How to blow bridges?

[bram1979]

Like the title says...

How do you blow a bridge?

I've tested with satchel charges and artillery but now effect. Is there a way to blow a bridge?

[kohlenklau]

Anecdote: I was doing a playtest of a new scenario I am working on and it has a wooden vehicle bridge. I have an initial Soviet AI 120mm mortar sporadic fire during the first few turns and a direct hit destroyed the bridge. Haven't seen it happen again.

[nik mond]

Depending on the ordinance it is possible to destroy some bridges with heavy artillery, maybe heavy mortars as well. I have destroyed stone bridges and canal bridges with heavy long artillery barrages. Takes a bit of luck, or bad luck if you do it without intending to

[umlaut]

This one of those questions that pops up at regular intervals. As far as I am aware, the official answer is something like this:

You can´t blow bridges with satchel charges, only with artillery - but you´ll need a lot of of it.

You can´t use charges, because the time it takes to rig a bridge for demolition is outside the timespan of an ordinary CM game.

Personally, I think that explanation sounds pretty fair - I would hope, though, that BFC would give scenario designers the option to make a bridge already rigged for demolition when a scenario starts. But knowing BFC, my guess is that this would be very far down their list of priorities.

Cheers

[Oddball_E8]

With artillery...

Lot's and lots of artillery...

[MikeyD]

I recall playtesting an initial version of someone's scenario. You were on one side of a river, the objective on the other, but the AI's opening barrage kept knocking down the two bridges that were your only route out of the setup zone! Needless to say, that opening barrage got adjusted somewhat.

[sburke]

It used to be that a direct fire 81 mm mortar could take down most bridges given enough ammo in a few turns. That no longer appears to be the case for most bridges. Good to know

[cool breeze]

MikeyD, was that the second to last mission of the italian campaign where the two battleship prep barrages land right on the other side of the birdges? Just out of curiosity. Reminds me I need to finish that fun campaign.

[womble]

Or arrange for a (preferably enemy) vehicle with lots of HE on board to start burning on the bridge. The eventual catastrophic cookoff will go a long way towards dropping the span.

[JoMac]

-Or- just use some Infantry Grenades to take down a Bridge...Just 1-2 of them Sure does a job immobolizing Tracks on Armor near %100 of time...Sigh.

Joe

[YankeeDog]

...I would hope, though, that BFC would give scenario designers the option to make a bridge already rigged for demolition when a scenario starts...

The reason this isn't a very good idea is that the existence or nonexistence of a major bridge pretty radically changes the tactical situation for a scenario. If the demolition succeeds, the attacker may have no practical way of winning. Or if it fails, the attacker may have a cakewalk.

For these reasons, it's generally much better to design such that the battle starts either immediately after the bridge demolition has happened, or covers the battle leading up to the demolition (or failure thereof) -- for example:

"The retreating Germans just dropped the main span across the river in this area, but there are two small fords nearby. Cross your force at the fords, and size the high ground on the far side so that engineers may repair the bridge without interference from enemy fire."

Or....

"Engineers have not yet finished priming the bridge for demolition. Your task is to delay the enemy advance for X time until the bridge can be demolished."

Or...

"There is an intact bridge across the river ahead, but the enemy is sure to blow it given time and opportunity. Advance aggressively and seize the bridge before it is destroyed!"

So while the premise of a scenario can center around control and destruction (or prevention of destruction) of a bridge, it's generally better for the actual demolition to take place outside of the scope of the CM scenario.

I respect that players would like to have the eye candy of the bridge demolition, but in storywriting terms, events event are much better used as the instigation or the resolution of the plot, rather than mid-story.

[umlaut]

The reason this isn't a very good idea is that the existence or nonexistence of a major bridge pretty radically changes the tactical situation for a scenario. If the demolition succeeds, the attacker may have no practical way of winning. Or if it fails, the attacker may have a cakewalk.

Well, I think these are some pretty large "ifs". It is of course up the scenario designer to design the scenario in a way that would eliminate such "ifs". For instance by making sure that there are other avenues available for the attacker, etc.

I don´t think game features should be excluded from the game simply because they could hypothetically be used to make scenarios unwinnable. If we were to follow that logic there shouldn´t be any rivers in the game - because "what if" the attacker can´t reach the objectives because the scenario designer hasn´t placed any bridges or fords on the river?

Poor scenario design can never be eliminated by blocking access to certain game features.

[MikeyD]

Lets not forget there are bridges and there are bridges. The littlest foot bridge will fall over in a strong gust of wind. I've seen grenades take them down. The monster bridges in the Arnhem module they didn't bother making destroyed model versions because these beasts were functionally indestructible... excepting engineers taking three days to rig demolition charges to bring down a span - something outside the game's scope

[YankeeDog]

Well, I think these are some pretty large "ifs". It is of course up the scenario designer to design the scenario in a way that would eliminate such "ifs". For instance by making sure that there are other avenues available for the attacker, etc.

