[Federal Register Volume 69, Number 25 (Friday, February 6, 2004)]
[Proposed Rules]
[Pages 5756-5759]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-2403]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-CE-54-AD]
RIN 2120-AA64


Airworthiness Directives; The Cessna Aircraft Company Model 525 
Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede Airworthiness Directive (AD) 
2003-21-07, which applies to certain The Cessna Aircraft Company 
(Cessna) Model 525 airplanes. AD 2003-21-07 currently requires you to 
disengage the pitch trim circuit breaker and AP servo circuit breaker 
and then tie strap each of them to prevent them from being engaged. Not 
utilizing this equipment prevents a single-point failure. This proposed 
AD is the result of Cessna having now developed and made changes in the 
design of the affected trim printed circuit board (PCB) assembly to 
allow the use of the assembly and the prevention of the single-point 
failure, and identification of additional airplanes that have the same 
unsafe condition. Consequently, this proposed AD would require you to 
remove and replace an old trim PCB assembly with a new design assembly 
or modify an old trim PCB assembly to the new design. We are issuing 
this proposed AD to correct this single-point failure in the electric 
pitch trim system, which will result in a runaway pitch trim condition 
where the pilot could not disconnect using the control wheel autopilot/
trim disconnect switch. Failure of the electric trim system would 
result in a large pitch mistrim and would cause excessive control 
forces that the pilot could not overcome.

DATES: We must receive any comments on this proposed AD by April 15, 
2004.

ADDRESSES: Use one of the following to submit comments on this proposed 
AD:
     By mail: FAA, Central Region, Office of the 
Regional Counsel, Attention: Rules Docket No. 2003-CE-54-AD, 901 
Locust, Room 506, Kansas City, Missouri 64106.
     By fax: (816) 329-3771.
     By e-mail: [email protected]. Comments sent 
electronically must contain ``Docket No. 2003-CE-54-AD'' in the subject 
line. If you send comments electronically as attached electronic files, 
the files must be formatted in Microsoft Word 97 for Windows or ASCII.
    You may get the service information identified in this proposed AD 
from The Cessna Aircraft Company, Product Support, P.O. Box 7706, 
Wichita, Kansas 67277; telephone: (316) 517-6000; facsimile: (316) 517-
8500.
    You may view the AD docket at FAA, Central Region, Office of the 
Regional Counsel, Attention: Rules Docket No. 2003-CE-54-AD, 901 
Locust, Room 506, Kansas City, Missouri 64106. Office hours are 8 a.m. 
to 4 p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Dan Withers, Aerospace Engineer, 
Wichita Aircraft Certification Office, FAA, 1801 Airport Road, Wichita, 
Kansas 67209; telephone: (316) 946-4196; facsimile: (316) 946-4107.

SUPPLEMENTARY INFORMATION:

Comments Invited

    How do I comment on this proposed AD? We invite you to submit any 
written relevant data, views, or arguments regarding this proposal. 
Send your comments to an address listed under ADDRESSES. Include ``AD 
Docket No. 2003-CE-54-AD'' in the subject line of your comments. If you 
want us to acknowledge receipt of your mailed comments, send us a self-
addressed, stamped postcard with the docket number written on it. We 
will date-stamp your postcard and mail it back to you.
    Are there any specific portions of this proposed AD I should pay 
attention to? We specifically invite comments on the overall 
regulatory, economic, environmental, and energy aspects of this 
proposed AD. If you contact us through a nonwritten communication and 
that contact relates to a substantive part of this proposed AD, we will 
summarize the contact and place the summary in the docket. We will 
consider all comments received by the closing date and may amend this 
proposed AD in light of those comments and contacts.

