Before revision: upright=1.5| Launching gantry used for Honolulu Rail Transit guideway construction (2015) A launching gantry ( described also by other terms including 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 .
After revision: upright=1.5| Underslung (lower-beam) launching gantry used for Honolulu Rail Transit 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 .