Horizon Air

Paragraph (g) The first sentence in the paragraph states “Within 30 days after the effective date of the AD, revise the maintenance program…” The sentence does not clearly state what maintenance program the FAA wants revised. Is it the operator maintenance program or the maintenance program in PSM 1-84-7? Do you want the operators to put the MRB task into their program and revise PSM 1-84-7 or just revise PSM 1-84-7? If it is the FAA’s intent to mandate a change to the operator’s maintenance program then the sentence should be change to “… revise the operator’s maintenance program…” The paragraph mandates implementation of task 323100-202 into the maintenance program but is silent on what procedures are used to accomplish the task. If it is the intent of the FAA to leave it up to the owner / operator to determine what instructions are to be used then that should be stated in the AD. Bombardier Maintenance Task Card Manual PSM1−84−7TC, task cards 000-32-720-710 and 000-32-730-710 exist for accomplishment of the task, however the task cards refer the technician to AMM 32-31-21-220-801 for accomplishment instructions. If it is the intent of the FAA to mandate instructions used to accomplish the task then that should be stated in the AD, along with the revision date of those instructions and sub tasks. Paragraph (g)(1)(2)(3) The requirements in the sub paragraphs do not take in to account any actions that may have been taken by operators to reduce the possibility of schedule interruptions caused by the up-lock hook wear. AMM task 32-31-21-220-801, ‘Detailed Dimensional Inspection of the MLG Up-lock Assembly’ is the task that Temporary Revision MRB-66 adds to the maintenance program. We would like the language in final rule to state that operators that have performed AMM task 32-31-21-220-801 prior to the effective date of the AD have met the requirements for paragraph (g)(1)(2)&(3). Paragraph (h) This paragraph provides instructions that may be used in lieu