Federal Aviation Administration, DOT.
Final rule; request for comments.
This amendment supersedes an existing airworthiness directive (AD) for the specified Bell Helicopter Textron Canada (BHTC) model helicopters that currently requires certain checks and inspections of the tail rotor blades. If a crack is found, the existing AD requires replacing the tail rotor blade (blade) with an airworthy blade before further flight. This amendment requires the same checks and inspections as the existing AD, but expands the applicability with the addition of two BHTC Model 430 helicopter serial numbers. This amendment is prompted by the manufacturer issuing revised service information that includes the additional two serial numbers. The actions specified by this AD are intended to detect a crack in the blade, and to prevent loss of a blade and subsequent loss of control of the helicopter.
Effective March 4, 2005.
Comments for inclusion in the Rules Docket must be received on or before April 18, 2005.
Use one of the following addresses to submit comments on this AD:
• DOT Docket Web site: Go to
• Government-wide rulemaking Web site: Go to
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You may get the service information identified in this AD from Bell Helicopter Textron Canada, 12,800 Rue de l'Avenir, Mirabel, Quebec J7J1R4, telephone (450) 437–2862 or (800) 363–8023, fax (450) 433–0272. You may examine this information at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call (202) 741–6030, or go to:
You may examine the docket that contains the AD, any comments, and other information on the Internet at
Sharon Miles, Aviation Safety Engineer, FAA, Rotorcraft Directorate, Regulations and Policy Group, Fort Worth, Texas 76193–0111, telephone (817) 222–5122, fax (817) 222–5961.
On December 23, 2004, the FAA issued AD 2004–26–11, Amendment 39–13923 (70 FR 7; January 3, 2005), to require certain checks and inspections of the blades. If a crack is found, that AD requires replacing the blade with an airworthy blade before further flight. That action was prompted by three reports of cracked blades that were found during scheduled inspections. That condition, if not corrected, could result in loss of a blade and subsequent loss of control of the helicopter.
Since issuing that AD, the alert service bulletin (ASB) that is applicable to BHTC Model 430 helicopters has been revised by the manufacturer to include two additional helicopter serial numbers. Further, we discovered two typographical errors in the AD—the word “Canada” is inadvertently omitted from the manufacturer's name in the Summary section, and in Note 1 of the AD, the number for the Model 430 helicopter ASB is incorrectly stated as 430–04–32 instead of 430–04–31—as well as some minor editorial errors, which have been corrected in this AD.
Transport Canada, the airworthiness authority for Canada, notified the FAA that an unsafe condition may exist on the specified BHTC model helicopters. Transport Canada advises of the discovery of cracked blades during scheduled inspections on three occasions. Two cracks originated from the outboard feathering bearing bore underneath the flanged sleeves. The third crack started from the inboard feathering bearing bore. Investigation found that the cracks originated from either a machining burr or a corrosion site in the bearing bore underneath the flanged sleeves.
BHTC has issued ASB No. 222–04–100 for Model 222 and 222B helicopters; ASB No. 222U–04–71 for Model 222U helicopters; and ASB No. 230–04–31 for Model 230 helicopters, all dated August 27, 2004; and, ASB No. 430–04–31, Revision A, dated November 29, 2004, for Model 430 helicopters. The ASBs specify a visual inspection of the blade root end around the feather bearings for a crack, not later than at the next scheduled inspection, and thereafter at intervals not to exceed 3 flight hours. Further, they describe a visual inspection for a crack, to include removing the blade from the helicopter, within 50 flight hours, and thereafter at intervals not to exceed 50 flight hours. Transport Canada classified these ASBs as mandatory and issued AD CF–2004–21R1, dated December 9, 2004, to ensure the continued airworthiness of these helicopters in Canada. This AD differs from those ASBs in that it requires an initial visual check, which may be
These helicopter models are manufactured in Canada and are type certificated for operation in the United States under the provisions of 14 CFR 21.29 and the applicable bilateral agreement. Pursuant to the applicable bilateral agreement, Transport Canada has kept the FAA informed of the situation described above. The FAA has examined the findings of Transport Canada, reviewed all available information, and determined that AD action is necessary for products of these type designs that are certificated for operation in the United States.
This previously described unsafe condition is likely to exist or develop on other helicopters of the same type design. Therefore, this AD supersedes AD 2004–26–11 to require the following:
• Within 3 hours TIS, and thereafter at intervals not to exceed 3 hours TIS, clean and visually check both sides of each blade for a crack in the area around the tail rotor feathering bearing. An owner/operator (pilot) may perform this check. Pilots may perform the checks required by paragraph (a) of this AD because they require no tools, can be done by observation, and can be done equally well by a pilot or a mechanic. However, the pilot must enter compliance with these requirements into the helicopter maintenance records by following 14 CFR 43.11 and 91.417(a)(2)(v).
• Within 50 hours TIS, and thereafter at intervals not to exceed 50 hours TIS, clean and inspect both sides of each blade for a crack using a 10X or higher magnifying glass.
• If a crack is found in the blade paint during a visual check or inspection, further inspect the blade as follows, before further flight:
• Remove the blade. Remove the paint to the bare metal in the area of the suspected crack by using plastic metal blasting (PMB) or a nylon web abrasive pad and abrading the blade surface in a span-wise direction only.
