[Federal Register Volume 63, Number 239 (Monday, December 14, 1998)]
[Rules and Regulations]
[Pages 68674-68675]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-32800]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-06-AD; Amendment 39-10940; AD 98-25-14]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce Limited, Bristol Engines 
Division and Rolls-Royce (1971) Limited, Bristol Engines Division Viper 
Series Turbojet Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to Rolls-Royce Limited, Bristol Engines Division and Rolls-
Royce (1971) Limited, Bristol Engines Division, Viper series turbojet 
engines, that requires a one-time visual inspection of the barometric 
flow control unit (BFCU) augmentor and bypass valve joint washer for 
joint washer integrity, and replacement, if necessary, with serviceable 
parts. This amendment is prompted by a report of a high pressure fuel 
leak at the BFCU augmentor and bypass valve assembly joint, washer 
interface. The actions specified by this AD are intended to prevent a 
high pressure fuel leak, which could result in an engine nacelle fire 
and damage to the aircraft.

DATES: Effective February 12, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of February 12, 1999.

ADDRESSES: The service information referenced in this AD may be 
obtained from Rolls-Royce Limited, Bristol Engines Division, Technical 
Publications Department CLS-4, P.O. Box 3, Filton, Bristol, BS34 7QE 
England; telephone 117-979-1234, fax 117-979-7575. This information may 
be examined at the Federal Aviation Administration (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: James Lawrence, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803-5299; telephone (781) 
238-7176, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to Rolls-Royce Limited, Bristol 
Engines Division, (R-R) Viper Mk. 521, 522, 526 and 601 series turbojet 
engines was published in the Federal Register on April 30, 1998 (63 FR 
23688). That action proposed to require a one-time inspection of BFCU 
augmentor and bypass valve joint washer for joint washer integrity, and 
replacement, if necessary, with serviceable parts in accordance with R-
R Alert Service Bulletins (ASBs) Nos. 73-A120, 73-A121, 73-A68, 73-A69, 
73-A35, and 73-A36, dated November 1997.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were received on the 
proposal or the FAA's determination of the cost to the public. The FAA 
has determined that air safety and the public interest require the 
adoption of the rule as proposed.
    There are approximately 140 engines of the affected design in the 
worldwide fleet. The FAA estimates that 52 engines installed on 
aircraft of U.S. registry will be affected by this AD, that it will 
take approximately 5 work hours per engine to accomplish the required 
actions, and that the average labor rate is $60 per work hour. Based on 
these figures, the total cost impact of the AD on U.S. operators is 
estimated to be $15,600.
    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.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and (3) will not have a 
significant economic impact, positive or negative, on a substantial 
number of small entities under the criteria of the Regulatory 
Flexibility Act. A final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it 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:

98-25-14 Rolls-Royce plc: Amendment 39-10940. Docket 98-ANE-06-AD.

    Applicability: Rolls-Royce plc (R-R) Viper Mk. 521, 522, 526 and 
601 series turbojet engines, installed on but not limited to 
Raytheon (formerly British Aerospace, Hawker Siddeley) Models BH.125 
and DH.125 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 (d) of this AD. The request should include an assessment 
of the effect of the modification,

[[Page 68675]]

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 a high pressure fuel leak, which could result in an 
engine nacelle fire and damage to the aircraft, accomplish the 
following:
    (a) For R-R Viper Mk. 521, and 522 series engines, perform a 
one-time inspection of the barometric flow control unit (BFCU) 
augmentor and bypass valve joint washer for joint washer integrity, 
and replace, if necessary, with serviceable parts, in accordance 
with R-R Alert Service Bulletins (ASBs) Nos. 73-A120 and 73-A121, as 
applicable, dated November 1997, as follows:
    (1) For engines with less than 200 hours time in service (TIS) 
since new, overhaul, or repair of the BFCU, inspect within 2 months, 
or 100 hours TIS after the effective date of this AD, whichever 
occurs first.
    (2) For engines with 200 or more hours TIS since new, overhaul, 
or repair of the BFCU, inspect at the next engine removal after the 
effective date of this AD.
    (b) For R-R Viper Mk. 526 series engines, perform a one-time 
inspection of the barometric flow control unit (BFCU) augmentor and 
bypass valve joint washer for joint washer integrity, and replace, 
if necessary, with serviceable parts, in accordance with R-R ASBs 
Nos. 73-A68 and 73-A69, as applicable, dated November 1997, as 
follows:
    (1) For engines with less than 200 hours time in service (TIS) 
since new, overhaul, or repair of the BFCU, inspect within 2 months, 
or 100 hours TIS after the effective date of this AD, whichever 
occurs first.
    (2) For engines with 200 or more hours TIS since new, overhaul, 
or repair of the BFCU, inspect at the next engine removal after the 
effective date of this AD.
    (c) For R-R Viper Mk. 601 series engines, perform a one-time 
inspection of the BFCU augmentor and bypass valve joint washer for 
joint washer integrity, and replace, if necessary, with serviceable 
parts, in accordance with R-R ASBs Nos. 73-A35 and 73-A36, as 
applicable, dated November 1997, as follows:
    (1) For engines with less than 200 hours TIS since new, 
overhaul, or repair of the BFCU, inspect within 2 months, or 100 
hours TIS after the effective date of this AD, whichever occurs 
first.
    (2) For engines with 200 or more hours TIS since new, overhaul, 
or repair of the BFCU, inspect at the next engine removal after the 
effective date of this AD.
    (d) 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.
    (e) 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 requirements of this AD can be accomplished.
    (f) The actions required by this AD shall be done in accordance 
with the following R-R ASBs:

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             Document No.                Pages             Date
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73-A35................................      1-6  Nov. 1997.
  Total Pages: 6.
73-A36................................      1-6  Nov. 1997.
  Total Pages: 6.
73-A68................................      1-6  Nov. 1997.
  Total Pages: 6.
73-A69................................      1-6  Nov. 1997.
  Total Pages: 6.
73-A120...............................      1-6  Nov. 1997.
  Total Pages: 6.
73-A121...............................      1-6  Nov. 1997.
  Total Pages: 6.
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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 Limited, Bristol 
Engines Division, Technical Publications Department CLS-4, P.O. Box 
3, Filton, Bristol, BS34 7QE England; telephone 117-979-1234, fax 
117-979-7575. 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.
    (g) This amendment becomes effective on February 12, 1999.

    Issued in Burlington, Massachusetts, on November 30, 1998.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 98-32800 Filed 12-11-98; 8:45 am]
BILLING CODE 4910-13-U