
[Federal Register: July 2, 2008 (Volume 73, Number 128)]
[Rules and Regulations]               
[Page 37783-37786]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr02jy08-5]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-28434; Directorate Identifier 2007-CE-053-AD; 
Amendment 39-15580; AD 2008-13-17]
RIN 2120-AA64

 
Airworthiness Directives; Hawker Beechcraft Corporation (Type 
Certificates No. 3A15, No. 3A16, No. A23CE, and No. A30CE Previously 
Held by Raytheon Aircraft Company) F33 Series and Models G33, V35B, 
A36, A36TC, B36TC, 95-B55, D55, E55, A56TC, 58, 58P, 58TC, G58, and 77 
Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA adopts a new airworthiness directive (AD) for certain 
Hawker Beechcraft Corporation F33 series and Models G33, V35B, A36, 
A36TC, B36TC, 95-B55, D55, E55, A56TC, 58, 58P, 58TC, G58, and 77 
airplanes. This AD requires you to replace certain circuit breaker 
toggle switches with improved design circuit breaker toggle switches. 
This AD results from reports of certain circuit breaker toggle switches 
used in various electrical systems throughout the affected airplanes 
overheating. We are issuing this AD to prevent failure of the circuit 
breaker toggle switch, which could result in smoke in the cockpit and 
the inability to turn off the switch.

DATES: This AD becomes effective on August 6, 2008.
    On August 6, 2008, the Director of the Federal Register approved 
the incorporation by reference of certain publications listed in this 
AD.

ADDRESSES: To get the service information identified in this AD, 
contact Hawker Beechcraft Corporation, 9709 East Central, Wichita, 
Kansas 67291; telephone: (800) 429-5372 or (316) 676-3140.
    To view the AD docket, go to U.S. Department of Transportation, 
Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 
New Jersey Avenue, SE., Washington, DC 20590, or on the Internet at 
http://www.regulations.gov. The docket number is FAA-2007-28434; 
Directorate Identifier 2007-CE-053-AD.

FOR FURTHER INFORMATION CONTACT: Jose Flores, Aviation Safety Engineer, 
Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, 
Wichita, Kansas 67209; telephone: (316) 946-4132; fax: (316) 946-4107.

SUPPLEMENTARY INFORMATION:

Discussion

    On June 29, 2007, we issued a proposal to amend part 39 of the 
Federal Aviation Regulations (14 CFR part 39) to include an AD that 
would apply to certain Hawker Beechcraft Corporation F33 series and 
Models G33, V35B, A36, A36TC, B36TC, 95-B55, D55, E55, A56TC, 58, 58P, 
58TC, G58, and 77 airplanes. This proposal was published in the Federal 
Register as a notice of proposed rulemaking (NPRM) on July 6, 2007 (72 
FR 36912). The NPRM proposed to require you to replace certain circuit 
breaker toggle switches with improved design circuit breaker toggle 
switches.

Comments

    We provided the public the opportunity to participate in developing 
this AD. The following presents the comments received on the proposal 
and FAA's response to each comment:

Comment Issue No. 1: Reopen the Comment Period

    The American Bonanza Society and six other commenters request more 
time to further investigate and evaluate replacing all circuit breaker 
switches in numerous models of Hawker Beechcraft piston airplanes. One 
commenter requests the extension to better research the number of 
service difficulty reports (SDRs), the number of airplanes affected, 
and the availability of replacement switches.
    We do not agree with the commenters. The failure mode creates an 
internal short circuit that will cause overheating. Testing of the 
circuit breaker switches revealed all the circuit breaker switches are 
susceptible to the failure mode and overheating.
    We have identified an unsafe condition and determined that 
reopening the comment period will only allow the unsafe condition to 
potentially go undetected. If any owner/operator identifies an 
alternative method of compliance (AMOC) to this AD that will provide a 
level of safety acceptable to the FAA, they can apply for an AMOC using 
the procedures outlined in 14 CFR 39.19 and this AD.
    We are not changing the final rule AD action based on these 
comments.

Comment Issue No. 2: Change Required Actions

    James Blodgett and Adam Dagys suggest that turning off the master 
switch would better eliminate the problem rather than replacing the 
circuit breaker switches.
    The commenters request that the FAA change the proposed AD action 
to mandate this change to prevent smoke in the cockpit.
    We do not agree with the commenters. Turning off the master switch 
may mitigate the overheating in some circuit breaker switches. However, 
in certain flight conditions, removing electrical power could create a 
more hazardous condition by disabling electrical equipment required for 
continued safe flight and landing, thus creating an additional unsafe 
condition.
    We are not changing the final rule AD action based on these 
comments.

