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94-23-09: High Pressure Compressor Disks

FAA order 94-23-09 is an airworthiness directive in force since January 6, 1995. The FAA's subject line: High Pressure Compressor Disks. It names the Rolls-Royce SPEY 506-14, Rolls-Royce SPEY 511-8 engines: about 16 aircraft on the U.S. register today across them, though an order usually covers particular versions or serial numbers rather than every one. System: engine.

What it applies to as the FAA lists it

Kind of product: Engine
Makes: Rolls-Royce Deutschland Ltd & Co KG
Models: Spey 506-14, Spey 506-14A, Spey 506-14D, Spey 511-14, Spey 511-14W, Spey 555-15, Spey 555-15H, Spey 555-15N, Spey 555-15P
Engine series: Rolls-Royce SPEY 506-14 1 aircraft
Rolls-Royce SPEY 511-8 15 aircraft

Dates and paperwork

In force since: January 6, 1995
Published: December 7, 1994
Docket: 93-ANE-31
Status: Current
The FAA's document: Read the order on the FAA's site

The FAA's summary their words, unchanged

This amendment supersedes telegraphic airworthiness directive (AD) T89-02-52, which superseded Telegraphic AD T88-22-51 (AD), applicable to Rolls-Royce, plc (R-R) Spey series turbofan engines. Telegraphic AD T88-22-51 reduced cyclic life limits for seventh stage high pressure compressor (HPC) disks from 40,000 total part cycles in service (TPC) to 35,000 TPC for the R-R Spey Model 506-14 and -14D engines. Telegraphic AD T89-02-52 currently requires repetitive inspections or further reduced cyclic life limits for seventh stage HPC disks. This amendment increases the AD's effectivity to include additional R-R Spey engine models, eliminates the option for repetitive inspections, and further reduces the cyclic life limits. This amendment is prompted by further investigation into disk bore cracking that was caused by corrosion. The actions specified by this AD are intended to prevent a seventh stage HPC disk burst due to cracking attributed to corrosion, which may result in an uncontained engine failure. The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of January 6, 1995.

The order itself the regulatory text, as published

Show the full text (2,858 characters)

94-23-09  Rolls-Royce, plc:  Amendment 39-9072.  Docket 93-ANE-31.  Supersedes Telegraphic AD T89-02-52, dated January 26, 1989. 
	Applicability:  Rolls-Royce, plc (R-R) Spey 506-14 series, 511-14 series, and 555-15 series turbofan engines installed on but not limited to British Aerospace BAC 1-11 and Fokker F28 aircraft. 
	Compliance:  Required as indicated, unless accomplished previously. 
	To prevent a seventh stage high pressure compressor (HPC) disk burst due to cracking attributed to corrosion, which may result in an uncontained engine failure, accomplish the following: 
	(a)	For seventh stage HPC disks that on the effective date of this airworthiness directive (AD) exceed the revised cyclic life limits described in R-R Mandatory Service Bulletin (SB) Sp72- 1034, Revision 1, dated May 4, 1990, remove from service and replace with a serviceable part within 60 days after the effective date of this AD. 
	(b)	For seventh stage HPC disks that on the effective date of this AD do not exceed the revised cyclic life limits described in R-R Mandatory SB Sp72-1034, Revision 1, dated May 4, 1990, remove from service and replace with a serviceable part:  either prior to exceeding the revised cyclic life limits, or within 60 days after the effective date of this AD, whichever occurs later. 
	(c)	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, Engine Certification Office. The request should be forwarded through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Engine Certification Office. 
	NOTE:  Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Engine Certification Office. 
	(d)	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) tooperate the aircraft to a location where the requirements of this AD can be accomplished. 
	(e)	The actions required by this AD shall be done in accordance with the following R-R service bulletin: 


Document No.
Pages
Revision
Date
 Mandatory 



SB No. Sp72-1034
1-3
1
May 4, 1990 
Total pages:  3. 




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 Service Manager, Spey engines, Rolls-Royce, plc, East Kilbride, Glasgow G74 4PY, Scotland.  Copies may be inspected at the FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. 
	(f)	This amendment becomes effective on January 6, 1995.

Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of October 7, 2026. Connections as data: /graph/directive/94-23-09.json · aircraft systems.