Dry Support Bridge

The M18 DSB system brings a revolutionary change to the Multirole Bridge Companies (MRBC). The Dry Support Bridge (DSB) relies on a mechanical system to significantly reduce soldier effort and improve operational capability to the force. The DSB replaces the medium girder bridge (MGB), while doubling the gap-crossing capability of each MRBC. It is intended to fill all 40-meter-or-less, dry-gap bridging roles from the brigade rear to the communication zone ports in a variety of tactical situations.

Each MRBC is authorized four DSB systems, each consisting of an M1975 launch vehicle and a modular bridge that can span gaps up to 40 meters. A crew of eight soldiers can transport the entire system and deploy a 40-meter bridge in 90 minutes or less. Bridge loads are modular and palletized onto seven flatracks that are transported via organic Common Bridge Transporters (CBT) and Palletized Load System (PLS) trailers. Soldiers can also construct two shorter bridges, up to 22 and 28 meters long respectively, from each DSB system.

The M18 DSB system is composed of two subsystems, the M1975 launcher vehicle and the M19 DSB. The M1975 uses a hydraulically operated launch system integrated onto a standard PLS chassis and a set of launch beams that is carried as a separate palletized load. A launch beam is cantilevered over the gap that supports the bridge as it is built and projected across the gap. The labor required to emplace and remove the bridge is significantly reduced by the use of an integrated, materiel-handling crane, as well as by the ability of CBTs to maneuver the palletized bridge loads around the construction site easily.

The M19 DSB is a modular, all-aluminum bridge. Although some of the components seem similar in design to the MGB, the number of components has been drastically reduced and the bridge is a new design. A 40-meter bridge consists of 2 ramp modules, 5 parallel modules, 2 end beams, 20 approach ramps, and 24 bridge pins. Each module has curbs and drivers’ aids integrated into it, and modules fold up onto themselves for transportation. The bridge has a 4.3-meter roadway and supports Military Load Class (MLC) 80T (tracked)/110W (wheeled). The bridge is also fielded with a new anchorage system for longer-term use. To further reduce labor requirements, the anchorage system features an onboard pneumatic hammer, which is powered via standard connections to the launcher vehicle or organic CBTs.

The DSB program transitioned into full-rate production in May 2003 and attained full materiel release in June 2003. The Program Manager for Bridging fielded four DSB systems to the 74th Multirole Bridge Company in February 2003 just before its deployment to Southwest Asia, and the system successfully supported operations there.

--- This data is from the April-June 2004 issue of Engineer, by Lieutenant Colonel Andrew DiMarco. Content modified by Don Busack.

Dry Support Bridge Specifics

1 DSB System consists of:

1 Launch vehicle + launch beams on LVT
Bridge Load V1 - 2 parallel modules + T1 - Approach ramps/ramp module
Bridge Load V2 - 2 parallel modules + T2 - 1 Parallel Module
Bridge Load V3 - 2 ramp modules + T3 - Approach ramps
Crew of 8 soldiers

All trailer and M1977 loads are palletized loads, the launch vehicle (M1975) is mounted on a PLS chassis, but is not removable.

The unit consists of:

1 - M1975 Launch Vehicle
3 - M1977 Common Bridge Transporters
4 - M1076 PLS Trailers

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