Comment Issue No. 3: AD Unwarranted

    The American Bonanza Society, the Bonanza Service Ltd., KT Graham 
Inc., and eight other commenters state that the AD is unwarranted 
because failure of the affected circuit breaker switches is an uncommon 
occurrence and that there is no imminent threat to airplane occupants 
or the public.
    The commenters state that they have seen no or very few circuit 
breaker switch failures in the field. Of the thousands of affected 
airplanes and over 100,000 circuit breaker switches, none of these 
resulted in a reportable mishap.

[[Page 37784]]

High utilization fleet service has shown there is no significant threat 
of circuit breaker switch overheat.
    The commenters state that the testing done by Hawker Beechcraft and 
the FAA does not indicate a wider threat of failure, and failure in 
itself will not bring about a dangerous condition. Also, the only 
switches tested were those that had been previously squawked for 
overheating and removed under existing maintenance procedures.
    We disagree that an AD is unwarranted. A failed circuit breaker 
switch creating smoke and possible in-flight fire is considered a 
hazardous condition. Although failure of these circuit breaker switches 
is uncommon, we have received reports of failures occurring. The 
resulting hazardous safety effect combined with the number of 
occurrences and other factors indicate AD action is necessary. 14 CFR 
39.5 states that the ``FAA issues an AD addressing a product when we 
find that an unsafe condition exists in the product, and the condition 
is likely to exist or develop in products of the same type design.'' 
Even though the failures that have happened are uncommon, the condition 
``is likely to exist or develop'' on other affected airplanes. 
Therefore, AD action is necessary to address the unsafe condition 
following 14 CFR part 39.
    We are not changing the final rule AD action based on these 
comments.

Comment Issue No. 4: AD Is Too Costly

    The American Bonanza Society, Bonanza Service Ltd., KT Graham Inc., 
and seven other commenters state that because of the operational 
history of the affected airplanes and the uncommon occurrence of 
failure of the affected circuit breaker switches, the cost per airplane 
and per fleet appears to be too costly. Operational history does not 
warrant the cost or impact on the airplane owners/operators.
    We do not agree that the AD is not warranted because of the 
associated cost. We understand that ADs can be costly. However, we have 
determined that an unsafe condition is likely to exist or develop in 
other airplanes of the same type design, and the continued operational 
safety of the affected airplanes must be addressed. Therefore, issuing 
this AD and not allowing an unsafe condition to go undetected on the 
affected airplanes overrides the associated cost.
    We are not changing the final rule AD action based on these 
comments.

Comment Issue No. 5: Add Inspection or Testing Before Replacement

    Fred von Zabern and Adam Dagys request allowing inspection or 
testing to identify the overheating switches before replacement.
    Using a test or inspection to identify overheating switches may 
eliminate the need to replace all the switches in any given airplane. 
It may also eliminate replacing operable (good) switches.
    We do not agree with the commenters. Because of the failure mode, 
an over voltage test or inspection may not identify the failed circuit 
breaker switch. The failure condition identified is the failure of an 
internal wire braid that may create a short circuit inside the housing 
of the circuit breaker switch. The replacement circuit breaker switch 
includes added insulation around the wire braid to provide increased 
isolation and prevent the short circuit. We have determined that all 
the circuit breaker switches identified in the service information are 
susceptible to the overheating failure condition, and they need to be 
replaced to address this unsafe condition.
    We are not changing the final rule AD action based on these 
comments.

Comment Issue No. 6: Limit the Applicability of the AD

    The Aircraft Owners and Pilots Association (AOPA), the American 
Bonanza Society, and Bart Sisson request that we limit the 
applicability of the AD to Baron Models 58, 58G, 58P, and 58TC 
airplanes. The commenters also request that we limit the AD to the 
circuit breaker switches used in high electrical load items, such as 
lighting, taxi lights, and anti-ice equipment.
    The commenters state that the SDRs only affect high electrical load 
items and only Model 58 airplanes. There are no SDRs or operational 
history to show all circuit breaker switches are susceptible to the 
overheating. The airworthiness concern sheet identifies only those 
circuit breaker switches removed from high current circuits on Baron 
airplane models.
    We do not agree with the commenters. Although the circuit breaker 
switches that were reported, and used for the investigation, were 
removed from high electrical load items on Baron airplane models, there 
is no reason to believe the failure mode is limited to high electrical 
load circuits or Baron models. The failure mode creates an internal 
short circuit that will cause overheating regardless of the electrical 
load. Testing of the circuit breaker switches revealed all the circuit 
breaker switches are susceptible to the failure mode and overheating. 
Hawker Beechcraft Recommended Service Bulletin SB 24-3807, Issued: May 
2007, and Raytheon Aircraft Company Recommended Service Bulletin SB 24-
3735, Issued: August 2005, call out all the susceptible circuit breaker 
switches.
    We are not changing the final rule AD action based on these 
comments.

