Airworthiness directives: Aerospatiale,
[Federal Register: October 26, 1999 (Volume 64, Number 206)]
[Proposed Rules]
[Page 57602-57605]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr26oc99-25]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-NM-240-AD]
RIN 2120-AA64
Airworthiness Directives; Aerospatiale Model ATR72 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Supplemental notice of proposed rulemaking; reopening of comment period.
SUMMARY: This document revises an earlier proposed airworthiness directive (AD), applicable to certain Aerospatiale Model ATR72 series airplanes, that would have required initial and repetitive inspections to detect fatigue cracking in certain areas of the fuselage, and corrective actions, if necessary. That proposal was prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. This new action revises the proposed rule by correcting an omission of the compliance time for accomplishment of the initial inspection for certain airplanes. The actions specified by this new proposed AD are intended to prevent fatigue cracking of the fuselage and the passenger and service doors, which could result in reduced structural integrity of the airplane.
DATES: Comments must be received by November 26, 1999.
ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-NM-240-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal holidays.
The service information referenced in the proposed rule may be obtained from Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 03, France. This information may be examined at the FAA, Transport Airplane Directorate,
[[Page 57603]]
1601 Lind Avenue, SW., Renton, Washington.
FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2110; fax (425) 227-1149.
SUPPLEMENTARY INFORMATION:
Comments Invited
Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this notice may be changed in light of the comments received.
Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filedin the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: ``Comments to Docket Number 98-NM-240-AD.'' The postcard will be date stamped and returned to the commenter.
Availability of NPRMs
Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-NM-240-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.
Discussion
A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to add an airworthiness directive (AD), applicable to certain Aerospatiale Model ATR72 series airplanes, was published as a notice of proposed rulemaking (NPRM) in the Federal Register on January 5, 1999 (64 FR 438). That NPRM would have required initial and repetitive inspections to detect fatigue cracking in certain areas of the fuselage, and corrective actions, if necessary. That NPRM was prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. That condition, if not corrected, could result in fatigue cracking of the fuselage and the passenger and service doors, which could result in reduced structural integrity of the airplane.
Actions Since Issuance of Previous Proposal
Due consideration has been given to the comments received in response to that NPRM.
Omission of Compliance Time
Two commenters state that paragraph (a) of the proposed AD does not address a time frame for accomplishment of the proposed actions. Both commenters note that the compliance deadline in the service bulletin is 27,000 total flight cycles, and assume that the FAA's intent was to follow that compliance time.
The FAA acknowledges that paragraph (a) of the proposed AD does not specify a compliance time. It was the FAA's intent to follow the same compliance time as that specified in the service bulletin; the compliance time was inadvertently omitted from the NPRM. This error has been corrected, and, due to this omission, the revised rule will be issued as a supplemental NPRM.
Conclusion
Since this change expands the scope of the originally proposed rule, the FAA has determined that it is necessary to reopen the comment period to provide additional opportunity for public comment.
Request To Allow Latest Service Bulletin Revisions
One commenter states that for paragraphs (b) and (c), respectively, ATR Service Bulletins ATR72-53-1013 and ATR72-53-1019, both Revision 3, were issued January 22, 1999. The commenter requests that the AD reference Revision 3 of both of these bulletins instead of Revision 2, as currently referenced. Revision 3 of the service bulletins provides a compliance time of 36,000 total flight cycles, which is consistent with the French AD and this NPRM.
The FAA concurs with the commenter's request. Revisions 2 and 3 of the service bulletins mentioned above are technically equivalent. This supplemental NPRM will be revised to reference Revision 3; however, Note 2 is revised to also allow compliance with Revision 2 prior to the effective date of the AD.
Cost Impact
The FAA estimates that 39 airplanes of U.S. registry would be affected by this proposed AD.
For airplanes identified in Avions de Transport Regional Service Bulletin ATR72-53-1018 (14 U.S.-sregistered airplanes), it would take approximately 250 work hours per airplane to accomplish the proposed actions, at an average labor rate of $60 per work hour. Required parts would cost approximately $9,880 per airplane. Based on these figures, the cost impact of these actions proposed by this AD on U.S. operators is estimated to be $348,320, or $24,880 per airplane.
For airplanes identified in Avions de Transport Regional Service Bulletin ATR72-52-1013, Revision 2 (2 U.S.-registered airplanes), it would take approximately 3 work hours per airplane to accomplish the proposed actions, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of these actions proposed by this AD on U.S. operators is estimated to be $360, or $180 per airplane.