I don´t think game features should be excluded from the game simply because they could hypothetically be used to make scenarios unwinnable. If we were to follow that logic there shouldn´t be any rivers in the game - because "what if" the attacker can´t reach the objectives because the scenario designer hasn´t place any bridges or fords on the river?

Poor scenario design can never be eliminated by blocking access to certain game features.

Except that you're talking about a game feature that would take a large amount of time to code and debug. Getting bridge priming and demolition would be very complicated, even if you only allowed "pre-primed" bridges (i.e., bridges that were primed to blow at the start for the battle).

What should the % success be? Even carefully prepared demolitions sometimes fail. If a demolition does fail, should there be a chance to reset, and if so, how long should this take? What if the triggerman is under fire? Does this decrease the chance of a successful demolition, and, if so, by how much? Can the wires/fuses potentially be cut by artillery fire or similar? If enemy forces reach the bridge before it's blown, can they the defuse the charges? If so, just specialist engineers, or any troops? And how long should defusing take? Should there be a chance of accidentally setting off the charges while attempting to defuse?

Huge amounts of work for IMHO an feature that would only be applicable to a very limited set of potential scenarios, that I don't think would be very fun to play anyway.

Far better for BFC to spend its "game improvement" capital elsewhere.

As a side note, I would love to see some new game features added to how the game models the combat engineering and obstacle breaching battle, but demolishable bridges is not very high on my list. E.g., more options for minefield and obstacle breaching, "hasty minefields" that would be easily visible but would still need to be removed to cross safely, assault boats and possibly amphibious vehicles for crossing water obstacles, etc.

[Broadsword56]

One way you can simulate a battle where a bridge could blow during play if not first seized intact is with a touch objective.

Draw it in a thin touch objective line, in arcs measuring, say, 500m from either side of the bridge. Set the touch objective to "known to" only the defending player.

Now you've simulated a primed bridge, where the defenders have orders not to blow it until it's in imminent danger of capture. When any attacking units touch the danger line, the game will give the defending player a message alert. Then then the game can be paused while some other mechanism (say, a die roll) is used to determine if the bridge is blown.

If the bridge blows, the battle ends there. If the demolition attempt fails and bridge doesn't blow, the the wires have been cut and it's "disarmed." Battle continues and the attacker still has the chance to fight for and capture it.

I've adapted the Where Eagles Dare boardgame rule, for example, to have demolition succeed on a D10 roll of 6 or less if any unsuppressed defending unit has LOS and LOF (working weapon, has ammo) to any AS within either of the danger zone areas, or 5 or less if the defending side fails to meet this condition.

My Son map for CMBN-MG (which I posted in the Repository) was designed to be played this way.

What's cool about the "known only" to defender setting for the touch line is that the attacking player must tread carefully the closer he gets to the demolition radius. He can use the LOS tool to estimate how close he is, of course, but he doesn't know exactly where that thin line is. So he can't brazenly walk right up to it, and could even trip it prematurely or unintentionally.

[sburke]

I think I am with YD on this. Not much bang for the buck. I am thinking of Remagen and Nijmegen as scenarios. Basically the battle comes down to the moment the defending side goes to blow the bridge. There is no command dysfunction to interfere like Nijemegen even. The defender just says using whatever mechanism - blow bridge and the scenario is over. If the bridge blows defender wins, if not they lose.

The list of things we'd all like in CM is quite long, better to focus on things that make a difference more often. Having said that, if the capability is added next week I wouldn't be upset.

[Michael Emrys]

The defender just says using whatever mechanism - blow bridge and the scenario is over. If the bridge blows defender wins, if not they lose.

I don't think it has to be that black and white. Consider this scenario: The defender wants to keep the bridge open as long as possible. He may have units that he needs to evacuate over it. Or he may feel that if he can hold it, it will allow a later counter-attack. So you have a sliding scale of points with more points being won the longer he can avoid blowing it with a big bonus if it is still open at the end. The attacker wins points for capturing it intact (obviously). That will be difficult to do although the sooner he can take it, the less likely the demolition will work. If the demolition works anyway, he can still win points by forcing the defender to blow the bridge sooner than he would like. So the name of the game for the attacker is to move fast, and for the defender to delay, delay, delay. Which is, I think, an acceptable representation of a real life event, and would also make for an interesting gaming situation.

But all that said, I don't know how much development effort would be required to make this work. Since it is not the kind of thing that is going to turn up in many scenarios, that then raises the question of whether it would be worth that effort.

Michael