Airworthiness Directives; MD Helicopters, Inc. Model 369A, H, HE, HM, HS, D, E, FF, and 500N Helicopters

[Federal Register Volume 66, Number 14 (Monday, January 22, 2001)]
[Rules and Regulations]
[Pages 6451-6452]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-1586]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-SW-63-AD; Amendment 39-12083; AD 2000-25-52]
RIN 2120-AA64


Airworthiness Directives; MD Helicopters, Inc. Model 369A, H, HE, 
HM, HS, D, E, FF, and 500N Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This document publishes in the Federal Register an amendment 
adopting Emergency Airworthiness Directive (AD) 2000-25-52 which was 
sent previously to all known U.S. owners and operators of MD 
Helicopters, Inc. (MDHI) Model 369A, H, HE, HM, HS, D, E, FF, and 500N 
helicopters. This amendment supersedes an existing emergency AD that 
requires, before further flight, performing a tap inspection on both 
the upper and lower surfaces of each main rotor blade (blade). If any 
voids are detected that exceed specified inspection requirements, the 
emergency AD also requires replacing the unairworthy blade with an 
airworthy blade before further flight. This amendment requires the same 
actions as the emergency AD and corrects the applicability to include 
the appropriate serial numbers. This amendment is prompted by the 
discovery of an error in the emergency AD. The actions specified by 
this AD are intended to prevent failure of a blade and subsequent loss 
of control of the helicopter.

DATES: Effective February 6, 2001.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of February 6, 2001.
    Comments for inclusion in the Rules Docket must be received on or 
before March 23, 2001.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 2000-SW-63-AD, 2601 Meacham Blvd., Room 
663, Fort Worth, Texas 76137. You may also send comments electronically 
to the Rules Docket at the following address: [email protected].
    The service information referenced in this AD may be obtained from 
Helicopter Technology Company, LLC, 12923 South Spring St., Los 
Angeles, CA 90061, telephone (310) 523-2750, fax (310) 523-2745. This 
information may be examined at the FAA, Office of the Regional Counsel, 
Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas; or 
at the Office of the Federal Register, 800 North Capitol Street, NW., 
suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Marc Belhumeur, Aviation Safety 
Engineer, FAA, Rotorcraft Directorate, Rotorcraft Certification Office, 
Fort Worth, Texas 76193-0170, telephone (817) 222-5177, fax (817) 222-
5783.

SUPPLEMENTARY INFORMATION: On November 21, 2000, the FAA issued 
Emergency AD 2000-24-51 that applies to MDHI Model 369A, H, HE, HM, HS, 
D, E, FF, and 500N helicopters and requires, before further flight, 
performing a tap inspection on both the upper and lower surfaces of 
each blade. If any voids are detected that exceed specified inspection 
requirements, this AD requires replacing the unairworthy blade with an 
airworthy blade before further flight. That action was prompted by a 
blade failure due to fatigue cracking that originated at corrosion pits 
on the spar bonded surfaces, resulting in an accident that destroyed a 
Hughes Model 369D helicopter. That condition, if not corrected, could 
result in failure of a blade and subsequent loss of control of the 
helicopter.
    Since the issuance of that AD, the FAA discovered an error in the 
applicability section. The part numbers are not listed correctly with 
the appropriate serial numbers and, as a result, the FAA received 
requests from operators to clarify which blade part numbers are 
affected since the emergency AD deviates from the applicable service 
bulletin. The intent of Emergency AD 2000-24-51 was not to deviate from 
the part numbers and serial numbers listed in the service bulletin. To 
assure affected blades are correctly identified, the FAA issued 
superseding Emergency AD 2000-25-52 to correct the applicability. The 
requirements for accomplishing the intent of the emergency AD remain 
the same.
    The FAA has reviewed Helicopter Technology Company, LLC, Mandatory 
Service Bulletin No. 2100-2R2, dated November 14, 2000 (SB), which 
describes procedures for performing a one-time inspection of each blade 
for skin-to-spar bonding voids before further flight.
    Since the unsafe condition described is likely to exist or develop 
on other MDHI Model 369A, H, HE, HM, HS, D, E, FF, and 500N helicopters 
of the same type designs, the FAA issued Emergency AD 2000-25-52 to 
detect a void in the bonding that could result in a crack due to 
corrosion pits on the blade spar bonded surfaces, failure of a blade, 
and subsequent loss of control of the helicopter. The AD requires, 
before further flight, performing a tap inspection on both the upper 
and lower surfaces of each blade. If any voids are detected that exceed 
specified inspection requirements, this AD requires replacing the 
unairworthy blade with an airworthy blade before further flight. The 
actions must be accomplished in accordance with the SB described 
previously. The short compliance time involved is required because the 
previously described critical unsafe condition can adversely affect the 
structural integrity and controllability of the helicopter. Therefore, 
the actions listed previously are required before further flight, and 
this AD must be issued immediately.
    Since it was found that immediate corrective action was required, 
notice and opportunity for prior public comment thereon were 
impracticable and contrary to the public interest, and good cause 
existed to make the AD effective immediately by individual letters 
issued on December 5, 2000, to all known U.S. owners and operators of 
MDHI Model 369A, H, HE, HM, HS, D, E, FF, and 500N helicopters. These 
conditions still exist, and the AD is hereby published in the Federal 
Register as an amendment to section 39.13 of the Federal Aviation 
Regulations (14 CFR 39.13) to make it effective to all persons.
    The FAA estimates that 300 helicopters of U.S. registry will be 
affected by this AD, that it will take approximately 3 work hours per 
helicopter to accomplish each inspection and 5 work hours per 
helicopter to replace 1 blade, and that the average labor rate is $60 
per work hour. Required parts will cost approximately $10,000 per 
blade. Based on these figures, the total cost impact of the AD on U.S. 
operators is estimated to be $3,630,000, assuming $12,100 per

