FltPlan.com said that there have been no glitches with general aviation pilots using its new pre-departure clearance (PDC) delivery system, which was rolled out in May, despite early concerns they would have difficulty interpreting PDCs. “There haven’t been any instances of pilot deviations based on general aviation pilots using our system,” said FltPlan.com president Ken Wilson. “Unlike the airlines, which have been plagued by pilot deviations because of pilots’ lack of understanding of [them].” PDCs are intended to reduce controller and pilot workload, delays in pilots receiving their clearances and radio congestion on clearance delivery frequencies as well as to avoid potential verbal instruction errors.