Airworthiness Directives; General Electric Aircraft Engines CT7 Series Turboprop Engines

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

The FAA is superseding an existing airworthiness directive (AD) for certain General Electric Aircraft Engines (GEAE) CT7 series turboprop engines. That AD currently requires propeller gearbox (PGB) oil filter impending bypass button (IBB) inspections, oil filter inspections, replacement of left-hand and right-hand idler gears at time of PGB overhaul, and replacement of certain serial number (SN) PGBs before accumulating 2,000 flight hours. This AD requires the same actions, and adds additional SNs of affected PGBs. This AD results from reports of PGBs equipped with certain gears that do not meet design specifications, resulting in the same failure addressed in the existing AD. We are issuing this AD to prevent separation of PGB left-hand and right-hand idler gears, which could result in uncontained PGB failure and internal bulkhead damage, possibly prohibiting the auxiliary feathering system from fully feathering the propeller on certain PGBs.

DATES:

This AD becomes effective May 11, 2004. The Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulations as of May 11, 2004. The Director of the Federal Register approved the incorporation by reference of certain other publications listed in the regulations as of April 24, 2003 (68 FR 13618, March 20, 2003).

ADDRESSES:

You can get the service information identified in this AD from General Electric Aircraft Engines, CT7 Series Turboprop Engines, 1000 Western Ave, Lynn, MA 01910; telephone (781) 594-3140, fax (781) 594-4805.

You may examine the AD docket, by appointment, at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA. You may examine the service information, by appointment, at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT:

Eugene Triozzi, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone (781) 238-7148; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

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 clarification will 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 that SB. 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 is included 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 sending a 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.

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:

2004-07-09 General Electric Aircraft Engines: Amendment 39-13553. Docket No. 99-NE-48-AD. Supersedes AD 2003-06-03, Amendment 39-13090.

Effective Date

(a) This AD becomes effective May 11, 2004.

Affected ADs

(b) This AD supersedes AD 2003-06-03, Amendment 39-13090.

Applicability

(c) This AD applies to General Electric Aircraft Engines (GEAE) CT7 series turboprop engines, with propeller gearboxes (PGBs) identified by serial number (SN) in Table 1 of GEAE CT7 Turboprop Service Bulletin (SB) CT7-TP S/B 72-0452, dated July 27, 2001, and Table 1 of GEAE CT7 Turboprop Alert Service Bulletin (ASB) CT7-TP S/B 72-A0466, dated April 17, 2003. These engines are installed on but not limited to SAAB 340 series airplanes.

Unsafe Condition

(d) This AD results from reports of PGBs equipped with certain gears that do not meet design specifications, resulting in the same failure addressed in the AD being superseded. We are issuing this AD to prevent separation of PGB left-hand and right-hand idler gears, which could result in uncontained PGB failure and internal bulkhead damage, possibly prohibiting the auxiliary feathering system from fully feathering the propeller on certain PGBs.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done.

(f) Inspect the PGB oil filter impending bypass button (IBB) for extension using the following schedule:

(1) Initially inspect within 50 hours time-in-service (TIS) after the effective date of this AD.

(2) Thereafter, inspect each operational day. The flight crew may inspect the PGB oil filter IBB for extension if maintenance personnel are not available.

(g) If the PGB oil filter IBB is extended, replace the oil filter and perform follow-on inspections, using paragraph 3.A of the Accomplishment Instructions of GEAE CT7 Turboprop SB CT7-TP S/B 72-0453, dated July 27, 2001.

(h) At the next return of the PGB to a CT7 turboprop overhaul facility after the effective date of this AD, replace left-hand and right-hand idler gears. Use the Accomplishment Instructions of GEAE CT7 Turboprop SB CT7-TP S/B 72-0452, dated July 27, 2001 to replace the gears.

(i) If the PGB is mated to a Hamilton Standard propeller and the left-hand and right-hand idler gears have not been replaced using the Accomplishment Instructions of GEAE CT7 Turboprop SB CT7-TP S/B 72-0452, dated July 27, 2001, replace the PGB before accumulating an additional 2,000 engine flight hours after April 24, 2003, the effective date of AD 2003-06-03.

PGB Oil Filter IBB Inspection, Authorization

(j) For GEAE CT7 series turboprop engines, in exception to the limitations imposed by § 43.3 of the Federal Aviation Regulations (14 CFR 43.3), a flight crew member holding at least a private pilot certificate may perform the inspections required by paragraph (f) of this AD. You must record completion of the inspections in the airplane records to show compliance with this AD, in accordance with §§ 43.9 and 91.417(a)(2)(v) of the Federal Aviation Regulations 14 CFR 43.9 and 14 CFR 91.417(a)(2)(v). You must also maintain the records as required by the applicable Federal Aviation Regulation.

Terminating Action

(k) Replacement of left-hand and right-hand idler gears using paragraph (h) of this AD, or replacement of the PGB using paragraph (i) of this AD constitutes terminating action to the repetitive inspections required by paragraph (f) of this AD.

Definition

(l) For the purpose of this AD, an operational day is defined as a day during which the airplane has flown for any reason.

Alternative Methods of Compliance

(m) The Manager, Engine Certification Office, has the authority to approve alternative methods of compliance for this AD if requested using the procedures found in 14 CFR 39.19.

Special Flight Permits

(n) Under 14 CFR 39.23, we are limiting the special flight permits for this AD by allowing the operation of an airplane that does not have more than one engine with a PGB oil filter IBB extended to a location where the requirements of this AD can be done.

Material Incorporated by Reference

(o) You must use the service information specified in Table 1 to perform the inspections and replacements required by this AD. The Director of the Federal Register approved the incorporation by reference of GEAE CT7 Turboprop SB CT7-TP S/B 72-0452, dated July 27, 2001, and GEAE CT7 Turboprop SB CT7-TP S/B 72-0453, dated July 27, 2001, as of April 24, 2003 (68 FR 13618, March 20, 2003). The Director of the Federal Register approves the incorporation by reference of GEAE CT7 Turboprop ASB CT7-TP S/B 72-A0466, dated April 17, 2003 in accordance with 5 U.S.C.552(a) and 1 CFR part 51. You can get copies from General Electric Aircraft Engines, CT7 Series Turboprop Engines, 1000 Western Ave, Lynn, MA 01910; telephone (781) 594-3140, fax (781) 594-4805. You may review copies at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC. Table 1 follows:

Related Information

(p) None.