Dan P. Johnson

The reduction of the hourly limit may be acceptable provided there is evidence supporting it. The Proposed AD document states the ?Based on full scale fatigue tests the life limit has been extended but the TBO reduced?. I would like to see the actual test results that prove a 5 year calendar limit is warranted. Please notice that the current Chapter 4 component entry for this actuator has no calendar limitation. These actuators are overhauled in the U.S. by Derco Repair services inc. in Milwaukee WI. I contacted this Repair Station for a quote to overhaul one of these last year. I was told that at that time the average to date had been around $4500.00. I was also told that due to a proprietary agreement with Pilatus they would not accept direct requests for overhaul and only Pilatus could provide service. This is a common practice of Pilatus to control U.S. parts distribution. I understand that the FAA is not concerned with costs incurred by operators in the interest of safety. My concern is when they assist in the gouging of American operators by agreeing to an unsubstantiated calendar limit. My opinion is that the hourly TBO reduction is sufficient for Part 91 operators.