Airworthiness Directives; Rolls-Royce Limited, Aero Division- Bristol/S.N.E.C.M.A. Olympus 593 Series Turbojet Engines

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-07-AD; Amendment 39-10753; AD 98-19-11]

RIN 2120-AA64

Airworthiness Directives; Rolls-Royce Limited, Aero Division-

Bristol/S.N.E.C.M.A. Olympus 593 Series Turbojet Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that

is applicable to Rolls-Royce Limited, Aero Division-Bristol/

S.N.E.C.M.A. Olympus 593 series turbojet engines. This action requires

initial and repetitive X-ray and ultrasonic inspections of exhaust

diffuser vanes for corrosion and cracks, and, if necessary, removal

from service of cracked exhaust diffusers and replacement with

serviceable parts. This amendment is prompted by reports of 17 turbine

exhaust diffuser modules with one or more exhaust diffuser vanes

cracked. The actions specified in this AD are intended to prevent

exhaust diffuser vane failure, which could result in an adverse effect

on the engine oil and reheat systems, possibly causing an inflight

engine shutdown or damage to the aircraft.

DATES: Effective October 1, 1998.

The incorporation by reference of certain publications listed in

the regulations is approved by the Director of the Federal Register as

of October 1, 1998.

Comments for inclusion in the Rules Docket must be received on or

before November 16, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

Administration (FAA), New England Region, Office of the Regional

Counsel, Attention: Rules Docket No. 98-ANE-07-AD, 12 New England

Executive Park, Burlington, MA 01803-5299. Comments may also be sent

via the Internet using the following address: ``9-ad-

[email protected]''. Comments sent via the Internet must contain

the docket number in the subject line.

The service information referenced in this AD may be obtained from

Rolls-Royce, PO Box 3, Filton, Bristol BS12 7QE, England; telephone 01-

17-979-1234, fax 01-17-979-7575. This information may be examined at

the FAA, New England Region, Office of the Regional 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.

FOR FURTHER INFORMATION CONTACT: Jason Yang, Aerospace Engineer, Engine

Certification Office, FAA, Engine and Propeller Directorate, 12 New

England Executive Park, Burlington, MA 01803-5299; telephone (781) 238-

7747, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: The Civil Aviation Authority (CAA), which is

the airworthiness authority for the United Kingdom (UK), recently

notified the Federal Aviation Administration (FAA) that an unsafe

condition may exist on Rolls-Royce Limited, (R-R)Aero Division-Bristol/

S.N.E.C.M.A. Olympus 593 Mk. 610-14-28 turbojet engines. The CAA

advises that they have received reports of 17 turbine exhaust diffuser

modules containing at least one cracked exhaust diffuser vane. In some

cases the exhaust diffuser vanes peeled back due to vane leading edge

cracking. If the exhaust diffuser vanes peel back, they can possibly

expose the engine oil and reheat systems imbedded inside the exhaust

diffuser vane and result in bearing sump damage. There are currently no

affected engines operated on aircraft of U.S. registry. This AD, then,

is necessary to require accomplishment of the required actions for

engines installed on aircraft currently of foreign registry that may

someday be imported into the U.S. Accordingly, the FAA has determined

that notice and prior opportunity for comment are unnecessary and good

cause exists for making this amendment effective in less than 30 days.

This condition, if not corrected, could result in exhaust diffuser vane

failure, which could result in an adverse effect on the engine oil and

reheat systems, possibly causing an inflight engine shutdown or damage

to the aircraft.

R-R has issued Service Bulletin (SB) No. OL.593-72-9042-422,

Revision 1, dated May 23, 1997, that specifies procedures for X-ray

inspections of exhaust diffuser vanes for cracks and corrosion, and if

found cracked, removal from service of the exhaust diffuser and

[[Page 49419]]

replacement with a serviceable part. In addition, R-R has issued SB No.

OL.593-72-9047-423, dated January 31, 1997, that specifies procedures

for ultrasonic inspections of corroded exhaust diffuser vanes for

leading edge cracks, and if the exhaust diffuser fails inspection,

removal from service of the exhaust diffuser and replacement with a

serviceable part. The CAA classified these SBs as mandatory and issued

ADs 005-01-97 and 006-01-97 in order to assure the airworthiness of

these engines in the UK.

This engine model is manufactured in the UK and is type

certificated for operation in the United States under the provisions of

Sec. 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the

applicable bilateral airworthiness agreement. Pursuant to this

bilateral airworthiness agreement, the CAA has kept the FAA informed of

the situation described above. The FAA has examined the findings of the

CAA, reviewed all available information, and determined that AD action

is necessary for products of this type design that are certificated for

operation in the United States.

Since an unsafe condition has been identified that is likely to

exist or develop on other engines of the same type design registered in

the United States, the AD requires initial and repetitive X-ray and

ultrasonic inspections of exhaust diffuser vanes for cracks and

corrosion, and, if necessary, removal from service of the exhaust

diffuser and replacement with a serviceable part. The actions would be

required to be accomplished in accordance with the SBs described

previously.

Since a situation exists that requires the immediate adoption of

this regulation, it is found that notice and opportunity for prior

public comment hereon are impracticable, and that good cause exists for

making this amendment effective in less than 30 days.

Comments Invited

Although this action is in the form of a final rule that involves

requirements affecting flight safety and, thus, was not preceded by

notice and an opportunity for public comment, comments are invited on

this rule. Interested persons are invited to comment on this rule by

submitting such written data, views, or arguments as they may desire.

