Document ID: FAA-2012-0083-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Aeronautical Accessories Inc. High Landing Gear Aft Crosstube Assembly
Posted Date: 2012-02-03T05:00Z

[Federal Register Volume 77, Number 23 (Friday, February 3, 2012)]
[Proposed Rules]
[Pages 5420-5423]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-2423]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0083; Directorate Identifier 2010-SW-022-AD]
RIN 2120-AA64

Airworthiness Directives; Aeronautical Accessories Inc. High 
Landing Gear Aft Crosstube Assembly

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for the 
Aeronautical Accessories Inc. (AAI) High Landing Gear Aft Crosstube 
Assembly (aft crosstube) installed on certain Bell Helicopter Textron, 
Inc. (Bell) and Agusta S.p.A. (Agusta) model helicopters as an approved 
Bell part installed during production or based on a Supplemental Type 
Certificate (STC). This proposed AD is prompted by three reports of 
failed crosstubes because of cracks. The proposed actions are intended 
to prevent failure of a crosstube, collapse of the landing gear, and 
subsequent loss of control of the helicopter.

DATES: We must receive comments on this proposed AD by April 3, 2012.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Docket: Go to http://www.regulations.gov. Follow the online instructions for sending your 
comments electronically.
     Fax: (202) 493-2251.
     Mail: Send comments to the U.S. Department of 
Transportation, Docket Operations, M-30, West Building Ground Floor, 
Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590-0001.
     Hand Delivery: Deliver to the ``Mail'' address between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov or in person at the Docket Operations Office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the economic 
evaluation, any comments received, and other information. The street 
address for the Docket Operations Office (telephone (800) 647-5527) is 
in the ADDRESSES section. Comments will

[[Page 5421]]

be available in the AD docket shortly after receipt.
    For service information identified in this proposed AD, contact 
Aeronautical Accessories, Inc., P.O. Box 3689, Bristol, Tennessee 
37625-3689, telephone (423) 538-5151 or 1-800-251-7094, fax (423) 538-
8469 or at http://www.aero-access.com. You may also get service 
information from Bell Helicopter Textron, Inc., P.O. Box 482, Fort 
Worth, TX 76101, telephone (817) 280-3391, fax (817) 280-6466, or at 
http://www.bellcustomer.com/files. You may review copies of the 
referenced service information at the FAA, Office of the Regional 
Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, TX 
76137.

FOR FURTHER INFORMATION CONTACT: Martin R. Crane, Aviation Safety 
Engineer, Rotorcraft Directorate, Rotorcraft Certification Office, 2601 
Meacham Blvd., Fort Worth, TX 76137, telephone (817) 222-5170, email 
martin.r.crane@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to participate in this rulemaking by submitting 
written comments, data, or views. We also invite comments relating to 
the economic, environmental, energy, or federalism impacts that might 
result from adopting the proposals in this document. The most helpful 
comments reference a specific portion of the proposal, explain the 
reason for any recommended change, and include supporting data. To 
ensure the docket does not contain duplicate comments, commenters 
should send only one copy of written comments, or if comments are filed 
electronically, commenters should submit only one time.
    We will file in the docket all comments that we receive, as well as 
a report summarizing each substantive public contact with FAA personnel 
concerning this proposed rulemaking. Before acting on this proposal, we 
will consider all comments we receive on or before the closing date for 
comments. We will consider comments filed after the comment period has 
closed if it is possible to do so without incurring expense or delay. 
We may change this proposal in light of the comments we receive.

Discussion

    This document proposes adopting a new AD for AAI aft crosstubes 
installed during production or based on STC SR01502AT on certain Bell 
and Agusta model helicopters. This proposal would require certain 
recurring visual, dimensional, and fluorescent penetrant inspections of 
each aft crosstube. If there is a crack, the AD would require, before 
further flight, replacing any cracked aft crosstube with an airworthy 
aft crosstube. This proposal would also require establishing a life 
limit for one of the affected part-numbered aft crosstubes (as the 
later part-numbered aft crosstube already has limits established) and 
creating a component history card or equivalent record for aft 
crosstube part number (P/N) 412-321-304. This proposal is prompted by 
three reports of failed aft crosstubes. This condition, if not 
corrected, could result in collapse of the landing gear, and subsequent 
loss of control of the helicopter.

FAA's Determination

    We are proposing this AD because we evaluated all known relevant 
information and determined that an unsafe condition exists and is 
likely to exist or develop on other products of the same type design.

