[Federal Register Volume 63, Number 31 (Tuesday, February 17, 1998)]
[Rules and Regulations]
[Pages 7646-7648]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-3516]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-ANE-43; Amendment 39-10325; AD 98-04-13]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce Limited Dart Series 
Turboprop Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD), applicable to Rolls-Royce Limited (R-R) Dart series turboprop 
engines, that currently establishes a life limit for propeller low 
torque switches. This amendment adds two propeller low torque switch 
part numbers and two R-R Dart engine models that were omitted from the 
current AD, and establishes a calendar end-date for removal of 
propeller low torque switches from service. This amendment is prompted 
by the need to add omitted part numbers and engine models to the AD. 
The actions specified by this AD are intended to prevent cracking of 
the snap diaphragm in the propeller low torque switch, which could 
delay propeller auto-feathering and thereby adversely affect aircraft 
controllability.

DATES: Effective March 24, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of March 24, 1998.

ADDRESSES: The service information referenced in this AD may be 
obtained from Rolls-Royce plc, Attn: Dart Engine Service Manager, East 
Kilbride, Glasgow G74 4PY, Scotland. This information may be examined 
at the Federal Aviation Administration (FAA), New England Region, 
Office of the Assistant Chief Counsel, 12 New England Executive Park, 
Burlington, MA 01803-5299; 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: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) by superseding Airworthiness 
Directive (AD) 90-08-12, Amendment 39-6473 (55 FR 12477, April 4, 
1990), which is applicable to Rolls-Royce Limited (R-R) Dart series 
turboprop engines, was published in the Federal Register on October 2, 
1995 (60 FR 51377). That action proposed to add two propeller low 
torque switch part numbers and two R-R Dart engine models that were 
omitted from AD 90-08-12. In addition, the proposed AD establishes 30 
days after the effective date of the AD as a calendar end-date for 
removal of propeller low torque switches.
    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 
manufacturer has confirmed that since the issuance of the NPRM, all 
affected engines have had the low torque switch removed. Therefore, 
there are no affected engines installed on aircraft of U.S. registry 
and further opportunity for comment is unnecessary.
    The FAA has made some changes to the applicability paragraph of 
this AD to reflect the lack of affected engines installed on aircraft 
of U.S. registry and changes from Mk. to Mk. series.
    There are approximately 2,880 engines of the affected design in the 
worldwide fleet. The FAA estimates that

[[Page 7647]]

450 engines installed on aircraft of U.S. registry will be affected by 
this AD, that it will take approximately 1.5 work hours per engine to 
accomplish the required actions, and that the average labor rate is $60 
per work hour. Required parts will cost approximately $3,800 per 
engine. Based on these figures, the total cost impact of the AD on U.S. 
operators is estimated to be $1,750,500.
    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 removing Amendment 39-6473 (55 FR 
12477, April 4, 1990) and by adding a new airworthiness directive, 
Amendment 39-10325, to read as follows:

98-04-13  Rolls-Royce Limited: Amendment 39-10325. Docket 94-ANE-43. 
Supersedes AD 90-08-12, Amendment 39-6473.

    Applicability: Rolls-Royce Limited (R-R) Dart Mk. 506, 10, 511 
series, 514 series, 525 series, 526, 527, 528 series, 529 series, 
530, 531, 532 series, 535 series, 542 series, 551 series, and 552 
series turboprop engines, installed on but not limited to the 
following aircraft: Gulfstream Aerospace Corp. G-159, British 
Aerospace HS 748, Fokker Aircraft F.27, Mitsubishi Heavy Industries 
YS-11, General Dynamics (Convair) 580 and 600 series, and Vickers 
Armstrongs (Aircraft Limited) Viscount.

    Note 1: Rolls-Royce Limited engine models Mk. 515, 520, 533, 
534, 536, and 543 were removed in this final rule from the NPRM as 
these engine models were not U.S.-validated.

    Note 2: Other changes to the final rule's applicability from the 
NPRM's applicability are as follows:

Mk. 511 was changed to Mk. 511 series
Mk. 514 was changed to Mk. 514 series
Mk. 525 was changed to Mk. 525 series
Mk. 528 was changed to Mk. 528 series
Mk. 529 was changed to Mk. 529 series
Mk. 532 was changed to Mk. 532 series
Mk. 535 was changed to Mk. 535 series
Mk. 542 was changed to Mk. 542 series
Mk. 551 was changed to Mk. 551 series
Mk. 552 was changed to Mk. 552 series.

    Note 3: 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 (f) 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 cracking of the snap diaphragm in the propeller low 
torque switch, which could delay propeller auto-feathering and 
thereby adversely affect aircraft controllability, remove from 
service propeller low torque switch part numbers (P/N) 3700892, 
3700895, 3701232, 3500355, 3500356, 3500410 through 3500412, L944707 
through L944709, L944738 through L944740, L944742 through L944744, 
L944769, L944772, and L944774, in accordance with R-R Dart Aero 
Engine Service Bulletin (SB) No. Da61-12, Revision 2, dated 
September 1978, as follows:
    (a) Remove from service propeller low torque switches that have 
accumulated 5 or more calendar years time in service (TIS) on the 
effective date of this AD, within 30 days after the effective date 
of this AD, and replace with a serviceable part.
    (b) Remove from service propeller low torque switches that have 
accumulated less than 5 calendar years TIS on the effective date of 
this AD, within 5 calendar years total TIS, or within 30 days after 
the effective date of this AD, whichever occurs later, and replace 
with a serviceable part.
    (c) Remove from service propeller low torque switches that 
cannot have their in-service calendar time established within 30 
days after the effective date of this AD, and replace with a 
serviceable part.
    (d) Thereafter, remove from service new or overhauled propeller 
low torque switches at or prior to accumulating 5 calendar years TIS 
since initial installation on an engine. This limit includes storage 
or on-shelf time accumulated after initial installation on an 
engine. Overhaul of the propeller low torque switch zero-times the 
part.
    (e) For the purpose of this AD, a serviceable part is defined as 
a new or overhauled propeller low torque switch with less than 5 
calendar years TIS since first entry into service.
    (f) 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 4: Information concerning the existence of approved 
alternative method of compliance with this AD, if any, may be 
obtained from the Engine Certification Office.

    (g) 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.
    (h) The actions required by this AD shall be done in accordance 
with the following R-R SB:

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               Document No.                  Pages            Revision                        Date              
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Dart Aero Engine SB:                                                                                            
  No. Da61-12............................       1-4  2........................  September 1978.                 
                                                5-6  Original.................  May 1976.                       
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[[Page 7648]]

    Total pages: 6.
    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 plc, Attn: Dart 
Engine Service Manager, 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.
    (i) This amendment becomes effective on March 24, 1998.

    Issued in Burlington, Massachusetts, on February 4, 1998.
James C. Jones,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 98-3516 Filed 2-13-98; 8:45 am]
BILLING CODE 4910-13-U