
[Federal Register: May 23, 2008 (Volume 73, Number 101)]
[Proposed Rules]               
[Page 30007-30009]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr23my08-14]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0585; Directorate Identifier 2008-NM-027-AD]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 747SP Series Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for all 
Boeing Model 747SP series airplanes. This proposed AD would require 
repetitive lubrication of the rudder tab hinges and repetitive 
replacement of the rudder tab control rods. This proposed AD results 
from reports of freeplay-induced vibration of the control surfaces on 
Boeing Model 727, 737, 757, and 767 airplanes. We are proposing this AD 
to prevent damage to the control surface structure during flight, which 
could result in loss of control of the airplane.

DATES: We must receive comments on this proposed AD by July 7, 2008.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://
www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this AD, contact Boeing 
Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (telephone 800-647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Kathleen Arrigotti, Aerospace 
Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-
3356; telephone (425) 917-6426; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2008-0585; 
Directorate Identifier 2008-NM-027-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://
www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We have received reports of freeplay-induced vibration of control 
surfaces on Boeing Model 727, 737, 757, and 767 airplanes. Excessive 
wear of components or interfaces allows excessive freeplay of the 
control surfaces and can cause unacceptable airframe vibration during 
flight. The potential for vibration of the control surface should be 
avoided because the point of transition from vibration to divergent 
flutter is unknown. Divergent flutter can cause damage to the control 
surface structure during flight. This condition, if not corrected, 
could result in loss of control of the airplane.
    Although there have been no reports of freeplay-induced vibration 
of the rudder tabs for Model 747SP airplanes, the affected control 
surfaces on Boeing Model 727, 737, 757, and 767 airplanes and Boeing 
Model 747SP airplanes are similar in design. Therefore, all of these 
models might be subject to the identified unsafe condition.

Relevant Service Information

    We have reviewed Boeing Special Attention Service Bulletin 747-27-
2447, dated January 17, 2008. The service bulletin describes procedures 
for repetitive lubrication of the rudder tab

[[Page 30008]]

hinges, and repetitive replacement of the rudder tab control rods. For 
airplanes on which BMS 3-33 grease is used to lubricate the rudder tab 
hinges, the compliance time for the first lubrication is within 9 
months after the date on the service bulletin, and the repetitive 
interval is not to exceed 18 months thereafter. For airplanes on which 
BMS 3-33 grease is not used to lubricate the rudder tab hinges, the 
compliance time for the first lubrication is 9 months after the date on 
the service bulletin, and the repetitive interval is not to exceed 9 
months thereafter. The compliance time for all airplanes for the first 
replacement of the rudder tab control rods is within 6,000 flight hours 
after the date on the service bulletin, and the repetitive interval is 
not to exceed 8,000 flight hours thereafter.

Other Relevant Rulemaking

    The following ADs resulted from reports of freeplay-induced 
vibration of control surfaces on Boeing Model 727, 737, 757, and 767 
airplanes.
    On March 30, 2006, we issued AD 2006-07-23 (amendment 39-14550, 71 
FR 18194, April 11, 2006) for all Boeing Model 757 airplanes. That AD 
requires repetitive measurements of the freeplay of each of the three 
power control units that move the rudder; repetitive lubrication of 
rudder components; and corrective actions if necessary. That AD 
resulted from a report of freeplay-induced vibration of the rudder. 
That AD explained that the potential for vibration of the control 
surface should be avoided because the point of transition from 
vibration to divergent flutter is unknown. We issued that AD to prevent 
excessive vibration of the airframe during flight, which could result 
in divergent flutter and loss of control of the airplane.
    On June 15, 2006, we issued AD 2006-13-16 (amendment 39-14669, 71 
FR 36481, June 27, 2006) for certain Boeing Model 727 airplanes. That 
AD requires repetitive measurements of the freeplay of the left and 
right outboard aileron balance tabs and of the upper and lower rudder 
tabs, and related investigative/corrective actions if necessary. That 
AD also requires repetitive lubrication of the hinge bearings and rod 
end bearings of the outboard aileron balance tabs. That AD resulted 
from reports of freeplay-induced vibration of the outboard aileron 
balance tabs and rudder tabs. We issued that AD to prevent excessive 
vibration of the airframe during flight, which could result in 
divergent flutter and loss of control of the airplane.
    On September 28, 2006, we issued AD 2006-21-01 (amendment 39-14784, 
71 FR 59368, October 10, 2006) for all Boeing Model 737 airplanes. That 
AD requires repetitive measurement of the freeplay of both aileron 
balance tabs; repetitive lubrication of the aileron balance tab hinge 
bearings and rod end bearings; and related investigative and corrective 
actions if necessary. That AD resulted from reports of freeplay-induced 
vibration of the aileron balance tab. That AD also explained that the 
potential for vibration of the control surface should be avoided 
because the point of transition from vibration to divergent flutter is 
unknown. We issued that AD to prevent excessive vibration of the 
airframe during flight, which could result in loss of control of the 
airplane.
    On November 16, 2007, we issued AD 2007-24-08 (amendment 39-15274, 
72 FR 67236, November 28, 2007), for all Boeing Model 767 airplanes. 
That AD requires repetitive measurements of the rudder freeplay and the 
elevator freeplay for each of the power control actuators that move the 
rudder and elevator, corrective and related investigative actions if 
necessary, and repetitive lubrications of the rudder and elevator 
components. For some airplanes, that AD also requires related 
concurrent actions. That AD also explained that the potential for 
vibration of the control surface should be avoided because the point of 
transition from vibration to divergent flutter is unknown. We issued 
that AD to prevent excessive vibration of the airframe during flight, 
which could result in loss of control of the airplane.