Comment Issue No. 7: Replacement Parts Not Available

    The American Bonanza Society states that there is a shortage of 
replacement switches available. Manufacturer parts availability shows a 
shortage of parts. The shortage would not be made up in time to prevent 
a large number of affected aircraft from being grounded due to the lack 
of replacement parts at the end of the 12-month compliance time.
    We do not agree with the commenter. Hawker Beechcraft has assured 
us that the replacement parts are either available or could be 
manufactured within the 12-month compliance time. If there becomes a 
shortage of parts, we would consider extending the compliance time 
following the AMOC procedures outlined in 14 CFR 39.19 and this AD.
    We are not changing the final rule AD action based on these 
comments.

Comment Issue No. 8: Promote Education Instead of Issuing a Regulation

    The American Bonanza Society suggests an improved level of safety 
would result from education in lieu of issuing a regulation.
    The commenter states that an educational effort to publicize 
Beech's guidance and generic electrical fire or overheat procedure for 
pilots whose pilot's operating handbook (POH) does not contain such a 
checklist would provide the information necessary to detect and respond 
in the uncommon event of a switch overheat condition. Beech technical 
support recommends monitoring the switches by feel to detect looseness 
and heat and to replace any switch that feels loose or hot to the 
touch.
    We do not agree with the commenter. An educational effort may 
improve awareness to the unsafe condition; however, it would not 
eliminate the failure mode. The only way to eliminate the failure mode 
is to replace the affected circuit breaker switches. We have determined 
that an education effort is insufficient to correct the unsafe 
condition.
    We are not changing the final rule AD action based on these 
comments.

[[Page 37785]]

Conclusion

    We have carefully reviewed the available data and determined that 
air safety and the public interest require adopting the AD as proposed 
except for minor editorial corrections. We have determined that these 
minor corrections:
     Are consistent with the intent that was proposed in the 
NPRM for correcting the unsafe condition; and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM.

Costs of Compliance

    We estimate that this AD affects 10,821 airplanes in the U.S. 
registry.
    We estimate the following costs to do the replacement:

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                                                                 Total cost per circuit    Total cost on  U.S.
              Labor cost                      Parts cost         breaker  toggle switch         operators
----------------------------------------------------------------------------------------------------------------
1 work-hour x $80 per hour = $80 per   $105 per circuit         $185 for each circuit    From $2,001,885 to
 circuit breaker toggle switch.         breaker toggle switch.   breaker toggle switch.   replace one circuit
                                                                 Each airplane            breaker toggle switch
                                                                 typically has more       per affected airplane
                                                                 than 1 circuit breaker   up to $30,028,275 to
                                                                 toggle switch            replace 15 circuit
                                                                 installed. Some          breaker toggle
                                                                 airplanes may have up    switches per airplane.
                                                                 to 15.
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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 AD.

Regulatory Findings

    We have determined that 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 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 summary of the costs to comply with this AD (and 
other information as included in the Regulatory Evaluation) and placed 
it in the AD Docket. You may get a copy of this summary by sending a 
request to us at the address listed under ADDRESSES. Include ``Docket 
No. FAA-2007-28434; Directorate Identifier 2007-CE-053-AD'' in your 
request.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the Federal Aviation Administration amends part 39 of the Federal 
Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. FAA amends Sec.  39.13 by adding a new AD to read as follows:

2008-13-17 Hawker Beechcraft Corporation (Type Certificates No. 
3A15, No. 3A16, No. A23CE, and No. A30CE previously held by Raytheon 
Aircraft Company) and Raytheon Aircraft Company: Amendment 39-15580; 
Docket No. FAA-2007-28434; Directorate Identifier 2007-CE-053-AD.

