7-6, conversion from vibration to divergent flutter

[Federal Register: September 20, 2007 (Volume 72, Number 182)]
[Proposed Rules]
[Page 53701-53704]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr20se07-16]

-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-29259; Directorate Identifier 2007-NM-195-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 767 Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to supersede an existing airworthiness
directive (AD) that applies to all Boeing Model 767 airplanes. The
existing AD currently requires repetitive measurements of the rudder
and elevator freeplay, repetitive lubrications of rudder and elevator
components, and related investigative/corrective actions if necessary.
This proposed AD would instead require revised repetitive measurements
of the rudder freeplay and the elevator freeplay for each of the power
control actuators (PCAs) 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,
this proposed AD would also require related concurrent actions. This
proposed AD results from reports of freeplay-induced vibration of the
rudder and the elevator. The potential for vibration of the control
surface should be avoided because the point of transition from
vibration to divergent flutter is unknown. We are proposing this AD to
prevent excessive vibration of the airframe during flight, which could
result in loss of control of the airplane.

DATES: We must receive comments on this proposed AD by October 22,
2007.

ADDRESSES: Use one of the following addresses to submit comments on
this proposed AD.
DOT Docket Web site: Go to http://dms.dot.gov and follow

the instructions for sending your comments electronically.
Government-wide rulemaking Web site: Go to http://www.regulations.gov
and follow the instructions for sending your

comments electronically.
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.
Fax: (202) 493-2251.
Hand Delivery: Room W12-140 on the ground floor of the
West Building, 1200 New Jersey Avenue, SE., Washington, DC, between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle,
Washington 98124-2207, for service information identified in this
proposed AD.

FOR FURTHER INFORMATION CONTACT: Tamara Anderson, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425)
917-6421; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any relevant written data, views, or
arguments regarding this proposed AD. Send your comments to an address
listed in the ADDRESSES section. Include the docket number ``Docket No.
FAA-2007-29259; Directorate Identifier 2007-NM-195-AD'' at the
beginning of your comments. We specifically invite comments on the
overall regulatory, economic, environmental, and energy aspects of the
proposed AD. We will consider all comments received by the closing date
and may amend the proposed AD in light of those comments.
We will post all comments we receive, without change, to http://dms.dot.gov
, including any personal information you provide. We will

also post a report summarizing each substantive verbal contact with FAA
personnel concerning this proposed AD. Using the search function of
that Web site, anyone can find and read the comments in any of our
dockets, including the name of the individual who sent the comment (or
signed the comment on behalf of an association, business, labor union,
etc.). You may review the DOT's complete Privacy Act Statement in the
Federal Register published on April 11, 2000 (65 FR 19477-78), or may
can visit http://dms.dot.gov.


Examining the Docket

You may examine the AD docket on the Internet at http://dms.dot.gov
, or in person at the Docket Operations office between 9

a.m. and 5 p.m., Monday through Friday, except Federal holidays. The
Docket Operations office (telephone (800) 647-5527) is located on the
ground level of the West Building at the DOT street address stated in
the ADDRESSES section. Comments will be available in the AD docket
shortly after

[[Page 53702]]

the Docket Management System receives them.

Discussion

On May 17, 2006, we issued AD 2006-11-12, amendment 39-14616 (71 FR
30272, May 26, 2006), for all Boeing Model 767 airplanes. That AD
requires repetitive measurements of the rudder and elevator freeplay,
repetitive lubrication of rudder and elevator components, and related
investigative/corrective actions if necessary. That AD resulted from
reports of freeplay-induced vibration of the rudder and the elevator.
We issued that AD to prevent excessive vibration of the airframe during
flight, which could result in loss of control of the airplane.

Actions Since Existing AD Was Issued

Since we issued AD 2006-11-12, we have learned that the procedures
in Boeing Special Attention Service Bulletins 767-27-0197 and 767-27-
0198, both dated October 27, 2005 (referred to in the existing AD as
the appropriate sources of service information for accomplishing the
actions required by that AD), yielded false-positive results for the
measurements of the rudder and elevator freeplay. The service bulletin
instructions for measuring the freeplay also did not include
information on certain prior or concurrent actions to be performed on
certain airplanes. Therefore, we have determined that the requirements
of AD 2006-11-12 do not adequately address the identified unsafe
condition.

Other Relevant Rulemaking

On February 21, 2001, we issued AD 2001-04-09, amendment 39-12128
(66 FR 13227, March 5, 2001). That AD requires repetitively testing the
elevator control system to determine if an elevator power control
actuator (PCA) is rigged incorrectly due to yielded or failed shear
rivets in a bellcrank assembly, and follow-on actions, if necessary.
That AD refers to Boeing Alert Service Bulletins 767-27A0168 and 767-
27A0169, both dated November 21, 2000, as the applicable sources of
service information. Boeing Alert Service Bulletins 767-27A0168 and
767-27A0169 are referred to in this proposed AD as sources of service
information for accomplishing concurrent actions on certain airplanes.
This proposed AD would not affect any of the requirements of AD 2001-
04-09.