Related Service Information

    We have reviewed AAI Alert Service Bulletin No. AA-07109, dated 
April 3, 2008 (ASB), which specifies recurring inspections and 
maintenance of each aft crosstube, P/N 412-321-104, installed as an 
approved part by Bell during production, and P/N 412-321-304, installed 
under STC SR01052AT, on Bell Model 412, 412EP, and 412CF and Agusta 
Model AB412 and AB412EP helicopters. The ASB specifies establishing a 
high aft crosstube, P/N 412 321-304, ``takeoff/landing'' life limit of 
20,000. Also, the ASB specifies that operators should follow helicopter 
towing instructions to prevent crosstube damage or failure as a result 
of ground handling or towing.
    We have also reviewed Bell ASB 412-08-129, dated May 12, 2008, for 
Bell Model 412 and 412EP helicopters, serial numbers 33001 through 
33213, 36001 and subsequent, with an aft crosstube P/N 412-321-104 
installed. Bell issued its ASB ``to achieve complete distribution of 
AA-07109 vendor bulletin to the current affected model distribution 
list.''

Proposed AD Requirements

    This proposed AD would require:
     Within 50 hours time-in-service (TIS), establishing a life 
limit of 20,000 takeoffs and landings for aft crosstube P/N 412 321 
304; creating a component history card or equivalent record; and 
determining and recording the total number of takeoffs and landings for 
each aft crosstube.
     Within the next 450 takeoffs and landings, if an aft 
crosstube has reached 20,000 or more takeoffs and landings, replacing 
it with an airworthy aft crosstube.
     At specified intervals, preparing the aft crosstube 
inspection areas and inspecting each aft crosstube for a crack. If 
there are no cracks, thereafter at specified intervals, priming and 
cleaning the inspection area, and inspecting each aft crosstube for a 
crack. If there is a crack, before further flight, replacing the 
cracked aft crosstube with an airworthy aft crosstube.
     At specified intervals, determining the horizontal 
deflection of each aft crosstube from the centerline of the helicopter 
(BL 0.0) to the outside of the skid tubes. If the measured horizontal 
deflection exceeds aft crosstube limits, replacing the aft crosstube 
with an airworthy aft crosstube.
     At specified intervals, removing the aft crosstube 
assembly, removing paint and sealant, and fluorescent penetrant 
inspecting each aft crosstube for a crack. If there are no cracks, 
priming and painting the inspection area. If there is a crack, before 
further flight, replacing each cracked aft crosstube with an airworthy 
aft crosstube.
    This proposed AD would revise the Airworthiness Limitations section 
of the applicable maintenance manuals or the Instructions for Continued 
Airworthiness (ICA) by establishing a new retirement life of 20,000 
takeoffs and landings for aft crosstube P/N 412-321-304 by making pen 
and ink changes or inserting a copy of the AD into the maintenance 
manual or the ICAs.

Costs of Compliance

    We estimate that this proposed AD would affect 115 helicopters of 
U.S. Registry.
    We also estimate that the proposed actions would take about:
     1 hour to create a component history card or equivalent 
record and determine and record the number of accumulated takeoffs and 
landings for each affected aft crosstube;
     3 hours to prepare the area for a visual inspection;
     \1/2\ hour to do the repetitive visual inspections, 
assuming 14 repetitive visual inspections per year;
     1 hour to do a dimensional inspection of the skid gear, 
assuming 3 inspections per year;
     24 hours to prepare and fluorescent penetrant inspect the 
aft crosstube, assuming 2 inspections per year; and
     10 hours to replace an aft crosstube, if necessary, 
assuming 3 aft crosstubes would be replaced.
    The average labor rate is $85 per work hour. Required parts would 
cost about $9,315 per aft crosstube. Based on these

[[Page 5422]]

figures, we estimate the total cost impact of the proposed AD on U.S. 
operators to be $636,545.

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 
rulemaking action.

Regulatory Findings

    We 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, I certify this 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);
    3. Will not affect intrastate aviation in Alaska to the extent that 
it justifies making a regulatory distinction; and
    4. 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 an economic evaluation of the estimated costs to comply 
with this proposed AD and placed it in the AD docket.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, 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:

Aeronautical Accessories, Inc.: Docket No. FAA-2012-0083; 
Directorate Identifier 2010-SW-022-AD.

(a) Applicability

    This AD applies to High Landing Gear Aft Crosstube Assembly (aft 
crosstube) part number (P/N) 412-321-104 and P/N 412-321-304, 
installed on Agusta S.p.A. Model AB412 and AB412EP and Bell 
Helicopter Textron, Inc., Model 412, 412CF, and 412EP helicopters, 
certificated in any category.

(b) Unsafe Condition

    This AD defines the unsafe condition as a cracked aft crosstube 
which could result in collapse of the landing gear, and subsequent 
loss of control of the helicopter.

(c) Compliance

    You are responsible for performing each action required by this 
AD within the specified compliance time unless it has already been 
accomplished prior to that time.

