The New York, Susquehanna and Western Railway (NYSW), also known as the ‘Susquehanna,’ was formed in 1881 with the task of hauling coal from the Pennsylvanian Northern coalfield to the bustling New York metropolis of that age. Its 500 miles of track cross the northeastern states of New York, Pennsylvania and New Jersey, following the route of the historic Delaware River and, at times, traversing that fast-flowing state boundary on mighty steel bridges.
A scant few miles out of the sleepy New York town of Narrowsburg, one such structure emerges from the mixed forest banks and gleams rust red in the light reflected from the river’s rippling surface. Built in 1904 with masonry piers, vast steel girders and a series of towering metal truss-works, the Tusten 2 Railroad bridge (CYNK #9 or NYSW 117.76 for the bridgehunters.com fans) carries nightly freight trains between the Shohola and Narrows Control Points (moving more than one million gross tons annually). Such a task means that, for over a century, this solid monolith has needed to be kept in tremendous condition, with regular inspections and uniquely skilled repairs.
But times change, and in the first week of May the whistling breeze through the steel-work was joined by a steady whir of carbon fiber blades and the repetitive click of camera shutters. Railroad Bridge Inspectors (RBIs in the parlance) activated a new tool to check the state of every pin, chord, bearing and stringer that work in harmony to hold the track high off the water-line: an unmanned aerial vehicle, or drone.
Two teams of trained and certified small UAV (Unmanned Aerial Vehicle) operators came together after weeks of careful planning, site surveys, shot list preparations and rail safety briefs to fly a complete, detailed inspection of the Tusten Bridge’s three through-truss spans and one through-plategirder span. Unmanned Experts, a UAS training and services company based in Colorado, took several thousand HD photos plus videos of every side of the bridge deck, each pier and abutment, and the rail approaches. Media Wing (dba AirShark), a New Hampshire-based team of specialist UAV pilots, brought a uniquely modified drone with a “look up” capability to expertly photograph the state of the girders and ties underneath the decking, a challenging task given the restricted flying area and the deep shadows beneath the bridge.
Over two days of excellent spring weather, the teams worked hand-in-glove with NYSW track experts, RBIs and rail crews to document the condition of the bridge. Finally, the railroad representatives arranged a “load test” for the bridge. The UAV pilots positioned their drones within feet of the steel trusses and girders to record every movement of the structure as the railroad ran a locomotive and a loaded 286k tank car back and forth over the bridge.
Rick Howard, Assistant Chief Engineer at the NYSW, participated in the inspection and said, “We believe that drones will have a role in future bridge inspections, and welcomed the opportunity to see what they can do to improve inspection efficiency and safety, while still gathering the required information.”
Having taken over 2500 detailed photographs and videos representing 60 gigabytes of information, the processing, naming and assessment of all the data provided the final challenge to the crews. Back in their offices and thoroughly de-ticked (just one of the hazards of this fieldwork), the UAV teams followed a rigorous process to review the images and identify locations on the structure that needed highlighting in a detailed, federally-compliant CFR/FRA 237 report.
This was the 8th railroad bridge on which Unmanned Experts has completed aerial inspections, which it performs on infrastructure targets in addition to running training courses in the art, science and techniques of completing complex inspection projects. And Unmanned Experts’ teaming with AirShark worked out so well that several joint projects are already in advanced planning stages. Said Unmanned Experts’s CEO, Keven Gambold, to Media Wing / Airshark’s CEO, Fred Depuy, whilst on the track, “We have the same ethics, professionalism, and thirst to bring drone inspections into the mainstream. It’s a pleasure working side-by-side.”