[Federal Register Volume 62, Number 48 (Wednesday, March 12, 1997)]
[Rules and Regulations]
[Pages 11320-11321]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-6089]
[[Page 11320]]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 94-SW-25-AD; Amendment 39-9960; AD 97-06-03]
RIN 2120-AA64
Airworthiness Directives; Bell Helicopter Textron, Inc. (BHTI)
Model 214ST Helicopters
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment supersedes an existing airworthiness directive
(AD), applicable to Bell Helicopter Textron, Inc. (BHTI) Model 214ST
helicopters, that currently establishes a mandatory retirement life of
50,000 high-power events for the main rotor mast (mast). This amendment
requires changing the retirement life for the mast from high-power
events to a maximum accumulated Retirement Index Number (RIN) of
140,000 and applying this RIN to an additional part-numbered mast. This
amendment is prompted by fatigue analyses and tests that show certain
masts fail sooner than originally anticipated because of an
unanticipated high number of takeoffs and external load lifts in
addition to the deterioration in strength that occurs under other
operating conditions. The actions specified by this AD are intended to
prevent fatigue failure of the mast, which could result in failure of
the main rotor system and subsequent loss of control of the helicopter.
EFFECTIVE DATE: April 16, 1997.
FOR FURTHER INFORMATION CONTACT: Mr. Uday Garadi, Aerospace Engineer,
FAA, Rotorcraft Certification Office, Rotorcraft Directorate, Fort
Worth, Texas 76193-0170, telephone (817) 222-5157, fax (817) 222-5959.
SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal
Aviation Regulations (14 CFR part 39) by superseding AD 94-15-04,
Amendment 39-8975 (59 FR 37155, July 21, 1994), which is applicable to
BHTI Model 214ST helicopters, was published in the Federal Register on
November 14, 1996 (61 FR 58356). That action proposed to require
creation of a component history card or equivalent record on which to
record RIN counts, and to establish a retirement life of a maximum
accumulated RIN for the mast of 140,000.
Interested persons have been afforded an opportunity to participate
in the making of this amendment. No comments were received on the
proposal or the FAA's determination of the cost to the public. The FAA
has determined that air safety and the public interest require the
adoption of the rule as proposed.
The FAA estimates that nine helicopters of U.S. registry will be
affected by this AD, that it will take approximately (1) 48 work hours
per helicopter to replace the mast; (2) 2 work hours per helicopter to
create the component history card or equivalent record (record); and
(3) 10 work hours per helicopter to maintain the record each year, and
that the average labor rate is $60 per work hour. Required parts will
cost approximately $17,267 per mast. Based on these figures, the total
cost impact of the proposed AD on U.S. operators is estimated to be
$36,700 for the first year and $35,800 for each subsequent year. These
costs assume replacement of the mast in one-sixth of the fleet each
year, creation and maintenance of the records for all the fleet the
first year, and creation of one-sixth of the fleet's records and
maintenance of the records for all the fleet each subsequent year.
The regulations adopted herein will not have substantial direct
effects 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, in
accordance with Executive Order 12612, it is determined that this final
rule does not have sufficient federalism implications to warrant the
preparation of a Federalism Assessment.
For the reasons discussed above, I certify that this 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) 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 final evaluation has been prepared for this action
and it is contained in the Rules Docket. A copy of it may be obtained
from 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.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends 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 USC 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by removing Amendment 39-8975 (59 FR
37155), and by adding a new airworthiness directive (AD), Amendment 39-
9960, to read as follows:
AD 97-06-03 Bell Helicopter Textron, Inc. (BHTI): Amendment 39-
9960. Docket No. 94-SW-25-AD. Supersedes AD 94-15-04, Amendment 39-
8975.
Applicability: Model 214ST helicopter with main rotor mast
(mast), part number (P/N) 214-040-090-109 or P/N 214-040-090-121,
installed, certificated in any category.
Note 1: This AD applies to each helicopter identified in the
preceding applicability provision, regardless of whether it has been
modified, altered, or repaired in the area subject to the
requirements of this AD. For helicopters that have been modified,
altered, or repaired so that the performance of the requirements of
this AD is affected, the owner/operator must use the authority
provided in paragraph (e) to request approval from the FAA. This
approval may address either no action, if the current configuration
eliminates the unsafe condition, or different actions necessary to
address the unsafe condition described in this AD. Such a request
should include an assessment of the effect of the changed
configuration on the unsafe condition addressed by this AD. In no
case does the presence of any modification, alteration, or repair
remove any helicopter from the applicability of this AD.
Compliance: Required within 25 hours time-in-service (TIS) after
the effective date of this AD, unless accomplished previously.
To prevent fatigue failure of the mast, which could result in
failure of the main rotor system and subsequent loss of control of
the helicopter, accomplish the following:
(a) Create a component history card or an equivalent record for
the affected mast.
(b) Determine and record the accumulated Retirement Index Number
(RIN) to date on the mast as follows:
(1) For operators with mast, P/N 214-040-090-109, multiply the
takeoffs and external load lifts (high-power events) total to date
by 2.8 (round up the result to the next whole number).
(2) For operators with mast, P/N 214-040-090-121, multiply the
factored flight hour total to date by 14 (round up the result to the
next whole number).
(3) Record on the component history card the accumulated RIN.
Note 2: BHTI Alert Service Bulletin (ASB) No. 214ST-94-67, dated
November 7, 1994, pertains to this subject.
(c) After complying with paragraphs (a) and (b) of this AD,
during each operation thereafter, maintain a count of the number and
type of external load lifts and the
[[Page 11321]]
number of takeoffs performed, and at the end of each day's
operations, increase the accumulated RIN on the component history
card as follows:
(1) Increase the RIN by 2 for each takeoff.
(2) Increase the RIN by 2 for each external load lift operation;
or, increase the RIN by 4 for each external load lift operation in
which the load is picked up at a higher elevation and released at a
lower elevation, and the difference in elevation between the pickup
point and the release point is 200 feet or greater.
(d) Remove the mast, P/N 214-040-090-109 or -121, from service
on or before attaining an accumulated RIN of 140,000. The mast is no
longer retired based upon flight hours. This AD revises the
Airworthiness Limitations Section of the maintenance manual by
establishing a new retirement life for the mast of 140,000 RIN.
(e) An alternative method of compliance or adjustment of the
compliance time that provides an acceptable level of safety may be
used if approved by the Manager, Rotorcraft Certification Office,
FAA, Rotorcraft Directorate. Operators shall submit their requests
through an FAA Principal Maintenance Inspector, who may concur or
comment and then send it to the Manager, Rotorcraft Certification
Office.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Rotorcraft Certification Office.
(f) Special flight permits may be issued in accordance with
sections 21.197 and 21.199 of the Federal Aviation Regulations (14
CFR 21.197 and 21.199) to operate the helicopter to a location where
the requirements of this AD can be accomplished.
(g) This amendment becomes effective on April 16, 1997.
Issued in Fort Worth, Texas, on February 26, 1997.
Larry M. Kelly,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 97-6089 Filed 3-11-97; 8:45 am]
BILLING CODE 4910-13-U
