OK, I think I found a solution to one of TOAWs scenario design challenges, which is how to simulate invasions, or more to the point, beachheads and their supply.
Most of the time designers will just put a friendly supply point on a beach hex, but that creates some problems, for example either the invasion army is unsupplied because the enemy managed to recapture exactly that hex, or an invasion army will be in supply despite his opponent having thrown up a formidable sea blockade which should have cut off any supply shippment. Also your invasion army is always at the maximum supply level, even if they had to land at ports which shouldn't allow full supply to be landed.
One solution was the invention of sea-supply-roads, but they had the negative side effect that units at the beach had a habbit of retreating onto this supply road instead of stubbornly defending the beaches. Another minus was that all beach hexes connected to this supply road network were automatically supplied, and no matter how strong the defenders airforce was, it was impossible to simuate destroying the merchant fleet by air to stop the supply from flowing.
I found a way which allows the player to choose exactly which beach he wants to supply, it even allows him to swicht his resupply efforts to a different beach during the game, it prevents landed units from beeing pushed back on supply roads and it even allows the destruction of the supply fleet and thereby to cut all supply to the beaches!
The solution is realtive simple, I created this sea-road network 2 hexes from the beaches, and put a super-river between the sea-road supply line and the beaches (these super rivers can't be seen, as they are masked by the deep sea hex), over which the sea-roads connected the supply point with the beaches. Than I destroyed all bridges over these super rivers and thereby cut all supply to the beaches.
If a player wants to get the supply flowing again, he has to move a special merchant-fleet/supply unit onto this destroyed-bridge hex (it is a ferry-bridging unit with some engineers and ferry-bridging squads), which will than work as a bridge (it should NOT repair the bridge, just stand there), allowing the supply to flow to the beach again. But if this merchant-fleet unit is destroyed, all supply will be stopped again.
And as this hex is treated as deep water, no unit can enter it from the land, not even a merchant-fleet unit should it for whatever reason beeing pushed off that hex. The only way to enter this hex is in embarked status.
This is the overview from a test scenario (scenario is attached to this post), it shows the supply road network and the blown-bridge hexes.
This is what happenes to a landing force without a supply unit to connect the beaches to the supply network, they are out of supply.
This is the same landing, but now with a supply unit present to connect the beaches to the supply network.
Please note that the supply starts to flow even while the supply unit is still embarked, landing forces will thereby be supplied from day 1 of their invasion. This is also a pretty good simulation for supply that has to be landed onto the beaches, the embarked unit is pretty vulnerable to enemy air attacks and wont survive long without total air supremacy. Additionally it consumes shippment points, lowering the amount of troops that can be transported, as these ships are now used for supplys instead.
It's also still mobile, so should the need arrise to supply a different part of the landing zone (maybe because your units got cut off somewhere by a counterattack) you could simply move this supply fleet to a different part of the network, which of course always holds the risk that you'll leave your protective area and have to move out of fighter cover, putting your entire merchant fleet at risk.
To simulate the mulberry ports I suggest that the player disembarks this supply unit at this hex, supply will still flow, units still can't be pushed onto that hex, the mulberry is now stationarry and has a greater resistance against enemy air attacks.
Designers can also simulate difficult beaches where it would be hard to land supplies or which are too far away from your own harbors, and lower the supply to this locations by using +distance hexes.
This is a landing with a +1 distance put onto the hex where the supply unit is parked:
As you can see, the first few hexes are still in 50 supply.
Now the same situation with a +20 distance hex at the same location:
I hope this'll help to better simulate some of the difficulties planers had when preparing a seaborn invasion
Most of the time designers will just put a friendly supply point on a beach hex, but that creates some problems, for example either the invasion army is unsupplied because the enemy managed to recapture exactly that hex, or an invasion army will be in supply despite his opponent having thrown up a formidable sea blockade which should have cut off any supply shippment. Also your invasion army is always at the maximum supply level, even if they had to land at ports which shouldn't allow full supply to be landed.
One solution was the invention of sea-supply-roads, but they had the negative side effect that units at the beach had a habbit of retreating onto this supply road instead of stubbornly defending the beaches. Another minus was that all beach hexes connected to this supply road network were automatically supplied, and no matter how strong the defenders airforce was, it was impossible to simuate destroying the merchant fleet by air to stop the supply from flowing.
I found a way which allows the player to choose exactly which beach he wants to supply, it even allows him to swicht his resupply efforts to a different beach during the game, it prevents landed units from beeing pushed back on supply roads and it even allows the destruction of the supply fleet and thereby to cut all supply to the beaches!
The solution is realtive simple, I created this sea-road network 2 hexes from the beaches, and put a super-river between the sea-road supply line and the beaches (these super rivers can't be seen, as they are masked by the deep sea hex), over which the sea-roads connected the supply point with the beaches. Than I destroyed all bridges over these super rivers and thereby cut all supply to the beaches.
If a player wants to get the supply flowing again, he has to move a special merchant-fleet/supply unit onto this destroyed-bridge hex (it is a ferry-bridging unit with some engineers and ferry-bridging squads), which will than work as a bridge (it should NOT repair the bridge, just stand there), allowing the supply to flow to the beach again. But if this merchant-fleet unit is destroyed, all supply will be stopped again.
And as this hex is treated as deep water, no unit can enter it from the land, not even a merchant-fleet unit should it for whatever reason beeing pushed off that hex. The only way to enter this hex is in embarked status.
This is the overview from a test scenario (scenario is attached to this post), it shows the supply road network and the blown-bridge hexes.
This is what happenes to a landing force without a supply unit to connect the beaches to the supply network, they are out of supply.
This is the same landing, but now with a supply unit present to connect the beaches to the supply network.
Please note that the supply starts to flow even while the supply unit is still embarked, landing forces will thereby be supplied from day 1 of their invasion. This is also a pretty good simulation for supply that has to be landed onto the beaches, the embarked unit is pretty vulnerable to enemy air attacks and wont survive long without total air supremacy. Additionally it consumes shippment points, lowering the amount of troops that can be transported, as these ships are now used for supplys instead.
It's also still mobile, so should the need arrise to supply a different part of the landing zone (maybe because your units got cut off somewhere by a counterattack) you could simply move this supply fleet to a different part of the network, which of course always holds the risk that you'll leave your protective area and have to move out of fighter cover, putting your entire merchant fleet at risk.
To simulate the mulberry ports I suggest that the player disembarks this supply unit at this hex, supply will still flow, units still can't be pushed onto that hex, the mulberry is now stationarry and has a greater resistance against enemy air attacks.
Designers can also simulate difficult beaches where it would be hard to land supplies or which are too far away from your own harbors, and lower the supply to this locations by using +distance hexes.
This is a landing with a +1 distance put onto the hex where the supply unit is parked:
As you can see, the first few hexes are still in 50 supply.
Now the same situation with a +20 distance hex at the same location:
I hope this'll help to better simulate some of the difficulties planers had when preparing a seaborn invasion