Horizon Air

Paragraph (g), (h) & (i) The Bombardier service bulletin 84-27-57 referenced in this proposed rule making was issued on July 22, 2011. This service bulletin addresses the unsafe conditions that were known to exist at that time, but since that time, Bombardier and Parker Aerospace have taken an additional action to alleviate the unsafe condition. We would like to see this action added to the final rule as an acceptable method of compliance to address the unsafe condition Parker Aerospace, the manufacturer of the rudder feel trim unit part number 399500-1007, introduced an additional modification for RFTU serial number 0009 thru 0388. Service Bulletin 399500-27-003 dated April 19, 2012, provides additional actions to alleviate the unsafe conditions this proposed rule making addresses. RFTUs modified by Service Bulletin 399500-27-003 are identified by a suffix ‘B’ to the unit serial number. On July 12, 2012 Bombardier issue a new Service Bulletin 84-27-60 which recognizes Parker Service Bulletin 399500-27-003 as an acceptable method to alleviate the unsafe conditions. Paragraph (g), (h) & (i) of the final rule should be revised to allow use of RFTUs that have Suffix ‘B’ in addition to units with suffix ‘A’. Making this change will allow operators that have taken actions to incorporate post service bulletin 399500-27-003 suffix ‘B’ units into their fleet, to be in compliance with the proposed rule. If the FAA adopts this rule without recognizing the additional actions taken since Service Bulletin 84-27-57 was issued, it will require operators to request an alternate means of compliance once the final rule is issued to keep the suffix ‘B’ units in service. Paragraph (g) (2) (i) Paragraph (g) (2) (i) states … before further flight, replace the RFTU with a new RFTU in accordance with … The word new implies a zero time unit.(One that is new from the OEM). Operators should not be required to (see attached file for complete comment)