AD 2021-07-05 Retains All Inspections For Certain Serial-Numbered MRBs

The FAA is superseding Airworthiness Directive (AD) 2007-26-52 which applied to certain Agusta S.p.A. (now Leonardo) Model A109C, A109E, and A109K2 helicopters. AD 2007-26-52 required inspecting for swelling, deformation, bonding separation, and for a crack on each main rotor blade (MRB) with a certain part-numbered tip cap installed, and removing the MRB from service before further flight if any of these conditions exist and exceed the prescribed limits.

This AD retains all inspections for certain serial-numbered MRBs, but for MRBs with a certain tip cap installed, this AD requires dye-penetrant inspections rather than visual inspections. This AD was prompted by additional reports of in-flight loss of part of a tip cap. The FAA is issuing this AD to address the unsafe condition on these products. This AD becomes effective April 8, 2021.

Supplementary Information: The FAA issued Emergency AD 2007-26-52 on December 20, 2007 and published it as a Final rule; request for comments on May 9, 2008, as Amendment 39-15519 (73 FR 26316). AD 2007-26-52 applied to Agusta S.p.A. (now Leonardo) Model A109C, A109E, and A109K2 helicopters with an MRB part number (P/N) 709-0103-01-all dash numbers installed. AD 2007-26-52 required, for any MRB with a serial number (S/N) with a prefix of either “EM-” or “A5-”, except a MRB with a tip cap P/N 709-0103-29-109, within 10 hours time-in-service (TIS) and thereafter at intervals not to exceed 25 hours TIS:

• A tap inspection of the upper and lower sides of each tip cap and in the tip cap to blade bond area for bonding separation;
• A visual inspection of the upper and lower side of each blade tip cap for swelling or deformation; and
• A dye-penetrant inspection of the tip cap leading edge along the welded joint line of the upper and lower tip cap skin shells for a crack.

For any MRB with a tip cap P/N 709-0103-29-109 installed, the AD required visually inspecting for a crack on the leading edge at the welded bead (joint line of shells) using a 10x or higher power magnifying glass, and if there is damage other than a crack, inspecting the area using a dye-penetrant inspection method, within the following compliance times:

• For a tip cap P/N 709-0103-29-109 with 600 or more hours TIS, inspect within the next 5 hours TIS or 30 days, whichever occurs first, and thereafter at intervals not to exceed 50 hours TIS; or
• For a tip cap P/N 709-0103-29-109 with less than 600 hours TIS, inspect before reaching 600 hours TIS, and thereafter, at intervals not to exceed 50 hours TIS.

AD 2007-26-52 also required replacing the MRB if swelling, deformation, a crack, or bonding separation that exceeds the prescribed limits is found in an MRB with an affected prefix, except an MRB with a tip cap P/N 709-0103-29-109. The MRB must be replaced with an airworthy MRB before further flight. If a crack is found in a MRB with tip cap P/N 709-0103-29-109, then AD 2007-26-52 required replacing the MRB before further flight. The actions were required to be accomplished in accordance with the manufacturer's service information.

AD 2007-26-52 was prompted by EASA AD 2007-0306-E, dated December 14, 2007 (EASA AD 2007-0306-E). EASA, which is the Technical Agent for the Member States of the European Union, notified the FAA that an unsafe condition may exist on Agusta Model A109C, A109E, and A109K2 helicopters. EASA advises that an incident occurred in which a Model A109E helicopter lost part of the tip of the MRB due to fracture of the welded bead (joint line of shells). The manufacturer advised that the investigation relating to this tip cap failure was still ongoing.

FMI: www.regulations.gov