• Using a 10X or higher power magnifying glass, inspect the blade for a crack.
• If a crack is found, replace the blade with an airworthy blade before further flight.
• If no crack is found in the blade surface, refinish the blade by applying one coat of epoxy polyamide primer, MIL–P–23377 or MIL–P–85582, so that the primer overlaps the existing coats just beyond the abraded area. Let the area dry for 30 minutes to 1 hour. Then, apply one sealer coat of polyurethane, MILC85285 TYI CL2, color number 27925 (semi-gloss white), per Fed. Std. 595, and reinstall the blade.
This AD is an interim action, pending release of additional service information from the manufacturer concerning instructions for inspecting and reworking the affected blades. We expect that service information to eliminate the recurring inspections required by this AD.
The short compliance time involved is required because the previously described critical unsafe condition can adversely affect the controllability and structural integrity of the helicopter. Therefore, checking the blade for a crack within 3 hours TIS, and thereafter at intervals not to exceed 3 hours TIS, is required, and this AD must be issued immediately.
Since a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days.
We estimate that this AD will affect 156 helicopters and will require:
• 0.25 work hour for a pilot check, and 2 work hours for a maintenance inspection, at an average labor rate of $65 per work hour; and
• Parts, which will cost an estimated $13,410 per helicopter.
Based on these figures, the estimated total cost impact of the AD on U.S. operators is $2,842,320 per year, assuming each helicopter will require 200 pilot checks, 12 maintenance inspections, and one blade replacement per year.
This AD is a final rule that involves requirements that affect flight safety and was not preceded by notice and an opportunity for public comment; however, we invite you to submit any written data, views, or arguments regarding this AD. Send or deliver your comments to an address listed under
We will post all comments we receive, without change, to
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 the regulation:
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 an economic evaluation of the estimated costs to comply with this AD. See the DMS to examine the economic evaluation.
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.
Air transportation, Aircraft, Aviation safety, Safety.
49 U.S.C. 106(g), 40113, 44701.
To detect a crack in the blade and to prevent loss of the blade and subsequent loss of control of the helicopter, accomplish the following:
(a) Within 3 hours time-in-service (TIS), and thereafter at intervals not to exceed 3 hours TIS, clean and visually check both sides of each blade for a crack in the paint in the areas shown in Figure 1 of this AD. An owner/operator (pilot), holding at least a private pilot certificate, may perform this visual check and must enter compliance with this paragraph into the helicopter maintenance records by following 14 CFR 43.11 and 91.417(a)(2)(v).
Bell Helicopter Textron Alert Service Bulletin (ASB) No. 222–04–100, No. 222U–04–71, and No. 230–04–31, all dated August 27, 2004, and ASB No. 430–04–31, Revision A, dated November 29, 2004, pertain to the subject of this AD.
(b) If the visual check required by paragraph (a) reveals a crack in the paint, before further flight, remove the blade and follow the requirements in paragraphs (c)(2) through (c)(3)(ii) of this AD.
(c) Within the next 50 hours TIS, unless accomplished previously, and thereafter at intervals not to exceed 50 hours TIS, clean the blade by wiping down both surfaces of each blade in the inspection area depicted in Figure 1 of this AD using aliphatic naphtha (C–305) or detergent (C–318) or an equivalent. Using a 10X or higher power magnifying glass, visually inspect both sides of the blade in the areas depicted in Figure 1 of this AD.
(1) If a crack is found, even if only in the paint, before further flight, remove the blade from the helicopter and proceed with the following:
(2) Remove the paint on the blade down to the bare metal in the area of the suspected crack by using plastic metal blasting (PMB) or a nylon web abrasive pad. Abrade the blade surface in a span-wise direction only.
PMB may cause damage to helicopter parts if untrained personnel perform the paint removal. BHT–ALL–SPM, chapter 3, paragraph 3–24, pertains to the subject of this AD.
(3) Using a 10X or higher power magnifying glass, inspect the blade for a crack.
(i) If a crack is found, replace the blade with an airworthy blade before further flight.
(ii) If no crack is found in the blade surface, refinish the blade by applying one coat of epoxy polyamide primer, MIL–P–23377 or MIL–P–85582, so that the primer overlaps the existing coats just beyond the abraded area. Let the area dry for 30 minutes to 1 hour. Then, apply one sealer coat of polyurethane, MILC85285 TYI CL2, color number 27925 (semi-gloss white), per Fed. Std. 595. Reinstall the blade.
BHT–ALL–SPM, chapter 4, pertains to painting the blade.
(d) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Contact the Safety Management Group, FAA, for information about previously approved alternative methods of compliance.
(e) Special flight permits may be issued by following 14 CFR 21.197 and 21.199 to operate the helicopter to a location where the requirements of this AD can be accomplished provided you do not find a crack in the blade paint during a check or inspection.
(f) This amendment becomes effective March 4, 2005.
The subject of this AD is addressed in Transport Canada (Canada) Airworthiness Directive CF–2004–21R1, dated December 9, 2004.