DEPARTMENT OF TRANSPORTATION

FEDERAL AVIATION ADMINISTRATION

14 CFR Part 39

[Docket No. FAA-2008-0450; Directorate Identifier 2007-SW-39-AD]
RIN 2120-AA64

AIRWORTHINESS DIRECTIVES; Bell Helicopter Textron Canada (BHTC)
Model 230 Helicopters

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 BHTC
Model 230 helicopters. This proposed AD results from mandatory  continuing
airworthiness information  (MCAI) originated  by an  aviation authority of
another country to identify and correct an unsafe condition on an aviation
product. The aviation authority of Canada, with which we have a  bilateral
agreement, states in the MCAI:

It has been determined that  the existing rigging procedures for  the tail
rotor pitch  change mechanism  have to  be changed  due to  possibility of
parts interference.

The cumulative effect of individual part tolerances resulting in the total
assemblage of those parts being out of tolerance could result in the  tail
rotor  yoke  striking  another part  other than  the flapping  stop (parts
interference) as  cited in  the MCAI.  Also, the  misalignment of the tail
rotor counterweight bellcrank may result in higher tail rotor pedal forces
and a higher pilot workload after  failure of the No. 1 hydraulic  system.
Both parts interference and the misaligned counterweight bellcrank  create
an  unsafe  condition. The  proposed  AD would  require  actions that  are
intended to address these unsafe conditions.

DATES: We must receive comments on this proposed AD by May 23, 2008.

ADDRESSES: You may send comments by any of the following methods:

Federal eRulemaking Portal: Go to http:// www.regulations.gov. Follow  the
instructions for submitting comments.

Fax: 202-493-2251.

Mail: U.S.  Department of  Transportation, Docket  Operations, M-30,  West
Building  Ground  Floor,  Room  W12-140,  1200  New  Jersey  Avenue,  SE.,
Washington, DC 20590.

Hand Delivery: U.S. Department of Transportation, Docket Operations, M-30,
West Building  Ground Floor,  Room W12-140,  1200 New  Jersey Avenue, SE.,
Washington, DC 20590,  between 9 a.m.  and 5 p.m.,  Monday through Friday,
except Federal holidays.

You may get  the service information  identified in this  proposed AD from
Bell Helicopter Textron  Canada, 12,800 Rue  de l'Avenir, Mirabel,  Quebec
J7J1R4, telephone (450) 437-2862 or (800) 363-8023, fax (450) 433-0272.

Examining the 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 FURTHER INFORMATION CONTACT: Tyrone Millard, Aviation Safety Engineer,
FAA, Rotorcraft Directorate, Rotorcraft Standards Staff, Fort Worth, Texas
76193-0111, telephone (817) 222-5439, fax (817) 222-5961.

SUPPLEMENTARY INFORMATION:

STREAMLINED ISSUANCE OF AD

The FAA is implementing a new process for streamlining the issuance of ADs
related to  MCAI. This  streamlined process  will allow  us to  adopt MCAI
safety requirements  in a  more efficient  manner and  will reduce  safety
risks to the public. This process continues to follow all FAA AD  issuance
processes  to  meet  legal, economic,  Administrative  Procedure  Act, and
Federal  Register requirements.  We also  continue to  meet our  technical
decision-making responsibilities to identify and correct unsafe conditions
on U.S.-certificated helicopters.

This proposed AD references the MCAI and related service information  that
we  considered in  forming  the  engineering basis  to correct  the unsafe
condition. The proposed AD contains text copied from the MCAI and for this
reason might not follow our plain language principles.

COMMENTS INVITED

We invite you to send any written relevant data, views, or arguments about
this  proposed AD.  Send  your  comments to  an address  listed under  the
ADDRESSES  section.   Include  "Docket   No.  FAA-2008-0450;   Directorate
Identifier  2007-SW-39-AD"   at  the   beginning  of   your  comments.  We
specifically  invite  comments   on  the  overall   regulatory,  economic,
environmental, and energy  aspects of this  proposed AD. We  will consider
all comments received by the closing  date and may amend this proposed  AD
based on those comments.

We  will  post  all  comments  we  receive,  without  change,  to  http://
www.regulations.gov, including  any personal  information you  provide. We
will also  post a  report summarizing  each substantive  verbal contact we
receive about this proposed AD.

DISCUSSION

Transport Canada, which is the  aviation authority for Canada, has  issued
Canadian  Airworthiness  Directive  CF-2007-12,  dated  August  24,   2007
(referred to after this as "the MCAI"), to correct an unsafe condition for
this Canadian-certificated product. The MCAI states:

It has been determined that  the existing rigging procedures for  the tail
rotor pitch  change mechanism  have to  be changed  due to  possibility of
parts interference.

Because the cumulative effect of  the tolerances on the various  parts may
result in  the total  assemblage outboard  of the  counterweight bellcrank
being out of tolerance, the tail  rotor yoke may contact the nut,  P/N 222
-012-731-001, before contacting the flapping stop, resulting in less  tail
rotor travel. Additionally, the  manufacturer has indicated that  the tail
rotor counterweight bellcranks may be misaligned, resulting in higher tail
rotor pedal forces and  higher pilot workload after  failure of the No.  1
hydraulic system. Both the parts interference and the higher pedal  forces
constitute unsafe conditions.

You may obtain further information by examining the manufacturer's service
bulletin and the MCAI in the AD docket.

RELEVANT SERVICE INFORMATION

Bell  Helicopter Textron  has  issued  Alert  Service  Bulletin 230-07-36,
dated January 9, 2007. The actions  described in the MCAI are intended  to
correct  the  same unsafe  condition  as that  identified  in the  service
information.

FAA'S DETERMINATION AND PROPOSED REQUIREMENTS

This product has been approved by the aviation authority of Canada, and is
approved for  operation in  the United  States. Pursuant  to our bilateral
agreement with this  State of Design  Authority, we have  been notified of
the unsafe condition described in the MCAI and service information. We are
proposing  this  AD because  we  evaluated all  pertinent  information and
determined an unsafe condition exists and is likely to exist or develop on
other helicopters of the same type design.

DIFFERENCES BETWEEN THIS AD AND THE MCAI

We have reviewed the MCAI and related service information and, in general,
agree  with their  substance.  The  compliance times  in this  proposed AD
differ from the MCAI in that compliance would be required within the  next
150  hours time-in-service  or at  the next  annual inspection,  whichever
occurs first, instead of "at the next 150 hour or annual inspection but no
later than 31 December 2007." In making these changes, we do not intend to
differ  substantively  from the  information  provided in  the  MCAI. This
difference is highlighted in the  "Differences Between the FAA AD  and the
MCAI" section in the proposed AD.

COSTS OF COMPLIANCE

We estimate  that this  proposed AD  would affect  20 helicopters  of U.S.
registry.  We also  estimate that  it would  take about  2 work-hours  per
helicopter to adjust the rigging of the tail rotor pitch change mechanism.
The average labor rate is $80 per work-hour. A replacement yoke would cost
about $21,218,  assuming the  part is  no longer  under warranty. However,
because the service information lists this part as covered under warranty,
we have assumed  that there will  be no charge  for this part,  if needed.
Therefore, as we  do not control  warranty coverage for  affected parties,
some parties may  incur costs higher  than estimated here.  Based on these
assumptions and figures, we estimate the  cost of the proposed AD on  U.S.
operators to be $3,200, or $160 per helicopter.

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 above, 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); 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 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, 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: