Discussion
What Events Have Caused This AD?
The FAA received several reports of dragging brakes on Fairchild SA226 series airplanes when the brake pedals were operated during taxi operations. After troubleshooting by maintenance personnel, the problem was traced to the brake master cylinder. Disassembly of the malfunctioning master cylinders revealed broken check valve spring washers that, together with the action of the shuttle valve, prevented the release of brake pressure. Based on observed failures, FAA has determined that the brake master cylinders should be replaced at intervals of 15,000 hours time-in-service.
What Is the Potential Impact if FAA Took No Action?
This condition, if not detected or corrected, could cause dragging brakes, which can result in overheated brakes and cause an in-flight wheelwell fire if the dragging takes place during takeoff and the gear is later retracted.
Has FAA Taken Any Action to This Point?We issued 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 SA226 and SA227 series airplanes equipped with Skidmore-Wilheim Model V1-15-1000 brake master cylinders. This proposal was published in the Federal Register as a supplemental notice of proposed rulemaking (NPRM) on December 20, 2001 (66 FR 65663). The supplemental NPRM proposed to required you replace these brake master cylinders with new or overhauled units of the same design.
Was the Public Invited To Comment?
The FAA encouraged interested persons to participate in the making of this amendment. We did not receive any comments on the supplemental proposed rule or on our determination of the cost to the public.
FAA's Determination
What Is FAA's Final Determination on This Issue?
After careful review of all available information related to the subject presented above, we have determined that air safety and the public interest require the adoption of the rule as proposed except for minor editorial corrections. We have determined that these minor corrections:
--provide the intent that was proposed in the supplemental NPRM for correcting the unsafe condition; and
--do not add any additional burden upon the public than was already proposed in the supplemental NPRM.
Cost Impact
How Many Airplanes Does This AD Impact?
We estimate that this AD affects 140 airplanes in the U.S. registry.
What Is the Cost Impact of This AD on Owners/Operators of the Affected Airplanes?
We estimate the following costs to accomplish the replacements:
Labor cost
New or overhauled parts cost (4 parts for each aircraft required)
Total cost per airplane
Total cost on U.S. operators
8 workhours x $60 per hour = $480
4 parts x $200 = $800
$1,280
140 x $1,280 = $179,200.
Regulatory Impact
Does This AD Impact Various Entities?
The regulations adopted herein 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. Therefore, it is determined that this final rule does not have federalism implications under Executive Order 13132.
Does This AD Involve a Significant Rule or Regulatory Action?
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, under 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.
Sec. 39.13 [Amended]
2. FAA amends Sec. 39.13 by adding a new AD to read as follows: