Discussion
On May 1, 2006, 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 CDC Models SR20 and SR22 airplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on May 8, 2006 (71 FR 26707). The NPRM proposed to
require you to check the maintenance records to determine whether the brake caliper piston O-ring seals were replaced at the last annual or 100-hour inspection. If the O-rings were not replaced, this proposed AD would require you to replace the O-ring seals with new seals or replace brake calipers. This proposed AD would also require you to modify the
main landing gear wheel fairings to add temperature indicator sticker inspection holes, trim the wheel fairings to prevent them from holding fluids, install temperature indicator stickers on the brake calipers, and insert Revision A6 (with revised preflight walk-around and taxi procedures) into the Pilot's Operating Handbook (POH).
Comments
We provided the public the opportunity to participate in developing this AD. The following presents the comment received on the proposal and FAA's response to the comment:
Comment Issue: Increase Emphasis on the Operational Aspects of Overheating of the Brakes
CDC points out that the brakes, as delivered, meet certification requirements, and when properly used, will provide the expected performance and service. We conclude that CDC believes that the AD overemphasizes the required maintenance actions and hardware upgrades, without explaining the operational details that will prevent brake
caliper O-ring damage.
Our intent is that the AD stress continued operational safety by removing and replacing potentially damaged O-rings or replacement of existing brake calipers with new heavier duty calipers (with new O-rings installed), adding brake caliper temperature stickers with a newinspection hole in the wheel fairings (to detect potential O-ring damage before brake fluid leaks develop), and adding a revision to the Pilot's Operating Handbook (to emphasize brake preflight inspections, checking the color of the brake caliper temperature sticker for evidence of brake caliper overheating, and limiting the engine RPM during taxi to 1000 RPM).
We agree that the operational change to limit engine RPM during taxi (found in Revision A6 to the POH) is the most important consideration toward preventing brake caliper O-ring seal damage. This AD is requiring this action so we are not changing the AD as a result of this comment.
Conclusion
We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed except for minor editorial corrections. We have determined that these minor corrections:
Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and
Do not add any additional burden upon the public than was already proposed in the NPRM.
Costs of Compliance
We estimate that this AD affects 2,135 airplanes in the U.S. registry.
We estimate the following costs to do the check of maintenance records to determine whether the brake caliper piston O-ring seals were replaced at the last annual or 100-hour inspection:
Labor cost
Parts cost
Total cost per airplane
Total cost on U.S. operators
1 work-hour x $80 = $80
Not Applicable
$80
$170,800
We estimate the following costs to install any necessary O-ring seals that would be required based on the results of this check of maintenance records. We have no way of determining the number of airplanes that may need this seal installation:
Labor cost
Parts cost
Total cost per airplane
4 work-hours x $80 = $320
$8
$328
We estimate the following costs to replace any brake calipers on Model SR20 airplanes, serial numbers (S/Ns)1005 through 1194, that would be required based on the results of this check of maintenance records. We have no way of determining the number of these Model SR20 airplanes that may need to replace brake calipers:
Labor cost
Parts cost
Total cost per airplane
12 work-hours x $80 = $960
$1,167
$2,127
We estimate the following costs to replace any brake calipers on Model SR20 airplanes, S/Ns 1195 through 1600, that would be required based on the results of this check of maintenance records. We have no way of determining the number of these Model SR20 airplanes that may need to replace brake calipers:
Labor cost
Parts cost
Total cost per airplane
8 work-hours x $80 = $640
$1,167
$1,807
We estimate the following costs to replace any brake calipers on Model SR22 airplanes that would be required based on the results of this check of maintenance records. We have no way of determining the number of Model SR22 airplanes that may need to replace brake calipers:Labor cost
Parts cost
Total cost per airplane
5 work-hours x $80 = $400
$845
$1,245
We estimate the following costs to do the modification of the MLG wheel fairings to add the temperature indicator sticker inspection holes, trim the wheel fairings to prevent them from holding fluids, and install the temperature indicator sticker on the brake calipers:
Labor cost
Parts cost
Total cost per airplane
Total cost on U.S. operators
2 work-hours x $80 = $160
$2
$162
$345,870
The CDC has indicated that CDC will provide warranty credit as stated in the service information for modifying the MLG wheel fairings by adding the temperature indicator sticker inspection holes, trimming the wheel fairings to prevent them from holding fluids, and installing the temperature indicator sticker on the brake calipers.
We estimate the following costs to do the insertion of Revision A6 into the POH:
Labor cost
Parts cost
Total cost per airplane
Total cost on U.S. operators
1 work-hour x $80
Not Applicable
$80
$170,800
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106 describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the agency's authority.
We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, "General requirements." Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this AD.
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 the 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 other information as included in the Regulatory Evaluation) 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 "Docket No. FAA-2006-24010; Directorate Identifier 2006-CE-14-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 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: