United Airlines

1. In proposed AD, the last paragraph in “Discussion” section and paragraphs (i)(1) and (i)(2) states "replace the affected THSA with a new THSA". It should change to "replace the affected THSA with a THSA, in accordance with the Accomplishment Instructions of Airbus Service Bulletin A320-27-1214, including Appendix 01, dated February 23, 2012”. UA believes that it is not necessary to replace the affected THSA with a brand new THSA, any THSA is inspected per SB and is determined to be type I corrosion should be good to be installed. 2. In paragraph (i)(3), for THSA with type II corrosion and passed integrity test, the proposed AD says to replace the THSA. We recommend to replace the ballscrew instead of replacing the whole THSA. 3. If item 2 above is not going to be accepted by FAA, then the recommendation in item 1 will apply to paragraph (i)(3) as well. 4. In paragraph (k) the proposed AD stated “If any corrosion type is found during any inspection”, operators need to report the findings to Airbus. Per Airbus SB A320-27-1214, type I corrosion is “no corrosion”. Therefore, AD should be changed to say only type II and III corrosion need to be reported. We believe there is no need to report type I as it is no corrosion. 5. In paragraph (l)(2), it should be more clear that only THSA’s with more than 20 year accumulated since first flight need to be inspected as required by paragraph (h) of the AD. 6. Question: base on paragraph (h), does it mean THSA’s won’t need to perform this AD requirement until they reach 20 years accumulated since the THSA’s first flight?