Effective Date

    (a) This AD becomes effective on August 6, 2008.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to the following airplane models and serial 
numbers that have a part number (P/N) 35-380132-1 through 35-380132-
53 circuit breaker toggle switch installed and are certificated in 
any category:

--------------------------------------------------------------------------------------------------------------------------------------------------------
                    Models                                                                     Serial Nos.
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(1) F33 and G33...............................  CD-1235 through CD-1304.
(2) F33A......................................  CE-290 through CE-1791.
(3) F33C......................................  CJ-26 through CJ-179.
(4) V35B......................................  D-9069 through D-10403.
(5) A36.......................................  E-185 through E-3629 and E-3631 through E-3635.
(6) A36TC and B36TC...........................  EA-1 through EA-695.
(7) 95-B55....................................  TC-1913, TC-1936 through TC-2456.
(8) D55.......................................  TE-452 through TE-767.
(9) E55.......................................  TE-768 through TE-1201.
(10) A56TC....................................  TG-84 through TG-94.
(11) 58.......................................  TH-1 through TH-2124.
(12) 58P......................................  TJ-3 through TJ-497.
(13) 58TC.....................................  TK-1 through TK-151.

[[Page 37786]]


(14) G58......................................  TH-2126, TH-2127, TH-2131 through TH-2134, TH-2136, TH-2137, TH-2139 through TH-2141, and TH-2143
                                                 through TH-2150.
(15) 77.......................................  WA-1 through WA-312.
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Unsafe Condition

    (d) This AD results from reports of certain circuit breaker 
toggle switches used in various electrical systems through the 
affected airplanes overheating. We are proposing this AD to prevent 
failure of the circuit breaker toggle switch, which could result in 
smoke in the cockpit and the inability to turn off the switch.

Compliance

    (e) To address this problem, you must do the following, unless 
already done:

------------------------------------------------------------------------
           Actions                 Compliance            Procedures
------------------------------------------------------------------------
(1) Replace all affected      Within the next 12    As specified in
 circuit breaker toggle        months after August   Hawker Beechcraft
 switches specified in         6, 2008 (the          Recommended Service
 paragraph (c) of this AD      effective date of     Bulletin SB 24-
 with an improved circuit      this AD).             3807, Issued: May
 breaker toggle switch, P/N                          2007, and Raytheon
 35-380132-61 through 35-                            Aircraft Company
 380132-113, as applicable.                          Recommended Service
                                                     Bulletin SB 24-
                                                     3735, Issued:
                                                     August 2005.
(2) Do not install a circuit  Before further        Not applicable.
 breaker toggle switch         flight after the
 specified in paragraph (c)    replacement
 of this AD.                   required by
                               paragraph (e)(1) of
                               this AD.
------------------------------------------------------------------------

Alternative Methods of Compliance (AMOCs)

    (f) The Manager, Wichita Aircraft Certification Office (ACO), 
FAA, has the authority to approve AMOCs for this AD, if requested 
using the procedures found in 14 CFR 39.19. Send information to 
ATTN: Jose Flores, Aviation Safety Engineer, FAA, Wichita ACO, 1801 
Airport Road, Room 100, Wichita, Kansas 67209; telephone: (316) 946-
4132; fax: (316) 946-4107. 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.

Material Incorporated by Reference

    (g) You must use Hawker Beechcraft Recommended Service Bulletin 
SB 24-3807, Issued: May 2007; and Raytheon Aircraft Company 
Recommended Service Bulletin SB 24-3735, Issued: August 2005, to do 
the actions required by this AD, unless the AD specifies otherwise.
    (1) The Director of the Federal Register approved the 
incorporation by reference of this service information under 5 
U.S.C. 552(a) and 1 CFR part 51.
    (2) For service information identified in this AD, contact 
Hawker Beechcraft Corporation, 9709 East Central, Wichita, Kansas 
67291; telephone: (800) 429-5372 or (316) 676-3140.
    (3) You may review copies at the FAA, Central Region, Office of 
the Regional Counsel, 901 Locust, Kansas City, Missouri 64106; or at 
the National Archives and Records Administration (NARA). For 
information on the availability of this material at NARA, call 202-
741-6030, or go to: http://www.archives.gov/federal_register/code_
of_federal_regulations/ibr_locations.html.

    Issued in Kansas City, Missouri, on June 16, 2008.
James E. Jackson,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E8-14090 Filed 7-1-08; 8:45 am]

BILLING CODE 4910-13-P
