[Federal Register Volume 67, Number 39 (Wednesday, February 27, 2002)]
[Proposed Rules]
[Pages 8910-8912]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-4587]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NE-35-AD]
RIN 2120-AA64


Airworthiness Directives; MT-Propeller Entwicklung GMBH Models 
MTV-9-B-C and MTV-3-B-C Propellers

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The Federal Aviation Administration (FAA) proposes to 
supersede an existing airworthiness directive (AD), applicable to MT-
Propeller Entwicklung GMBH models MTV-9-B-C and MTV-3-B-C propellers. 
That AD currently requires initial and repetitive inspections of Torx 
head blade root lag screws that are used on certain serial number (SN) 
propellers and replacing all lag screws on the propeller if any screws 
are found broken or with insufficient torque. In addition, that AD 
currently requires replacing certain part number (P/N) Torx head blade 
root lag screws with improved, hexagonal head blade root lag screws. 
This proposal would require the expansion of the applicability from 
certain SN propellers to all propellers with certain SN blades that may 
contain the suspect Torx head blade root lag screws. This proposal is 
prompted by FAA awareness that a propeller hub of an affected propeller 
could be changed, thereby changing the propeller serial number, 
creating a propeller that is not listed in the AD and that has affected 
blades and lag screws. The actions specified by the proposed AD are 
intended to prevent failure of the blade root lag screw, which could 
result in propeller blade separation and loss of control of the 
airplane.

DATES: Comments must be received by April 29, 2002.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 99-NE-35-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may be inspected at 
this location, by appointment, between 8 a.m. and 4:30 p.m., Monday 
through Friday, except Federal holidays. Comments may also be sent via 
the Internet using the following address: ``[email protected]''. 
Comments sent via the Internet must contain the docket number in the 
subject line.
    The service information referenced in the proposed rule may be 
obtained from MT-Propeller Entwicklung GMBH, Airport Straubing-
Wallmuhle, D-94348 Atting, Germany; telephone (0 94 29) 84 33, fax (0 
94 29) 84 32, Internet address: ``[email protected]''. This information 
may be examined, by appointment, at the FAA, New England Region, Office 
of the Regional Counsel, 12 New England Executive Park, Burlington, MA.

FOR FURTHER INFORMATION CONTACT: Wayne E. Gaulzetti, Aerospace 
Engineer, Boston Aircraft Certification Office, FAA, Engine and 
Propeller Directorate, 12 New England Executive Park, Burlington, MA 
01803-5299; telephone (781) 238-7156, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed 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 above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this action may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of

[[Page 8911]]

the proposed 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 summarizing each FAA-public 
contact concerned with the substance of this proposal will be filed in 
the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 99-NE-35-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRM's

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, New England Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 99-NE-35-AD, 12 New England Executive Park, 
Burlington, MA 01803-5299.

Discussion

    On June 23, 1999, the Federal Aviation Administration (FAA) issued 
airworthiness directive (AD) 99-14-06, Amendment 39-11216 (64 FR 36777, 
July 8, 1999), to require for certain serial number propellers, initial 
and repetitive inspections of Torx head blade root lag screws for 
torque values and breakage, and, if any screws are found broken or with 
insufficient torque, replacement of all screws with new lag screws. In 
addition, that AD requires replacement of certain model Torx head blade 
root lag screws with improved, hexagonal head blade root lag screws.
    Since AD 99-14-06 was issued, a question from a repair facility to 
the FAA brought to light that if a propeller hub of an affected 
propeller were to be replaced, the propeller serial number would then 
be different and, not necessarily on the list of affected propellers in 
the AD. This would cause affected blades to be missed for inspections. 
To eliminate this potential for blades not being inspected, this 
proposal would require the same inspections as AD 99-14-06 but for all 
model MTV-9-B-C propellers equipped with CL250-27, or CL260-27 blades 
with S/N's starting with letter ``A'' through ``P'' and all model MTV-
3-B-C propellers equipped with S/N L250-21 blades with S/N's starting 
with letter ``A'' through ``P''.

Manufacturer's Service Information

    MT-Propeller Entwicklung GMBH has issued Service Bulletin (SB) No. 
17-A, dated March 5, 1999, that specifies procedures for inspections 
for Torx head blade root lag screws for torque values and breakage, and 
replacement of Torx head blade root lag screws, P/N A-550-85 (4mm 
thread pitch), with improved, hexagonal head blade root lag screws, P/N 
A-983-85. The LBA classified this SB as mandatory and issued 
airworthiness directives (AD's) 1999-081/2 and 1999-082/2 in order to 
assure the airworthiness of these propellers in Germany.

Bilateral Agreement Information

    This propeller model is manufactured in Germany 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 LBA has kept the FAA informed of 
the situation described above. The FAA has examined the findings of the 
LBA, 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.

