AD 98-03-18 Airworthiness Directives; Fokker Model F28 Mark 0100 and 0070 Series Airplanes

Models named: F28 Mark 0100, 0070 series. Read the applicability below — it usually turns on serial or part numbers too.

All Model F28 Mark 0100 and 0070 series airplanes, certificated in any category. Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been 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 (g) 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.

Required as indicated, unless accomplished previously. To prevent failures of the emergency direct current (DC)/ alternating current (AC) bus power supply, which could reduce the ability of the flightcrew to control the airplane, accomplish the following: Restatement of Actions Required by AD 95-21-10, Amendment 39-9396 Note 2: For Model F28 Mark 0070 series airplanes, on which the procedures specified in Fokker Service Bulletins SBF100-24-033 and SBF100-24-034 have been accomplished, the AFM revisions required by paragraphs (a), (b), and (c) of this AD may be removed from the AFM. Note 3: For Model F28 Mark 0100 series airplanes, on which the procedures specified in Fokker Service Bulletin SBF100-24-030 have not been accomplished, or on which the procedures specified in Fokker Service Bulletin SBF100-24-033 have been accomplished; the AFM revisions required by paragraphs (a), (b), and (c) of this AD may be removed from the AFM. (a) For all airplanes: Within 7 days after October 27, 1995 (the effective date of AD 95-21-10, amendment 39-9396), revise the Abnormal Procedures Section of the FAA-approved Airplane Flight Manual (AFM) to include the following statement. This may be accomplished by inserting a copy of this AD in the AFM. ``Section 4--Abnormal Procedures Add to Sub-section 4.04--Electrical Power STANDBY ANNUNCIATOR PANEL RED AC SUPPLY LIGHT ``ON'' On overhead electrical panel: GEN LOAD..........................................................CHECK If all generator loads are approximately zero: LOSS OF AC SUPPLY PROCEDURE.......................................APPLY If not all generator loads are approximately zero: DC EMER BUS SUPPLY TRU3 CIRCUIT BREAKER...........................CHECK If circuit breaker has tripped: DC EMER BUS SUPPLY TRU3 CIRCUIT BREAKER...........................RESET --If reset is unsuccessful: L and R AUDIO......................................................ALTN Anticipate the effects of an eventual EMER DC BUS failure, see EMER DC BUS FAULT procedure. If circuit breaker has not tripped: L and R AUDIO......................................................ALTN Anticipate the effects of an eventual EMER DC BUS failure, see EMER DC BUS FAULT procedure.'' (b) For all airplanes: Within 7 days after October 27, 1995, revise the Normal Procedures Section of the FAA-approved AFM to include the following statement. This may be accomplished by inserting a copy of this AD in the AFM. ``Section 5--Normal Procedures Insert in front of Sub-section 5.01.01--Take-off After engine start, select the Standby Annunciator Panel (SAP) backup mode ON via the BACKUP p/b at the SAP. Keep the SAP in the backup mode for the whole duration of flight until engine shutdown. Monitor the SAP. Note: Failure conditions as presented on the SAP bypass the Flight Warning Computer (FWC) are not subject to alert inhibition. Be aware that the red LG light on the SAP will illuminate in case one or both thrustlever(s) are below the minimum take-off position and the landing gear is not down.'' (c) For all Model F28 Mark 0070 series airplanes; and Model F28 Mark 0100 series airplanes, in pre-SBF100-24-009 configuration or in post SBF100-24-030 configuration: Within 7 days after October 27, 1995, revise the Abnormal Procedures Section of the FAA-approved AFM to include the following statement. This may be accomplished by inserting a copy of this AD in the AFM. ``Section 4--Abnormal Procedures Add to Sub-section 4.04--Electrical Power ERRATIC ELECTRICAL SYSTEM BEHAVIOR In case of continuous rattling sound, caused by the fast switching of relays and accompanied by blanking or erratic behavior of the three displays on the electric panel: BATTERIES...............................SELECT MOMENTARILY OFF, THEN ON AFFECTED SYSTEMS........................................RESTORE IF REQD If the red AC SUPPLY light on the SAP comes ON: SAP RED AC SUPPLY