

[Federal Register: October 26, 2007 (Volume 72, Number 207)]
[Proposed Rules]               
[Page 60790-60793]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr26oc07-18]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-28956; Directorate Identifier 2007-CE-068-AD]
RIN 2120-AA64

 
Airworthiness Directives; Cessna Aircraft Company Models 525, 
525A, and 525B Airplanes

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

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for 
certain Cessna Aircraft Company (Cessna) Models 525, 525A, and 525B 
airplanes. This proposed AD would require you to inspect the lower wing 
skin structure, forward wing spar, lower fuselage skin, fairings, and 
the external fairing frames for corrosion; repair any damage found; 
apply a corrosion inhibitive sealant to the fuselage fairings before 
reinstalling; and disable the cockpit mounted pilot relief tube. This 
proposed AD results from leaking of the cockpit mounted pilot relief 
tube, which caused corrosion of the airplane structure. We are 
proposing this AD to detect and correct any damage from corrosion of 
the airplane structure. Corrosion of the airplane structure could cause 
structural degradation and lead to structural failure of the airplane 
with consequent loss of control.

DATES: We must receive comments on this proposed AD by December 26, 
2007.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD:
     Federal eRulemaking Portal: Go to http://www.regulations.gov.
 Follow the instructions for submitting comments.

     Fax: (202) 493-2251.

[[Page 60791]]

     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.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this proposed AD, contact 
Cessna Aircraft Company, Citation Marketing Division, P.O. 7706, 
Wichita, Kansas 67277; telephone: 1-800-835-4090; fax: 1-800-517-8500.

FOR FURTHER INFORMATION CONTACT: T.N. Baktha, Aerospace Engineer, 1801 
Airport Road, Room 100, Wichita, Kansas 67209; telephone: (316) 946-
4155; fax: (316) 946-4107.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include the docket number, ``FAA-
2007-28956; Directorate Identifier 2007-CE-068-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://www.regulations.gov
, including any personal information you provide. We 

will also post a report summarizing each substantive verbal contact we 
receive concerning this proposed AD.

Discussion

    Cessna reported wing skin corrosion in a Model 525 and belly skin 
corrosion in several Model 525A airplanes. Cessna received information 
on more than 18 cases of significant corrosion. Cessna also received 
information on 42 cases of some corrosion on Models 525, 525A, and 525B 
airplanes. Corrosive fluids leaked after use of the cockpit mounted 
pilot relief tube and caused corrosion of the fuselage skins, fairings, 
fairing support structure, and wing structure.
    This condition, if not corrected, could result in structural 
degradation and lead to structural failure of the airplane with 
consequent loss of control.

Relevant Service Information

    We have reviewed the following Cessna service information for this 
AD:
     Service Bulletin SB525-53-20, dated April 30, 2007;
     Service Bulletin SB525A-53-01, dated April 30, 2007;
     Service Bulletin SB525B-53-01, dated April 30, 2007;
     Alert Service Letter ASL525-53-04, Revision 2, dated 
August 19, 2007;
     Alert Service Letter ASL525A-53-05, Revision 2, dated July 
25, 2007; and
     Alert Service Letter ASL525B-53-02, Revision 2, dated July 
25, 2007.
    The service information describes procedures for the following 
actions:
     Inspecting the lower wing skin structure, forward wing 
spars, lower fuselage skin, fairings, and external fairing frames for 
corrosion;
     Repairing corrosion by blending within specified limits or 
by contacting the manufacturer to obtain an FAA-approved repair scheme 
if corrosion damage can not be repaired within the limits specified;
     Doing a surface eddy current inspection or a dye-penetrant 
inspection on the repaired blended areas for cracks, and contacting the 
manufacturer to obtain an FAA-approved repair scheme if cracks are 
found;
     Applying a corrosion inhibitive sealant to the fuselage 
fairings before reinstalling; and
     Disabling the cockpit mounted relief tube.

