2001-04-14: Fuselage Frame

2001-04-14 EUROCOPTER FRANCE: Amendment 39-12133. Docket No. 2000-SW-17-AD. Supersedes AD 85-14-06, Amendment 39-5089, and 85-14-06 R1, Amendment 39-5121, Docket No. 85-ASW-15. Applicability: Model AS350B, AS350B1, AS350B2, AS350B3, AS350BA, AS350C, AS350D, AS350D1, AS355E, AS355F, AS355F1, AS355F2, and AS355N helicopters, 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 (e) 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; andif the unsafe condition has not been eliminated, the request should include specific proposed actions to address it. Compliance: Required as indicated, unless accomplished previously. To eliminate confusion and unnecessary costs and to prevent a cracked fuselage frame (frame), tailboom failure, and subsequent loss of control of the helicopter, accomplish the following: (a) Inspect the fuselage-to-tailboom attachment bolts in accordance with paragraph (d) within 30 hours time-in-service (TIS). (b) Inspect the fuselage-to-tailboom attachment bolts in accordance with paragraph (d) within 30 hours TIS of replacing or reinstalling a tailboom. (c) Repeat the inspection in accordance with paragraph (d) at intervals not to exceed 2500 hours or 6 years TIS, whichever occurs first. (d) Inspect the fuselage-to-tailboom attachment bolts for proper torque range and the frame, part number 350A21-1247-00, for a crack at the fuselage-to-tailboom interface. (1)Procedure for inspecting proper torque range: (i) Using a fine-point felt tip pen, mark the position of the nut relative to the assembly. (ii) One at a time, slightly loosen each nut. Do not allow the corresponding bolt to rotate relative to the assembly. (iii) Tighten the nut with a properly calibrated torque wrench until the mark on the nut lines up with the mark on the assembly. (iv) Record the torque value required to line up the two marks. (2) Interpretation of the recorded torque values for each nut: (i) If the torque value is less than 0.3 mdaN (26 in-lbs) on any nut: (A) Remove the tailboom. (B) Perform a dye-penetrant inspection for a crack in the bending radius of the frame. (C) If a crack is found, repair or replace the frame with an airworthy frame before further flight. (ii) If the torque value is between 0.3 mdaN and 1 mdaN (26 to 88 in-lbs), re-torque to 0.75 mdaN to 0.9 mdaN (67 to 79 in-lbs). (iii) If the torque value is equal to or greater than 1 mdaN (88 in-lbs), remove the nut and bolt and replace them with a new nut and bolt. Torque the nut to 0.75 mdaN to 0.9 mdaN (67-79 in-lbs). Note 2: Aerospatiale Service Bulletins AS 355 No. 05.14 and AS 350 No. 05.16 pertain to the subject of this AD. (e) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Regulations Group, Rotorcraft Directorate, FAA. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Regulations Group. Note 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Regulations Group. (f) Special flight permits may be issued in accordance with 14 CFR 21.197 and 21.199 to operate the helicopter to a location where the requirements of this AD can be accomplished. (g) This amendment becomes effective on April 10, 2001.