LIGHT `ON' PROCEDURE..........................APPLY'' New Actions Required by This AD (d) For Model F28 Mark 0070 and 0100 series airplanes, as listed in Fokker Service Bulletin SBF100-24-032, dated September 12, 1996, or Revision 1, dated April 25, 1997, or Revision 2, dated July 28, 1997: Within 12 months after the effective date of this AD, modify the DC bus transfer system in accordance with Fokker Service Bulletin SBF100-24-032, dated September 12, 1996; or Revision 1, dated April 25, 1997; or Revision 2, dated July 28, 1997. Prior to further flight following accomplishment of this modification, accomplish paragraph (e) of this AD. Note 4: For Fokker Model F28 Mark 0070 series airplanes, Fokker Service Bulletin SBF100-24-032 recommends prior or concurrent accomplishment of the procedures specified in Fokker Service Bulletin SBF100-24-034, dated October 17, 1995, or Revision 1, dated September 12, 1996 (which is currently required by AD 96-26-03, amendment 39-9866). (e) Revise the Abnormal Procedures Section of the FAA-approved AFM to include the following statement. This may be accomplished by inserting a copy of this AD in the AFM. ``Section 4--Abnormal Procedures Sub-section 4.04.05--Electrical Power--Bus Equipment List Insert a marker {time} in each Bus Equipment List table, at the top of the column marked: EMERGENCY--DC. Add the following note at the beginning of the affected sub- section: Note: {time} When an ``EMER DC BUS'' fault is presented on the multi-function display unit (MFDU), check whether the electric panel digital readouts are operative. If operative, the EMER DC bus is supplied from the battery chargers via the batteries for 90 minutes and all services connected to this bus will remain available. After this time period, batteries will start to discharge and the effects of an EMER DC BUS fault should then be expected. If inoperative, continue with the EMER DC BUS FAULT procedure. At the bottom of each succeeding page (Bus Equipment List table) of sub-section 4.04.05, make a clear reference to the note marked {time} located at the beginning of sub-section 4.04.05.'' (f) Accomplishment of the modification in accordance with paragraph (d) of this AD constitutes terminating action for the requirements of paragraphs (a), (b), and (c) of this AD. After the modification has been accomplished, the previously required AFM revision may be removed from the AFM. (g) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, International Branch, ANM-116, FAA, [[Page 6069]] Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, International Branch, ANM-116. Note 5: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116. (h) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. (i) The actions shall be done in accordance with the following Fokker service bulletins, which contain the specified effective pages: ---------------------------------------------------------------------------------------------------------------- Service bulletin referenced and Revision level shown date Page No. on page Date shown on page ---------------------------------------------------------------------------------------------------------------- SBF100-24-032, September 12, 1996. 1-46................ Original............. September 12, 1996. SBF100-24-032, Revision 1, April 1-4, 7-62........... 1.................... April 25, 1997. 25, 1997. 5-6................. Original............. September 12, 1996. SBF100-24-032, Revision 2, July 1-2, 13, 15, 29-30.. 2.................... July 28, 1997. 28, 1997. 3-4, 7-12, 14, 16- 1.................... April 25, 1997. 28, 31-62. 5-6................. Original............. September 12, 1996. ---------------------------------------------------------------------------------------------------------------- This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Fokker Services B.V., Technical Support Department, P.O. Box 75047, 1117 ZN Schiphol Airport, the Netherlands. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. Note 6: The subject of this AD is addressed in Dutch airworthiness directive BLA 1995-089/4, dated September 30, 1996. (j) This amendment becomes effective on March 23, 1998. Issued in Renton, Washington, on January 30, 1998. Stewart R. Miller, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 98-2825 Filed 2-5-98; 8:45 am] BILLING CODE 4910-13-P