AD 2021-09-05 Airworthiness Directives; Airbus Helicopters

This AD replaces AD 2016-08-20, Amendment 39-18497 (81 FR 26103, May 2, 2016).

(1) For helicopters without modification (MOD) 074775, or MOD AH 350A087421 or SB EC130-53-029 installed, at the compliance time specified by the hours time-in-service (TIS) accumulated on the junction frame in Figure 1 to this paragraph, do the following: ER28AP21.009 (i) Remove the horizontal stabilizer; using a clean, lint-free, white cloth soaked with liquid Methyl Ethyl Ketone (MEK), clean the inside of the junction frame (a) as shown in Figure 1 of Airbus Helicopters Emergency Alert Service Bulletin No. 05A017, Revision 7, dated March 21, 2018 (EASB 05A017, Rev 7); and visually inspect for cracking around the circumference of the junction frame, in the web of the junction frame (a) and in the radius between the web and the flange of the tail boom side as shown in Figure 1 EASB 05A017, Rev 7. Pay particular attention to the area around the 4 spars (b) as shown in Figure 1 of EASB 05A017, Rev 7. Examples of cracks are shown in Figure 3 of EASB 05A017, Rev 7. If there is a crack, before further flight, replace or repair the junction frame in accordance with an FAA approved repair procedure. Repairing or replacing the junction frame does not constitute terminating action for the requirements of this AD. (ii) Thereafter following paragraph (f)(1)(i) of this AD, within 25 hours TIS or 390 sling cycles for helicopters that perform external load carrying operations, whichever occurs first, and thereafter at intervals not exceeding 25 hours TIS or 390 sling cycles, whichever occurs first, either perform the actions of paragraph (f)(1)(i) of this AD or, if the surface of the junction frame area is clean, use a borescope through the horizontal stabilizer opening to borescope inspect for a crack around the circumference of the junction frame, and in the web of the junction frame (a) and in the radius between the web and the flange on the tail boom side as shown in Figure 2 EASB 05A017, Rev 7. Pay particular attention to the area around the 4 spars (b) of Figure 2 of EASB 05A017, Rev 7. Examples of cracks are shown in Figure 3 of EASB 05A017, Rev 7. For purposes of this AD, a sling cycle is defined as one landing with or without stopping the rotor or one external load-carrying operation; an external load-carrying operation occurs each time a helicopter picks up an external load and drops it off. If there is a crack, before further flight, replace or repair the junction frame in accordance with an FAA approved repair procedure. Repairing or replacing the junction frame does not constitute terminating action for the requirements of this AD. (iii) Thereafter following paragraph (f)(1)(i) of this AD, within 150 hours TIS and thereafter at intervals not to exceed 150 hours TIS, accomplish the actions required by paragraph (f)(1)(i) of this AD. Accomplishment of this paragraph constitutes compliance for an instance of paragraph (f)(1)(ii) of this AD. (2) For helicopters without MOD 074775 installed, but with MOD AH 350A087421 or SB EC130-53-029 installed, before the junction frame accumulates 350 hours TIS or within 10 hours TIS, whichever occurs later: (i) Visually inspect for cracking on the junction frame (a) in the upper and lower right-hand side and upper and lower left-hand side areas of the skin cut-out as shown in Detail A, Figure 4 of EASB 05A017, Rev 7. If there is a crack, before further flight, replace or repair the junction frame in accordance with an FAA approved repair procedure. Repairing or replacing the junction frame does not constitute terminating action for the requirements of this AD. (ii) Thereafter following paragraph (f)(2)(i) of this AD, within 10 hours TIS or 250 sling cycles for helicopters that perform external load carrying operations, whichever occurs first, and thereafter at intervals not exceeding 10 hours TIS or 250 sling cycles, whichever occurs first, accomplish the actions required by paragraph (f)(2)(i) of this AD. (iii) Thereafter following paragraph (f)(2)(i) of this AD, within 660 hours TIS and thereafter at intervals not to exceed 660 hours TIS, accomplish the actions required by paragraph (f)(1)(i) of this AD. Accomplishment of this paragraph constitutes compliance for an instance of paragraph (f)(2)(ii) of this AD. (3) For helicopters without MOD 074775 installed, with or without MOD AH 350A087421 or SB EC130-53-029 installed, without MOD 074609 or SB 53-024 installed, and on which the skin of the junction frame area has never been repaired, within 24 months as of the effective date of this AD, install MOD 074775 by following the Accomplishment Instructions, paragraphs 3.B.2.a. through g., of Airbus Helicopters Service Bulletin No. EC130-53-036, Revision 4, dated April, 28, 2020 (ASB EC130-53-036, Rev 4), except where ASB EC130-53-036, Rev. 4 specifies to certain discard parts, you are required to remove those parts from service instead and where ASB EC130-53-036, Rev 4. specifies contacting Airbus Helicopters for corrective action, the corrective action must be accomplished using a method approved by the FAA. Where ASB EC130-53-036, Rev 4, specifies completing the table in Appendix 4.H. under paragraph 3.B.2.g., complete and return the table to Airbus Helicopters within 30 days after installing MOD 074775. Installation of MOD 074775 constitutes terminating action for the inspections required by paragraphs (f)(1) and (2) of this AD. (4) For helicopters without MOD 074775 installed, with MOD 074609 or SB 53-024 installed, or on which the skin of the junction frame area has been previously repaired at any time, within 24 months as of the effective date of this AD, reinforce the junction frame by replacing the two lateral splices which join the skins with four carbon patches (left-hand side, right-hand side, and lower sides) in accordance with an FAA approved corrective procedure. Installation of this reinforcement constitutes terminating action for the inspections required by paragraphs (f)(1) and (2) of this AD. (5) For Model EC130B4 helicopters with MOD 074775 installed or with the reinforcement that is required by paragraph (f)(4) of this AD; and for Model EC130T2 helicopters with MOD 074775 installed or with the reinforcement that is required by paragraph (f)(4) of this AD, but without MOD 074581 installed: (i) Within 600 hours TIS after the installation of MOD 074775 or the reinforcement that is required by paragraph (f)(4) of this AD, and thereafter at intervals not exceeding 600 hours TIS, perform the actions of paragraph (f)(1)(i) of this AD. (ii) If there is a crack, before further flight, replace or repair the junction frame in accordance with an FAA approved repair procedure. Repairing the junction frame does not constitute terminating action for the requirements of this AD.

Special flight permits are prohibited.

You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.

This AD defines the unsafe condition as a crack in the junction frame. This condition could result in failure of the junction frame, which could result in loss of the Fenestron and subsequent loss of control of the helicopter.