“Category II and III operations are proh
“Category II and III operations are prohibited.”, and
“Category II and III operations are prohibited.”, and
(ii) Revise Limitations Section of the AFM to include the following statement:
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This directive requires operators of aeroplanes with RIA‑35B ILS receivers P/N 066-50006-0101 to inspect the receivers’ internal fault memory at specified intervals and to not conduct Category II and III operations until the AFM/placard is amended to show that prohibition. If fault codes “N1” or “Nm” are found, the receiver must be replaced or modified per AlliedSignal SB M-4426 Rev 3; modified units are re‑identified P/N 066-50006-1101 and remove the need for repetitive inspections. Operators bear inspection and modification/replacement costs.
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Direct links to the current provisions in AD/B747/190 Amdt 1 - Instrument Landing System Receivers.
(ii) Revise Limitations Section of the AFM to include the following statement:
Sourced from the Federal Register of Legislation (legislation.gov.au), CC BY 4.0.
(ii) Revise Limitations Section of the AFM to include the following statement:
(This may be accomplished by inserting a copy of this Directive into the AFM)
2. If, during the Requirement 1 (a) inspection, fault code “N1” or “Nm” is found, either replace the existing ILS receiver with a new or serviceable ILS receiver having the same P/N or with an ILS receiver that has been modified to P/N 066- 50006-1101 in accordance with AlliedSignal Electronic and Avionics Systems Service Bulletin (SB) M-4426 (RIA-35B-34-6) Revision 3 dated May 1998.
3. A RIA-35B ILS receiver P/N 066-50006-0101, that has been found to be discrepant (that is on which fault codes “N1” or “Nm” were found during an inspection of the internal fault memory) shall not be installed on any aeroplane unless the discrepancy has been corrected by modifying the ILS receiver in accordance with SB M-4426 (RIA-35B-34-6) Revision 3.
4. Replace all existing RIA-35B ILS receivers, P/N 066-50006-0101, with RIA-35B receivers that have been modified in accordance with SB M-4426 (RIA-35B-34-6) Revision 3 and that have had their P/N’s converted to 066-50006-1101. This constitutes terminating action for the Requirement 1.a. repetitive inspection and allows the removal of the Requirement 1.b. placard, together with any required amendment to the Flight Manual Limitations Section on this subject.
Note 2: FAA AD 99-10-14 Amdt 39-11167 refers.
Compliance: 1. a. Remains unchanged from the original Compliance 1 as ‘Prior to 2 October 1998 and thereafter at intervals not to exceed 64 flight cycles’.