The FAA proposed to amend 14 CFR Part 39 with a proposed AD. The proposed AD applies to certain GEAE CT7 series turboprop engines. We published the proposed AD in the Federal Register on March 20, 2003 (68 FR 13618). That action proposed to require PGB oil filter IBB inspections, oil filter inspections, replacement of left- hand and right-hand idler gears at time of PGB overhaul, and replacement of certain SN PGBs before accumulating 2,000 flight hours.
Comments
We provided the public the opportunity to participate in the development of this AD. We have considered the comments received.
Clarification of Applicability for AD Inspection Requirements
One commenter requests that we clarify paragraph (c), the applicability paragraph, to state that the inspection applies to all listed PGB serial numbers regardless of whether or not the propeller gearbox is mated to a Hamilton Standard propeller. The commenter states that making this clarificationwill prevent the AD from being misinterpreted as excluding inspections for PGBs mated to Hamilton Standard propellers.
We agree with the commenter that the AD applies to all CT7 engines with the identified PGBs installed. We do not agree, however, that additional changes to the applicability paragraph are needed or necessary. The applicability paragraph incorporates by reference a Table of affected PGB serial numbers contained in the General Electric Service Bulletins. The AD applies to any engine with a PGB listed in the Table regardless of whether the propeller gearbox is mated to a Hamilton Standard propeller or some other make of propeller. If the PGB is mated to a Hamilton Standard propeller, however, then the AD requires additional actions. These further actions do not imply that the AD is only applicable to engines with PGBs mated to Hamilton Standard propellers. The compliance section is written to be consistent with AD 2003-06-03, which this AD is superseding.
Clarification of the Term Operational Day
The same commenter requests that in paragraph (f)(2), the term "operational day" be replaced with "flight day". The commenter states that the daily inspection of the IBB should not be required on an airplane unless the airplane has been used for flight that day.
We agree that clarification is needed. A definition for "operational day" has been added to the compliance section, which states that an operational day is a day during which the airplane has flown for any reason.
Give Flight Crews Permission To Inspect the IBB
The same commenter requests that we give flight crews permission to inspect the IBB for extension at remote stations where maintenance personnel are not available. This would relieve the burden of sending maintenance personnel to a remote station to do an inspection of the IBB, when the airplane is at that remote station longer than one day. The commenter understands that if the IBB is found extended, maintenance personnel would have to perform the other AD requirements.
We agree that flight crews should be allowed to perform the IBB inspection if the maintenance personnel are not available. If the IBB is found extended, however, maintenance personnel would have to perform the other AD requirements. Paragraph (f)(2) has been rewritten to allow flight crews to inspect the IBB.
No Terminating Action for Paragraphs (h) and (i)
One commenter requests that paragraphs (h) and (i) be revised, as there is no terminating action in these paragraphs for PGBs listed in Table 1 of Service Bulletin (SB) 72-466. The commenter further states that SB 72-452 provides terminating action only for PGBs listed in SB 72-452 and not PGBs listed in SB 72-466.
We do not agree. The terminating action paragraph specifically requires replacement of idler gears using the Accomplishment Instructions of SB 72-452 and does not limit this terminating action to the serial numbers listed in the effectivity of thatSB. The accomplishment instructions for replacement of idler gears are the same regardless of the gear serial numbers being replaced. Based on this, replacing the gears using the accomplishment instructions of SB 72-452 is an acceptable terminating action.
Conclusion
We have carefully reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.
Changes to 14 CFR Part 39--Effect on the AD
On July 10, 2002, we issued a new version of 14 CFR part 39 (67 FR 47998, July 22, 2002), which governs the FAA's AD system. That regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance. The material previously was included in each individual AD. Since the material isincluded in 14 CFR part 39, we will not include it in future AD actions.
Regulatory Findings
We have determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.
For the reasons discussed above, I certify that this AD:
(1) Is not a "significant regulatory action" under Executive Order 12866;
(2) Is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and
(3) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.
We prepared a summary of the costs to comply with this AD and placed it in the AD Docket. You may get a copy of this summary by sendinga request to us at the address listed under ADDRESSES. Include "AD Docket No. 99-NE-48-AD" in your request.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration amends 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
39.13 [Amended]
2. The FAA amends 39.13 by removing Amendment 39-13090 (68 FR 13618, March 20, 2003) and by adding a new airworthiness directive, Amendment 39-13553, to read as follows: