[Federal Register Volume 68, Number 192 (Friday, October 3, 2003)]
[Proposed Rules]
[Pages 57394-57398]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-25089]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-CE-05-AD]
RIN 2120-AA64


Airworthiness Directives; Cessna Aircraft Company Models 401, 
401A, 401B, 402, 402A, 402B, 411, and 411A Airplanes

AGENCY: Federal Aviation Administration, Transportation.

ACTION: Supplemental notice of proposed rulemaking (NPRM); Reopening of 
the comment period.

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SUMMARY: This document proposes to revise an earlier proposed 
airworthiness directive (AD) that would supersede Airworthiness 
Directive (AD) 79-10-15

[[Page 57395]]

R2, which applies to all Cessna Aircraft Company (Cessna) Models 401, 
401A, 401B, 402, 402A, 402B, 411, and 411A airplanes. AD 79-10-15 R2 
currently requires repetitive inspections of the right and left wing 
spar lower cap areas for fatigue cracks and requires wing spar cap 
repair or replacement as necessary. Cessna has performed fatigue and 
crack growth analyses of the wings of these airplanes, and the Federal 
Aviation Administration (FAA) has evaluated this information and 
determined that a wing spar modification is necessary as well as 
periodic inspections. The earlier NPRM would have required you to 
repetitively inspect the wing spar caps for fatigue cracks with any 
necessary repair or replacement on all airplanes and incorporate a spar 
strap modification on each wing spar on certain airplanes. We received 
a request to reopen the comment period for this action in order to 
allow more time to evaluate the impact of the actions of the proposed 
AD. Therefore, we are reopening the comment period to allow the public 
additional time to comment on the proposed AD.

DATES: The Federal Aviation Administration (FAA) must receive any 
comments on this proposed rule on or before December 8, 2003.

ADDRESSES: Submit comments to FAA, Central Region, Office of the 
Regional Counsel, Attention: Rules Docket No. 2002-CE-05-AD, 901 
Locust, Room 506, Kansas City, Missouri 64106. You may view any 
comments at this location between 8 a.m. and 4 p.m., Monday through 
Friday, except Federal holidays. You may also send comments 
electronically to the following address: [email protected]. 
Comments sent electronically must contain ``Docket No. 2002-CE-05-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 text.
    You may get service information that applies to this proposed AD 
from the Cessna Aircraft Company, Product Support, P.O. Box 7706, 
Wichita, Kansas 67277; telephone: (316) 517-5800; facsimile: (316) 942-
9006. You may also view this information at the Rules Docket at the 
address above.

FOR FURTHER INFORMATION CONTACT: Paul Nguyen, Aerospace Engineer, FAA, 
Wichita Aircraft Certification Office, 1801 Airport Road, Mid-Continent 
Airport, Wichita, Kansas 67209; telephone: (316) 946-4125; facsimile: 
(316) 946-4107.

SUPPLEMENTARY INFORMATION: 

Comments Invited

How Do I Comment on This Proposed AD?

    The FAA invites comments on this proposed rule. You may submit 
whatever written data, views, or arguments you choose. You need to 
include the proposed rule's docket number and submit your comments to 
the address specified under the caption ADDRESSES. We will consider all 
comments received on or before the closing date. We may amend this 
proposed rule in light of comments received. Factual information that 
supports your ideas and suggestions is extremely helpful in evaluating 
the effectiveness of this proposed AD action and determining whether we 
need to take additional rulemaking action.

Are There Any Specific Portions of This Proposed AD I Should Pay 
Attention to?

    The FAA specifically invites comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed rule that 
might suggest a need to modify the rule. You may view all comments we 
receive before and after the closing date of the rule in the Rules 
Docket. We will file a report in the Rules Docket that summarizes each 
contact we have with the public that concerns the substantive parts of 
this proposed AD.

How Can I Be Sure FAA Receives My Comment?

    If you want FAA to acknowledge the receipt of your mailed comments, 
you must include a self-addressed, stamped postcard. On the postcard, 
write ``Comments to Docket No. 2002-CE-05-AD.'' We will date stamp and 
mail the postcard back to you.

Discussion

What Events Have Caused This Proposed AD?

