DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0415; Directorate Identifier 2008-SW-065-AD]
RIN 2120-AA64

Airworthiness Directives; Bell Helicopter Textron, Incorporated Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to supersede an existing airworthiness directive
(AD) for Bell Helicopter Textron, Inc. (BHTI) Model 204B, 205A, 205A-1,
205B, and 212 helicopters. The existing AD currently requires
conducting various inspections associated with the main rotor grip
(grip). If a crack is found, that AD requires replacing the grip before
further flight. If delamination of the buffer pad on the grip tang
inner surface is found, that AD requires inspecting the grip surface
for corrosion or other damage and repairing or replacing the grip if
corrosion or other damage is found. That AD also requires determining
and recording the hours time-in-service (TIS) and the engine start/stop
cycles for each grip on a component history card or equivalent record.
Additionally, that AD requires you to report certain inspection results
to the FAA. Since we issued that AD, additional cracks in grips have
been found. Analysis of these events has shown that a retirement life
is needed for certain grips, and the AD
applicability needs to be expanded to include additional grips similar
in design, as well as to include the Model 210 helicopter, which was
issued an FAA type certificate after the existing AD was issued. The
proposed actions are intended to prevent failure of a grip, separation
of a main rotor blade, and subsequent loss of control of the helicopter.

DATES: We must receive comments on this proposed AD by June 19, 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 be available in the AD
docket shortly after receipt.

For service information identified in this proposed AD, contact
BHTI, 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 service information at the FAA, Office of the Regional
Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth,
Texas 76137.

FOR FURTHER INFORMATION CONTACT: Michael Kohner, Aviation Safety
Engineer, Rotorcraft Certification Office, 2601 Meacham Blvd., Fort
Worth, Texas 76137, telephone (817) 222-5170, fax (817) 222-5783, email
mike.kohner@faa.gov or 7-avs-asw-170@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

On December 31, 2002, we issued AD 2003-01-04, Amendment 39-13015
(68 FR 1955, January 15, 2003), for the BHTI Model 204B, 205A, 205A-1,
205B, and 212 helicopters. That AD requires the following actions:

Within 10 hours TIS, determining and recording the hours
TIS and the engine start/stop cycles for each grip on a component
history card or equivalent record. On the single-engine model
helicopters, one "engine start/stop cycle" occurs when the engine is
started. On the Model 212 helicopter, one "engine start/stop cycle"
occurs when either one or both engines are started. The intent is to
add one "engine start/stop cycle" each time helicopter power starts
the main rotor system turning.

Within 10 hours TIS and thereafter at intervals not to
exceed 25 hours TIS, visually inspecting the exposed surfaces of the
upper and lower tangs of each grip for a crack, using a 10-power or
higher magnifying glass.

At specified intervals, depending on the hours TIS or the
engine start/stop cycles, whichever occurs first, conducting initial
and repetitive ultrasonic (UT) inspections of each grip in accordance
with the Nondestructive Inspection Procedure, Log No. 00-340, Revision
E, dated April 9, 2002.

At intervals not to exceed 1,200 hours TIS or 24 months,
whichever occurs first, inspecting each buffer pad on the tang inner
surfaces for delamination and removing the buffer pad and inspecting
the grip surface for corrosion and other damage if delamination is
found.

Within 2,400 hours TIS or at the next overhaul of the main
rotor hub, whichever occurs first, and thereafter at intervals not to
exceed 2,400 hours TIS, inspecting the surface of each affected grip
for corrosion or other damage and conducting a fluorescent-penetrant
inspection (FPI) of the grip for a crack.

Before further flight, replacing any grip that has a
crack, corrosion, or other damage with an airworthy grip, or repairing
a grip with corrosion or other damage if the corrosion or other damage
is within certain limits.

Reporting certain inspection results and information to
the FAA in accordance with Appendix 1 of the AD.

AD 2003-01-04 was prompted by three in-flight grip failures and two
cracked grips discovered during a 1,200-hour TIS inspection and on a
scheduled 2,400-hour TIS overhaul, which brought the total to 13 grips
that had cracked in the lower tang. No anomalies or damage to the
blade, blade bolt bore, or buffer pad tang surface were found in the
two cracked grips found during the inspection and overhaul. Cracking on
all of the grips has been attributed to mechanical damage from improper
blade bolt bushing installation, improper rework of the buffer pad tang
surface, or subsurface fatigue damage. All of the fatigue cracks
occurred on grip part numbers (P/N) 204-011-121-009 and -121, installed
on BHTI Model 212 helicopters. Grip P/Ns 204-011-121-005, -113, and -
117, installed on BHTI Model 204B, 205A, 205A-1, and 205B helicopters,
were also included because the grips are very similar in design and are
subjected to the same forces and loads as the grips installed on BHTI
Model 212 helicopters. We issued that AD to prevent failure of a grip,
separation of a main rotor blade, and subsequent loss of control of the
helicopter.

