Airworthiness Directive · Amendment 39-11738 · Bell Helicopter Textron Canada (BHTC) Model 222, 222B, 222U, and 230 Helicopters
Bell Helicopter Textron Canada (BHTC) Model 222, 222B, 222U, and 230 Helicopters
Model 222 helicopters, serial number (S/N) 47006 through 47089; Model 222B helicopters, S/N 47131 through 47156; Model 222U helicopters, S/N 47501 through 47574; and Model 230 helicopters, S/N 23001 through 23038 inclusive, certificated in any category.
Note 1: This AD applies to each helicopter identified in the preceding applicability provision, regardless of whether it has been otherwise modified, altered, or repaired in the area subject to the requirements of this AD. For helicopters that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (b) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment adopts a new airworthiness directive (AD) for BHTC Model 222, 222B, 222U, and 230 helicopters that requires inspecting each flapping bearing to yoke attachment bolt (bolt) and replacing each bolt that shows thread damage, shank wear, or corrosion pitting with an airworthy bolt. This amendment is prompted by the discovery of a fractured bolt during a post-flight inspection. The actions specified by this AD are intended to prevent a fracture of a bolt, failure of the bearing and yoke interface, and subsequent loss of control of the helicopter.
To prevent the fracture of a flapping bearing to yoke attachment bolt (bolt), failure of the bearing and yoke interface, and subsequent loss of control of the helicopter, accomplish the following:
(a) Remove one bolt at a time and inspect each bolt located as shown in Figure 1.
Note 2: For main rotor hubs installed on rotorcraft, the bolts may be removed, inspected, and installed one at a time.
Note 3: Bell Helicopter Textron Canada Alert Service Bulletins 230-98-15, 222-98-83, and 222U-98-54, all dated October 12, 1998, pertain to the subject of this AD.
(i) Clean each bolt with a cloth dampened with methyl ethyl ketone, RHO SOLV756, Desoto 110, or equivalent.
(ii) Visually inspect each bolt and discard those that have thread damage, shank wear, or corrosion.
(iii) Apply corrosion preventative compound MIL-C-16173 GR2, or equivalent, to the shank of the bolt only.
(iv) Install, torque, and lockwire each bolt.
(v) Coat each bolt head and nut with corrosion preventative compound MIL-C-16173 GR1 or equivalent.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