    Reports of fatigue cracks on Cessna 401, 402, and 411 series 
airplanes caused FAA to take AD action (AD 79-10-15 R2, Amendment 39-
3711) to require repetitive inspections of the right and left wing spar 
lower cap areas for fatigue cracks and to require wing spar cap repair 
or replacement as necessary.
    Accomplishment of the inspections required by AD 79-10-15 R2 is 
required in accordance with Cessna Service Bulletin ME79-16, Revision 
3, dated February 8, 1980.
    AD 79-10-15 R2 allowed for the incorporation of Cessna Service Kit 
SK402-36 or SK411-56 on the front wing spar lower cap as terminating 
action for the repetitive inspections on the applicable wing.
    Since issuance of AD 79-10-15, Cessna has analyzed the wing, 
including fatigue and crack growth analyses, on the affected airplanes. 
Analysis included:
    [sbull] A determination of the probable location and modes of 
damage based on analytical results, available test data, and service 
information;
    [sbull] Classical fatigue analyses;
    [sbull] Crack growth and residual strength analyses including use 
of linear elastic fracture mechanics methods;
    [sbull] Full-scale ground testing to validate analytical models; 
and
    [sbull] A flight strain survey to develop stress spectra used in 
the analyses.
    The inspections required by AD 79-10-15 R2 in accordance with 
Cessna Service Bulletin ME79-16, Revision 3, are accomplished using a 
surface eddy current inspection method.
    Based on the analysis, Cessna has found that the eddy current 
method will not find the crack until it is .03 inch longer than the 
critical crack length. When the crack reaches the critical length, it 
is not reliably detectable because it is under the head of the 
fastener. Once the main spar cap is severed, the remaining structure 
will no longer meet the residual strength requirements. Wing separation 
could then occur under loading conditions significantly less than those 
established for the design limit load.
    Cessna reported only one instance where cracks were detected using 
the nondestructive inspection (NDI) eddy current procedure. There are 
other reported instances where cracks were detected visually in the 
wheel well area on the aft flange. The problem with visual inspections 
is the access doubler flanges cover a large percentage of the forward 
spar flange. This limits the effectiveness of the visual inspections.
    To meet industry NDI standards, cracks need to be found on Cessna 
Models 401, 401A, 401B, 402, 402A, 402B, 411, and 411A airplanes 
through NDI inspection methods with a 90-percent probability of 
detection at a 95-percent confidence level.
    Cessna's analysis indicates that the probability and confidence 
levels are not being met.

What Are the Consequences if the Condition Is Not Corrected?

    This condition, if not corrected could result in wing spar cap 
failure due to undetected fatigue cracks. Such failure could result in 
loss of a wing with consequent loss of airplane control.

[[Page 57396]]

Has FAA Taken Any Action to This Point?

    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 all 
Models 401, 401A, 401B, 402, 402A, 402B, 411, and 411A airplanes. This 
proposal was published in the Federal Register as a notice of proposed 
rulemaking (NPRM) on May 15, 2003 (68 FR 26239). The NPRM proposed to 
require you to either (depending on the aircraft configuration):
    [sbull] For airplanes that do not incorporate one of certain Cessna 
Service Kits: Repetitively inspect the wing spar caps for fatigue 
cracks and repair or replace the wing spar caps as necessary and 
incorporate a spar strap modification on each wing spar; or
    [sbull] For airplanes that incorporate one of certain Cessna 
Service Kits: Repetitively inspect the wing spar caps for fatigue 
cracks and repair or replace the wing spar caps as necessary.
    You would have to accomplish the proposed actions in accordance 
with Cessna Service Bulletin MEB01-06 and Cessna Service Kit SK402-46, 
both dated September 24, 2001; and Cessna Service Bulletin MEB01-07 and 
Cessna Service Kit SK411-59, both dated September 24, 2001.

Was the Public Invited To Comment?

    The FAA encouraged interested persons to participate in the making 
of this amendment. During the comment period, we received requests to 
extend the comment period. Consequently, we extended the comment period 
from August 8, 2003, to September 8, 2003.
    We have received an additional comment to extend the comment period 
an additional 6 months action in order to allow more time to evaluate 
the impact of the actions of the proposed AD. We have evaluated this 
request and determined the following:
    [sbull] An additional 60 days is a more appropriate time than 6 
months; and
    [sbull] Instead of extending the comment period, we will need to 
reopen the comment period because the comment ending date has passed.

The Supplemental NPRM

The FAA's Determination?

    We have determined that an additional 60 days (total of 150 days) 
is a reasonable time period to allow the public to comment on the 
proposed AD. Therefore, we are issuing a supplemental NPRM and 
reopening the comment period to allow the public additional time to 
comment.

How Does the Revision to 14 CFR Part 39 Affect This Proposed AD?

    On July 10, 2002, FAA 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 special flight 
permits, alternative methods of compliance, and altered products. 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.

Cost Impact

How Many Airplanes Would This Proposed AD Impact?

    We estimate that this proposed AD affects 400 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 the proposed 
modification and initial inspection:

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                                                                                            Total cost on U.S.
              Labor cost                      Parts cost        Total cost per airplane         operators
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485 workhours x $60 per hour =         $1,763 per airplane....  $29,100 + $1,763 =       $30,863 x 400 =
 $29,100 per airplane.                                           $30,863 per airplane.    $12,345,200.
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    The above figures do not take into account the cost of repetitive 
inspections. The FAA does not have any way of determining the number of 
repetitive inspections each owner/operator would incur during the 
operating life of the affected airplanes.

Regulatory Impact

Would This Proposed AD Impact Various Entities?

    The regulations proposed herein 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. Therefore, it 
is determined that this proposed rule would not have federalism 
implications under Executive Order 13132.

Would This Proposed AD Involve a Significant Rule or Regulatory Action?

    For the reasons discussed above, I certify that this proposed 
action (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); and (3) if 
promulgated, 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. A copy of the draft regulatory 
evaluation prepared for this action has been placed in the Rules 
Docket. A copy of it may be obtained by contacting the Rules Docket at 
the location provided under the caption ADDRESSES.

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 
part 39 of the Federal Aviation Regulations (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. FAA amends Sec.  39.13 by removing Airworthiness Directive (AD) 
79-10-15 R2, Amendment 39-3711, and by adding a new AD to read as 
follows:

Cessna Aircraft Company: Docket No. 2002-CE-05-AD; Supersedes AD 79-
10-15 R2, Amendment 39-3711.

    (a) What airplanes are affected by this AD? This AD affects 
Models 401, 401A, 401B, 402, 402A, 402B, 411, and 411A airplanes, 
all serial numbers, that are certificated in any category.
    (b) Who must comply with this AD? Anyone who wishes to operate 
any of the airplanes identified in paragraph (a) of this AD must 
comply with this AD.
    (c) What problem does this AD address? The actions specified by 
this AD are intended to prevent wing spar cap failure due to 
undetected fatigue cracks. Such failure could result in loss of a 
wing with consequent loss of airplane control.

[[Page 57397]]

    (d) What actions must I accomplish to address this problem? To 
address this problem, you must repetitively inspect the wing spar 
caps for fatigue cracks and repair or replace the wing spar caps as 
necessary and incorporate a spar strap modification (as specified) 
on each wing spar in accordance with Cessna Service Bulletin MEB01-6 
and Cessna Service Kit SK402-46, both dated September 24, 2001; or 
Cessna Service Bulletin MEB01-7 and Cessna Service Kit SK411-59, 
both dated September 24, 2001, as follows:

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Initial and repetitive compliance times         Affected airplanes
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(1) Inspect and modify at whichever of   Cessna Models 411 and 411A
 the following that occurs later and      airplanes that do not
 repair or replace as necessary prior     incorporate Cessna Service Kit
 to further flight after the              SK411-56, SK411-56A, or SK411-
 inspection, unless already               56B.
 accomplished, and repetitively inspect
 at the intervals specified in
 paragraphs (d)(3)(i), (d)(3)(ii), and
 (d)(3)(iii) of this AD:
 (i) Upon accumulating 5,500 hours time-
 in-service (TIS) on a wing spar; or
 (ii) Within the next 200 hours TIS
 after the effective date of this AD or
 12 months after the effective date of
 this AD, whichever occurs first
(2) Inspect and modify at whichever of   Cessna Models 401, 401A, 401B,
 the following that occurs first and      402, 402A, and 402B airplanes
 repair or replace as necessary prior     that do not incorporate Cessna
 to further flight after the              Service Kit SK402-36, SK402-
 inspection, unless already               36B, or SK402-36C.
 accomplished, and repetitively inspect
 at the intervals specified in
 paragraphs (d)(4)(i) and (d)(4)(ii) of
 this AD:
 (i) Upon accumulating 6,500 hours TIS
 on a wing spar; or
 (ii) Within the next 200 hours TIS
 after the effective date of this AD or
 12 months after the effective date of
 this AD, whichever occurs first
(3) Inspect in the following areas       Cessna Models 411 and 411A
 (modification not required for these     airplanes that incorporate
 airplanes) and repair or replace as      Cessna Service Kit SK411-56,
 necessary prior to further flight        SK-411-56A, SK411-56B, or
 after the inspection where cracks are    SK411-59. This includes
 found. Inspection areas are defined in   airplanes that had Cessna
 the Cessna Model 411 Supplemental        Service Kit SK411-59
 Inspection Document (SID):               incorporated as required by
 (i) Area ``A'' (Inspection ID 57-10-     paragraph (d)(1) of this AD.
 11): Initially upon accumulating 5,400
 hours TIS after incorporating the
 applicable service kit on a wing spar
 or within the next 100 hours TIS after
 the effective date of this AD,
 whichever occurs later, unless already
 accomplished, and thereafter at
 intervals not to exceed 2,500 hours
 TIS
 (ii) Area ``B'' (Inspection ID 57-10-
 12): Initially upon accumulating 5,400
 hours TIS after incorporating the
 applicable service kit on a wing spar
 or within the next 100 hours TIS after
 the effective date of this AD,
 whichever occurs later, unless already
 accomplished, and thereafter at
 intervals not to exceed 1,000 hours
 TIS
 (iii) Area ``C'' (Inspection ID 57-10-
 08): Upon accumulating 19,900 hours
 TIS after incorporating the applicable
 service kit on a wing spar or within
 the next 100 hours TIS after the
 effective date of this AD, whichever
 occurs later, unless already
 accomplished, and thereafter at
 intervals not to exceed 2,000 hours
 TIS
(4) Inspect in the following areas       Cessna Models 401, 401A, 401B,
 (modification not required for these     402, 402A, and 402B airplanes
 airplanes) and repair or replace as      that incorporate Cessna
 necessary prior to further flight        Service Kit SK402-36, SK402-
 after the inspection. Inspection areas   36A, SK402-36B, SK402-36C, or
 are defined in the Cessna Model 401/     SK402-46. This includes
 402 Supplemental Inspection Document     airplanes that had Cessna
 (SID):                                   Service Kit SK402-46
 (i) Area ``A'' (Inspection ID 57-10-     incorporated as required by
 11) and Area ``B'' (Inspection ID 57-    paragraph (d)(2) of this AD.
 10-12): Initially upon accumulating
 7,400 hours TIS after incorporating
 the applicable service kit on a wing
 spar or within the next 100 hours TIS
 after the effective date of this AD,
 whichever occurs later, unless already
 accomplished, and thereafter at
 intervals not to exceed 5,000 hours
 TIS
 (ii) Area ``C'' (Inspection ID 57-10-
 08): Initially upon accumulating
 19,900 hours TIS after incorporating
 the applicable service kit on a wing
 spar or within the next 100 hours TIS
 after the effective date of this AD,
 whichever occurs later, unless already
 accomplished, and thereafter at
 intervals not to exceed 2,500 hours
 TIS
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    (e) Can I comply with this AD in any other way?
    (1) To use an alternative method of compliance or adjust the 
compliance time, follow the procedures in 14 CFR 39.19. Send these 
requests to the Manager, Wichita Aircraft Certification Office 
(ACO). For information on any already approved alternative methods 
of compliance, contact Paul Nguyen, Aerospace Engineer, FAA, Wichita 
Aircraft Certification Office, 1801 Airport Road, Mid-Continent 
Airport, Wichita, Kansas 67209; telephone: (316) 946-4125; 
facsimile: (316) 946-4107.
    (2) Alternative methods of compliance approved in accordance 
with AD 79-10-15 R2, which is superseded by this AD, are not 
approved as alternative methods of compliance with this AD.
    (f) How do I get copies of the documents referenced in this AD? 
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) 517-5800; facsimile: (316) 942-9006. 
You may view these documents at FAA, Central Region, Office of the 
Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106.
    (g) Does this AD action affect any existing AD actions? This 
amendment supersedes AD 79-10-15 R2, Amendment 39-3711.



[[Page 57398]]


    Issued in Kansas City, Missouri, on September 26, 2003.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 03-25089 Filed 10-2-03; 8:45 am]
BILLING CODE 4910-13-P