Proposed Requirements of this AD

    Since an unsafe condition has been identified that is likely to 
exist or develop on other propellers of the same type design registered 
in the United States, this proposal requires initial and repetitive 
inspections of Torx head blade root lag screws for torque values and 
breakage, and, if any screws are found with insufficient torque or are 
broken, replacement of all screws with new lag screws. In addition, 
this AD requires replacement of Torx head blade root lag screws, P/N A-
550-85 (4mm thread pitch), with improved, hexagonal head blade root lag 
screws, P/N A-983-85. The actions would be required to be done in 
accordance with the SB described previously.

Economic Analysis

    There are approximately 250 propellers of the affected design in 
the worldwide fleet. The FAA estimates that 125 propellers installed on 
airplanes of U.S. registry would be affected by this proposed AD. The 
FAA also estimates that it would take approximately 13 work hours per 
propeller to do the proposed actions, and that the average labor rate 
is $60 per work hour. Based on these figures, the total cost of the 
proposed AD on U.S. operators is estimated to be $97,500.

Regulatory Analysis

    This proposed rule does not have federalism implications, as 
defined in Executive Order 13132, because it would not have a 
substantial direct effect 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. 
Accordingly, the FAA has not consulted with state authorities prior to 
publication of this proposed rule.
    For the reasons discussed above, I certify that this proposed 
regulation (1) is not a ``significant regulatory action'' under 
Executive Order 12866; (2) is not a ``significant rule'' under the DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) if promulgated, will not have a significant economic effect, 
positive or negative, on a substantial number of small entities under 
the criteria of the Regulatory Flexibility Act. A copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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 39-11216, (64 FR 
36777 July 8, 1999), and by adding a new airworthiness directive:

MT-Propeller Entwicklung GMBH: Docket No. 99-NE-35-AD. Supersedes AD 
99-14-06, Amendment 39-11216.

    Applicability: This airworthiness directive (AD) is applicable 
to MT-Propeller Entwicklung GMBH Model MTV-9-B-C propellers equipped 
with CL250-27 or CL260-27 blades with serial numbers (SN's) starting 
with letter ``A'' through ``P'', equipped with Torx head blade root 
lag screws, part number (P/N) A-549-85 (3mm thread pitch), or P/N A-
550-85 (4mm thread pitch); and Model MTV-3-B-C propellers, equipped 
with L250-21 blades with SN's starting with letter ``A'' through 
``P'', equipped with Torx head blade root lag screws, P/N A-549-85 
(3mm thread pitch),

[[Page 8912]]

or P/N A-550-85 (4mm thread pitch). These propellers are installed 
on, but not limited to, Sukhoi SU-26, SU-29, SU-31; Yakovlev YAK-52, 
YAK-54, YAK-55, and Technoavia SM-92 airplanes.

    Note 1: This airworthiness directive (AD) applies to each 
propeller 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 propellers 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, 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 already done.
    To prevent blade root lag screw breakage, which could result in 
propeller blade separation and loss of control of the airplane, do 
the following:
    (a) For propellers with Torx head blade root lag screws, P/N A-
549-85 (3mm thread pitch), inspect Torx head blade root lag screws 
for torque values and breakage in accordance with MT-Propeller 
Entwicklung GMBH Service Bulletin (SB) No. 17-A, dated March 5,1999, 
as follows:
    (1) Initially inspect within 50 hours time-in-service (TIS), or 
within two months after the effective date of this AD, whichever 
occurs first.
    (2) Thereafter, inspect at intervals not to exceed 100 hours 
TIS, or within 12 months, whichever occurs first.
    (3) Before further flight, if any lag screws are found broken or 
with torque less than 64 foot-pounds, replace all lag screws with 
new lag screws.
    (b) For propellers with lag screws, P/N A-550-85 (4mm thread 
pitch), inspect lag screws for torque values and breakage in 
accordance with MT-Propeller Entwicklung GMBH SB No. 17-A, dated 
March 5,1999, as follows:
    (1) Inspect within 50 hours TIS, or within two months after the 
effective date of this AD, whichever occurs first.
    (2) Before further flight, if any lag screws are found broken or 
with torque less than 64 foot-pounds, replace all lag screws with 
improved, hexagonal head blade root lag screws, P/N A-983-85. Torque 
screws to 58-60 foot-pounds.
    (c) Replace lag screws, P/N A-550-85, within 100 hours TIS, or 
within 12 months after the effective date of this AD, with lag 
screws, P/N A-983-85, in accordance with MT-Propeller Entwicklung 
GMBH SB No. 17-A, dated March 5, 1999. Torque screws to 58-60 foot-
pounds.

Alternative Methods of Compliance

    (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, Boston Aircraft Certification 
Office. Operators must submit their requests through an appropriate 
FAA Maintenance Inspector, who may add comments and then send it to 
the Manager, Boston Aircraft 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 Boston Aircraft Certification 
Office.

Special Flight Permits

    (e) Special flight permits may be issued in accordance 
Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 
21.197 and 21.199) to operate the airplane to a location where the 
requirements of this AD can be done.

    Issued in Burlington, Massachusetts, on February 20, 2002.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 02-4587 Filed 2-26-02; 8:45 am]
BILLING CODE 4910-13-U