For airplanes identified in Avions de Transport Regional Service Bulletin ATR72-52-1019, Revision 2 (2 U.S.-registered airplanes), it would take approximately 100 work hours per airplane to accomplish the proposed actions, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of these actions proposed by this AD on U.S. operators is estimated to be $12,000, or $6,000 per airplane.
For airplanes identified in Avions de Transport Regional Service Bulletin ATR72-52-1028 (2 U.S.-registered airplanes), it would take approximately 5 work hours per airplane to accomplish the proposed actions, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of these actions proposed by this AD on U.S. operators is estimated to be $600 or $300 per airplane, per inspection cycle.
For airplanes identified in Avions de Transport Regional Service Bulletin ATR72-52-1033, and ATR72-52-1029, Revision 1 (2 U.S.- registered airplanes), it would take approximately 145 work hours per airplane to accomplish the proposed door stop fitting replacement, at an average labor rate of $60 per work hour. Required parts would be provided by the manufacturer at no cost to the operators. Based on these figures, the cost impact of the stop fittings replacement proposed by this AD on
[[Page 57604]]
U.S. operators is estimated to be $17,400 or $8,700 per airplane.
For airplanes identified in Avions de Transport Regional Service Bulletin ATR72-53-1021, Revision 1 (2 U.S.-registered airplanes), it would take approximately 30 work hours per airplane to accomplish the proposed actions, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of these actions proposed by this AD on U.S. operators is estimated to be $3,600, or $1,800 per airplane.
For airplanes identified in Avions de Transport Regional Service Bulletin ATR72-53-1014, Revision 2 (2 U.S.-registered airplanes), it would take approximately 8 work hours per airplane to accomplish the proposed actions, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of these actions proposed by this AD on U.S. operators is estimated to be $960, or $480 per airplane.
For airplanes identified in Avions de Transport Regional Service Bulletin ATR72-53-1020 (14 U.S.-registered airplanes), it would take approximately 6 work hours per airplane to accomplish the proposed actions, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of these actions proposed by this AD on U.S. operators is estimated to be $5,040, or $360 per airplane.
The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.
Regulatory Impact
The regulations proposed herein would not have substantial direct effects 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. Therefore, in accordance with Executive Order 12612, it is determined that this proposal would not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.
For the reasons discussed above, I certify that this proposed regulation (1) is not a ``significant regulatory action'' under Executive Order 12866; (2) is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, 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. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:
PART 39--AIRWORTHINESS DIRECTIVES
-
The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
-
Section 39.13 is amended by adding the following new airworthiness directive:
Aerospatiale: Docket 98-NM-240-AD.
Applicability: Model ATR72 series airplanes, certificated in any category; listed in the following Avions de Transport Regional Service Bulletins:
‹bullet› ATR72-52-1018, dated May 18, 1995;
‹bullet› ATR72-53-1013, Revision 2, dated March 22, 1993;
‹bullet› ATR72-53-1019, Revision 2, dated October 15, 1996;
‹bullet› ATR72-52-1028, dated July 5, 1993;
‹bullet› ATR72-52-1033, dated April 28, 1995;
‹bullet› ATR72-52-1029, Revision 1, dated November 16, 1994;
‹bullet› ATR72-53-1021, Revision 1, dated February 20, 1995;
‹bullet› ATR72-53-1014, Revision 2, dated October 15, 1992; and
‹bullet› ATR72-53-1020, dated October 6, 1992.
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (i) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
Compliance: Required as indicated, unless accomplished previously.
To prevent fatigue cracking of the fuselage and the passenger and service doors, which could result in reduced structural integrity of the airplane, accomplish the following:
(a) For airplanes on which Aerospatiale Modification 03191 (reference Avions de Transport Regional Service Bulletin ATR72-52- 1018, dated May 18, 1995) has not been accomplished: Prior to the accumulation of 27,000 total flight cycles, or within 30 days after the effective date of this AD, whichever occurs later, perform a preliminary inspection of the existing fasteners to determine if the fasteners are out of tolerance in accordance with paragraph 2.C.(1) of the Accomplishment Instructions of Avions de Transport Regional Service Bulletin ATR72-52-1018, dated May 18, 1995. Depending on the results of the inspection, prior to further flight, accomplish the requirements in paragraphs (a)(1) and (a)(2), or (a)(2) and (a)(3), of this AD, as applicable, as specified by paragraph 2.C.(1) of the service bulletin.
(1) Remove the fasteners and inspect the fastener holes to determine if they are out of tolerance or cracking, in accordance with Part A of the Accomplishment Instructions of the service bulletin. Perform a visual inspection of the holes for correct tolerance, and a high frequency eddy current (HFEC) inspection for cracking.
(i) If any discrepancy is detected, prior to further flight, repair in accordance with Part C of the Accomplishment Instructions of the service bulletin.
(ii) If no discrepancy is detected, prior to further flight, replace the cargo compartment door hinges with new hinges in accordance with Part A of the Accomplishment Instructions of the service bulletin.
(2) Remove the existing fasteners and inspect the fastener holes for correct tolerance in accordance with Part B of the Accomplishment Instructions of the service bulletin.
(i) If any discrepancy is detected, prior to further flight, repair in accordance with a method approved by the Manager, International Branch, ANM-116, Transport Airplane Directorate; or the Direction Generale de l'Aviation Civile (DGAC) or its delegated agent.
(ii) If no discrepancy is detected, prior to further flight, replace the cargo compartment door hinges with new hinges in accordance with Part B of the Accomplishment Instructions of the service bulletin.
(3) Remove the existing fasteners, repair, and replace the cargo compartment door hinges with new hinges in accordance with Part C of the Accomplishment Instructions of the service bulletin.
(b) For airplanes having serial numbers 108 through 210 inclusive: Prior to the accumulation of 36,000 total flight cycles, or within 30 days after the effective date of this AD, whichever occurs later, perform a one-time visual inspection to determine if rivets are installed in the key holes located on main frames 25 and 27 of the fuselage, between stringers 14 and 15, in accordance with Avions de Transport Regional Service Bulletin ATR72-53-1013, Revision 3, dated January 22, 1999.
(1) If all rivets are installed, no further action is required by paragraph (b) of this AD.
(2) If any rivet is missing, prior to further flight, perform an eddy current inspection of the affected key holes to detect cracks, in accordance with the service bulletin.
[[Page 57605]]
(i) If no crack is detected during the inspection required by paragraph (b)(2) of this AD, prior to further flight, install rivets in all affected key holes, in accordance with the service bulletin. If installation of rivets is not possible, prior to further flight, repair in accordance with a method approved by the Manager, International Branch, ANM-116; or the DGAC (or its delegated agent).
(ii) If any crack is detected during the inspection required by paragraph (b)(2) of this AD, prior to further flight, repair in accordance with a method approved by the Manager, International Branch, ANM-116; or the DGAC (or its delegated agent).
(c) For airplanes having serial numbers 108 through 207 inclusive: Prior to the accumulation of 36,000 total flight cycles, or within 30 days after the effective date of this AD, whichever occurs later, perform a one-time visual inspection to determine if rivets are installed in the tooling and key holes located on the standard frames of the fuselage, in accordance with Avions de Transport Regional Service Bulletin ATR72-53-1019, Revision 3, dated January 22, 1999.
(1) If all rivets are installed, no further action is required by paragraph (c) of this AD.
(2) If any rivet is missing, prior to further flight, perform a visual inspection of the affected tooling and key holes to detect cracks, in accordance with the service bulletin.
(i) If no crack is detected during the inspection required by paragraph (c)(2) of this AD, prior to further flight, install new rivets in all affected tooling and key holes, in accordance with the service bulletin.
(ii) If any crack is detected during the inspection required by paragraph (c)(2) of this AD, prior to further flight, repair in accordance with a method approved by the Manager, International Branch, ANM-116; or the DGAC (or its delegated agent).
(d) For airplanes on which Aerospatiale Modification 03775 (reference Avions de Transport Regional Service Bulletin ATR72-52- 1029, Revision 1, dated November 16, 1994) or Aerospatiale Modification 03776 (reference Avions de Transport Regional Service Bulletin ATR72-52-1033, dated April 28, 1995) has not been accomplished: Prior to the accumulation of 12,000 total flight cycles, or within 30 days after the effective date of this AD, whichever occurs later, perform an eddy current inspection to detect cracks in the plug door stop fittings of the forward and aft passenger and service doors, in accordance with Avions de Transport Regional Service Bulletin ATR72-52-1028, dated July 5, 1993.
(1) If no crack is detected, repeat the eddy current inspection required by paragraph (d) of this AD thereafter at intervals not to exceed 6,000 flight cycles.
(2) If any crack is detected, prior to further flight, replace the cracked stop fittings with new, improved fittings, in accordance with Avions de Transport Regional Service Bulletin ATR72-52-1033, dated April 28, 1995, or ATR72-52-1029, Revision 1, dated November 16, 1994; as applicable. Accomplishment of the replacement constitutes terminating action for the repetitive inspection requirements of paragraph (d)(1) of this AD for that fitting.