Actions Since Existing AD Was Issued

Since issuing the existing AD, small cracks in three grips,
initiating in the blade bolt bore, have been detected during UT
inspections. Additionally, one crack in another grip was discovered
visually, another crack was found after an in-flight vibration
developed, and one grip fractured during flight. This brings the total
to 19 grips that have cracked in the lower tang. Based on these
additional discoveries of cracked grips and subsequent analyses
performed by the manufacturer, we have determined the following:

The applicability of the AD needs to be expanded to
include replacement grip P/N ASI-4011-121-9, produced under a part
manufacturing approval (PMA) issued by the FAA, because the design
approval for this grip was based on its design being identical to the
original BHTI-manufactured grip, P/N 204-011-121-009;

The applicability of the AD needs to be expanded to
include any Model 204B, 205A, 205A-1, and 212 helicopters with grip P/N
204-011-121-009, -121, or ASI-4011-121-9 installed;

The applicability of the AD needs to be expanded to
include the Model 210 helicopter, which has a grip P/N 204-011-121-009
and -121, installed. This model was not included in AD 2003-01-04
because the FAA issued the BHTI Model 210 type certificate after AD
2003-01-04 was issued;

A retirement life is needed for grip P/Ns 204-011-121-009,
204-011-121-121, and ASI-4011-121-9. These grips, installed on Model
205B, 210, and 212 helicopters, are currently unlimited in service life
and are only required to be replaced when damaged or corroded beyond
repair. Early failures of these grips, which have not been attributed
to mechanical damage, have indicated a need to establish retirement
lives to avoid possible cracking in the future;

The procedure for calculating the total hours TIS for any
grip where the hours TIS cannot be determined from the helicopter
records should be modified to more accurately account for the actual
usage of the fleet and clarify the intent of the AD; and

The reporting of inspection findings to the FAA is no longer needed.

FAA's Determination

We are proposing this AD because we evaluated all the relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other helicopters of these same type designs.

Related Service Information

We reviewed the following BHTI service information:

Operations Safety Notices 204-85-6, 205-85-9, and 212-85-
13, all dated November 14, 1985, which describe a grip with a crack in
the lower tang that was returned by an operator;

Alert Service Bulletin (ASB) No. 212-94-92, Revision A,
dated March 13, 1995, which describes procedures for inspection and
overhaul requirements of certain grips;

ASB No. 204-02-58, dated November 26, 2002; ASB No. 205-
02-88, dated November 26, 2002; and ASB No. 210-08-02, dated September
10, 2008. These ASBs specify a UT inspection of certain grips;

ASB No. 205B-02-39, Revision B, dated November 22, 2002
and ASB No. 212-02-116, Revision A, dated October 30, 2002, which
specify a UT inspection of certain grips and include the Nondestructive
Inspection Procedure, Log No. 00-340, Revision E, dated April 9, 2002;
and

Information Letter 204-08-23, 205-08-38, 205B-08-21, and
212-08-62, Revision A, dated July 23, 2008 (one letter issued with 4
identification numbers), which describes a new, improved replacement
grip, P/N 204-011-121-125, that would not require the repetitive UT
inspections and would have a retirement life of 25,000 hours TIS or a
500,000 Retirement Index Number (RIN), whichever comes first.

Proposed AD Requirements

This proposed AD would retain certain requirements of AD 2003-01-
04, and would require additional actions. The proposed requirements are
as follows:

Within 10 hours TIS, determining and recording the hours
TIS and the engine start/stop cycles for each grip on a component
history card or equivalent record. For each month that the hours TIS
cannot be determined, this proposed AD would assume 50 hours TIS.

Within 10 hours TIS and thereafter at intervals not to
exceed 25 hours TIS, visually inspecting the exposed surfaces of the
upper and lower tangs of each grip for a crack, using a 10-power or
higher magnifying glass.

At specified intervals, depending on the hours TIS or the
engine start/stop cycles, whichever occurs first, conducting initial
and repetitive UT inspections of each grip, in accordance with the
Nondestructive Inspection Procedure, Log No. 00-340, Revision E, dated
April 9, 2002.

At intervals not to exceed 1,200 hours TIS or 24 months,
whichever occurs first, inspecting each buffer pad on the tang inner
surfaces for delamination, and removing the buffer pad and inspecting
the grip surface for corrosion and other damage if delamination is
found.

Within 2,400 hours TIS or at the next overhaul of the main
rotor hub, whichever occurs first, and thereafter at intervals not to
exceed 2,400 hours TIS, inspecting the surface of each affected grip
for corrosion or other damage and conducting an FPI of the grip for a
crack.

Before further flight, replacing any grip that has a
crack, corrosion, or other damage with an airworthy grip, or repairing
a grip with corrosion or other damage if the corrosion or other damage
is within certain limits.

Before further flight, removing any grip, P/N 204-011-121-
009 or ASI-4011-121-9, that has 15,000 or more hours TIS;

Before further flight, removing any grip, P/N 204-011-121-
121, that has 25,000 or more hours TIS;

Revising the Airworthiness Limitations sections of the
applicable maintenance manuals or the Instructions for Continued
Airworthiness by establishing a new retirement life of 15,000 hours TIS
for grip, P/N 204-011-121-009 or ASI-4011-121-9, and 25,000 hours TIS
for grip, P/N 204-011-121-121; and

Recording the applicable hours TIS life limits for grips,
P/N 204-011-121-009, ASI-4011-121-9, and 204-011-121 on the applicable
component history card or equivalent record.

Differences Between the Proposed AD and the Service Information

This proposed AD requires life limits for grips, P/N 204-011-121-
009, 204-011-121-121, and ASI-4011-121-9. The manufacturer's service
bulletins do not specify a service life for these grips. Also, this
proposed AD applies to grip P/N ASI-4011-121-9, which is produced under
a parts manufacturing approval, and the manufacturer's service
bulletins do not address this particular grip.

Costs of Compliance

We estimate that this proposed AD would affect 700 helicopters of
U.S. registry, and it would take approximately 7 work hours to create
and maintain the records, 6.25 work hours to conduct the inspections,
and 20 work hours to replace a set of grips at an average labor rate of
$85 per work hour. Required parts would cost approximately $56,385 for
a replacement set of grips. Based on these figures, we estimate the
total cost impact of the proposed AD on U.S. operators to be $6,596,875
for the entire fleet, assuming the grip set (2 grips) must be replaced
on 100 helicopters.

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 helicopters
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 removing Amendment 39-13015 (68 FR
1955, January 15, 2003), and adding the following new airworthiness
directive (AD):