AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

SUMMARY: We are adopting a new airworthiness directive (AD) for certain
Beechcraft Corporation (Type Certificate Previously Held by Hawker
Beechcraft Corporation; Raytheon Aircraft Company; Mitsubishi Heavy
Industries, Inc. Ltd.) Model MU-300 airplanes, and Beechcraft
Corporation (Type Certificate Previously Held by Hawker Beechcraft
Corporation; Raytheon Aircraft Company; Beech Aircraft Corporation)
Model 400, 400A, and 400T airplanes. This AD was prompted by multiple
reports of fatigue cracking in the horizontal stabilizer ribs. This AD
requires repetitive inspections of the horizontal stabilizer rib
assemblies for cracking, and replacement if necessary. We are issuing
this AD to detect and correct such cracking, which could result in the
failure of the horizontal stabilizer and loss of pitch control of the
airplane.

DATES: This AD is effective September 5, 2014.

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-
0187; 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: Paul Chapman, Aerospace Engineer,
Airframe Branch, ACE-118W, FAA, Wichita Aircraft Certification Office
(ACO), 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, KS
67209; phone: 316-946-4152; fax: 316-946-4107; email:
paul.chapman@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 Beechcraft
Corporation (Type Certificate Previously Held by Hawker Beechcraft
Corporation; Raytheon Aircraft Company; Mitsubishi Heavy Industries,
Inc. Ltd.) Model MU-300 airplanes Type Certificate previously held by
Mitsubishi; Raytheon Aircraft Company) Model MU-300 airplanes, and
Hawker Beechcraft Corporation (Type Certificate Previously Held by
Hawker Beechcraft Corporation; Raytheon Aircraft Company; Beech
Aircraft Corporation) Model 400, 400A, and 400T airplanes. The NPRM
published in the Federal Register on April 4, 2014 (79 FR 18848). The
NPRM was prompted by multiple reports of fatigue cracking in the
horizontal stabilizer ribs. The NPRM proposed to require repetitive
inspections of the horizontal stabilizer rib assemblies for cracking,
and replacement if necessary. We are issuing this AD to detect and
correct such cracking, which could result in the failure of the
horizontal stabilizer and loss of pitch control of the airplane.

Comments

We gave the public the opportunity to participate in developing
this AD. We received no comments on the NPRM (79 FR 18848, April 4,
2014) or on the determination of the cost to the public.

Conclusion

We reviewed the relevant data 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 18848, April 4, 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 18848, April 4, 2014).

Costs of Compliance

We estimate that this AD affects 735 airplanes of U.S. registry.
We estimate the following costs to comply with this AD:

Estimated Costs

We estimate the following costs to do any necessary replacements
that would be required based on the results of the inspection. We have
no way of determining the number of aircraft that might need these
replacements:

On-Condition Costs

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):