AD 95-17-09 R1

This amendment revises Airworthiness Directive (AD) 95-17-09, which requires relocating the left-hand (LH) and right-hand (RH) essential bus current limiters (225 amp) to the battery bus (main bus tie) on certain Fairchild Aircraft SA226 and SA227 series airplanes. The Federal Aviation Administration (FAA) has determined that the applicability of the current AD should be changed to reflect a different serial number range and model designation of certain SA227 series airplanes. This action retains the essential bus current limiter relocations required by AD 95-17-09, and revises the Applicability section of that AD. The actions specified by this AD are intended to prevent failure of the LH and RH essential bus when engine failure results in a blown generator current limiter, which could result in loss of airplane electrical power.

Final rule

95-17-09 R1 FAIRCHILD AIRCRAFT: Amendment 39-9550; Docket No. 95-CE-13-AD. Revises AD 95-17-09, Amendment 39-9339.

Applicability: The following model and serial number airplanes, certificated in any category, that utilize a direct current (DC) generator:

Models
Serial Numbers
SA226-T, SA226-AT, SA226-TC,
and SA226-T(B)
All
SA227-AC, SA227-AT, SA227-BC,
and SA227-TT
420 through 783, and
785 through 789
SA227-CC and SA227-DC
784, and 790 through 883

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 (c) 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 within the next 2,000 hours time-in-service after the effective date of this AD, unless already accomplished (compliance with AD 95-17-09).

To prevent failure of the left hand (LH) and right hand (RH) essential bus when engine failure results in a blown generator current limiter, which could result in loss of airplane electrical power, accomplish the following:

(a) Relocate the LH and RH essential bus current limiters (225 amp) to the battery bus (main bus tie) in accordance with Fairchild Aircraft Engineering Kit Drawing 27K82376, "Current Limiter Rebusing Kit," as referenced in the following service bulletins (SB):

SB
Date
Models Affected
226-24-034
September 29, 1994
All affected SA226 models
227-24-015
September 29, 1994
SA227-AC, SA227-AT,
SA227-BC, and SA227-TT
CC7-24-002
September 29, 1994
SA227-CC and SA227-DC

(b) 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.

(c) An alternative method of compliance or adjustment of the compliance time that provides an equivalent level of safety may be approved by the Manager, Fort Worth Airplane Certification Office (ACO), FAA, 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 ACO.

(d) Alternative methods of compliance approved for AD 95-17-09 are approved as alternative methods of compliance for this AD.

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

(e) The modification required by this AD shall be done in accordance with Fairchild Aircraft Engineering Kit Drawing 27K82376, "Current Limiter Rebusing Kit," as referenced in Fairchild Aircraft Service Bulletins 226-24-034, 227-24-015, and CC7-24-002, all Issued: September 29, 1994. This incorporation by reference was previously 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. Copies may be inspected at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW., 7th Floor, suite 700, Washington, DC.

(f) This amendment (39-9950) revises AD 95-17-09, Amendment 39-9339.

(g) This amendment becomes effective on May 13, 1996.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to certain Fairchild Aircraft SA226 and SA227 series airplanes that utilize a DC generator was published in the Federal Register on October 13, 1995 (60 FR 53309). The action proposed to revise AD 95-17-09 by retaining the requirement of relocating the LH and RH essential bus current limiters (225 amp) to the battery bus (main bus tie); and revising the Applicability section to reflect correct serial numbers and incorporating the correct airplane model designation in paragraph (a) of AD 95-17-09. Accomplishment of the proposed modification would be in accordance with Fairchild Aircraft Engineering Kit Drawing 27K82376, "Current Limiter Rebusing Kit," as referenced in Fairchild Service Bulletin (SB) 226-24-034, SB 227-24-015, and SB CC7-24-002, all Issued: September 29, 1994.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments have been received regarding the proposal or the FAA's estimate of the cost impact upon the public.

After careful review of all available 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 minor corrections will not change the meaning of the AD and will not add any additional burden upon the public than was already proposed.

The FAA estimates that 622 airplanes in the U.S. registry will be affected by this AD, that it will take approximately 4 workhours per airplane to accomplish the required action, and that the average labor rate is approximately $60 an hour. Parts cost approximately $98 per airplane. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $210,236 or $338 per airplane. This figure is based on the assumption that no affected airplane owner/operator has incorporated the required modification. Fairchild Aircraft has informed the FAA that parts have not been distributed to any owner/operator of the affected airplanes.

The required action only corrects a model designation and certain serial numbers of certain SA227 series airplanes that are affected by AD 95-17-09. The cost impact upon the public specified in this AD is exactly the same as that currently required by AD 95-17-09.

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 USC 106(g), 40113, 44701.

Section 39.13 - [AMENDED]
2. Section 39.13 is amended by removing Airworthiness Directive (AD) 95-17-09, Amendment 39-9339 (60 FR 43361, August 21, 1995), and by adding a new AD to read as follows: