Before revision: upright=1.5|Underslung (lower-beam) launching gantry used for Skyline guideway construction (2015) A launching gantry (also called beam launcher, girder launcher, bridge building crane, and bridge-building machine , locally nicknamed the "Iron Monster" ) is a special-purpose mobile gantry crane used in bridge construction, specifically segmental bridges that use precast box girder bridge segments or precast girders in highway and high-speed rail bridge construction projects.
After revision: upright=1.5|Underslung (lower-beam) launching gantry used for Skyline guideway construction (2015) A launching gantry (also called bridge building crane, and bridge-building machine ) is a special-purpose mobile gantry crane used in bridge construction, specifically segmental bridges that use precast box girder bridge segments or precast girders in highway and high-speed rail bridge construction projects.