(e) For airplanes on which Aerospatiale Modification 03775 or Aerospatiale Modification 03776 has not been accomplished: Prior to the accumulation of 18,000 total flight cycles, or within 30 days after the effective date of this AD, whichever occurs later, replace the plug door stop fittings of the forward and aft passenger and service doors with new, improved fittings, in accordance with Avions de Transport Regional Service Bulletin ATR72-52-1033, dated April 28, 1995; or ATR72-52-1029, Revision 1, dated November 16, 1994; as applicable. Accomplishment of the replacement constitutes terminating action for the repetitive inspection requirements of paragraph (d)(1) of this AD.
(f) For airplanes on which Aerospatiale Modification 02986 (reference Avions de Transport Regional Service Bulletin ATR72-53- 1021, Revision 1, dated February 20, 1995) has not been accomplished: Prior to the accumulation of 18,000 total flight cycles, or within 30 days after the effective date of this AD, whichever occurs later, perform a one-time eddy current inspection to detect cracks in the rivet holes of the door surround corners of the forward and aft passenger and service doors, in accordance with Avions de Transport Regional Service Bulletin ATR72-53-1021, Revision 1, dated February 20, 1995.
(1) If no crack is detected during the inspection required by paragraph (f) of this AD, prior to further flight, modify the rivet holes, and replace the door surround corners with modified corners, in accordance with the service bulletin.
(2) If any crack is detected during the inspection required by paragraph (f) of this AD, prior to further flight, repair and modify in accordance with a method approved by the Manager, International Branch, ANM-116; or the DGAC (or its delegated agent).
(g) For airplanes on which Aerospatiale Modification 02397 (reference Avions de Transport Regional Service Bulletin ATR72-53- 1014, Revision 2, dated October 15, 1992) has not been accomplished: Prior to the accumulation of 12,000 total flight cycles, or within 30 days after the effective date of this AD, whichever occurs later, perform a one-time eddy current inspection to detect cracks of the rivet holes located on the left and right sides of external stringer 4 at frames 24 and 28 of the fuselage, in accordance with Avions de Transport Regional Service Bulletin ATR72-53-1014, Revision 2, dated October 15, 1992.
(1) If no crack is detected during the inspection required by paragraph (g) of this AD, prior to further flight, install reinforcement angles on the left and right sides of external stringer 4 at frames 24 and 28 of the fuselage, in accordance with the service bulletin.
(2) If any crack is detected during the inspection required by paragraph (g) of this AD, prior to further flight, repair in accordance with a method approved by the Manager, International Branch, ANM-116; or the DGAC (or its delegated agent).
(h) For airplanes on which Aerospatiale Modification 03185 (reference Avions de Transport Regional Service Bulletin ATR72-53- 1020, dated October 6, 1992) has not been accomplished: Prior to the accumulation of 12,000 total flight cycles, or within 30 days after the effective date of this AD, whichever occurs later, perform a one-time eddy current inspection to detect cracks of the rivet holes located on stringer 11 of frame 26 of the fuselage, in accordance with Avions de Transport Regional Service Bulletin ATR72-53-1020, dated October 6, 1992.
(1) If no crack is detected during the inspection required by paragraph (h) of this AD, prior to further flight, install doublers and stringer clips on the left and right sides on stringer 11 of frame 26 of the fuselage, in accordance with the service bulletin.
(2) If any crack is detected during the inspection required by paragraph (h) of this AD, prior to further flight, repair in accordance with a method approved by the Manager, International Branch, ANM-116; or the DGAC (or its delegated agent).
Note 2: Inspections and repairs accomplished prior to the effective date of this AD in accordance with Avions de Transport Regional Service Bulletins ATR72-53-1013, dated June 10, 1991, or Revision 1, dated June 12, 1992, or Revision 2, dated March 22, 1993; ATR72-53-1019, dated May 13, 1993, or Revision 1, dated November 11, 1994, or Revision 2, dated October 15, 1996; ATR72-52- 1029, dated July 20, 1994; or ATR72-53-1014, Revision 1, dated June 30, 1992; are considered acceptable for compliance with the applicable actions specified in this amendment.
Alternative Methods of Compliance
(i) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, International Branch, ANM-116. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, International Branch, ANM-116.
Note 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116.
(j) Special flight permits may be issued in accordance with Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.
Note 4: The subject of this AD is addressed in French airworthiness directive 92-046-012(B)R4, dated November 5, 1997.
Issued in Renton, Washington, on October 20, 1999. N.B. Martenson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 99-27939Filed10-25-99; 8:45 am]
BILLING CODE 4915-13-U
