Airworthiness Directive · Amendment 39-11602 · Dassault Model Mystere-Falcon 50 Series Airplanes
Dassault Model Mystere-Falcon 50 Series Airplanes
Model Mystere-Falcon 50 series airplanes, serial numbers 251, 253, and subsequent; equipped with Allied-Signal TFE731-40 engines; certificated in any category; except airplanes that have been modified in accordance with Dassault Service Bulletin F50-276, dated June 24, 1998, or airplanes on which Dassault Modification M2193 was installed in production.
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (d) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment supersedes an existing airworthiness directive (AD), applicable to certain Dassault Model Mystere-Falcon 50 series airplanes, that currently requires a revision to the Limitations section of the FAA-approved Airplane Flight Manual (AFM) to include procedures to use certain values to correctly gauge the minimum allowable N1 speed of the operative engines during operation in icing conditions. This amendment adds a new requirement for operators to adjust the thrust reverser handle stop, install new wiring, and modify the Digital Electronic Engine Control (DEEC) software, which terminates the AFM revision. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent flightcrew use of erroneous N1 thrust setting information displayed on the Engine Indication Electronic Display (EIED), which could result in in-flight shutdown of engine(s).
To prevent in-flight shutdown of the engine(s) due to the flightcrew using erroneous N1 speed values displayed on the Engine Indication Electronic Display (EIED), accomplish the following:
(a) Within 1 day after November 18, 1997 (the effective date of AD 97-21-16, amendment 39-10202), revise the Limitations Section of the FAA-approved Airplane Flight Manual (AFM) to add the following. This may be accomplished by inserting a copy of this AD in the AFM.
“Operation in Icing Conditions:
The N1 speed of the operating engines must not be less than the minimum values specified in Normal Section 4, Sub-section 140, Page 2, of the AFM.”
(b) Within 6 months after the effective date of this AD, adjust the thrust reverser handle stop, install new “push-light” wiring on the instrument panel, and modify the Digital Electronic Engine Control (DEEC) software; in accordance with Dassault Service Bulletin F50-276, dated June 24, 1998. Accomplishment of such actions constitutes terminating action for the AFM revision required by paragraph (a) of this AD. Following accomplishment of the terminating action, the AFM revision required by paragraph (a) of this AD may be removed from the AFM.
Note 2: Dassault Service Bulletin F50-276 refers to Allied Signal Service Bulletin TFE731-76-5107, dated December 24, 1997, as an additional source of service information for accomplishment of the modification.
(c) As of the effective date of this AD, no person shall install DEEC software, part number 2118882-4002, on any airplane.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Aircraft
