Airworthiness Directive · Amendment 39-15837 · Eurocopter France Model EC 155B and EC155B1 Helicopters
Eurocopter France Model EC 155B and EC155B1 Helicopters
This AD applies to Model EC 155B and EC155B1 helicopters with a serial number (S/N) less than 6763, and with optional equipment OP 45C07 (OP 45C07), installed, certificated in any category. OP 45C07 is the helicopter provision kit (electrical and structural mount modifications) used to support installation and operation of a hoist.
(1) To determine if your helicopter has OP 45C07 installed, review aircraft documentation, which should state if OP 45C07 equipment is installed, or
(2) Perform a physical inspection for the existence of the 24 Delta hoist electrical female connector (MIL-C-5015 type connector), which is installed, just forward of the right-hand engine cowling and just below the right engine inlet. Figures 1 and 6 of Eurocopter Emergency Alert Service Bulletin No. 25A085, dated June 1, 2007 (ASB), depict where the connector is located.
We are adopting a new airworthiness directive (AD) for Eurocopter France (Eurocopter) Model EC 155B and EC155B1 helicopters. This AD results from mandatory continuing airworthiness information (MCAI) issued by the European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Community. The MCAI states that "the Airworthiness Directive (AD) is prompted by the discovery of a short circuit evidence in hoist connector "24 Delta" even though the hoist was removed from the rotorcraft. The short circuit generated sufficient heat to ignite the paint on the cooler support cowling near the hoist cut-off connector "24 Delta." This condition, if not corrected, could result in a fire in this area which could propagate to surrounding zones." This AD requires actions that are intended to address this unsafe condition.
Within 7 days, unless already accomplished, do the following:
(1) Determine the orientation of the fixed connector “24 Delta” and if the large contacts are not oriented “aft,” re-orient the fixed connector so that they are facing “aft” by following the Accomplishment Instructions, paragraphs 2.B.1. and 2.B.2.a., of the ASB.
(2) Immediately after each hoist removal until the electrical bonding braid for the fixed hoist connector “24 Delta” is installed, disconnect the hoist power cable by following the Accomplishment Instructions, paragraph 2.B.2.b., of the ASB.
(f) Within 1 month, install an electrical bonding braid for connector “24 Delta” by following the Accomplishment Instructions, paragraph 2.B.2.c., of the ASB.
(g) Factory-implemented modification MOD 0745C82 is acceptable terminating action for the requirements of this AD.
We have used a compliance time of 1 month rather than 3 months because of the serious consequences of an undetected short circuit and potential aircraft fire.
(i) Alternative Methods of Compliance (AMOCs): The Manager, Safety Management Group, FAA, ATTN: George Schwab, Aerospace Engineer, Rotorcraft Directorate, Regulations and Policy Group, Fort Worth, Texas 76193-0111, telephone (817) 222-5114, fax (817) 222-5961, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19.
