AD/ERJ-170/10 Amdt 1 Firewall Hydraulic Shutoff Valves (Cth)

AIRWORTHINESS DIRECTIVE

On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/ERJ-170/10 and issues the following AD under subregulation 39.001(1) of CASR 1998.  The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Embraer ERJ-170 Series Aeroplanes

AD/ERJ-170/10 Amdt 1 Firewall Hydraulic Shutoff Valves 11/2007

Applicability:

Embraer ERJ-170( ) aircraft fitted with firewall hydraulic shutoff valves part number (P/N) 975287-3 or P/N 975287-5.

Requirement:

Perform an operational check in accordance with Embraer Service Bulletin No. 170-29-0013 original issue, or further ANAC approved revisions, for proper operation of the firewall hydraulic shutoff valves P/N975287-3 or P/N 975287-5.  If necessary, replace the faulty hydraulic shutoff valve with another one bearing the same P/N.

For the purpose of this AD, an operational check is: “A task to determine that an item is fulfilling its intended purpose.  The check does not require quantitative tolerances.  This is a failure finding task.”

Note:  Agência Nacional De Aviação Civil - Brazil Airworthiness Directive AD No. 2007-02-01R1 dated 27 August 2007 refers.

Compliance:

Remains unchanged as detailed in the original issue of this AD as: Within the next 600 flight hours after 7 June 2007, and thereafter at intervals that do not exceed 600 flight hours.

This Amendment becomes effective on 25 October 2007.

Background:

Periodic operational check of the firewall hydraulic shutoff valves, made during routine maintenance, has revealed that the failure rate of that component is significantly higher than expected.  Such a dormant failure, when combined with further possible failures, such as engine fire, may lead to an unacceptable reduction of safety margins.

This amendment adds an additional part number valve to the applicability section with no change to the requirement section.

The original issue of this AD became effective 7 June 2007.

Charles Lenarcic
Delegate of the Civil Aviation Safety Authority

7 September 2007