Landings are guided by a Tactical Automatic Landing System, developed by the Sierra Nevada Corporation, which consists of a ground-based micro-millimeter wavelength radar and a transponder carried on the aircraft. Once on the ground, a tailhook mounted on the aircraft catches an arresting wire connected to two disk brake drums which can stop the aircraft in less than . The aircraft is part of a larger system which currently uses the M1152-series of Humvees for ground transport of all ground and air equipment. A Shadow 200 system consists of four aircraft, three of which are transported in the Air Vehicle Transporter (AVT). The fourth is transported in a specially designed storage container to be used as a spare. The AVT also tows the launcher. The AVT Support Vehicle and trailer contain extra equipment to launch and recover the aircraft, such as the Tactical Automatic Landing System. Maintenance equipment for the aircraft is stored in the Maintenance Section Multifunctional (MSM) vehicle and trailer as well as the M1165 MSM Support Vehicle and its associated trailer. Two Humvee-mounted Ground Control Stations (GCS), also part of the Shadow 200 system, control the aircraft in flight. Each station has an associated Ground Data Terminal (GDT), which takes commands generated by the GCS and modulates them into radio waves received by the aircraft in flight. The GDT receives video imagery from the payload, as well as telemetry from the aircraft, and sends this information to the GCS. A trailer, towed by the M1165 GCS support vehicle, carries the GDT and houses a 10 kW Tactical Quiet Generator to provide power for its associated GCS. The Shadow 200 system also includes a Portable Ground Control Station (PGCS) and Portable Ground Data Terminal (PGDT), which are stripped-down versions of the GCS and GDT designed as a backup to the two GCSs. A fielded Shadow 200 system requires 22 soldiers to operate it. Army modelling indicates that crew workload is highest at takeoff, and second-highest at landing. The Shadow is restricted from operating in bad weather conditions, not being meant to fly through rain and with sensors that cannot see through clouds. By July 2007, the Shadow platform accumulated 200,000 flight hours, doubling its previous record of 100,000 hours in 13 months. The system then surpassed 300,000 flight hours in April 2008, and by May 2010, the Shadow system had accumulated over 500,000 flight hours. As of 2011, the Shadow had logged over 709,000 hours.