Discussion

    Has FAA taken any action to this point? A report of an accident 
involving a Cessna Model 525 airplane where the pilot reported a 
problem with the pitch trim system, and later Cessna and FAA analysis 
that revealed the potential for a single-wire shorting caused us to 
issue AD 2003-21-07, Amendment 39-13342 (68 FR 60028, October 21, 
2003). AD 2003-21-07 currently requires you to do the following on 
Cessna Model 525 airplanes:

--Disengage the pitch trim circuit breaker and AP servo circuit 
breaker; and
--Tie strap each of them to prevent them from being engaged.

    What has happened since AD 2003-21-07 to initiate this proposed 
action? AD 2003-21-07 is considered an interim action since compliance 
corrected the condition where the control wheel autopilot/trim 
disconnect switch did not stop the runaway condition. However, AD 2003-
21-07 did not correct the issue of the single-point failure while still 
utilizing the desired equipment. Cessna has now developed and made 
changes in the design of the affected trim printed circuit board (PCB) 
assembly to eliminate the single-point failure while allowing the use 
of the equipment, and identified additional airplanes that have the 
same unsafe condition.
    What is the potential impact if FAA took no action? Failure of the 
electric trim system would result in a large pitch mistrim and would 
cause excessive

[[Page 5757]]

control forces that the pilot could not overcome.
    Is there service information that applies to this subject? Cessna 
has issued Citation Service Bulletin No. SB525-27-17, dated December 9, 
2003.
    What are the provisions of this service information? The service 
bulletin includes procedures for:

--Inspecting the electric elevator trim motor;
--Removing the trim PCB assembly;
--Modifying the trim PCB assembly;
--Installing a trim PCB assembly; and
--Removing any tie straps or extension caps installed on the AP servos 
and pitch trim circuit breakers.

FAA's Determination and Requirements of This Proposed AD

    What has FAA decided? We have evaluated all pertinent information 
and identified an unsafe condition that is likely to exist or develop 
on other products of this same type design. Therefore, we are proposing 
AD action.
    What would this proposed AD require? This proposed AD would 
supersede AD 2003-21-07 with a new AD that would require you to:

--Remove any 6518351-3 or 6518351-5 trim PCB assembly and replace with 
a 6518351-10 (EX) trim PCB assembly; or
--Modify the 6518351-8 trim PCB assembly to a 6518351-10 trim PCB 
assembly.

    How does the revision to 14 CFR part 39 affect this proposed AD? On 
July 10, 2002, we published a new version of 14 CFR part 39 (67 FR 
47997, July 22, 2002), which governs FAA's AD system. This regulation 
now includes material that relates to altered products, special flight 
permits, and alternative methods of compliance. This material 
previously was included in each individual AD. Since this material is 
included in 14 CFR part 39, we will not include it in future AD 
actions.

Costs of Compliance

    How many airplanes would this proposed AD impact? We estimate that 
this proposed AD affects 251 airplanes in the U.S. registry.
    What would be the cost impact of this proposed AD on owners/
operators of the affected airplanes? We estimate the following costs to 
accomplish this proposed modification of the 6518351-8 trim PCB 
assembly to a 6518351-10 trim PCB assembly. We have no way of 
determining the number of airplanes that may need this modification:

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                 Labor cost                   Parts cost                  Total cost per airplane
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4 workhours x $65 per hour = $260..........      $2,995.   $2,995+$260 = $3,255.
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    We estimate the following costs to accomplish this proposed 
replacement of any 6518351-3 or 6518351-5 trim PCB assembly with a 
6518351-10 (EX) trim PCB assembly. We have no way of determining the 
number of airplanes that may need this replacement:

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                 Labor cost                   Parts cost                  Total cost per airplane
----------------------------------------------------------------------------------------------------------------
2 workhours x $65 per hour = $130..........      $2,995.   $2,995+$130 = $3,125.
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    What is the difference between the cost impact of this proposed AD 
and the cost impact of AD 2003-21-07? The estimated cost impact of AD 
2003-21-07 on each of 116 airplanes in the U.S. registry is $65. This 
is to disengage the pitch trim circuit breaker and AP servo circuit 
breaker and then tie strap each of them to prevent them from being 
engaged.
    The estimated cost of this proposed AD is $3,125 or $3,255 on each 
of 251 airplanes in the U.S. registry to do the replacement or 
modification of the trim PCB assembly.

