[Federal Register Volume 70, Number 34 (Tuesday, February 22, 2005)]
[Proposed Rules]
[Pages 8549-8551]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-3271]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2004-20007; Directorate Identifier 2004-CE-50-AD]
RIN 2120-AA64


Airworthiness Directives; Air Tractor Inc. Model AT-602 Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for all Air Tractor Inc. Model AT-602 airplanes. This proposed AD would 
require you to repetitively inspect (using the eddy current methods) 
the two outboard holes in the lower wing spar caps for cracks and 
repair or replace any cracked spar cap. This proposed AD results from 
fatigue cracking of the wing main spar lower cap at the centerline 
joint outboard fastener hole. We are issuing this proposed AD to detect 
and correct cracks in the wing main spar lower cap, which could result 
in failure of the spar cap and lead to wing separation and loss of 
control of the airplane.

DATES: We must receive any comments on this proposed AD by April 21, 
2005.

ADDRESSES: Use one of the following to submit comments on this proposed 
AD:
     DOT Docket Web Site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide Rulemaking Web Site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590-001.
     Fax: 1-202-493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    To get the service information identified in this proposed AD, 
contact Air Tractor Inc.; P.O. Box 485, Olney, Texas 76374; telephone: 
(800) 893-1420; facsimile: (701) 572-2602.
    To view the comments to this proposed AD, go to http://dms.dot.gov. 
The docket number is FAA-2004-20007.

FOR FURTHER INFORMATION CONTACT: Andrew McAnaul, Aerospace Engineer, 
ASW-150 (c/o MIDO-43), 10100 Reunion Place, Suite 650, San Antonio, 
Texas 78216; telephone: (210) 308-3365; facsimile: (210) 308-3370.

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 the 
docket number, ``FAA-2004-20007; Directorate Identifier 2004-CE-50-AD'' 
at the beginning of your comments. We will post all comments we 
receive, without change, to http://dms.dot.gov, including any personal 
information you provide. We will also post a report summarizing each 
substantive verbal contact with FAA personnel concerning this proposed 
rulemaking. Using the search function of our docket Web site, anyone 
can find and read the comments received into any of our dockets, 
including the name of the individual who sent the comment (or signed 
the comment on behalf of an association, business, labor union, etc.). 
This is docket number FAA-2004-20007. You may review the DOT's complete 
Privacy Act Statement in the Federal Register published on April 11, 
2000 (65 FR 19477-78) or you may visit http://dms.dot.gov.
    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.

Docket Information

    Where can I go to view the docket information? You may view the AD 
docket that contains the proposal, any comments received, and any final 
disposition in person at the DMS Docket Offices between 9 a.m. and 5 
p.m. (eastern standard time), Monday through Friday, except Federal 
holidays. The Docket Office (telephone 1-800-647-5227) is located on 
the plaza level of the Department of Transportation NASSIF Building at 
the street address stated in ADDRESSES. You may also view the AD docket 
on the Internet at http://dms.dot.gov. The comments will be available 
in the AD docket shortly after the DMS receives them.

Discussion

    What events have caused this proposed AD? The FAA received a report 
of fatigue cracking of the wing main spar lower cap at the centerline 
outboard fastener hole on one Air Tractor Model AT-602 airplane. The 
airplane had 2,895 hours time-in-service at the time the cracking was 
discovered. The fatigue cracking was similar to that found on Air 
Tractor Models AT-502, AT-502A, and AT-502B airplanes. The FAA 
previously issued AD 2002-26-05, Amendment 39-12991 (68 FR 18, January 
2, 2003), to address the condition on the Models AT-502, AT-502A, and 
AT-502B airplanes.

[[Page 8550]]

    What is the potential impact if FAA took no action? Cracks in the 
wing main spar lower cap could result in failure of the spar cap and 
lead to wing separation and loss of control of the airplane.
    Is there service information that applies to this subject? Snow 
Engineering Co. has issued Process Specification 197, revised 
June 4, 2002; Process Specification 205, dated April 26, 2004; 
Service Letter 204, dated November 13, 2003; Service Letter 
240, dated September 30, 2004; and Drawing 20998, Revision B, 
dated September 28, 2004.
    What are the provisions of this service information? The service 
letters, process specifications, and drawing include procedures for:

--Preparing the airplane and the eddy current machine for inspection of 
the lower wing spar caps;
--Inspecting the lower wing spar caps for cracks;
--Verifying suspected cracks for steel and aluminum lower wing spars 
caps;
--Repairing the cracks by installing a web plate and 8-bolt splice 
block; and
--Replacing the spar caps and associated hardware.

