AD 98-06-25

This amendment adopts a new airworthiness directive (AD) that applies to Fairchild Aircraft Inc. (Fairchild) Models SA226-AT, SA226-TC, SA227-AC, and SA227-AT airplanes. This action would require inspecting the cargo door lower belt frames at the cargo latch receptacles for cracks in the belt frames, repairing any cracks, and reinforcing the cargo door lower belt frames by installing doublers. The AD is the result of a decompression incident during flight caused by fatigue at the bottom of the cargo door on a Fairchild Model SA226-TC. The actions specified by this AD are intended to prevent the failure of the cargo door in flight, which could cause decompression injuries to passengers and substantial structural damage to the airplane.

Final rule

98-06-25 FAIRCHILD AIRCRAFT INC.: Amendment 39-10403; Docket No. 96-CE-68-AD.

Applicability: The following models and serial numbered airplanes, certificated in any category.

Models
Serial Numbers
SA226-AT
AT001 through AT074
SA226-TC
TC201 through TC419
SA227-AC
AC406, AC415, AC416, AC420 through AC456, AC458
through AC469, and AC471 through AC478
SA227-AT
AT423 through AT469

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 (e) 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 within the body of this AD, unless already accomplished.

To prevent failure of the cargo door in flight, which, if not corrected, could cause decompression injuries to passengers and substantial structural damage to the airplane, accomplish the following:

(a) Within the next 500 hours time-in-service (TIS) after the effective date of this AD, inspect the cargo door lower belt frames at the cargo latch receptacles for cracks in accordance with Part A of the ACCOMPLISHMENT INSTRUCTIONS section in Fairchild Aircraft SA226 Series Service Bulletin (SB) No. 226-53-007, Issued: May 7, 1981; Revised: February 17, 1992, or Fairchild Aircraft SA227 Series SB No. 227-53-003, Issued: January 29, 1986; Revised: February 13, 1986, whichever is applicable.

(b) If cracks are found during the inspectionrequired in paragraph (a) of this AD, prior to further flight, accomplish the following:

(1) For belt frames located at Fuselage Station (F.S.) 438.060 and F.S. 491.060, repair the belt frame by installing angle part number (P/N) 27-22206-009 or P/N 27-22206-010, in accordance with the Fairchild Aircraft SA226/227 Structural Repair Manual (SRM), Section 53-90-20, Initial Issue: March 1, 1983, Revision 24, dated August 27, 1997; or, Fairchild Aircraft Approved Repair Procedure (ARP) 53-30-9701, dated July 28, 1997. The reinforcement doublers (P/N 27-22206-007 and -008) are also needed together with this repair.

(2) For belt frames located at F.S. 454.501, F.S. 455.726, F.S. 473.392, and F.S. 474.657, replace all four belt frames with new design frames, P/N 27-22207-008, 27-22208-005, 27-22208-005, and 27-22207-007, respectively, in accordance with the Fairchild Aircraft SA226/227 SRM, Section 53-90-20, Initial Issue: March 1, 1983, Revision 24, dated August 27, 1997; or,Fairchild Aircraft ARP 53-30-9701, dated July 28, 1997. No reinforcement doublers are needed for these four new design belt frames.

(c) If no cracks are found in all six belt frames during the inspection required by paragraph (a) of this AD, install reinforcement doublers in all six belt frames within 500 hours TIS from the initial inspection, in accordance with Part B of the ACCOMPLISHMENT INSTRUCTIONS of Fairchild Aircraft SA226 Series Service Bulletin (SB) No. 226-53-007, Issued: May 7, 1981; Revised: February 17, 1992, or Fairchild Aircraft SA227 Series SB No. 227-53-003, Issued: January 29, 1986; Revised: February 13, 1986, whichever is applicable.

(d) Special flight permits may be issued in accordance with sections 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.

(e) An alternative method of compliance or adjustment of the initial or repetitive compliance time that provides an equivalent level of safety may be approved by the Manager, Fort Worth Airplane Certification Office, 2601 Meacham Boulevard, Fort Worth, Texas 76193-0150. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Fort Worth Airplane Certification Office.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Manager, Fort Worth Airplane Certification Office.

(f) The inspections and modifications required by this AD shall be done in accordance with the following service information:

Fairchild Aircraft Corporation SA227 Series Service Bulletin No. 227-53-003, Issued: January 29, 1986, Revised: February 13, 1986,

Fairchild Aircraft Corporation SA226 Series Service Bulletin No. 226-53-007, Issued: May 7, 1981, Revised: February 17, 1992,

Fairchild Aircraft SA226/SA227Structural Repair Manual (SRM) section 53-90-20, Initial Issue: March 1, 1983, Revision 24, dated August 27, 1997, and

Fairchild Aircraft Approved Repair Procedure (ARP) 53-30-9701, dated July 28, 1997.

This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Fairchild Aircraft, P.O. Box 790490, San Antonio, Texas 78279-0490, telephone (210) 824-9421. Copies may be inspected at the FAA, Central Region, Office of the Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC.

(g) This amendment (39-10403) becomes effective on April 27, 1998.

Events Leading to the Issuance of This AD
A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to Fairchild Models SA226-AT, SA226-TC, SA227-AC, and SA227-AT airplanes was published in the Federal Register on June 4, 1997 (62 FR 30483). The action proposed would require inspecting the lower belt frames at the cargo latch receptacles for cracks. If cracks are found, the proposed AD would require repairing the cracks, prior to further flight, using a repair scheme provided by the manufacturer through the Ft. Worth Airplane Certification Office. If no cracks are found, the proposed action would require reinforcing the cargo door lower belt frames by installing doublers.

