Aircraft
Certification Service Washington, DC U.S. Department of Transportation Federal Aviation Administration
SW-08-30
June 23, 2008
This is information only. Recommendations
aren’t mandatory.
Introduction
This Special Airworthiness Information Bulletin alerts you, owners and
operators of Eurocopter France (Eurocopter) Model AS332L1, AS332L2, AS
365 N3, EC155B1, and EC225LP helicopters, of uncontrolled deployment of
the CPI 503 beacon in flight and on the ground.
Background
There have been several reports of inadvertent and uncontrolled
deployment of the CPI 503 beacon, both in flight and on the ground.
These conditions have been traced to two different causes:
On the Eurocopter Model
AS332L1, AS332L2, and EC225LP helicopters, the ELT water-activated
switch is located in an area highly exposed to splashing water when the
helicopter is cleaned and in rainy weather. This condition is leading
to untimely deployment of the beacon.
On the Eurocopter Model
AS332L1, AS332L2, AS 365 N3, EC155B1, and EC225LP helicopters, faulty
electrical bonding can make the system sensitive to interference (radio
waves, electrostatic discharges, etc.) and can cause unwanted
deployment of the beacon. Also, the risk of an uncontrolled beacon
deployment is increased during hoisting or sling operations, due to
electrostatic discharges that may occur if the cable contacts the
ground.
Recommendations
Due to the potential consequences of an inadvertent or uncontrolled
deployment of a CPI beacon, we recommend that you follow the procedures
in Eurocopter Alert Service Bulletin (ASB) AS332 No. 25.01.97, ASB
EC225 No. 25A028, AS365 No. 25.00.91, or EC155 No. 25A087, as
applicable to your helicopter. All of the ASBs are dated May 26, 2008.