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. For this reason, we are 
proposing AD action.
    What would this proposed AD require? This proposed AD would require 
you to incorporate the actions in the previously-referenced service 
information.
    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 107 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 inspection:

----------------------------------------------------------------------------------------------------------------
                                                                                                  Total cost  on
                           Labor cost                               Parts cost      Total  cost        U.S.
                                                                                   per  airplane     operators
----------------------------------------------------------------------------------------------------------------
2 workhours x $65 = $130........................................            N/A            $130         $13,910
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to accomplish any necessary repairs 
that would be required based on the results of this proposed 
inspection. We have no way of determining the number of airplanes that 
may need this repair/replacement:

------------------------------------------------------------------------
                                                             Total  cost
                  Labor cost                    Parts  cost      per
                                                               airplane
------------------------------------------------------------------------
* Install access panels: 22 workhours x $65            $425       $1,855
 per hour = $1,430............................
** Install web plate, 8-bolt splice blocks,           5,000      13,450
 and cold work fastener holes: 130 workhours x
 $65 = $8,450.................................
------------------------------------------------------------------------
*Access panels are incorporated into production starting with serial
  number 602-0670.
**If 8-bolt attach blocks (part number 20985-1/-2) are not installed
  with a web plate, then reduce the cost by $900.

Authority for This Rulemaking

    What authority does FAA have for issuing this rulemaking action? 
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

    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 FAA-2004-20007; Directorate Identifier 2004-CE-50-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:

[[Page 8551]]

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):

Air Tractor Inc.: Docket No. FAA-2004-20007; Directorate Identifier 
2004-CE-50-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 21, 2005.

What Other ADs Are Affected by This Action?

    (b) None.

What Airplanes Are Affected by This AD?

    (c) This AD affects Model AT-602 airplanes, all serial numbers 
beginning with 602-0337, that are certificated in any category.

What Is the Unsafe Condition Presented in This AD?

    (d) This AD is the result of fatigue cracking of the wing main 
spar lower cap at the centerline splice joint outboard fastener 
hole. The actions specified in this AD are intended to detect and 
correct cracks in the wing main spar lower cap, which could result 
in failure of the spar cap and lead to wing separation and loss of 
control of the airplane.

What Must I Do To Address This Problem?

    (e) At the initial inspection time specified in paragraph (e)(2) 
or (e)(3) of this AD, do the following:
    (1) For all affected airplanes, gain access for the required 
inspection listed below by installing cover plates. Follow Snow 
Engineering Co. Service Letter 204 (page 3), dated November 
13, 2003.
    (2) For all affected airplanes not having cold-worked fastener 
holes as described in Snow Engineering Co. Service Letter 
240, dated September 30, 2004; or Process Specification 
205, dated April 26, 2004: Eddy current inspect the two 
outboard holes in both the right and left lower wing spar caps 
following Snow Engineering Co. Process Specification 197, 
revised June 4, 2002. For these non cold-worked airplanes, use the 
following wing spar lower cap hours time-in-service (TIS) schedule 
to do the initial and repetitive inspections:

----------------------------------------------------------------------------------------------------------------
                                                               Initially inspect
                                                             upon accumulating the
                                                              following or within       Repetitively inspect
            Serial Nos.                     Condition          50 hours TIS after    thereafter at the intervals
                                                             the effective date of           following:
                                                               this AD, whichever
                                                                 occurs later:
----------------------------------------------------------------------------------------------------------------
(i) 602-0337 through 602-0584......  As manufactured.......  2,500 hours TIS......  1,000 hours TIS.
(ii) 602-0337 through 602-0584.....  When modified by        2,500 hours TIS......  1,600 hours TIS.
                                      installing Web Plate,
                                      part number (P/N)
                                      20996-2, following
                                      Drawing Number 20998
                                      or 20776, Sheet 2.
(iii) 602-0585 through 602-0694....  As manufactured.......  2,500 hours TIS......  1,600 hours TIS.
----------------------------------------------------------------------------------------------------------------