Since Issuance of the Proposed AD
The proposed action required that if cracks were found, the owner/operator should contact the FAA for an approved repair scheme from Fairchild Aircraft Inc. Since the Notice of Proposed Rulemaking was published, Fairchild has developed an FAA-approved repair scheme for the cargo door belt frames. This repair scheme eliminates the need to contact the Ft. Worth Airplane Certification Office, which makes it easier for the owner to fix the airplanes with cracks without waiting for an approved repair scheme to be developed for each individual request. In addition to the availability of a repair, the FAA has clarified the instructions for the inspection of the cargo door belt frames by referencing certain fuselage stations to be inspected for cracks. Accomplishment of these actions would be in accordance with the following service information:

Fairchild Aircraft Corporation SA227 Series Service Bulletin No. 227-53-003, Issued: January 29, 1986, Revised: February 13, 1986,
Fairchild Aircraft Corporation SA226 Series Service Bulletin No. 226-53-007, Issued: May 7, 1981, Revised: February 17, 1992,
Fairchild Aircraft SA226/SA227 Structural Repair Manual (SRM), section 53-90-20, Initial Issue: March 1, 1983, Revision 24, dated August 27, 1997, or
Fairchild Aircraft Approved Repair Procedure (ARP) 53-30-9701, dated July 28, 1997.

Comments
Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the following comments.

Obtaining Repair Approval
Several commenters express concern about access to a repair scheme and the ability of the FAA to provide a repair scheme outside normal business hours (8:00 a.m. to 4:30 p.m.). The commenters went on to say that in many cases, inspections and repairs are made overnight or on the weekends and waiting on the FAA to provide a repair scheme, on a case by case basis, could cause the commercial operators flight delays and cancellations. These commenters request that the FAA approve and make available a repair scheme prior to the effective date of the proposed AD. The FAA agrees and has approved a repair scheme developed by Fairchild Aircraft Inc. The final rule will be changed to reflect the name and number of these approved repair procedures.

Change of Compliance Time
One commenter requested a change to the compliance times referenced in paragraphs (a) and (c) of the NPRM. The compliance time proposed was 500 hours time-in-service (TIS) after the effective date of this AD for the initial inspection for cracks, and if no cracks were found within the next 500 hours TIS, installing a doubler to the cargo door belt frames. The commenter wants the initial inspection compliance time extended to 900 hours TIS after the effective date of this AD, to fit into the operators' scheduled maintenance to the cargo door belt frames. The FAA does not agree. The 500 hours TIS compliance time will assure that the affected airplanes are not flying with cracks in critical structure. Failure of the cargo door during flight would cause airplane decompression and possible injury to the passengers,as well as structural damage to the airplane. The 500 hours TIS initial inspection is imposed to assure that all the affected airplanes are checked for cracks in this area within a reasonable amount of time. The installation of the doubler to strengthen the cargo door belt frames is not required for another 500 hours TIS, in order to give the owners/operator an opportunity to schedule this "down-time" into their flight schedules. If no cracks are found in the affected area, the owners/operators essentially have 1,000 hours total TIS to schedule the installation of the doublers. The final rule will not change as a result of this comment.

Crack Limits
Two comments were received regarding the discussion in the NPRM preamble. The comments addressed the section directed to the differences between the manufacturer's service bulletin and the proposed action. The commenters said that the language in the preamble implied that the manufacturer's service bulletin allowed the operators to fly with cracks. Although it was not the intent of the FAA to suggest that the manufacturer allowed flying with cracks, the FAA agrees that the language in the preamble could be interpreted this way. The FAA was trying to point out that the compliance times in the service bulletin were different from those in the proposed action, and that the service bulletin referred the operator to the manufacturer for repairs, if cracks of one inch or larger were found. The service bulletin did not require the operator to contact the manufacturer for the repair scheme prior to further flight. This language is not repeated in the final rule, and since a repair scheme is now available directly from the manufacturer, the only difference between the manufacturer's service bulletin and the action required by this AD is the difference in compliance times. The compliance times required by this AD will take precedence over the compliance times in the Fairchild service bulletins. The final rule will reflect this change to the service and repair information in the body of the AD.

The FAA's Determination
After careful review of all available information, including the service information, related to the subject presented above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed except for minor editorial corrections. The FAA has determined that these changes and corrections will not change the meaning of the AD and will not add any additional burden upon the public than was already proposed.

Cost Impact
The FAA estimates that 145 airplanes in the U.S. registry are affected by this AD, that it will take approximately 30 workhours per airplane to accomplish the initial inspection and installation of the reinforcing doubler, and that the average labor rate is approximately $60 an hour. Parts for the installation of the reinforcing doubler cost approximately $710 per airplane. Based on these figures, the totalcost impact of this AD on U.S. operators is estimated to be $363,950 or $2,510 per airplane. The FAA has no way to determine the number of affected airplanes that may have already had this action accomplished.

Regulatory Impact
The regulations adopted herein will 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 final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

For the reasons discussed above, I certify that this action (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. A copy of the final 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, Incorporation by reference, Safety.

Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by adding a new airworthiness directive (AD) to read as follows: