Richard Rupslauskas

Para 2. (h): It is stated here that “A review of airplane maintenance records is acceptable in lieu of this inspection if the part number of the ADG can be conclusively identified from that review”. Since Service Bulletins 601R-24-127 and ERPS10AG-24-5 are serial number specific, it is necessary to review records for serial numbers as well to conclude whether or not any affected units are part of the airlines inventory. Throughout the NPRM, reference is made to the symbol “24-5”. The NPRM is putting too much emphasis on this marking. While confirming “24-5”on the unit’s data plate may be appropriate for corporate / small fleet type operators, FAR 121 operators have approved record keeping programs that make, in this case, identifying whether or not “24-5” is on the data plate redundant and unnecessary. Marking “24-5” on the unit does not make that unit any safer and should not be a requirement of the directive. The operator’s record keeping system has been approved to sufficiently assure compliance. Consideration should be given to eliminate reference to this marking, but specifically in Para 2. (j), it is irrelevant that operators be mandated to not install units without “24-5” marked on the unit. The marking is irrelevant to operators with approved record keeping systems. Lack of the marking “24-5” should not be sufficient reason to remove an aircraft from revenue service. The operators have accomplished many component modifications without the requirement to have a marking applied. Once again, it is the operator’s record keeping system that is required to show method of compliance with Airworthiness Directives. In this case (Para 2. (j), suggested wording would be “… no person may install on an airplane, a replacement or spare ADG… that has not been modified per the instructions of ERPS10AG-24-5.” Precedent has been set in many other ADs that affect component installation. Para 2. (k): It is stated here that “… this AD requires the inspection be done on all airplanes”. Two points: 1) “All airplanes”, as used here, is confusing. What is meant by all airplanes? If “all airplanes” is meant all airplanes listed in the effectivity of the SBs, the AD should be aircraft serial number specific. Which leads me to item 2), this AD may be more appropriate to be classified as an appliance AD. Doubting that will happen, when describing the effectivity of the AD, it should also include a statement to ensure compliance on all units in inventory. Affected units may not be installed on aircraft, but rather in Stores (spare inventory).