AD/AMD 50/34 Ice and Rain Protection Outboard Leading Edge Slats (Cth)

AIRWORTHINESS DIRECTIVE

For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (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.

AMD Falcon 50 and 900 Series Aeroplanes

AD/AMD 50/34 Ice and Rain Protection - Outboard
Leading Edge Slats 5/2006

Applicability:

Mystere - Falcon 50 aircraft S/N 2 to 344.

Mystere - Falcon 900 aircraft S/N 1 to 202.

Falcon 900EX aircraft S/N 1 to 96, 98 to 154.

Requirement:

1.    Inspect the outboard slats in accordance with the instructions detailed in F50-475, F900-370, or F900EX-273 as is applicable.

2.    For MF5O which have incorrect slats installed:

(a)   Insert into the Aeroplane Flight Manual           (AFM), Temporary Change (TC) No 61 (AFM reference DTM813 or DTM8O3) or TC No 75 (AFM reference FM813EX).

(b)   Replace the anti-icing manifold according to the instructions in SB F50-478.

The AFM TC inserted in requirement 2(a) of this AD may be removed after carrying out the actions detailed in requirement 2(b) of this AD, which is a terminating action for this AD for MF5O aircraft.

3.    For MF900 and F900EX which have incorrect slats installed:

Repair the manifold according to the instructions detailed in F900-370, or F900EX-273 as is applicable.

This is a terminating action for this AD for the relevant aircraft.

Note:  EASA AD 2006-0037dated 1 February 2006 refers.

Compliance:

1.    Within 330 Flight Hours (FH) or 7 months, whichever comes first, following the effective date of this AD.

2.    (a)   Before further flight.

2.    (b)   Within 1530 FH following the inspection detailed in Requirement 1 of this AD.

3.    Before further flight.

This Airworthiness Directive becomes effective on 11 May 2006.

Background:

Wings of MF5O, MF900, F900EX, F2000 and F2000EX are aerodynamically identical on many points.  Outboard slats on all 5 models have the same external shape and are mechanically interchangeable.  However, hot air anti-icing systems on MF5O are different from those on MF900 I F900EX I F2000 and F2000EX aeroplanes; therefore the slats are functionally not equivalent.

It has been found, during an internal review, that interchangeability of outboard slats between MFSO and MF900 I F900EX or F2000 / F2000EX had been erroneously authorized in some limited cases.  The outboard slats P/N identification plates also appear to be misleading.  Exchanges occurring after delivery of the aircraft may have led to installation of outboard slats of the type not adapted to the aircraft model.  Repairs may have led to installation of anti-icing manifolds (“piccolos tubes”) of a type not adapted to the aircraft model.

This may jeopardize the aircraft, by modifying its anti-icing performance.

The purpose of this Airworthiness Directive (AD) is to check that all aircraft are fitted with the correct outboard slats, and to correct, either by an exchange or a repair, any discrepancy encountered.

James Coyne
Delegate of the Civil Aviation Safety Authority

17 March 2006