[Federal Register Volume 59, Number 139 (Thursday, July 21, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-17795]


  Federal Register / Vol. 59, No. 139 / Thursday, July 21, 1994 /
  
[[Page Unknown]]

[Federal Register: July 21, 1994]


                                                   VOL. 59, NO. 139

                                            Thursday, July 21, 1994

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 93-SW-19-AD; Amendment 39-8975; AD 94-15-04]

 

Airworthiness Directives; Bell Helicopter Textron, Inc. Model 
214ST Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to Bell Helicopter Textron, Inc. Model 214ST helicopters, 
that requires creation of a component history card and establishes an 
additional retirement life for the main rotor mast (mast). This 
amendment is prompted by fatigue analysis and retesting that showed 
that the mast is sensitive to frequent takeoffs and external load lifts 
(high-power events) in addition to time-in-service. The actions 
specified by this AD are intended to prevent fatigue failure of the 
mast, loss of the main rotor system, and subsequent loss of control of 
the helicopter.

EFFECTIVE DATE: August 25, 1994.

ADDRESSES: This AD and any related information may be examined in the 
Rules Docket at the Federal Aviation Administration (FAA), Office of 
the Assistant Chief Counsel, 2601 Meacham Blvd., Room 663, Fort Worth, 
Texas.

FOR FURTHER INFORMATION CONTACT: Mr. Lance Gant, Aerospace Engineer, 
Rotorcraft Certification Office, FAA, Southwest Region, Rotorcraft 
Directorate, Fort Worth, Texas 76193-0170, telephone (817) 222-5141, 
fax (817) 222-5959.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations to include an airworthiness directive (AD) that is 
applicable to Bell Helicopter Textron, Inc. Model 214ST helicopters was 
published in the Federal Register on November 12, 1993 (58 FR 59967). 
That action proposed to require creation of a component historical 
service record and proposed to establish an additional retirement life 
of 50,000 high-power events for the main rotor mast (mast), part number 
(P/N) 214-040-090-109. Currently, the mast has a retirement life of 
10,000 hours' time-in-service.
    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 with some editorial changes. The FAA 
has determined that these changes will neither increase the economic 
burden on any operator nor increase the scope of the AD.
    In the notice, the cost estimates associated with this AD were 
based on replacement of the mast and creation of the component history 
card for the entire fleet. This rule contains cost estimates for one-
sixth of the fleet each year instead of the entire fleet, as in the 
notice. Additionally, the notice referred to the component history card 
as a ``historical service record or component history card''. This rule 
refers to it as a ``component history card or an equivalent record.'' 
Also, paragraph (d) of this rule was expanded to specify the details of 
the new retirement life. These changes will not increase the scope of 
the AD. However, the FAA has performed a more detailed cost analysis 
and has determined that, when factoring in the creation and maintenance 
of the component history card or equivalent record, the anticipated 
costs are $9,163 higher than the proposed amount for the first year, 
and $7,879 higher than the proposed amount for each subsequent year. In 
the proposal, the cost of this AD was estimated to be $53,970 each year 
($323,820 for the total fleet).
    The FAA estimates that 14 helicopters of U.S. registry will be 
affected by this AD, that (1) it will take approximately 24 work hours 
per helicopter to replace the affected part due to the new method of 
determining the retirement life required by this AD, (2) it will take 
approximately 2 work hours per helicopter to create the component 
history card or equivalent record (record), (3) it will take 
approximately 10 work hours per helicopter to maintain the record each 
year, and (4) the average labor rate is $55 per work hour. Required 
parts will cost approximately $21,810 per helicopter. Based on these 
figures, the total cost impact of the AD on U.S. operators for the 
first year is estimated to be $63,133, and each subsequent year to be 
$61,849. 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 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 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13   [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

AD 94-15-04  Bell Helicopter Textron, Inc.: Amendment 39-8975. 
Docket Number 93-SW-19-AD.

    Applicability: Model 214ST helicopters, with main rotor mast 
(mast), part number (P/N) 214-040-090-109 installed, certificated in 
any category.
    Compliance: Required as indicated, unless accomplished 
previously. To prevent fatigue failure of the mast, loss of the main 
rotor system, and subsequent loss of control of the helicopter, 
accomplish the following:
    (a) Within 10 calendar days after the effective date of this 
airworthiness directive (AD), accomplish the following:
    (1) Create a component history card or an equivalent record for 
the affected mast.
    (2) Determine and record the total time-in-service (TIS) 
accumulated for the mast as follows:
    (i) If the TIS of the mast is unknown, use a TIS of 900 hours' 
per year. Prorate the hours for a partial year.
    (ii) If the TIS is known, use that total TIS.
    (3) Determine and record the accumulated takeoffs and external 
load lifts (high-power events) for the mast as follows:
    (i) If the number of high-power events is unknown, assign 11 
high-power events for each hour TIS obtained in accordance with 
paragraph (a)(2).
    (ii) If the number of high-power events is known, record that 
number as total accumulated high-power events.
    (b) After compliance with paragraph (a) of this AD, continue to 
record the TIS and high-power events and add the high-power events 
to the previously recorded sum.
    (c) Remove the mast from further service in accordance with the 
following:
    (1) For each mast with 9,900 hours' or more total TIS on the 
effective date of this AD, remove and replace the mast within the 
next 100 hours' TIS.
    (2) For each mast with less than 9,900 hours' total TIS on the 
effective date of this AD, remove and replace the mast before it 
attains 10,000 hours' TIS.
    (3) For each mast with 48,900 or more high-power events on the 
effective date of this AD, remove and replace the mast on or before 
the accumulation of an additional 1,100 high-power events.
    (4) For each mast with less than 48,900 high-power events on the 
effective date of this AD, remove and replace the mast before it 
attains 50,000 high-power events.
    (d) This AD revises the Airworthiness Limitations Section of the 
maintenance manual by establishing a new retirement life for the 
mast of 10,000 hours' TIS, or 50,000 high-power events, whichever 
occurs first. However, for masts with 9,900 hours' or more TIS or 
48,900 or more high-power events on the effective date of this AD, 
those masts need not be retired until on or before the accumulation 
of an additional 100 hours' TIS or 1,100 high-power events, 
respectively.
    (e) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used when 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: 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 August 25, 1994.

    Issued in Fort Worth, Texas, on July 13, 1994.
James D. Erickson,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 94-17795 Filed 7-20-94; 8:45 am]
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