    (3) For all affected airplanes that have cold-worked fastener 
holes by either Snow Engineering Co. Service Letter 240, 
dated September 30, 2004; or Snow Engineering Co. Process 
Specification 205, dated April 26, 2004: Upon accumulating 
5,000 hours TIS after cold-working the lower spar caps or within 50 
hours TIS after the effective date of the AD, whichever occurs 
later, perform a one-time eddy current inspection of the two 
outboard holes in both the right and left lower wing spar caps 
following Snow Engineering Co. Process Specification 197, 
revised June 4, 2002.
    (4) For all serial number airplanes beginning with 602-0695 
(excludes 602-0337 through 602-0694), upon accumulating 5,000 hours 
TIS on the lower spar caps or within 50 hours TIS after the 
effective date of the AD, whichever occurs later, perform a one-time 
eddy current inspection of the two outboard holes in both the right 
and left lower wing spar caps following Snow Engineering Co. Process 
Specification 197, revised June 4, 2002.
    (5) One of the following must do the inspection:
    (i) A level 2 or 3 inspector certified in eddy current 
inspection using the guidelines established by the American Society 
for Nondestructive Testing or MIL-STD-410; or
    (ii) A person authorized to perform AD work and who has 
completed and passed the Air Tractor, Inc. training course on Eddy 
Current Inspection on wing lower spar caps.
    (f) For all affected airplanes, repair or replace any cracked 
spar cap prior to further flight. For repair or replacement, do one 
of the following:
    (1) Repair small cracks by reaming the cracked hole to the next 
larger size and installing P/N 20985-1 and 20985-2 extended 8-bolt 
splice blocks (and P/N 20996-2 web plate if not already installed) 
following Snow Engineering Co. drawing 20998.
    (2) For large cracks or cracks that can not be removed with the 
8-bolt splice blocks, replace the lower spar caps, splice blocks and 
hardware, and wing attach angles and hardware following Snow 
Engineering Co. drawing 20776, Sheet 2.
    (g) For all affected airplanes, upon accumulating 6,500 hours 
TIS on the wing spar lower caps or within the next 50 hours TIS 
after the effective date of this AD, whichever occurs later, replace 
the wing lower spar caps, splice blocks and hardware, and wing 
attach angles and hardware. Follow Snow Engineering Co. Drawing 
20776, Sheet 2.
    (h) Report any cracks you find within 10 days after the cracks 
are found or within 10 days after the effective date of this AD, 
whichever occurs later. Include in your report the aircraft serial 
number, aircraft TIS, wing spar cap TIS, crack location and size, 
corrective action taken, and a point of contact name and phone 
number. Send your report to Andrew McAnaul, Aerospace Engineer, ASW-
150 (c/o MIDO-43), 10100 Reunion Place, Suite 650, San Antonio, 
Texas 78216; telephone: (210) 308-3365; facsimile: (210) 308-3370.

May I Request an Alternative Method of Compliance?

    (i) 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, Fort Worth Airplane 
Certification Office, FAA, 2601 Meacham Boulevard, Fort Worth, Texas 
76193-0150. For information on any already approved alternative 
methods of compliance, contact Andrew McAnaul, Aerospace Engineer, 
ASW-150 (c/o MIDO-43), 10100 Reunion Place, Suite 650, San Antonio, 
Texas 78216; telephone: (210) 308-3365; facsimile: (210) 308-3370.

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

    (j) To get copies of the documents referenced in this AD, 
contact Air Tractor Inc., P.O. Box 485, Olney, Texas 76374; 
telephone: (800) 893-1420; facsimile: (701) 572-2602. To view the AD 
docket, go to the Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-
401, Washington, DC, or on the Internet at http://dms.dot.gov. The 
docket number is FAA-2004-20007.

    Issued in Kansas City, Missouri, on February 11, 2005.
Nancy C. Lane,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-3271 Filed 2-18-05; 8:45 am]
BILLING CODE 4910-13-P