Relevant Service Information

We have reviewed Boeing Special Attention Service Bulletins 767-27-
0197, Revision 1, dated July 19, 2007 (for Model 767-200, -300, and -
300F series airplanes); and 767-27-0198, Revision 1, dated July 19,
2007 (for Model 767-400ER series airplanes). The service bulletins
describe improved procedures for repetitive measurements of the rudder
freeplay and the elevator freeplay for each of the PCAs that move the
rudder and elevator. For freeplay that exceeds certain specified
limits, the service bulletins describe procedures for doing applicable
related corrective and related investigative actions. Corrective and
related investigative actions include repairing or replacing all
applicable affected parts if necessary, and repeating the freeplay
measurement, until the freeplay is within acceptable limits. Affected
parts may include worn or loose hanger links, reaction links, PCA rod
ends, and trunnion connections that contribute to the freeplay. The
service bulletins also describe procedures and repetitive intervals for
repetitive lubrication of the rudder and elevator components that are
the same as those described in the original issues of the service
bulletins.
For certain Model 767-200, -300, and -300F series airplanes, Boeing
Special Attention Service Bulletin 767-27-0197, Revision 1, specifies
prior or concurrent accomplishment of Boeing Alert Service Bulletin
767-27A0168, dated November 21, 2000, which describes, among other
actions, procedures for inspecting the elevator bellcranks for any
shear rivets that are broken or yielded.
For certain Model 767-400ER series airplanes, Boeing Special
Attention Service Bulletin 767-27-0198, Revision 1, specifies prior or
concurrent accomplishment of Boeing Alert Service Bulletin 767-27A0169,
dated November 21, 2000, which describes, among other actions,
procedures for inspecting the elevator bellcranks for any shear rivets
that are broken or yielded.
Accomplishing the actions specified in the service information is
intended to adequately address the unsafe condition.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an
unsafe condition that is likely to develop on other airplanes of the
same type design. For this reason, we are proposing this AD, which
would supersede AD 2006-11-12. This proposed AD would require
accomplishing the actions specified in the special attention service
bulletins described previously, except as discussed under ``Differences
Between the Proposed AD and the Special Attention Service Bulletins.''

Differences Between the Proposed AD and the Special Attention Service
Bulletins

Although Revision 1 of Boeing Special Attention Service Bulletins
767-27-0197 and 767-27-0198 recommends accomplishing the initial rudder
and elevator freeplay measurements within 18 months after the date on
the service bulletins, the proposed AD would require a compliance time
of 12 months after the effective date of the AD. We have determined
that 18 months would not address the identified unsafe condition soon
enough to ensure an adequate level of safety for the affected fleet. In
developing an appropriate compliance time for this proposed AD, we
considered the degree of urgency associated with the subject unsafe
condition, and the possibility that this proposed AD could extend the
compliance time for airplanes on which the measurements required in AD
2006-11-12 have not been accomplished. In light of these factors, we
find that 12 months represents an appropriate interval of time for
affected airplanes to continue to operate without compromising safety.
This difference has been coordinated with Boeing.

Costs of Compliance

There are about 979 airplanes of the affected design in the
worldwide fleet. The following table provides the estimated costs for
U.S. operators to comply with this proposed AD. No parts are necessary
to accomplish any action.

Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
Number of U.S.-
Action Work hours Average labor Cost per airplane registered Fleet cost
rate per hour airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Freeplay measurement..................... 30 $80 $2,400, per measurement 423 $1,015,200, per measurement
cycle. cycle.

[[Page 53703]]


Lubrication.............................. 27 $80 $2,160, per lubrication 423 $913,680, per lubrication
cycle. cycle.
--------------------------------------------------------------------------------------------------------------------------------------------------------

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 have 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 that the 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, on a substantial number of small entities under the criteria
of the Regulatory Flexibility Act.
We prepared a regulatory evaluation of the estimated costs to
comply with this proposed AD and placed it in the AD docket. See the
ADDRESSES section for a location to examine the regulatory evaluation.

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 Federal Aviation Administration (FAA) amends Sec. 39.13 by
removing amendment 39-14616 (71 FR 30272, May 26, 2006) and adding the
following new airworthiness directive (AD):

Boeing: Docket No. FAA-2007-29259; Directorate Identifier 2007-NM-
195-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by October
22, 2007.

Affected ADs

(b) This AD supersedes AD 2006-11-12.

Applicability

(c) This AD applies to all Boeing Model 767-200, -300, -300F,
and -400ER series airplanes, certificated in any category.