FAA's Determination and Requirements of the Proposed AD

    We are proposing this AD because we evaluated all information and 
determined the unsafe condition described previously is likely to exist 
or develop on other products of the same type design. This proposed AD 
would require you to inspect the lower wing skin structure, forward 
wing spar, lower fuselage skin, fairings, and the external fairing 
frames for corrosion; repair any damage found; apply a corrosion 
inhibitive sealant to the fuselage fairings before reinstalling; and 
disable the cockpit mounted pilot relief tube.

Costs of Compliance

    We estimate that this proposed AD would affect 261 airplanes in the 
U.S. registry.
    We estimate the following costs to do the proposed inspection:

----------------------------------------------------------------------------------------------------------------
                                                                                  Total cost per   Total cost on
                  Labor cost                               Parts cost                airplane     U.S. operators
----------------------------------------------------------------------------------------------------------------
80 work-hours x $80 per hour = $6,400.........  Not Applicable..................          $6,400      $1,670,400
----------------------------------------------------------------------------------------------------------------

    We have no way of determining the number of airplanes that may need 
repair or further inspection based on the results of the proposed 
inspection, or the costs associated with such repair or inspection.
    We estimate the following costs to do the proposed disabling of the 
cockpit mounted pilot relief tube:

----------------------------------------------------------------------------------------------------------------
                                                                                  Total cost per   Total cost on
                  Labor cost                               Parts cost                airplane     U.S. operators
----------------------------------------------------------------------------------------------------------------
.5 work-hours x $80 per hour = $40............  Not Applicable..................             $40         $10,440
----------------------------------------------------------------------------------------------------------------

    Cessna will provide warranty credit to the extent specified in 
Cessna Citation Service Bulletin SB525-53-20, dated April 30, 2007; 
Service Bulletin SB525A-53-01, dated April 30, 2007; Service Bulletin 
SB525B-53-01, dated April 30, 2007; Alert Service Letter ASL525-53-04, 
Revision 2, dated August 19, 2007; Alert Service Letter ASL525A-53-05, 
Revision 2, dated July 25, 2007; and Alert Service Letter ASL525B-53-
02, Revision 2, dated July 25, 2007.

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

[[Page 60792]]

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.

Examining the AD Docket

    You may examine the AD docket that contains the proposed AD, the 
regulatory evaluation, any comments received, and other information on 
the Internet at http://www.regulations.gov; or in person at the Docket 

Management Facility between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The Docket Office (telephone (800) 647-5527) 
is located at the street address stated in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.

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 FAA amends Sec.  39.13 by adding the following new AD:

Cessna Aircraft Company: Docket No. FAA-2007-28956; Directorate 
Identifier 2007-CE-068-AD.

Comments Due Date

    (a) We must receive comments on this airworthiness directive 
(AD) action by December 26, 2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to the following airplane models and serial 
numbers that have a cockpit mounted pilot relief tube installed and 
are certificated in any category:

------------------------------------------------------------------------
               Models                             Serial Nos.
------------------------------------------------------------------------
(1) 525.............................  0001 through 0637.
(2) 525A............................  0001 through 0347.
(3) 525B............................  0001 through 0152.
------------------------------------------------------------------------

Unsafe Condition

    (d) This AD results from leaking of the pilot relief tube, which 
caused corrosion of the airplane structure. We are issuing this AD 
to detect and correct any damage from corrosion on the airplane 
structure. Corrosion of the airplane structure could cause 
structural degradation and lead to structural failure of the 
airplane with consequent loss of control.