Compliance Time of This Proposed AD

    What would be the compliance time of this proposed AD? The 
compliance time of this proposed AD is within the next 24 calendar 
months after the effective date of this AD or within 300 hours time-in-
service (TIS) after the effective date of this AD, whichever occurs 
first.
    Why is the compliance time of this proposed AD presented in both 
hours TIS and calendar time? A single-wire shorting to 28 volts or a 
failure of a relay that results in the relay contacts remaining closed 
is a direct result of airplane operation. For example, either failure 
could occur on an affected airplane within a short period of airplane 
operation while you could operate another affected airplane for a 
considerable amount of time without experiencing either failure. 
Therefore, to assure that either failure is detected and corrected in a 
timely manner without inadvertently grounding any of the affected 
airplanes, we are using a compliance time based upon both hours TIS and 
calendar time.

Regulatory Findings

    Would this proposed AD impact various entities? 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.
    Would this proposed AD involve a significant rule or regulatory 
action? For the reasons discussed above, I certify that this proposed 
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 proposed AD 
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 
``AD Docket No. 2003-CE-54-AD'' in your request.

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 Federal Aviation Administration 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:


[[Page 5758]]


    Authority: 49 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. The FAA amends Sec. 39.13 by removing Airworthiness Directive 
(AD) 2003-21-07, Amendment 39-13342 (68 FR 60028, October 21, 2003), 
and by adding a new AD to read as follows:

The Cessna Aircraft Company: Docket No. 2003-CE-54-AD

When Is the Last Date I Can Submit Comments on This Proposed AD?

    (a) We must receive comments on this proposed airworthiness 
directive (AD) by April 15, 2004.

What Other ADs Are Affected by This Action?

    (b) This AD supersedes AD 2003-21-07.

What Airplanes Are Affected by This AD?

    (c) This AD affects Model 525 airplanes with the following 
serial numbers that are certificated in any category:
    (1) Group 1 (maintains the actions from AD 2003-21-07): 525-
0001, 525-0002, and 525-0004 through 525-0159.
    (2) Group 2: 525-0160 through 525-0359.

What Is the Unsafe Condition Presented in This AD?

    (d) This AD is the result of Cessna having now developed and 
made changes in the design of the affected trim printed circuit 
board (PCB) assembly to allow the use of the assembly and the 
prevention of the single-point failure, and identification of 
additional airplanes that have the same unsafe condition. The 
actions specified in this AD are intended to correct this single-
point failure in the electric pitch trim system, which will result 
in a runaway pitch trim condition where the pilot could not 
disconnect using the control wheel autopilot/trim disconnect switch. 
Failure of the electric trim system would result in a large pitch 
mistrim and would cause excessive control forces that the pilot 
could not overcome.

What Must I Do To Address This Problem?