Unsafe Condition

(d) This AD results from reports of freeplay-induced vibration
of the rudder and the elevator. The potential for vibration of the
control surface should be avoided because the point of transition
from vibration to divergent flutter is unknown. We are issuing this
AD to prevent excessive vibration of the airframe during flight,
which could result in loss of control of the airplane.

Compliance

(e) You are responsible for having the actions required by this
AD performed within the compliance times specified, unless the
actions have already been done.

Service Bulletin References

(f) The term ``service bulletin,'' as used in this AD, means the
Accomplishment Instructions and Appendices A, B, and C of the
following service bulletins, as applicable:
(1) For Model 767-200, -300, and -300F series airplanes: Boeing
Special Attention Service Bulletin 767-27-0197, Revision 1, dated
July 19, 2007; and
(2) For Model 767-400ER series airplanes: Boeing Special
Attention Service Bulletin 767-27-0198, Revision 1, dated July 19,
2007.

Repetitive Measurements

(g) At the latest of the compliance times specified in
paragraphs (g)(1), (g)(2), and (g)(3) of this AD, as applicable:
Measure the rudder and elevator freeplay. Repeat the measurement
thereafter at intervals not to exceed 12,000 flight hours or 36
months, whichever occurs first. Do all actions required by this
paragraph in accordance with the service bulletin.
(1) Within 12 months after the effective date of this AD.
(2) Within 36 months since the date of issuance of the original
standard airworthiness certificate or the date of issuance of the
original export certificate of airworthiness.
(3) For the elevator freeplay measurement: Within 12,000 flight
hours or within 36 months after the last elevator freeplay
inspection accomplished in accordance with Boeing Special Attention
Service Bulletin 767-27-0197 or 767-27-0198, both dated October 27,
2005, as applicable, whichever occurs first.

Related Investigative and Corrective Actions

(h) If any measurement found during the measurement required by
paragraph (g) of this AD exceeds any applicable limit specified in
the service bulletin: Before further flight, do the applicable
related investigative and corrective actions in accordance with the
service bulletin.

Initial Lubrication

(i) At the latest of the compliance times specified in
paragraphs (i)(1), (i)(2), and (i)(3) of this AD, as applicable:
Lubricate the rudder and elevator components specified in the
service bulletin. Do all actions required by this paragraph in
accordance with the service bulletin.
(1) Within 9 months after the effective date of this AD, or
within 9 months since the date of issuance of the original standard
airworthiness certificate or the date of issuance of the original
export certificate of airworthiness; whichever occurs later.
(2) For airplanes on which BMS 3-33 grease is not already in use
prior to the time the lubrication task is being accomplished: Within
3,000 flight hours or 9 months after the last lubrication
accomplished in accordance with the service bulletin or Boeing
Special Attention Service Bulletin 767-27-0197 or 767-27-0198, both
dated October 27, 2005, whichever occurs first.
(3) For airplanes on which BMS 3-33 grease is already in use
prior to the time the lubrication task is being accomplished: Within
6,000 flight hours or 18 months after the last lubrication
accomplished in

[[Page 53704]]

accordance with the service bulletin or Boeing Special Attention
Service Bulletin 767-27-0197 or 767-27-0198, both dated October 27,
2005, whichever occurs first.

Repetitive Lubrication

(j) Repeat the lubrication required in paragraph (i) of this AD
at the applicable interval specified in paragraph (j)(1) or (j)(2)
of this AD.
(1) For airplanes on which BMS 3-33 grease is not already in use
prior to the time the lubrication task is being accomplished: At
intervals not to exceed 3,000 flight hours or 9 months, whichever
occurs first.
(2) For airplanes on which BMS 3-33 grease is already in use
prior to the time the lubrication task is being accomplished: At
intervals not to exceed 6,000 flight hours or 18 months, whichever
occurs first.

Repetitive Prior or Concurrent Inspection

(k) For airplanes specified in paragraphs (k)(1) and (k)(2) of
this AD: Prior to or concurrently with the accomplishment of each
elevator freeplay measurement specified in paragraph (g) of this AD,
do all applicable actions required by AD 2001-04-09.
(1) Group 1, configuration 2, airplanes as identified in Boeing
Special Attention Service Bulletin 767-27-0197, Revision 1, dated
July 19, 2007.
(2) Group 1, configuration 1, airplanes as identified in Boeing
Special Attention Service Bulletin 767-27-0198, Revision 1, dated
July 19, 2007.

Alternative Methods of Compliance (AMOCs)

(l)(1) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, has the authority to approve AMOCs for this AD, if requested in
accordance with 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.
(4) AMOCs approved previously in accordance with AD 2006-11-12
are approved as AMOCs for the corresponding provisions of this AD.
(5) AMOCs approved previously in accordance with AD 2001-04-09,
are approved as AMOCs for the corresponding provisions of paragraph
(k) of this AD.

Issued in Renton, Washington, on September 13, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E7-18544 Filed 9-19-07; 8:45 am]

BILLING CODE 4910-13-P