FAA official Keith Noles has clarified the cost estimates published in last Monday's airworthiness directive affecting some Piper aircraft. According to Noles: "An owner/operator could choose one of two paths, either inspection or replacement. The key here is that the disassembly/removal and reassembly/installation is the bulk of the cost in any scenario, and it would not be repeated in any one event. Here are the possible scenarios: 1. Disassemble, inspect with no discrepancies, reassemble. Cost estimate is $1020. 2. Disassemble, inspect with discrepancy requiring replacement. Cost estimate is $1592. 3. Disassemble, do not inspect, replace/reassemble. Cost estimate is $1592." AVweb story last Monday read, "If the assembly needs to be replaced, it would cost another $1,600," but that amount should be $572.