[Federal Register: April 5, 2007 (Volume 72, Number 65)]
[Proposed Rules]
[Page 16749-16752]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr05ap07-28]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2007-27776; Directorate Identifier 2006-NM-170-AD]
RIN 2120-AA64
Airworthiness Directives; Airbus Model A318, A319, A320, and A321
Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to supersede an existing airworthiness
directive (AD) that applies to all Airbus Model A318-100, A319-100,
A320-200, A321-100, and A321-200 series airplanes, and Model A320-111
airplanes. The existing AD currently requires an inspection to
determine whether certain braking and steering control units (BSCUs)
are installed or have ever been installed. For airplanes on which
certain BSCUs are installed or have ever been installed, the existing
AD requires an inspection of the nose landing gear (NLG) upper support
and corrective action if necessary, and a check of the NLG strut
inflation pressure and an adjustment if necessary. For some of these
airplanes, the existing AD also requires a revision to the aircraft
flight manual to incorporate an operating procedure to recover normal
steering in the event of a steering failure. This proposed AD would
require repetitive inspections of the NLG upper support, and related
investigative/corrective actions in accordance with new service
information; and would remove the one-time inspection that was required
by the existing AD. This proposed AD also would provide an optional
terminating action for the repetitive inspections. This proposed AD
results from a report of an incident where an airplane landed with the
NLG turned 90 degrees from centerline, and from additional reports of
NLG upper support anti-rotation lugs rupturing in service. We are
proposing this AD to prevent landings with the NLG turned 90 degrees
from centerline, which could result in reduced controllability of the
airplane.
DATES: We must receive comments on this proposed AD by May 7, 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: Docket Management Facility; U.S. Department of
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401,
Washington, DC 20590.
Fax: (202) 493-2251.
Hand Delivery: Room PL-401 on the plaza level of the
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
Contact Airbus, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex,
France, for service information identified in this proposed AD.
FOR FURTHER INFORMATION CONTACT: Tim Dulin, Aerospace Engineer,
International Branch, ANM-116, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425)
227-2141; fax (425) 227-1149.
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-2007-27776; Directorate Identifier 2006-NM-170-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 you
may 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 Management Facility office
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The Docket Management Facility office (telephone (800) 647-
5227) is located on the plaza level of the Nassif Building at the DOT
street address stated in the ADDRESSES section. Comments will be
available in the AD docket shortly after the Docket Management System
receives them.
Discussion
On November 16, 2005, we issued AD 2005-24-06, amendment 39-14386
(70 FR 70715, November 23, 2005), for all Airbus Model A318-100, A319-
100, A320-200, A321-100, and A321-200 series airplanes, and Model A320-
111 airplanes. That AD requires an inspection to determine whether
certain braking and steering control units (BSCUs) are installed or
have ever been installed. For airplanes on which certain BSCUs are
installed or have ever been installed, that AD requires an inspection
of the nose landing gear (NLG) upper support and corrective action if
necessary, and a check of the NLG strut inflation pressure and an
adjustment if necessary. For some of these airplanes, that AD also
requires a revision to the aircraft flight manual (AFM) to incorporate
an operating procedure to recover normal steering in the event of a
steering failure. That AD resulted from a report of an incident where
an airplane landed with the NLG turned 90 degrees from centerline. We
issued that AD to prevent landings with the NLG turned 90 degrees from
centerline, which could result in reduced controllability of the
airplane.
Actions Since Existing AD Was Issued
Since we issued AD 2005-24-06, several additional NLG upper support
anti-rotation lugs have ruptured in service, which could lead to the
inability to retract the NLG and possible landings with the nose wheel
turned 90 degrees from centerline. Investigations showed that the
affected airplanes were all equipped with enhanced manufacturing and
maintainability (EMM) BSCU (Standard L4.1 and L4.5). The NLG shock
absorber was also found to be over-pressurized on some of these
airplanes, which resulted in increased loads on the upper support. As a
result,
[[Page 16750]]
the manufacturer developed a repetitive boroscope inspection of the NLG
upper support lugs and cylinder lugs to replace the one-time
inspection, and an optional terminating action for the repetitive
inspections.
