Bridges

Beginning with revision 2.654 several new bridge models were introduced. Accompanying this introduction were new load bearing limits for all bridges. Try to move a vehicle that is too heavy over too light of a bridge and you'll end up with a recovery operation rather than a crossing. Additionally, bridge sections may be destroyed by certain types of attacks during the action phase.

Set out below is a guide to what the bridges look like, what weight they will bear, what types of ordinance will bring them down, their Map Editor ID number, along with game play and map making tips.

Bridge Classification

The classification system is as follows:

CLASS 0: weak ~10t

CLASS 1: light ~30t

CLASS 2: medium ~50t

CLASS 3: heavy ~100t

CLASS 4: super heavy ~200t

CLASS 5: nearly invincible ~400t

Bridge Description	Bridge Classification	Object Number in Map Editor	Image of Bridge
Wooden – 1 lane Damaged by: Arty (HE), Main Gun direct-fire (HE/HEAT), IED, and Air Strike; Damage spannable by AVLB: No	CLASS 0	449
Concrete – 1 lane Damaged by: IED and Air Strike only; Damage spannable by AVLB: Yes (single span - Bieber only)	CLASS 2	446
Concrete – 2 lane Damaged by: IED and Air Strike only; Damage spannable by AVLB: Yes (single span - Bieber only)	CLASS 3	447
Stone – 2 lane Damaged by: IED and Air Strike only; Damage spannable by AVLB: Yes (single span - Bieber only)	CLASS 3	66
Stone – Rail Damaged by: IED and Air Strike only; Damage spannable by AVLB: Yes (single span - Bieber only)	CLASS 3	442
Concrete – 4 lane Damaged by: IED and Air Strike only; Damage spannable by AVLB: Yes (single span - Bieber only)	CLASS 4	448
Concrete Highway Damaged by: IED and Air Strike only; Damage spannable by AVLB: Yes (single span - Bieber only)	CLASS 5	444
Green 2 Lane Truss Damaged by: IED and Air Strike only; Damage spannable by AVLB: No	CLASS 5	445
Red Rail Truss Damaged by: IED and Air Strike only; Damage spannable by AVLB: No	CLASS 5	443

Gameplay Considerations

Crossing Bridges

Although much improved over various revisions, in Steel Beasts Professional even administrative bridge crossings can occasionally prove a challenge. When conducting such crossings in the presence of enemy elements, well, “disaster” is not too strong of a term to describe the outcome. In order to minimize such situations, scenario designers and players alike should keep the following tips in mind :

1. Ensure the Military Load Classification (MLC) of your vehicles doesn't exceed that of the intended crossing point. Players should conduct recce to confirm that bridge can take the weight; an MLC 60 tank trying to cross MLC 10 wooden bridge not a good look.

2. Plot a "normal" Troop/Platoon route (i.e. to conform to whatever their task is) up to a point approximately 150m short of bridge.

3. Assuming no enemy contact is expected, plot a new march route across bridge (using shift click to lock onto the road and putting in a way point either side of the bridge) with a slow speed; you can also select wide spacing for further confidence.

4. 150m plus of bridge create new route (or add to an existing one) going back to what they were doing before the bridge.

Basically this gives them room prior to the bridge to go from say assault in line, flat out, to slow, wide spaced, in column. They then cross the bridge. Then they can spread back out and continue after the defile.

Crossing a laid bridge not much different (except maybe no road the lock the route to with the "shift click"): When enemy contact is not expected, all units should utilize a single column formation route using “March” tactics and the waypoints at either end should be located well away from the bridge to give units time to transition from and back to whatever formation they had.

If an enemy presence is suspected, players should attempt to find an alternate route or ford, an eventuality scenario designers may wish to plan for, but if the bridge crossing must be executed, it should instead be treated as a breaching operation. Apply the tenets of SOSRA:

• Suppress the enemy with direct and indirect fires.
• Obscure the crossing point with smoke.
• Secure the far-side with a small assault force.
• Reduce the obstacle, in this case destroying any enemy forces that can observe/place fire on the crossing point.
• Assault remaining friendly forces across the bridge in small packets.

When attempting such a contested crossing, the basic operation stays the same: placing way points at either end and located well away from the bridge to give units time to transition, but the points should placed further out (200m) and the route type changed to either assault or breach.

Bridge Destruction and Crossing Damaged Bridges

As noted in the bridge descriptions, all fixed bridges may be damaged during the action phase by various means. As this can have profound effects on the outcome of a scenario, designers must take care with the assets they choose to allow to players, and understand the limitations of those assets.

Damaging Bridges
For the purposes of this discussion we will ignore the light wooden bridge (map object 449) as it is easily damaged and cannot support the weight of an AVLB, this means the only ways to damage a bridge during the action phase is either an air strike, or the use of a preplanned IED.

Air strikes are highly inconsistent, especially against one and two-lane bridges, even when called from dedicated FO vehicles, and multiple strikes may be necessary; there is no guarantee of success. Regardless, air strikes do offer the possibility of a damaged bridge still being useable by appropriately equipped forces, but it is impossible to ensure only a single segment will be destroyed, so this method should not be relied on. In any scenario where one or more bridges are critical to either side's mobility, scenario designers may wish to eliminate or severely curtail player access to air strikes.

Preplanned IEDs are used with the intent of denying the use of a given bridge to all players, as the IED blast will always drop more than one bridge segment. Scenario designers wishing for a “damaged” bridge with a gap spannable by AVLBs should manually create the desired gap in the map editor.

Crossing Damaged Bridges
WIP

Considerations for Map Makers

Maximum Bridge Height
Each bridge type possesses an approximate maximum deck height listed below. Attempting to span dry gap deeper than a given bridge's height will result in the bridge supports floating above the underlying terrain. Note that all bridges, with the exception of the wooden and truss bridges, arch over gaps and with the listed heights measured from the tallest point of the bridge.

Stone bridges (66, 442): 26m
Truss bridges (443, 445): 34m
Heavy concrete highway bridges (444, 448): 34m
Light concrete 2 lane (447): 31m
Light concrete 1 lane (446): 28m
Wooden bridge (449): 16m

Overpasses
As of yet, there is no "overpass" type object modeled in Steel Beasts Professional, but a work around exists. Prior to version update 2.654, road traffic passing under elevated spans could not proceed due to the structure of the existing bridge object, but this is no longer the case, and current bridges may overpass roads while still allowing traffic movement. Understand there are caveats to this:

• All single and two-lane roads may pass between the supports of all bridges with no traffic impediment as long as sufficient overhead clearance is available and the road kept centered.
• Four-lane highway objects can safely straddle all bridge supports (i.e. the support lays parallel the road and within the median) with the exception of truss bridge supports, which the road will comfortably fit between.
• The standard four-lane paved road object only just fits between the supports of most bridges, with the supports resting on the shoulders parallel to the road. This places the supports very close to the outside lanes, and although it won't stop traffic from flowing, the A.I.'s object avoidance routine will cause vehicles to move toward the center of the road and this may lead to traffic jams. As with the divided highway object, this road will fit between the supports of both truss bridges with no interference.

In all cases, road placement is critical to allow for proper traffic flow.