Airworthiness Directive · Amendment 39-9570 · Eurocopter Deutschland GmbH (ECD) Model BO-105, BO-105A, BO-105C, BO-105S, and BO-105LS A-1 Helicopters
Eurocopter Deutschland GmbH (ECD) Model BO-105, BO-105A, BO-105C, BO-105S, and BO-105LS A-1 Helicopters
Model BO-105, BO-105A, BO-105C, BO-105S, and BO- 105LS A-1 helicopters with tandem hydraulic unit, part number (P/N) 105-45021, 105-45023, or 105-45028, having valve body manifolds D133-756, D133-756E, ZE1-126-I, ZE2-126, or ZE2-126-1, installed on either Hydraulic System 1 or Hydraulic System 2, certificated in any category.
This amendment adopts a new airworthiness directive (AD), applicable to Eurocopter Deutschland GmbH (ECD) (Eurocopter) Model BO- 105, BO-105A, BO-105C, BO-105S, and BO-105LS A-1 helicopters, that requires a ground test and inspection of the tandem hydraulic switch- over system (switch-over system) for component wear and parts replacement, if necessary. This amendment is prompted by incidents involving Model BO-105 series helicopters in which, during the switch- over from Hydraulic System 1 to Hydraulic System 2, a 3-inch drop in the collective occurred, caused by component wear in the switch-over system. The actions specified by this AD are intended to detect switch- over system component wear, which could result in a sudden drop in the collective and a sudden loss of altitude.