Relevant Service Information
Airbus has issued Service Bulletin A320-32-1310, dated February 8,
2006. The service bulletin describes procedures for doing a records
review to determine if the airplane is equipped with or has ever been
equipped with an EMM BSCU. For those airplanes that are equipped with
an EMM BSCU, the service bulletin describes procedures for doing a
repetitive special detailed inspection (boroscopic) for broken or
cracked NLG upper support lugs and missing cylinder lugs, and related
investigative/corrective actions. The related investigative/corrective
actions follow:
If the upper support anti-rotation lugs are broken or
cracked, or if a cylinder lug is missing: Do a pressure check of the
NLG shock absorber (weight on and weight off wheels); report the
measured pressure, `H' dimension, temperature, and boroscopic
inspection findings to Airbus for further assessment; and restore the
NLG in accordance with Airbus recommendations.
If there are no findings: At the initial threshold
inspection, do a servicing check (weight on wheels) of the NLG shock
absorber. If the pressure is not within permissible tolerance, adjust
the pressure and do the servicing check again with the weight off the
wheels. If the pressure is not within permissible tolerance with the
weight off the wheels, do a full service of the NLG shock absorber. The
service bulletin states that it is not necessary to do these actions
again at the repetitive intervals unless there is a finding during the
boroscopic inspection.
The European Aviation Safety Agency (EASA), which is the Technical
Agent for the Member States of the European Community, mandated the
service information and issued EASA Airworthiness Directive 2006-0174,
dated June 21, 2006, to ensure the continued airworthiness of these
airplanes in the European Union.
FAA's Determination and Requirements of the Proposed AD
These airplane models are manufactured in France and are type
certificated for operation in the United States under the provisions of
section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and
the applicable bilateral airworthiness agreement. As described in FAA
Order 8100.14A, ``Interim Procedures for Working with the European
Community on Airworthiness Certification and Continued Airworthiness,''
dated August 12, 2005, EASA has kept the FAA informed of the situation
described above. We have examined EASA's findings, evaluated all
pertinent information, and determined that AD action is necessary for
airplanes of this type design that are certificated for operation in
the United States.
This proposed AD would supersede AD 2005-24-06 and would retain the
requirements of the existing AD, except for the boroscope inspection
required within 90 days specified in paragraph (i)(2), and the repair
requirements of paragraph (j) of AD 2005-24-06. This proposed AD would
also require accomplishing the actions specified in the service
information described previously, except as discussed under
``Differences among the Proposed AD, the EASA Airworthiness Directive,
and the Service Bulletin.''
Differences Among the Proposed AD, the EASA Airworthiness Directive,
and the Service Bulletin
The service bulletin specifies to contact the manufacturer for
further assessment of the reported measured pressure, `H' dimension,
temperature, and boroscope inspection findings of the NLG shock
absorber, but this proposed AD does not require such reporting and
assessment. The service bulletin also specifies restoring the NLG in
accordance with Airbus recommendations, but this proposed AD would
require restoring the NLG in accordance with a method approved by the
FAA or the EASA (or its delegated agent).
Changes to Existing AD
We have changed the airplane model designations in the
applicability and in paragraph (f), ``Records Review,'' of this
proposed AD to be consistent with the parallel EASA airworthiness
directive.
We have clarified paragraph (f) of this proposed AD to refer to
BSCU standard L4.1 and L4.5, and added that Airbus Service Bulletin
A320-32-1310, dated February 8, 2006, is one approved method for doing
the records review.
Costs of Compliance
This proposed AD would affect about 720 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
----------------------------------------------------------------------------------------------------------------
Action Work hours Parts Cost per airplane Fleet cost
----------------------------------------------------------------------------------------------------------------
Records review (required by AD 1 None................ $80................ $57,600.
2005-24-06).
AFM revision (required by AD 1 None................ $80................ $57,600.
2005-24-06).
Special detailed inspection in 1 None................ $80,............... $57,600, per
accordance with new service per inspection inspection cycle.
information (new proposed cycle.
action).
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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 have determined that this proposed AD would not have federalism
implications under Executive Order 13132. This proposed AD would not
[[Page 16751]]
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 39-14386 (70 FR 70715, November 23, 2005) and adding
the following new airworthiness directive (AD):
Airbus: Docket No. FAA-2007-27776; Directorate Identifier 2006-NM-
170-AD.
Comments Due Date
(a) The FAA must receive comments on this AD action by May 7,
2007.
Affected ADs
(b) This AD supersedes AD 2005-24-06.
Applicability
(c) This AD applies to all Airbus Model A318, A319, A320, and
A321 airplanes.
Unsafe Condition
(d) This AD results from a report of an incident where an
airplane landed with the nose landing gear (NLG) turned 90 degrees
from centerline, and from additional reports of NLG upper support
anti-rotation lugs rupturing in service. We are issuing this AD to
prevent landings with the NLG turned 90 degrees from centerline,
which could result in reduced controllability 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.
Restatement of Certain Requirements of AD 2005-24-06
Records Review
(f) Within 5 days after November 30, 2005 (the effective date of
AD 2005-24-06), perform a records review to determine whether the
airplane is equipped with or has ever been equipped with an enhanced
manufacturing and maintainability (EMM) braking and steering control
unit (BSCU) part number (P/N) E21327001 (standard L4.1, installed by
Airbus Modification 26965, or Airbus Service Bulletin A320-32-1912)
or P/N E21327003 (standard L4.5, installed by Airbus Modification
33376, or Airbus Service Bulletin A320-32-1261). Airbus Service
Bulletin A320-32-1310, dated February 8, 2006, is one approved
method for doing the records review.
(g) For airplanes on which a records review required by
paragraph (f) of this AD conclusively determines that the airplane
is not and never has been equipped with a BSCU P/N E21327001 or P/N
E21327003, no further action is required by this AD.
Airplane Flight Manual (AFM) Revision
(h) For airplanes that are not specified in paragraph (g) of
this AD and on which Airbus Modification 31152 has not been
incorporated in production (i.e., applicable only to aircraft with
steering powered by the green hydraulic system): Within 10 days
after November 30, 2005, revise the Limitation Section of the Airbus
A318/319/320/321 Aircraft Flight Manual (AFM) to include the
following information. This may be done by inserting a copy of this
AD into the AFM:
``The ECAM message, in case of a nose wheel steering failure,
will be worded as follows:
--``WHEEL N/W STRG FAULT'' for aircraft with the FWC E3 and
subsequent standards
--``WHEEL N.W STEER FAULT'' for aircraft with the FWC E2 Standard.
If the L/G SHOCK ABSORBER FAULT ECAM caution is
triggered at any time in flight, and the WHEEL N/W STRG FAULT ECAM
caution is triggered after the landing gear extension:
When all landing gear doors are indicated closed on
ECAM WHEEL page, reset the BSCU:
--A/SKID&N/W STRG--OFF THEN ON
If the WHEEL N/W STRG FAULT ECAM caution is no longer
displayed, this indicates a successful nose wheel re-centering and
steering recovery.
Rearm the AUTO BRAKE, if necessary.
If the WHEEL N/W STRG FAULT ECAM caution remains
displayed, this indicates that the nose wheel steering remains lost,
and that the nose wheels are not centered.
--During landing, delay nose wheel touchdown for as long as
possible.
--Refer to the ECAM STATUS.
If the WHEEL N/W STRG FAULT ECAM caution appears,
without the L/G SHOCK ABSORBER FAULT ECAM caution:
--No specific crew action is requested by the WHEEL N/W STRG
FAULT ECAM caution procedure.
--Refer to the ECAM STATUS.''
Note 1: When a statement identical to that in paragraph (h) of
this AD has been included in the general revisions of the AFM, the
general revisions may be inserted into the AFM, and the copy of this
AD may be removed from the AFM.
New Requirements of This AD
Inspection Thresholds
(i) For airplanes that are not specified in paragraph (g) of
this AD, at the earlier of the times specified in paragraphs (i)(1)
and (i)(2) of this AD: Do a special detailed inspection (boroscopic)
for broken or cracked NLG upper support lugs and missing cylinder
lugs, and do all applicable related investigative/corrective actions
before further flight. Do all actions in accordance with Airbus
Technical Note 957.1901/05, dated October 18, 2005, or the
Accomplishment Instructions of Airbus Service Bulletin A320-32-1310,
dated February 8, 2006. After the effective date of this AD, only
Airbus Service Bulletin A320-32-1301, dated February 8, 2006, may be
used. Where the service bulletin specifies that restoring the NLG is
necessary in accordance with Airbus recommendations, this AD
requires restoring the NLG in accordance with a method approved by
the Manager, International Branch, ANM-116, Transport Airplane
Directorate, FAA; or the European Aviation Safety Agency (EASA) (or
its delegated agent). Repeat the inspection thereafter at the
applicable interval specified in paragraph (j) or (k) of this AD.
(1) Within 100 flight cycles following an electronic centralized
aircraft monitoring (ECAM) caution ``L/G SHOCK ABSORBER FAULT''
associated with at least one of the following centralized fault
display system (CFDS) messages specified in paragraph (i)(1)(i),
(i)(1)(ii), or (i)(1)(iii) of this AD.
(i) ``N L/G EXT PROX SNSR 24GA TGT POS.''
(ii) ``N L/G EXT PROX SNSR 25GA TGT POS.''
(iii) ``N L/G SHOCK ABSORBER FAULT 2526GM.''
(2) At the later of the times specified in paragraphs (i)(2)(i)
and (i)(2)(ii) of this AD.
(i) Within 20 months, 6,000 flight hours, or 4,500 flight cycles
since the date of issuance of the original French standard
airworthiness certificate, or French export certificate of
airworthiness, whichever occurs first.
(ii) Within 6 months, 1,800 flight hours, or 1,350 flight cycles
after the effective date of this AD, whichever occurs first.
Repetitive Inspection Intervals
(j) For airplanes not specified in paragraph (g) of this AD that
are equipped with EMM BSCU standard L4.1 or L4.5: Repeat the
inspection specified in paragraph (i) of this AD thereafter at
intervals not to exceed the earliest of 6 months; 1,800 flight
hours; 1,350
[[Page 16752]]
flight cycles; or 100 flight cycles following certain ECAM cautions
and CFDS messages, as specified in paragraph (i)(1) of this AD.
(k) For airplanes not specified in paragraph (g) of this AD that
are equipped with EMM BSCU standard L4.8 or a non-EMM BSCU: Repeat
the inspection specified in paragraph (i) of this AD thereafter at
intervals not to exceed the earliest of 20 months; 6,000 flight
hours; 4,500 flight cycles; or 100 flight cycles following certain
ECAM cautions and CFDS messages, as specified in paragraph (i)(1) of
this AD.
Note 2: For the purposes of this AD, a special detailed
inspection is: ``An intensive examination of a specific item,
installation, or assembly to detect damage, failure, or
irregularity. The examination is likely to make extensive use of
specialized inspection techniques and/or equipment. Intricate
cleaning and substantial access or disassembly procedure may be
required.''
Optional Terminating Action
(l) For airplanes that are not specified in paragraph (g) of
this AD: Installation of an NLG with new upper support anti-rotation
lugs and new cylinder lugs, or installation of an NLG that was never
driven by EMM BSCU standard L4.1 and L4.5; combined with
installation of an EMM BSCU standard L4.8 or a non-EMM BSCU;
constitutes terminating action for the requirements of this AD. Do
the installations in accordance with a method approved by either the
Manager, International Branch, ANM-116; or the EASA (or its
delegated agent). Chapter 32 of the Airbus A318/A319/A320/A321
Aircraft Maintenance Manual (AMM) is one approved method for doing
the installations.
No Report Required
(m) Although Airbus Service Bulletin A320-32-1310, dated
February 8, 2006, specifies sending certain inspection results to
Airbus, this AD does not include that requirement.
Credit Paragraph
(n) Inspections done before the effective date of this AD in
accordance with Chapter 12, Subject 12-14-32 of the Airbus A318/
A319/A320/A321 AMM, as revised by Airbus A318/A319/A320/A321 AMM
Temporary Revision 12-001, dated November 13, 2005, are acceptable
for compliance with the requirements of paragraph (i) of this AD.
Alternative Methods of Compliance (AMOCs)
(o)(1) The Manager, International Branch, ANM-116, has the
authority to approve AMOCs for this AD, if requested in accordance
with the procedures found in 14 CFR 39.19.
(2) Before using any AMOC approved in accordance with Sec.
39.19 on any airplane to which the AMOC applies, notify the
appropriate principal inspector in the FAA Flight Standards
Certificate Holding District Office.
Related Information
(p) EASA airworthiness directive 2006-0174, dated June 21, 2006,
also addresses the subject of this AD.
Issued in Renton, Washington, on March 26, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E7-6343 Filed 4-4-07; 8:45 am]
BILLING CODE 4910-13-P