Compliance

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

------------------------------------------------------------------------
             Actions                  Compliance          Procedures
------------------------------------------------------------------------
(1) Inspect the lower wing skin   Within the next 90  Follow Cessna
 structure, forward wing spars,    days after the      Citation Alert
 lower fuselage skin, fairings,    effective date of   Service Letter
 and external fairing frames for   this AD.            ASL525-53-04,
 corrosion.                                            Revision 2, dated
                                                       August 19, 2007;
                                                       Alert Service
                                                       Letter ASL525A-53-
                                                       05, Revision 2,
                                                       dated July 25,
                                                       2007; or Alert
                                                       Service Letter
                                                       ASL525B-53-02,
                                                       Revision 2, dated
                                                       July 25, 2007.
(2) If corrosion damage is found  Before further      Follow Cessna
 in the lower wing skin            flight after the    Citation Alert
 structure, forward wing spars,    inspection          Service Letter
 lower fuselage skin, fairings,    required in         ASL525-53-04,
 and external fairing frames       paragraph (e)(1)    Revision 2, dated
 during the inspection required    of this AD.         August 19, 2007;
 in paragraph (e)(1) of this AD,                       Alert Service
 repair as specified in the                            Letter ASL525A-53-
 applicable service information.                       05, Revision 2,
 If the corrosion damage can not                       dated July 25,
 be repaired within the limits                         2007; or Alert
 specified in the applicable                           Service Letter
 service information, contact                          ASL525B-53-02,
 the manufacturer at 1-800-835-                        Revision 2, dated
 4090 for an FAA-approved repair                       July 25, 2007.
 scheme and incorporate this
 repair.
(3) If corrosion on the lower     Before further      Follow Cessna
 wing skin structure, forward      flight after the    Citation Alert
 wing spars, and lower fuselage    repair by           Service Letter
 skin was repaired by blending     blending was done   ASL525-53-04,
 within the limits specified in    as specified in     Revision 2, dated
 the service information, do a     paragraph (e)(2)    August 19, 2007;
 surface eddy current inspection   of this AD.         Alert Service
 or a dye-penetrant inspection                         Letter ASL525A-53-
 for cracks.                                           05, Revision 2,
                                                       dated July 25,
                                                       2007; or Alert
                                                       Service Letter
                                                       ASL525B-53-02,
                                                       Revision 2, dated
                                                       July 25, 2007.
(4) If cracks are found during    Before further      Contact Cessna
 the surface eddy current          flight after the    Aircraft Company,
 inspection or the dye-penetrant   inspection          Citation Customer
 inspection required in            required in         Support at 1-800-
 paragraph (e)(3) of this AD,      paragraph (e)(3)    835-4090.
 contact the manufacturer for an   of this AD.
 FAA-approved repair scheme and
 incorporate this repair.

[[Page 60793]]


(5) Install the fuselage          Before further      Follow Cessna
 fairings and apply corrosion      flight after the    Citation Alert
 inhibitive sealant.               inspection          Service Letter
                                   required in         ASL525-53-04,
                                   paragraph (e)(1)    Revision 2, dated
                                   of this AD if no    August 19, 2007;
                                   corrosion was       Alert Service
                                   found; or before    Letter ASL525A-53-
                                   further flight      05, Revision 2,
                                   after doing the     dated July 25,
                                   repairs and         2007; or Alert
                                   inspections         Service Letter
                                   required in         ASL525B-53-02,
                                   paragraphs          Revision 2, dated
                                   (e)(2), (e)(3),     July 25, 2007.
                                   and (e)(4) of
                                   this AD if
                                   corrosion or
                                   cracks were found.
(6) Determine the type of         Within the next 90  Cessna Citation
 installation of the cockpit       days after the      Service Bulletin
 mounted pilot relief tube and     effective date of   SB525-53-20,
 disable the relief tube.          this AD.            dated April 30,
                                                       2007; Service
                                                       Bulletin SB525A-
                                                       53-01, dated
                                                       April 30, 2007;
                                                       or Service
                                                       Bulletin SB525B-
                                                       53-01, dated
                                                       April 30, 2007.
------------------------------------------------------------------------

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: T.N. Baktha, Wichita ACO, Aerospace Engineer, 1801 Airport 
Road, Room 100, Wichita, Kansas 67209; telephone: (316) 946-4155; 
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.

Related Information

    (g) To get copies of the service information referenced in this 
AD, contact Cessna Aircraft Company, Citation Marketing Division, 
P.O. 7706, Wichita, Kansas 67277; telephone: 1-800-835-4090; fax: 1-
800-517-8500. 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 

Docket No. FAA-2007-28956; Directorate Identifier 2007-CE-068-AD.

    Issued in Kansas City, Missouri, on October 22, 2007.
James E. Jackson,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E7-21127 Filed 10-25-07; 8:45 am]

BILLING CODE 4910-13-P
