The draglines are large, self-propelled pieces of surface mining equipment used to pull large drag buckets across the ground to remove soil overburden and expose the underlying coal beds. The Marion 7400 and 7500 were produced by the Marion Power Shovel Company of Marion, Ohio, and purchased by the PBS Coal Company of Friedens, PA, where they operated at their Shanksville, PA mining site. Their position, overlooking the crash site of United Airlines Flight 93 and the proposed National Park Service Flight 93 Memorial, raised questions concerning their significance to the site. They were assessed in order to determine their stability, on-going issues of maintenance and long term preservation, and visitor safety. Eye witness accounts on the morning of September 11, 2001, suggested that the aircraft's path, just prior to impact, traveled between the upright booms of these two draglines; however, later evidence dispelled the accuracy of this account. The American flag, placed atop the larger Marion 7500, was one of the first displays of patriotism and tribute to the passengers of Flight 93.
The Marion 7500 Dragline was in poor and unstable condition due to years of neglect and exposure to the harsh environment of the western Pennsylvania highlands since surface mining was completed in 1995. The painted steel control house, rotating platform, and boom are in poor condition due to severe and active corrosion. The paint has blistered and scaled in many areas as a result of corrosion of the iron substrate. The roof panels are badly deformed causing rain water to collect and eventually infiltrate the interior of the dragline control house. The 22 cubic yard bucket, resting in the dirt, is partially filled with water, dirt and organic debris. The braided steel operating cables, while appearing to remain sound, have not been maintained or greased for many years allowing water to penetrate their core. Failure of these cables could allow the boom to collapse. The interior of the dragline, which retains much of its original machinery, is in very poor condition. All painted surfaces are covered with flaking and scaling paint; active iron corrosion is observed overall. Continual water infiltration allows the interior to remain damp for extended periods of time. Debris, old clothing, and operational manuals, cover much of the floor and cabinet interiors. The pilot house windows are broken and large sections of glass / plexiglass are missing. Small birds and animals appear to inhabit the interior spaces of the dragline leaving accumulations of guano and nesting materials.
As conclusive evidence became available concerning the flight path of United Flight 93, the National Park Service and the Flight 93 National Memorial committee decided that the Marion 7400 and 7500 draglines were not an integral part of the site and were transferred back to the original owners of the equipment.