Airworthiness Directive · Amendment 39-11696 · General Electric Company GE90 Series Turbofan Engines
General Electric Company GE90 Series Turbofan Engines
Superseded. A later AD replaced this one: AD 2002-04-11. Comply with the one in force.
General Electric Company (GE) GE90-76B/ -77B/ -85B/ -90B/ -92B series turbofan engines, installed on but not limited to Boeing 777 series airplanes.
Note 1: This airworthiness directive (AD) applies to each engine 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 engines 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 (c) 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 General Electric Company GE90 series turbofan engines, that currently requires revisions to the Airworthiness Limitations Section (ALS) of the manufacturer's Instructions for Continued Airworthiness (ICA) to include required enhanced inspection of selected critical life-limited parts at each piece-part exposure. This action adds additional critical life-limited parts for enhanced inspection. This amendment is prompted by additional focused inspection procedures for other critical life-limited rotating engine parts that have been developed by the manufacturer. The actions specified by this AD are intended to prevent critical life-limited rotating engine part failure, which could result in an uncontained engine failure and damage to the airplane.
To prevent critical life-limited rotating engine part failure, which could result in an uncontained engine failure and damage to the airplane, accomplish the following:
(a) Within the next 30 days after the effective date of this AD, revise the manufacturer's Airworthiness Limitations Section of the Instructions for Continued Airworthiness (ICA), and for air carrier operations revise the approved continuous airworthiness maintenance program, by adding the following:
(1) Perform inspections of the following parts at each piece-part opportunity in accordance with the instructions provided in the applicable manual provisions:
| Part nomenclature | Part No. (P/N) | Inspect per engine manual chapter |
|---|---|---|
| For GE90 Engines: | ||
| HPCR, Disk, Stage 7 | All | 72-31-07-200-001-001 Fluorescent Penetrant Inspection, and 72-31-07-200-001-001 Eddy Current Inspection of the Rim Boltholes. |
| HPTR, Interstage Seal | All | 72-53-03-200-001-001 Fluorescent Penetrant Inspection, and 72-53-03-200-001-001 Eddy Current Inspection of the Bore. |
| Fan Disk, Stage 1 | All | 72-21-03-200-001-001 Fluorescent Penetrant Inspection, and 72-21-03-200-001-001 Eddy Current Inspection of the Bore, and 72-21-03-200-001-001 Ultrasonic Inspection of Dovetail Slots. |
| HPTR Disk, Stage 1 | All | 72-53-02-200-001-002 Fluorescent Penetrant Inspection, and 72-53-02-200-001-002 Eddy Current Inspection of the Bore. |
| HPTR Disk, Stage 2 | All | 72-53-04-200-001-004 Fluorescent Penetrant Inspection, and 72-53-04-200-001-004 Eddy Current Inspection of the Bore. |
| HPCR Disk, Stage 1 | All | 72-31-05-200-001-001 Fluorescent Penetrant Inspection, and 72-31-05-200-001-001 Eddy Current Inspection of the Bore, and 72-31-05-200-001-001 Eddy Current Inspection of the Dovetail Slots. |
| HPCR Spool, Stage 2-6 | All | 72-31-06-200-001-001 Fluorescent Penetrant Inspection, and 72-31-06-200-001-001 Eddy Current Inspection of the S2 Dovetail Slots. |
| HPCR Seal, Compressor Discharge Pressure | All | 72-31-09-200-001-001 Fluorescent Penetrant Inspection, and 72-31-09-200-001-001 Eddy Current Inspection of the Boltholes. |
(2) For the purposes of these mandatory inspections, piece-part opportunity means:
(i) The part is considered completely disassembled when accomplished in accordance with the disassembly instructions in the manufacturer's engine manual; and
(ii) The part has accumulated more than 100 cycles in service since the last piece-part opportunity inspection, provided that the part was not damaged or related to the cause for its removal from the engine.”
(b) Except as provided in paragraph (c) of this AD, and notwithstanding contrary provisions in section 43.16 of the Federal Aviation Regulations (14 CFR 43.16), these mandatory inspections shall be performed only in accordance with the Airworthiness Limitations Section of the manufacturer's ICA.
