AD 2013-13-06 Airworthiness Directives; Various Restricted Category Helicopters

This AD becomes effective September 10, 2013.

(1) The Manager, Rotorcraft Certification Office, FAA, may approve AMOCs for this AD. Send your proposal to: Michael Kohner, Aviation Safety Engineer, Rotorcraft Certification Office, Rotorcraft Directorate, FAA, 2601 Meacham Blvd., Fort Worth, Texas 76137; telephone (817) 222-5170; email 7-avs-asw-170@faa.gov. (2) For operations conducted under a 14 CFR part 119 operating certificate or under 14 CFR part 91, subpart K, we suggest that you notify your principal inspector, or lacking a principal inspector, the manager of the local flight standards district office or certificate holding district office before operating any aircraft complying with this AD through an AMOC.

BHTI Alert Service Bulletin (ASB) 212-94-92, Revision A, dated March 13, 1995; BHTI Operations Safety Notice (OSN) 204-85-6, OSN 205-85-9, and OSN 212-85-13, all dated November 14, 1985 and co-published as one document; BHTI ASB 205B-02-39, Revision B, dated November 22, 2002; and BHTI ASB 212-02-116, Revision A, dated October 30, 2002, which are not incorporated by reference, contain additional information about the subject of this AD.

(1) Within 10 hours time-in-service (TIS), create a component history card or equivalent record and determine and record the total hours TIS for each grip. If the total hours TIS cannot be determined from the helicopter records, assume and record 50 hours TIS for each month for which the hours cannot be determined with the grip installed on any helicopter. Continue to count and record the hours TIS and begin to count and record the number of times the helicopter engine(s) are started (engine start/stop cycles). (2) Within 10 hours TIS, and then at intervals not to exceed 25 hours TIS, without removing the main rotor blades: (i) Clean the exposed surfaces of the upper and lower tangs of each grip with denatured alcohol and wipe dry. (ii) Using a 10X or higher magnifying glass, visually inspect the exposed surfaces of the upper and lower tangs of each grip for a crack. Pay particular attention to the lower surface of each lower grip tang from the main rotor blade bolt-bushing flange to the leading and trailing edge of each grip tang as depicted in Figure 5-7, Inspection of Main Rotor Hub Grip (1200 Hours), Revision 9, dated August 8, 2008, of Chapter 5, Inspections and Component Overhaul Schedule, Revision 11, dated April 30, 2010, of Bell Helicopter Textron, Inc. (BHTI), BHT-212-MM-1, Revision 13, dated September 16, 2010. (iii) At the intervals shown in Table 1 to Paragraph (e) of this AD, ultrasonic (UT) inspect each grip for a crack in accordance with the BHTI Nondestructive Inspection Procedure, Log No. 00-340, Revision E, dated April 9, 2002. The UT inspection of the grip must be performed by a Nondestructive Testing (NDT) UT Level I Special, Level II, or Level III inspector who is qualified under the guidelines established by MIL-STD-410E, ATA Specification 105, AIA-NAS-410, or an FAA-accepted equivalent for qualification standards of NDT Inspection/Evaluation Personnel. Table 1 to Paragraph ( e ) UT inspect grip, P/N Within 30 days, for a grip with the following or more hours TIS: Thereafter, at intervals not to exceed the following number of hours TIS or the engine start/stop cycles, whichever occurs first: Hours TIS Engine start/stop cycles 204-011-121-009 or ASI-4011-121-9 4,000 400 1,600 204-011-121-121 500 150 600 204-011-121-005 or -113, if the grip was EVER installed on a Model 205B or Model UH-1N helicopter 4,000 400 1,600 204-011-121-117, if the grip was EVER installed on a Model 205B helicopter 500 150 600 (3) At intervals not to exceed 1,200 hours TIS or 24 months, whichever occurs first: (i) Remove each main rotor blade, and (ii) Inspect each grip buffer pad on the inner surfaces of each grip tang for delamination as depicted in Figure 5-7, Inspection of Main Rotor Hub Grip (1200 Hours), Revision 9, dated August 8, 2008, of Chapter 5, Inspections and Component Overhaul Schedule, Revision 11, dated April 30, 2010, of Bell Helicopter Textron, Inc., BHT-212-MM-1, Revision 13, dated September 16, 2010. If there is any delamination, remove the buffer pad and inspect the grip surface for corrosion or other damage. (4) Within 2,400 hours TIS or at the next overhaul of the main rotor hub, whichever occurs first, and then at intervals not to exceed 2,400 hours TIS: (i) Remove each main rotor blade. (ii) Remove each grip buffer pad (if installed) from the inner surfaces of each grip tang. (iii) Visually inspect the grip surfaces for corrosion or other damage. (iv) Fluorescent-penetrant inspect (FPI) the grip for a crack, paying particular attention to the upper and lower grip tangs. When inspecting a grip, P/N 204-011-121-005, 204-011-121-009, or 204-011-121-113, or ASI-4011-121-9, pay particular attention to the leading and trailing edges of the grip barrel. (5) Before further flight: (i) Replace any cracked grip with an airworthy grip. (ii) Replace any grip with any corrosion or other damage with an airworthy grip, or repair the grip if the corrosion or other damage is within the maximum repair limitations. (iii) Rem

This AD defines the unsafe condition as a crack in the lower main rotor blade bolt lug. This condition could result in failure of a grip, separation of a main rotor blade, and subsequent loss of control of the helicopter.