[[Page 6452]]

helicopter for 10 inspections ($1,800) and one blade replacement 
($10,300).

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this rule by 
submitting such written data, views, or arguments as they may desire. 
Communications should identify the Rules Docket number and be submitted 
in triplicate to the address specified under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the rule. All comments submitted will be 
available in the Rules Docket for examination by interested persons. A 
report that summarizes each FAA-public contact concerned with the 
substance of this AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their mailed 
comments submitted in response to this rule must submit a self-
addressed, stamped postcard on which the following statement is made: 
``Comments to Docket No. 2000-SW-63-AD.'' The postcard will be date 
stamped and returned to the commenter.
    The regulations adopted herein will 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. Therefore, it 
is determined that this final rule does not have federalism 
implications under Executive Order 13132.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and that it is not a ``significant regulatory 
action'' under Executive Order 12866. It has been determined further 
that this action involves an emergency regulation under DOT Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
determined that this emergency regulation otherwise would be 
significant under DOT Regulatory Policies and Procedures, a final 
regulatory evaluation will be prepared and placed in the Rules Docket. 
A copy of it, if filed, 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, Incorporation by 
reference, 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. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding a new airworthiness directive 
to read as follows:

2000-25-52  MD Helicopters, Inc.: Amendment 39-12083. Docket No. 
2000-SW-63-AD. Supersedes Emergency AD 2000-24-51, Docket No. 2000-
SW-62-AD.

    Applicability: Model 369A, H, HE, HM, HS, D, E, FF, and 500N 
helicopters, with main rotor blade (blade), part number (P/N) 
500P2100-BSC (serial number (S/N) with a prefix of ``K'' and 101 
through 562); P/N 500P2100-101 or P/N 500P2100-301 (S/N with a 
prefix of ``A'' and 001 through 999 or S/N with a prefix of ``B'' 
and 001 through 529); or blade, P/N 500P2300-501 (S/N with a prefix 
of ``T'' and 101 through 107), manufactured by Helicopter Technology 
Company, LLC, 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 
otherwise 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 request approval for an 
alternative method of compliance in accordance with paragraph (b) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required before further flight, unless accomplished 
previously.
    To detect a void in the bonding that could result in a crack due 
to corrosion pits on the blade spar bonded surfaces, failure of a 
blade, and subsequent loss of control of the helicopter, accomplish 
the following:
    (a) Perform a tap inspection on both the upper and lower 
surfaces of each blade in accordance with the ``INSPECTION'' 
paragraph of Helicopter Technology Company, LLC, Mandatory Service 
Bulletin Notice No. 2100-2R2, dated November 14, 2000 (SB). If any 
voids on a blade are detected that exceed specified inspection 
requirements of the SB, replace the unairworthy blade with an 
airworthy blade before further flight.
    (b) 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. 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 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Rotorcraft Certification Office.

    (c) Special flight permits may be issued in accordance with 14 
CFR 21.197 and 21.199 to operate the helicopter to a location where 
the requirements of this AD can be accomplished.
    (d) The tap inspections shall be accomplished in accordance with 
the ``INSPECTION'' paragraph of Helicopter Technology Company, LLC, 
Mandatory Service Bulletin Notice No. 2100-2R2, dated November 14, 
2000. This incorporation by reference was approved by the Director 
of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR 
part 51. Copies may be obtained from Helicopter Technology Company, 
LLC, 12923 South Spring St., Los Angeles, CA 90061, telephone (310) 
523-2750, fax (310) 523-2745. Copies may be inspected at the FAA, 
Office of the Regional Counsel, Southwest Region, 2601 Meacham 
Blvd., Room 663, Fort Worth, Texas; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
    (e) This amendment becomes effective on February 6, 2001, to all 
persons except those persons to whom it was made immediately 
effective by Emergency AD 2000-25-52, issued December 5, 2000, which 
contained the requirements of this amendment.

    Issued in Fort Worth, Texas, on January 10, 2001.
Henry A. Armstrong,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 01-1586 Filed 1-19-01; 8:45 am]
BILLING CODE 4910-13-U

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