in naval engagements. Brigs are great at evading combat. It appears, they escaped the engagement and went on their marry way.

Goodmongo wrote:If true that a stack can only inflict 50 max hit points of damage then it would make more sense to create two or three smaller groups than to combine into one large stack. Of course this can put you at a disadvantage in a pure ship to ship fight.

At the furthest forward river region you are guarding put your best fleet in OP (Offensive Posture); it's good to have Ironclad or Wood-clads here. But beware, in OP, they lose cohesion quickly, and will only be useful on station for maybe 3 turns at the most. You really need 2 good fleets, and having shore batteries to assist in fending off attacking fleets trying to get past is always a huge plus.

Gray Fox wrote:Or have several small stacks of shore artillery covering the river. I always split up the two batteries guarding the coastal forts.

I'm still not sure if that works, if the batteries are all in the same region. I believe, if they are in different region, they each fight their own bombardment.

Captain_Orso wrote:
You lost the naval battle. The winning fleet continued on it way.

How can you lose a naval battle when one side had 5 gunboats and the other side has just transports carrying a brigade?

I think I did lose this as my fleet was in defensive posture at the next turn. But if lost it was that my fleet got exhausted from shooting ducks on a pond so to speak and the transports survived.

But it does prove what I wrote. That even against only transports a combat fleet on orange/orange does not guarantee the other side from passing.

Captain Orso, I labeled my post a hunch.

http://www.ageod.net/agewiki/index.php? ... ction=edit

It also pertains to artillery on ships bombarding land targets, which would seem to me to be the same as artillery on ships bombarding, well, other ships.

The Blockade Squadron also contains a Steam Frigate and a Sail Frigate, so that was 5 of each vs. 10 brigs. Those should be terribly good at naval engagements. Yet, a limit on the damage done seemed probable.

Could you then please tell all of us how naval combat really works?

Goodmongo wrote:

Captain_Orso wrote:
You lost the naval battle. The winning fleet continued on it way.

How can you lose a naval battle when one side had 5 gunboats and the other side has just transports carrying a brigade?

I think I did lose this as my fleet was in defensive posture at the next turn. But if lost it was that my fleet got exhausted from shooting ducks on a pond so to speak and the transports survived.

But it does prove what I wrote. That even against only transports a combat fleet on orange/orange does not guarantee the other side from passing.

Fist off, in game-terms, you are not blockading. You can blockade an enemy harbor.

You're making me guess at your results from what little information you've provided. You did not provide a Save, nor state what the battle outcome of the combat was, only that the other side continued its move.

How? You left your fleet on station so long that it lost so much cohesion that it would have lost against 3 drunken Alabamans in a rowboat throwing their empties a weapons.

Gray Fox wrote:Captain Orso, I labeled my post a hunch.

http://www.ageod.net/agewiki/index.php? ... ction=edit

It also pertains to artillery on ships bombarding land targets, which would seem to me to be the same as artillery on ships bombarding, well, other ships.

The Blockade Squadron also contains a Steam Frigate and a Sail Frigate, so that was 5 of each vs. 10 brigs. Those should be terribly good at naval engagements. Yet, a limit on the damage done seemed probable.

Could you then please tell all of us how naval combat really works?

Bombardment is only between Ship and Shore - ONLY.

Blockade Flotillas have 6 Blockade Ships, crappy old tubs just good enough to sit in the way of other ships. Steam Frigates are pretty good at duking it out, but they are not fast and can easily be evaded. Sail frigates are the great at patrolling. They're fast, but Brigs are smaller, faster and often evade.

Naval Combat is pretty much the same as land combat, only there's no melee. There is frontage however, so a huge fleet does not in anyway mean you get to engage at will all of your ships at the same time. Also, the small, fast runners can often evade combat, or failing that, break off from combat and escape.

One consolation you have though, if you score any hits, they will be very expensive for the South to repair.

Captain_Orso wrote:
Fist off, in game-terms, you are not blockading. You can blockade an enemy harbor.

You're making me guess at your results from what little information you've provided. You did not provide a Save, nor state what the battle outcome of the combat was, only that the other side continued its move.

How? You left your fleet on station so long that it lost so much cohesion that it would have lost against 3 drunken Alabamans in a rowboat throwing their empties a weapons.

I had 5 gunboats fresh out of port the previous turn with each gunboat having 14-17 combat power under an admiral. The CSA had a brigade of ground troops it was moving past Cairo IL on its way towards St. Louis. They engaged each other. I inflicted 34 hits on the enemy and suffered zero hits. The enemy transports survived and continued on their way.

But I know why. On page 46 of the manual it says:
Finding the Enemy at Sea
You cannot directly stop an enemy’s movement through a sea region (or river), but
Evasion and Patrol Values will determine the probability of a naval engagement
occurring.

So this is opposite of what you wrote: "A naval combat element blocks a land stack using Riverine Transportation from moving through a water region. "

Naval combat elements do not prevent or block land units from moving on the river but can sink or damage them. And that has been my experience. Doesn't matter if you win or lose the engagement based on what the manual says.

I've never seen anything like this. If one side loses a naval battle, it is changed to PP. put in a neighboring region, nearly always the one from which it came, often into harbor if there is one accessible, where it remains the rest of the turn.

I would have to see the save to be able to repeat the turn and any more than that.

So this is opposite of what you wrote: "A naval combat element blocks a land stack using Riverine Transportation from moving through a water region. "

I did not write that. AFAIK, at stack using the RivTP (Riverine Transport Pool) aka "Riverine Transportation", will drop from the river into a neighboring land region upon contact with enemy combat elements. Actual River Transport Units are a different question. With those the transported land units will fight. This is a limitation of the game, since stacks using the RivTP are otherwise considered to be on River Transports.

Thanks good Captain to the info on naval warfare.