Airworthiness Directive · Amendment 39-17410 · Main rotor gearbox and 6520: tail rotor gearbox
Eurocopter France Helicopters
This AD applies to Eurocopter Model AS332C, AS332L, AS332L1, AS332L2, and EC225LP helicopters, certificated in any category.
We are adopting an airworthiness directive (AD) for Eurocopter France (Eurocopter) Model AS332C, AS332L, and AS332L1 helicopters and superseding an AD for Model AS332L2 and EC225LP helicopters. This AD requires inspecting the chip detector and modifying the chip collector, both installed on the main gearbox (MGB). This AD is prompted by an investigation which showed a failure within the epicyclic reduction gear module (epicyclic module) resulted in the rupture of the MGB case and separation of the main rotor head of a Model AS332L2 helicopter. These actions are intended to prevent failure of the MGB and subsequent loss of control of the helicopter.
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.
(1) For Model AS332L2 and EC225LP helicopters, before further flight:
(i) Determine from the maintenance records whether, within the last 200 hours time-in-service (TIS), the “CHIP” detector light illuminated because of a metal particle on the chip detector of the MGB epicyclic module (module), and if so, whether the “CHIP” detector light stayed illuminated after the “CHIP” detector switch was turned to the “CHIP PULSE” setting to activate the “fuzz burn-off” feature.
(A) If the maintenance records indicate that the “CHIP” detector light illuminated because of a metal particle on the chip detector of the module, and the “CHIP” detector light stayed illuminated after the “CHIP” detector switch was turned to the “CHIP PULSE” setting, replace the module with an airworthy module before further flight.
(B) If the maintenance records do not indicate which “CHIP” detector caused the “CHIP” detector light to illuminate, or whether the detector light stayed illuminated after the “CHIP” detector switch was turned to the “CHIP PULSE” setting, replace the module with an airworthy module before further flight.
(ii) Inspect the module magnetic chip detector electrical circuit and determine whether the system is functioning properly, including whether the “CHIP” detector light annunciates on the instrument panel (Vehicle Monitoring System Screen).
(iii) After accomplishing paragraph (f)(1)(i)-(ii) of this AD, thereafter, if the “CHIP” detector light illuminates, stays illuminated after the chip detector switch is turned to the “CHIP PULSE” setting, and there is a metal particle on the module magnetic chip detector (rather than the main reduction gear (lower MGB), the flared housing (mast assembly), the IGB, or the TGB chip detectors) that caused the “CHIP” detector light to illuminate, replace the module with an airworthy module.
(iv) Within 50 hours TIS, remove, modify, reidentify, and reinstall the chip collector as shown in Figures 2 through 5, and in accordance with the Accomplishment Instructions, paragraph 2.B.1.b.1 through 2.B.1.b.5, of Eurocopter Emergency Alert Service Bulletin (EASB) No. 05.00.81, Revision 3, dated July 13, 2012, or Eurocopter EASB No. 05A017, Revision 3, dated July 13, 2012, for your model helicopter.
(v) Before installing a MGB, modify, reidentify, and reinstall the chip collector in accordance with paragraph (f)(1)(iv) of this AD.
(2) Within 25 hours TIS, and thereafter at intervals not exceeding 25 hours TIS:
(i) For Model AS332C, L, and L1 helicopters with non-electrical chip detectors and electrical chip detectors without a caution light on the instrument panel, inspect the IGB, TGB, tapered housing, and MGB bottom casing chip detectors for a chip or metallic particle.
(ii) For Model AS332L2 helicopters with non-electrical chip detectors and electrical chip detectors without a caution light on the instrument panel, inspect the module, main rotor mast tapered housing, IGB, and TGB chip detectors for a chip or metallic particle.
(3) Within 50 hours TIS, and thereafter at intervals not exceeding 50 hours TIS:
(i) For Model AS332C, L, and L1 helicopters with electrical chip detectors with a caution light on the instrument panel, inspect the MGB bottom casing, TGB, and IGB chip detectors for a chip or metallic particle.
(ii) For Model AS332L2 helicopters with electrical chip detectors with a caution light on the instrument panel, inspect the MGB bottom casing chip detector for a chip or magnetic particle.
(iii) For Model EC225LP helicopters, inspect the MGB, IGB, and TGB chip detectors for a chip or magnetic particle. If there is a chip or magnetic particle, determine whether the “CHIP” caution light illuminates on the “Vehicle” page of the Vehicle Management System. If the “CHIP” caution light does not illuminate on the “Vehicle” page, perform a fault analysis.
