Comments Invited
This AD is a final rule that involves requirements affecting flight safety, and we did not provide you with notice and an opportunity to provide your comments prior to it becoming effective. However, we invite you to participate in this rulemaking by submitting written comments, data, or views. We also invite comments relating to the economic, environmental, energy, or federalism impacts that resulted from adopting this AD. The most helpful comments reference a specific portion of the AD, explain the reason for any recommended change, and include supporting data. To ensure the docket does not contain duplicate comments, commenters should send only one copy of written comments, or if comments are filed electronically, commenters should submit them only one time.
We will file in the docket all comments that we receive, as well as a report summarizing each substantive public contact with FAA personnel concerning this rulemaking during the comment period. We will consider all the comments we receive and may conduct additional rulemaking based on those comments.
Discussion
On March 29, 2011, the FAA issued AD 2011-08-01, Amendment 39-16651 (76 FR 18865, April 6, 2011), which superseded previously existing emergency AD 2010-25-51, for Bell Model 212 helicopters with a fitting, part number (P/N) 212-010-103-007 and with a certain serial number (S/ N). AD 2011-08-01 retained the requirements of AD 2010-25-51 to replace certain serial-numbered fittings and perform an MPI for a crack on other serial-numbered fittings, and expanded the applicability to require performing an MPI on additional serial-numbered fittings. The AD based the compliance time for performing an MPI on the number of hours time-in-service (TIS) of the fitting. That AD was prompted by reports of cracks in fittings. Subsequently, the cracking was determined to have been caused by the manufacturer's failure to follow approved manufacturing processes and controls during the quenching operation from the heat treating of the fittings.
Since AD 2011-08-01 was issued, two additional fittings were found with a crack. Based on these additional reported cracks, we have determined that a crack may occur in a fitting regardless of the hours TIS. In addition, fitting P/Ns 204-012-102-001, -005, -009, 212-010- 103-005, and -101, which are used on other model helicopters, are susceptible to the same type of cracking because they are of similar design and manufacture to fitting P/N 212-010-103-007, which was the subject of AD 2011-08-01. Failure of a fitting in flight may result in the loss of a main rotor blade and subsequent loss of helicopter control. Therefore, this AD reduces the compliance time for performing an MPI of some serial-numbered fittings by requiring an MPI for all applicable serial-numbered fittings within 25 hours TIS or 15 days, whichever occurs first. This AD does not require you to report a cracked fitting to the Rotorcraft Certification Office.
FAA's Determination
We are issuing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.
Related Service Information
We have reviewed Bell Alert Service Bulletin (ASB) No. 212-10-141, Revision A, dated November 18, 2010, for the Model 212 helicopter, which specifies the immediate removal from service of fittings with certain S/Ns.
We have also reviewed ASB No. 204-11-66 for the Model 204B helicopters; ASB No. 205-11-107 for the Model 205A and 205A-1 helicopters; ASB No. 205B-11-58 for the Model 205B helicopters; ASB No. 210-11-08 for the Model 210 helicopters; and ASB No. 212-10-142, Revision B for the Model 212 helicopters; all dated May 31, 2011. These ASBs specify:
For certain serial-numbered fittings with less than 400 flight hours, performing an initial MPI within 100 flight hours but before the fitting reaches 425 flight hours or before November 26, 2011, whichever occurs first.
For certain serial-numbered fittings with more than 400 hours, performing an initial MPI within 25 flight hours or before November 26, 2011, whichever occurs first.
Certain serial-numbered fittings that have already had an MPI during main rotor hub assembly maintenance or during an overhaul do not need an additional MPI. Historical records must be annotated to show compliance during records inspection.
If defects are found, returning the removed strap fittings to Bell.
If no defects are found, re-identifying the fitting by adding an ``FM'' at the end of the part number and making a record entry.
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Performing a recurring MPI on all fittings, regardless of S/N and prefix, at 1,200 hours or 24 months for all models, except the Model 210, and at the tension-torsion (TT) strap replacement for the Model 210 helicopters.
AD Requirements
This AD supersedes AD 2011-08-01 (76 FR 18865, April 6, 2011) and requires for any Model 204B, 205A, 205A-1, 205B, 210 and 212 helicopter with certain fittings the following actions:
Within 25 hours TIS or 15 days, whichever occurs first, performing an MPI of each fitting for a crack.
If a fitting is cracked, before further flight, replacing it with an airworthy fitting.
If a fitting is not cracked, re-identifying the fitting and its component history card or equivalent record by adding ``FM'' at the end of the P/N.
If an MPI has previously been performed on a fitting and the component history card or equivalent record of the fitting has been re- identified with ``FM'' at the end of the P/N, the requirements of this AD have been met.
Differences Between This AD and the Service Information
This AD differs from the ASBs because we require an MPI within 25 hours time-in-service or 15 days, whichever occurs first, of any fitting with an affected P/N and S/N. Bell requires differentcompliance times depending on the hours TIS of the fitting. We do not require the immediate removal of fittings, P/N 212-010-103-007, with certain S/Ns because the MPI provides the necessary level of safety. We do not require returning parts to Bell.
Costs of Compliance
We estimate that this AD affects 152 helicopters of U.S. registry and that labor costs average $85 per work-hour. Based on these estimates, we expect the following costs to comply with this AD:
We estimate that 304 fittings (2 per helicopter) will need to be MPI inspected for a crack and that this task will require 40 work-hours. No parts are needed for the inspection, bringing the total cost per helicopter to $3,400; $516,800 for all U.S. operators.
If a fitting is cracked, replacement parts will cost $2,367 per fitting. Labor costs will not be an additional expense as they can be absorbed as part of the inspection.
According to Bell's service information, some of the costs of this AD may be coveredunder warranty, thereby reducing the cost impact on affected individuals. We do not control warranty coverage by Bell. Accordingly, we have included all costs in our cost estimate.
FAA's Justification and Determination of the Effective Date
Providing an opportunity for public comments prior to adopting these AD requirements, would delay implementing the safety actions needed to correct this known unsafe condition. Therefore, we find that the risk to the flying public justifies waiving notice and comment prior to the adoption of this rule because the required corrective actions must be accomplished within 15 days, a very short time period based on the average flight-hour utilization rate of these helicopters.
Since an unsafe condition exists that requires the immediate adoption of this AD, we determined that notice and opportunity for public comment before issuing this AD are impracticable and that good cause exists for making this amendment effective in less than 30 days.
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 rulemaking action.
Regulatory Findings
We 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, I certify that this AD:
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);
3. Will not affect intrastate aviation in Alaska to the extent that it justifies making a regulatory distinction; and
4. 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 an economic evaluation of the estimated costs to comply with this AD and placed it in the AD docket.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by Reference, Safety.