AGENCY: Federal Aviation Administration
(FAA), DOT.
ACTION: Final rule.
SUMMARY: We are adopting a new airworthiness directive (AD) for
certain
The Boeing Company Model 737-600, -700, -700C, -800, and -900 series
airplanes. This AD was prompted by reports in which a single,
undetected, erroneous radio altimeter output caused the autothrottle to
enter landing flare retard mode prematurely on approach. This AD
requires removing certain autothrottle computers and installing a new
or reworked autothrottle computer. We are issuing this AD to prevent a
single, undetected, erroneous radio altimeter output from causing
premature autothrottle landing flare retard and subsequent loss of
automatic speed control, which could result in loss of control of the
airplane.
DATES: This AD is effective September 23, 2014.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of September
23, 2014.
ADDRESSES: For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 206-544-
5000, extension 1; fax 206-766-5680; Internet https://www.myboeingfleet.
com. You may view this referenced service information
at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW.,
Renton, WA 98057. For information on the availability of this material
at the FAA, call 425-227-2112.
Examining the AD Docket
You may examine the AD docket on the Internet at http://www.regulations.
gov by searching for and locating Docket No. FAA-2014-
0122; 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 AD, the regulatory evaluation, any comments received, and
other information. The address for the Docket Office (phone: 800-647-
5527) is Docket Management Facility, U.S. Department of Transportation,
Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200
New Jersey Avenue SE., Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Marie Hogestad, Aerospace Engineer,
Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft
Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356;
phone: 425-917-6418; fax: 425-917-6590; email: marie.hogestad@faa.gov.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 by adding an AD that would apply to certain The Boeing Company
Model 737-600, -700, -700C, -800, and -900 series airplanes. The NPRM
published in the Federal Register on March 3, 2014 (79 FR 11728). The
NPRM was prompted by reports in which a single, undetected, erroneous
radio altimeter output caused the autothrottle to enter landing flare
retard mode prematurely on approach. The NPRM proposed to require
removing certain autothrottle computers and installing a new or
reworked autothrottle computer. We are issuing this AD to prevent a
single, undetected, erroneous radio altimeter output from causing
premature autothrottle landing flare retard and subsequent loss of
automatic speed control, which could result in loss of control of the
airplane.
Comments
We gave the public the opportunity to participate in developing
this AD. The following presents the comments received on the NPRM (79
FR 11728, March 3, 2014) and the FAA's response to each comment.
Support for the NPRM (79 FR 11728, March 3, 2014)
Boeing and the National Transportation Safety Board (NTSB)
concurred with the NPRM (79 FR 11728, March 3, 2014).
Clarification of Effect of Winglet Installation
Aviation Partners Boeing stated that installation of winglets per
Supplemental Type Certificate (STC) ST00830SE does not affect the
accomplishment of the manufacturer's service instructions specified in
the NPRM (79 FR 11728, March 3, 2014).
Request To Change Cost Estimate
Kevin Lee, a private citizen, requested that we increase the cost
estimate of the NPRM (79 FR 11728, March 3, 2014). The commenter stated
that the cost will be significantly higher due to General Electric not
providing a free-of-charge upgrade to the autothrottle computer despite
this being a safety and reliability issue.
We disagree with increasing the cost estimate. The cost estimate
does not include parts cost for the autothrottle computer because it is
considered ``Parts and Materials Supplied by the Operator'' in Boeing
Alert Service Bulletin 737-22A1215, dated November 22, 2013. The
autothrottle computer software can be updated using a data loader on a
bench with specific equipment that is unique to the GE autothrottle
computer. However, since this autothrottle computer has been out of
production for over ten years, it is unlikely that operators will have
the capability to do the update themselves using a disc supplied by GE.
Therefore, GE anticipates that the majority of operators will return
their autothrottle computer to a GE service center for modification. As
an alternative, operators may purchase the autothrottle computer from
Boeing. Boeing Alert Service Bulletin 737-22A1215, dated November 22,
2013, does not give the cost and it is therefore not included in our
estimate. Since there are multiple ways for operators to get an updated
autothrottle computer, we have not included the cost of the
autothrottle computer in our estimate. We also do not control warranty
coverage. No change has been made to this final rule in this regard.
Request To Delay Issuance or Extend Compliance Time of Final Rule
Kevin Lee requested that we delay issuance of the final rule, or
extend the proposed 36-month compliance time specified in the NPRM (79
FR 11728, March 3, 2014). The commenter stated that Boeing has not
incorporated the new GE autothrottle computer having part number (P/N)
760SUE2-5 into their Boeing 737 Illustrated Parts Catalog (IPC) or the
Instructions for Continued Airworthiness documents.
We disagree with delaying issuance of this final rule. Paragraph
1.K. of Boeing Alert Service Bulletin 737-22A1215, dated November 22,
2013, identifies the Boeing 737 IPC as the only document affected by
replacement of the autothrottle computer. The new autothrottle computer
has been added to the IPC, therefore there is no need to delay issuance
of the final rule.
We also disagree with extending the 36-month compliance time. In
developing an appropriate compliance time for this action, we
considered the urgency associated with the subject unsafe condition,
the availability of required parts, and the practical aspect of
accomplishing the required modification within a period of time that
corresponds to the normal scheduled maintenance for most affected
operators. According to the manufacturer, an ample number of required
parts will be available to modify the U.S. fleet within the proposed
compliance time. However, under the provisions of paragraph (i) of this
final rule, we will consider requests for approval of an extension of
the compliance time if sufficient data are submitted to substantiate
that the new compliance time would provide an acceptable level of
safety.
We have not changed the AD in regard to either delaying the final
rule or extending the 36-month compliance time.
Conclusion
We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
this AD as proposed except for minor editorial changes. We have
determined that these minor changes:
Are consistent with the intent that was proposed in the
NPRM (79 FR 11728, March 3, 2014) for correcting the unsafe condition;
and
Do not add any additional burden upon the public than was
already proposed in the NPRM (79 FR 11728, March 3, 2014).
We also determined that these changes will not increase the
economic burden on any operator or increase the scope of this AD.
Costs of Compliance
We estimate that this AD affects 497 airplanes of U.S. registry.
We estimate the following costs to comply with this AD:
Estimated Costs
Action |
Labor cost |
Parts cost |
Cost per product |
Cost on U.S. operators |
Autothrottle computer replacement |
1 work-hour x $85 per hour =
$85. |
$0
|
$85
|
$42,245
|
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
This AD will not have federalism implications under Executive Order
13132. This AD will 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 this AD:
(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),
(3) Will not affect intrastate aviation in Alaska, and
(4) 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.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 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 airworthiness
directive (AD):
|