An improved ribbon bridge (IRB) is in production by EWK Eisenwerke Kaiserslautern GMBH. Testing for the IRB began in 4QFY01. Testing for the IRB began in 4QFY01. The IRB increases military load classification (MLC) ratings, increase ramp length, and allows for bank heights up to 2 meters. The Improved Ribbon Bridge provides bridging and ferry capabilities as part of the US Army's Multi-Role Bridging Company. The IRB is fully interoperable with the Standard Ribbon Bridge (SRB). The IRB bridge bays are a similar design as those of the SRB and retain the same operational requirements.
A rollout ceremony was held for the IRB at Anniston Army Depot on 04 June 2001. The IRB was developed by prime contractor Eisenweke Kaiserslautern in Kaiserslautern, Germany for the U.S. Army, and provides bridging and ferry capabilities as part of the U.S. Army Multi-Role Bridge Company. ANAD and AM General are the two subcontractors. This is a 5-year contract for 211 interior bays and 82 ramp bays with additional options of 107 and 43 respectively. ANAD will manufacture two each of the outer pontoons for each interior bay, as well as paint, assemble and test these items. Additionally, ANAD will paint the ramp bays manufactured by EWK.
The new Multi-Role Bridge Company is a marriage of organization and materiel allowing engineers to treat bridging assets as a commodity. This company, equipped with the Common Bridge Transporter (CBT) truck, provides the maneuver commander with the bridge needed, where it is needed, when it is needed whether that bridge is the Heavy Dry Support Bridge (HDSB) the Improved Ribbon Bridge (IRB) or the Line of Communication Bridge (LOC Bridge).
The Improved Ribbon Bridge is employed in the same general manner as the standard Ribbon Bridge. However, it will be able to cross faster water with higher MLCs and with banks that are up to two meters high. The Improved Ribbon Bridge bays are modified ribbon bays. The posses better hydrodynamics, providing the capability of rafting or bridging MLC 70T traffic in currents up to 8 fps. The bays can be connected in one minute and can be connected to the standard ribbon bays. The bays include postive flotation to increase the survivability of the system. The ramp bays can be hydraulically articulated to two meters.
The Improved Ribbon Bridge (IRB) is a modular floating bridge with integral superstructure and floating supports. A complete IRB consists of a ramp bay at each bank and the required number of interior bays to complete the bridge. Individual bays may be joined to form a raft for ferrying operations. Each bays is transported in a folded position on a Common Bridge Transporter and held in place by a Bridge Adapter Pallet. The bays unfold automatically in the water as a result of buoyant forces that actuate a cable and lever system. The IRB mission is to provide a continuous roadway or raft capable of crossing assault or tactical vehicles over nonfordable wet gaps. IRBs will have a Military Load Capacity of 96.
Reliability in action, fast and robust handling and interoperability with the US Ribbon Bridge made the FSB-1 a well-known and proven engineer equipment. Its successor, the FSB-2 or IRB Improved Ribbon Bridge MLC 70 has been chosen by the US Army as its new floating bridge to satisfy the needs of army engineers required by heavier combat vehicles.
Since 1977, EWK have been acting as main contractors of the Bundeswehr, providing them with the Folding Float Bridge. This piece of equipment is interoperable with the US Ribbon Bridge and has been redesigned basically. Same as the Ribbon Bridge, it is made of aluminium (FSB, Aluminium). For the Bundeswehr Folding Float Bridge there had been a series of requirements to be met: Change to use of metrical system; Improvements in the hydraulic systems of the ramp bays; Non-slip coating for the roadway surface; and Increased ease of handling of the bridge sections.
Replacement of bridge sections of the Bundeswehr FSB against elements of the US Ribbon Bridge and intercoupling are practical at any time. The Soviet steeltype Folding Float Bridge designated PMP that was used by Egyptian units to cross the Suez Canal in 1973 works based on the same principle. EWK deliver both Folding Float Bridges made of aluminium ("FSB, Alumin-ium") and of steel ("FSB, Steel").
Floating bridges for military purposes have been known since decades. There are numerous floating bridge systems existing using different materials. In most cases, buoyancy is - similar to floating docks - provided by floating hollow structures designated pontoons. For Folding Float Bridges they are described as bridge sections which are categorised into interior bays and ramp bays. Each bridge section comprises two inner and two outer pontoons that are connected to each other by joints and/or hinges. Thus, the bridge section becomes foldable and - assuming its typical W-shape - can be loaded on a bridge transport vehicle. Equipment qualified for use as bridge transport vehicles are cross-country lorries which offer a useful load of 7-10 t, are equipped with a special launching and retrieval system to let the bridge sections drop into the water and recover them when the mission is accomplished, and also have a single-axle trailer to carry the pertaining tugboats.