(d) Required Actions

    (1) Within 50 hours time-in-service (TIS) establish a life limit 
of 20,000 takeoffs and landings for each aft crosstube P/N 412-321-
304. For the purposes of this AD, a takeoff and landing is defined 
as the cycle from when the helicopter gets light on the skids 
(takeoff) unloading the aft crosstube and then settles on the skids 
again (landing) reloading the aft crosstubes. Either the number of 
landings or takeoffs may be counted.
    (i) Create a component history card or equivalent record.
    (ii) Determine and record on the history card or equivalent 
record the total number of takeoffs and landings for each aft 
crosstube. If the takeoff and landing information is unavailable, 
estimate the number by multiplying the airframe hours by 10.
    (2) Within the next 450 takeoffs and landings, if an aft 
crosstube has reached 20,000 or more takeoffs and landings, replace 
it with an airworthy aft crosstube.
    (3) Before reaching 2,500 takeoffs and landings or for an aft 
crosstube with 2,500 or more takeoffs and landings, within 50 hours 
TIS or within the next 250 takeoffs and landings, whichever occurs 
first, prepare the aft crosstube inspection areas as depicted in 
Figure 1 of Aeronautical Accessories, Inc. (AAI) Alert Service 
Bulletin No. AA-07109, dated April 3, 2008 (ASB), by following the 
Accomplishment Instructions, Part B, paragraphs 1 through 4, of the 
ASB. Using a 10X or higher magnifying glass, inspect the prepared 
areas of each aft crosstube for a crack. If there is a crack, before 
further flight, replace the cracked aft crosstube with an airworthy 
aft crosstube. If there are no cracks, after completing the aft 
crosstube inspection, prime and paint the inspection area by 
following the Accomplishment Instructions, Part B, paragraphs 6 and 
7, of the ASB.
    (4) Thereafter, at intervals not to exceed 450 takeoffs and 
landings, clean the inspection area. Using a 10X or higher 
magnifying glass, inspect the clear-coated area of the aft crosstube 
for a crack.
    (5) If there is a crack, before further flight, replace the 
cracked aft crosstube with an airworthy aft crosstube.
    (6) Within 30 days or before reaching 2,500 takeoffs and 
landings, whichever occurs later, and thereafter at intervals not to 
exceed 2,500 takeoffs and landings or 12 months, whichever occurs 
first, determine the horizontal deflection of each aft crosstube 
from the centerline of the helicopter (BL 0.0) to the outside of the 
skid tubes by following the Accomplishment Instructions, Part D, 
paragraphs 1 through 3, of the ASB. If the measured aft crosstube 
horizontal deflection depicted in Figure 2 of the ASB is less than 
57 inches (1448 mm) or greater than 59 inches (1499 mm), replace the 
aft crosstube with an airworthy aft crosstube.
    (7) Within 3 months or on or before reaching 7,500 takeoffs and 
landings, whichever occurs later, and thereafter at intervals not to 
exceed 5,000 takeoffs and landings:
    (i) Remove the aft crosstube assembly by removing the aft 
crosstube support beam assembly, P/N 604-030-001, and both aft 
crosstube clamp assemblies, P/N 604-027-002.
    (ii) Remove paint and sealant from the aft crosstube outboard of 
the upper center support to top of saddles, both sides, as depicted 
in Figure 3 of the ASB.
    (iii) Fluorescent penetrant inspect each aft crosstube outboard 
of the upper center support as depicted in Figure 3 of the ASB for a 
crack.
    (iv) If there is a crack, before further flight, replace the 
cracked aft crosstube with an airworthy aft crosstube.
    (8) Revise the helicopter Airworthiness Limitations section of 
the applicable maintenance manuals or the Instructions for Continued 
Airworthiness (ICA) by establishing a new retirement life of 20,000 
takeoff and landings for aft crosstube P/N 412-321-304 by making pen 
and ink changes or inserting a copy of this AD into the maintenance 
manual or the ICAs.

(e) Alternative Methods of Compliance (AMOC)

    (1) The Manager, Rotorcraft Certification Office, FAA, may 
approve AMOCs for this AD. Send your proposal to: Martin R. Crane, 
Aviation Safety Engineer, Rotorcraft Directorate, Rotorcraft 
Certification Office, 2601 Meacham Blvd., Fort Worth, Texas 76137, 
telephone (817) 222-5170, email martin.r.crane@faa.gov.
    (2) For operations conducted under a Part 119 operating 
certificate or under Part 91, Subpart K, we suggest that you notify 
your principal inspector, or lacking a principal inspector, the 
manager of the local flight standards district office or certificate 
holding district office before operating any aircraft complying with 
this AD through an AMOC.

[[Page 5423]]

(f) Additional Information

    The FAA approved AAI Instructions for Continued Airworthiness 
Report Number AA-01136 and the Bell Helicopter Textron Alert Service 
Bulletin No. 412-08-129, dated May 12, 2008, which are not 
incorporated by reference, contain additional information about 
inspecting the aft crosstube for a crack.

(g) Subject

    Joint Aircraft Service Component (JASC) Code: 32: Landing Gear.

    Issued in Fort Worth, Texas, on January 23, 2012.
Kim Smith,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2012-2423 Filed 2-2-12; 8:45 am]
BILLING CODE 4910-13-P