Communications should identify the Rules Docket number and be submitted

in triplicate to the address specified under the caption ADDRESSES. All

communications received on or before the closing date for comments will

be considered, and this rule may be amended in light of the comments

received. Factual information that supports the commenter's ideas and

suggestions is extremely helpful in evaluating the effectiveness of the

AD action and determining whether additional rulemaking action would be

needed.

Comments are specifically invited on the overall regulatory,

economic, environmental, and energy aspects of the rule that might

suggest a need to modify the rule. All comments submitted will be

available, both before and after the closing date for comments, in the

Rules Docket for examination by interested persons. A report that

summarizes each FAA-public contact concerned with the substance of this

AD will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments

submitted in response to this notice must submit a self-addressed,

stamped postcard on which the following statement is made: ``Comments

to Docket Number 98-ANE-07-AD.'' The postcard will be date stamped and

returned to the commenter.

The regulations adopted herein will not have substantial direct

effects on the States, on the relationship between the national

government and the States, or on the distribution of power and

responsibilities among the various levels of government. Therefore, in

accordance with Executive Order 12612, it is determined that this final

rule does not have sufficient federalism implications to warrant the

preparation of a Federalism Assessment.

The FAA has determined that this regulation is an emergency

regulation that must be issued immediately to correct an unsafe

condition in aircraft, and is not a ``significant regulatory action''

under Executive Order 12866. It has been determined further that this

action involves an emergency regulation under DOT Regulatory Policies

and Procedures (44 FR 11034, February 26, 1979). If it is determined

that this emergency regulation otherwise would be significant under DOT

Regulatory Policies and Procedures, a final regulatory evaluation will

be prepared and placed in the Rules Docket. A copy of it, if filed, may

be obtained from the Rules Docket at the location provided under the

caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by

reference, Safety.

Adoption of the Amendment

Accordingly, pursuant to the authority delegated to me by the

Administrator, the Federal Aviation Administration amends part 39 of

the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding the following new

airworthiness directive:

98-19-11 Rolls-Royce Limited, Aero Division-Bristol/S.N.E.C.M.A.:

Amendment 39-10753. Docket 98-ANE-07-AD.

Applicability: Rolls-Royce Limited, (R-R) Aero Division-Bristol/

S.N.E.C.M.A. Olympus 593 Mk. 610-14-28 turbojet engines, installed

on but not limited to British Aerospace/Aerospatiale Concorde series

aircraft.

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.

Compliance: Required as indicated, unless accomplished

previously.

To prevent an exhaust diffuser vane failure, which could result

in an adverse effect on the engine oil and reheat systems, possibly

causing an inflight engine shutdown or damage to the aircraft,

accomplish the following:

(a) Perform initial and repetitive X-ray inspections of exhaust

diffuser vanes for cracks and corrosion, in accordance with R-R/

S.N.E.C.M.A. Service Bulletin (SB) No. OL.593-72-9042-422, Revision

1, dated May 23, 1997, as follows:

(1) Perform the initial inspection at the first module exposure

after accumulating 5,000 hours time since new (TSN).

(2) Thereafter, perform inspections at every module exposure, or

2,000 hours time in service (TIS) since last X-ray inspection,

whichever occurs later.

(3) If an exhaust diffuser vane is found cracked, remove the

exhaust diffuser from service and replace with a serviceable part.

(4) If any evidence of corrosion is found, perform an ultrasonic

inspection for cracks in accordance with paragraph (b) of this AD.

(b) Perform initial and repetitive ultrasonic inspections for

corrosion in the exhaust diffuser vanes in accordance with R-R/

[[Page 49420]]

S.N.E.C.M.A. SB No. OL.593-72-9047-423, dated January 31, 1997, as

follows:

(1) Perform the initial inspection no later than 1,000 hours TIS

since last X-ray inspection in accordance with paragraph (a) of this

AD if no cracks are detected but corrosion is found.

(2) Thereafter, perform inspections at intervals not to exceed

250 hours TIS since last ultrasonic inspection, or 1,000 hours TIS

since an X-ray inspection that discovered no cracks, whichever

occurs later.

(3) If cracking is found, remove the exhaust diffuser from

service and replace with a serviceable part.

(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.

Operators shall submit their requests through an appropriate FAA

Principal Maintenance Inspector, who may add comments and then send

it to the Manager, Engine Certification Office.

Note 2: Information concerning the existence of approved

alternative methods of compliance with this airworthiness directive,

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) to operate the aircraft to a location where

the inspection requirements of this AD can be accomplished.

(e) The actions required by this AD shall be performed in

accordance with the following R-R SBs:

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Document No. Pages revision Date

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OL.593-72-9042-422............ 1-5 1............. May 23, 1997.

Total pages: 5

OL.593-72-9047-423............ 1-7 Original...... January 31, 1997.

Total pages: 7

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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 Rolls-Royce, P.O. Box 3,

Filton, Bristol BS12 7QE, England; telephone 01-17-979-1234, fax 01-

17-979-7575. Copies may be inspected at the FAA, New England Region,

Office of the Regional 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 October 1, 1998.

Issued in Burlington, Massachusetts, on September 8, 1998.

David A. Downey,

Assistant Manager, Engine and Propeller Directorate, Aircraft

Certification Service.

[FR Doc. 98-24643 Filed 9-16-98; 8:45 am]

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