FAA's Determination and Requirements of This Proposed AD

    We are proposing this AD because we evaluated all relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the(se) same type 
design(s). This proposed AD would require accomplishing the actions 
specified in the service information described previously.

Costs of Compliance

    We estimate that this proposed AD would affect 7 airplanes of U.S. 
registry. The following table provides the estimated costs for U.S. 
operators to comply with this proposed AD. The average labor rate is 
$80 per work hour.

                                                 Estimated Costs
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                                      Work
              Action                 hours           Parts             Cost per product          Fleet cost
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Lubrication.......................        2  None.................  $160, per cycle......  $1,120, per cycle.
Replacement.......................       16  $39,511..............  $40,791, per cycle...  $285,537, per cycle.
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Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. ``Subtitle VII: Aviation Programs'' 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
``Subtitle VII, Part A, Subpart III, Section 44701: General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD 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.
    For the reasons discussed above, I certify 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. Will not have a significant economic impact, positive or 
negative,

[[Page 30009]]

on a substantial number of small entities under the criteria of the 
Regulatory Flexibility Act.
    You can find our regulatory evaluation and the estimated costs of 
compliance in the AD Docket.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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. The FAA amends Sec.  39.13 by adding the following new AD:

Boeing: Docket No. FAA-2008-0585; Directorate Identifier 2008-NM-
027-AD.

Comments Due Date

    (a) We must receive comments by July 7, 2008.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to all Boeing Model 747SP series airplanes.

Unsafe Condition

    (d) This AD results from reports of freeplay-induced vibration 
of the control surfaces on Boeing Model 727, 737, 757, and 767 
airplanes. We are issuing this AD to prevent damage to the control 
surface structure during flight, which could result in loss of 
control of the airplane.

Compliance

    (e) Comply with this AD within the compliance times specified, 
unless already done.

Repetitive Lubrication and Replacement

    (f) At the applicable compliance time listed in Paragraph 1.E., 
``Compliance,'' of Boeing Special Attention Service Bulletin 747-27-
2447, dated January 17, 2008, lubricate the rudder tab hinges and 
replace the rudder tab control rods with new control rods. Repeat 
the lubrication and replacement thereafter at the applicable repeat 
interval listed in paragraph 1.E., ``Compliance,'' of the service 
bulletin. Do all actions in accordance with the Accomplishment 
Instructions of Boeing Special Attention Service Bulletin 747-27-
2447, dated January 17, 2008. Where Boeing Special Attention Service 
Bulletin 747-27-2447, dated January 17, 2008, specifies a compliance 
time after the date on the service bulletin, this AD requires 
compliance within the specified compliance time after the effective 
date of this AD.

Alternative Methods of Compliance (AMOCs)

    (g)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
FAA, ATTN: Kathleen Arrigotti, Aerospace Engineer, Airframe Branch, 
ANM-120S, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; 
telephone (425) 917-6426; fax (425) 917-6590; has the authority to 
approve AMOCs for this AD, if requested using the procedures found 
in 14 CFR 39.19.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your appropriate principal inspector (PI) in the FAA 
Flight Standards District Office (FSDO), or lacking a PI, your local 
FSDO.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD, if it is approved by an 
Authorized Representative for the Boeing Commercial Airplanes 
Delegation Option Authorization Organization who has been authorized 
by the Manager, Seattle ACO, to make those findings. For a repair 
method to be approved, the repair must meet the certification basis 
of the airplane, and the approval must specifically refer to this 
AD.

    Issued in Renton, Washington, on May 8, 2008.
Michael J. Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E8-11567 Filed 5-22-08; 8:45 am]

BILLING CODE 4910-13-P