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

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               Actions                             Compliance                            Procedures
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(1) For Group 1 airplanes only:       Within 5 calendar days or 10 hours    Not Applicable.
 Disengage the PITCH TRIM circuit      time-in-service after October 22,
 breaker located on the left circuit   2003 (the effective date of AD 2003-
 breaker panel. Install a tie strap    21-07), whichever occurs first.
 (part number (P/N) MS3367-1-4 or
 equivalent part number) on the
 shaft of the PITCH TRIM circuit
 breaker from being engaged.
(2) For Group 1 airplanes only:       Within 5 calendar days or 10 hours    Not Applicable.
 Disengage the AP SERVOS circuit       time-in-service after October 22,
 breaker located in the right          2003 (the effective date of AD 2003-
 circuit breaker panel. Install a      21-07), whichever occurs first.
 tie strap (P/N MS3367-1-4 or
 equivalent part number) on the
 shaft of the AP SERVOS circuit
 breaker to prevent the circuit
 breaker from being engaged.
(3) The Minimum Crew portion of       Not Applicable.                       Not Applicable.
 Section II--Operating Limitations
 of the Airplane Flight Manual (AFM)
 provides information on applicable
 operating limitations with the
 autopilot inoperable.
(4) All affected airplanes were       Not Applicable.                       Not Applicable.
 originally equipped with a P/N
 6518351-3 or P/N 65138351-5 Trim PC
 Board Assembly. If a P/N 6518351-8
 Trim PC Board Assembly is
 installed, contact the Wichita
 Aircraft Certification Office at
 the address in paragraph (f) of
 this AD to determine if the
 installed P/N 6518351-8 Trim PC
 board assembly is an alternative
 method of compliance to this AD.
(5) Cessna Citation Alert Service     Not Applicable.                       Not Applicable.
 Letter ASL525-27-02, dated October
 10, 2003, contains information
 related to this subject.
(6) For both Group 1 and Group 2      Within the next 24 calendar months    Follow the ACCOMPLISHMENT
 airplanes: Do the trim PCB assembly   after the effective date of this AD   INSTRUCTIONS paragraph of Cessna
 change as follows: (i) Modify the     or within 300 hours time-in-service   Citation Service Bulletin No. SB525-
 6518351-8 trim PCB assembly to a      (TIS) after the effective date of     27-17, dated December 9, 2003.
 6518351-10 trim PCB assembly; or      this AD, whichever occurs first,
 (ii) Replace any 6518351-3 trim PCB   unless already done.
 assembly with 6518351-10 (EX) trim
 PCB assembly.
(7) For both Group 1 and Group        Before further flight after the       Follow the ACCOMPLISHMENT
 airplanes: Remove any tie strap (P/   modification or replacement of the    INSTRUCTIONS paragraph of Cessna
 N MS3367-1-4 or equivalent part       trim PCB assembly required by         Citation Service Bulletin No. SB525-
 number) on the AP SERVOS and PITCH    paragraph (e)(6)(i) or (e)(6)(ii)     27-17, dated December 9, 2003.
 circuit breakers. (Required by AD     of this AD.
 2003-21-07.)
(8) For both Group 1 and Group 2      As of the effective date of this AD.  Not Applicable.
 airplanes: Do not install any
 6518351-8, 6518351-3, or 6518351-5
 trim PCB assembly.
----------------------------------------------------------------------------------------------------------------

May I Request an Alternative Method of Compliance?

    (f) You may request a different method of compliance or a 
different compliance time for this AD by following the procedures in 
14 CFR 39.19. Unless FAA authorizes otherwise, send your request to 
your principal inspector. The principal inspector may add comments 
and will send your request to the Manager, Wichita Aircraft 
Certification Office (ACO), FAA.
    (1) For information on any already approved alternative methods 
of compliance, contact Dan Withers, Aerospace Engineer, Wichita ACO, 
FAA, 1801 Airport Road, Wichita, Kansas 67209; telephone: (316) 946-
4196; facsimile: (316) 946-4107.
    (2) Alternative methods of compliance approved for AD 2003-21-07 
are not

[[Page 5759]]

approved as alternative methods of compliance for this AD.

May I Get Copies of the Documents Referenced in This AD?

    (g) You may get copies of the documents referenced in this AD 
from The Cessna Aircraft Company, Product Support, P.O. Box 7706, 
Wichita, Kansas 67277; telephone: (316) 517-6000; facsimile: (316) 
517-8500. You may view these documents at FAA, Central Region, 
Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, 
Missouri 64106.

    Issued in Kansas City, Missouri, on January 29, 2004.
Dorenda D. Baker,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 04-2403 Filed 2-5-04; 8:45 am]
BILLING CODE 4910-13-P