[Federal Register Volume 65, Number 24 (Friday, February 4, 2000)]
[Proposed Rules]
[Pages 5453-5455]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-2402]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-SW-73-AD]


Airworthiness Directives; Eurocopter Deutschland GMBH Model MBB-
BK 117 A-1, A-3, A-4, B-1, B-2, and C-1 Helicopters

AGENCY:  Federal Aviation Administration, DOT.

ACTION:  Notice of proposed rulemaking (NPRM).

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SUMMARY:  This document proposes the adoption of a new airworthiness 
directive (AD) applicable to Eurocopter Deutschland GMBH (ECD) Model 
MBB-BK 117 A-1, A-3, A-4, B-1, B-2, and C-1 helicopters. This proposal 
would require modifying the engine and transmission cowling doors 
(cowling doors). This proposal is prompted by an emergency landing of 
an ECD Model MBB-BK 117 helicopter after the No. 1 engine cowling 
opened, separated from the helicopter, and struck the main and tail 
rotor blades resulting in a tail rotor imbalance and subsequent 
departure of the tail rotor gear box from the helicopter. The actions 
specified by the proposed AD are intended to prevent the cowling doors 
opening during flight, separating from the helicopter and impacting the 
main or tail rotor blades, and subsequent loss of control of the 
helicopter.

DATES:  Comments must be received on or before April 4, 2000.

ADDRESSES:  Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 99-SW-73-AD, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas. Comments may be inspected at this location between 9 
a.m. and 3 p.m., Monday through Friday, except Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from American Eurocopter Corporation, 2701 Forum Drive, Grand 
Prairie, Texas 75053-4005, telephone (972) 641-3460, fax (972) 641-
3527. This information may be examined at the FAA, Office of the 
Regional Counsel, Southwest Region, Room 663, Fort Worth, Texas.

FOR FURTHER INFORMATION CONTACT:  Richard A. Monschke, Aerospace 
Engineer, FAA, Rotorcraft Directorate, Rotorcraft Standards Staff, Fort 
Worth, Texas 76193-0110, telephone (817) 222-5116, fax (817) 222-5961.

SUPPLEMENTARY INFORMATION:

[[Page 5454]]

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed 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 above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket No. 99-SW-73-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 99-SW-73-AD, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas 76137.

Discussion

    Luftfahrt-Bundesamt (LBA), the airworthiness authority for the 
Federal Republic of Germany, notified the FAA that an unsafe condition 
may exist on ECD Model MBB-BK 117 A-1, A-3, A-4, B-1, B-2, and C-1 
helicopters. The LBA advises that the cowling doors should be modified 
to install a hook on each cowling door and install the respective hook 
retainers on the engine floor and on the transmission floor.
    ECD has issued Service Bulletin No. MBB-BK 117-20-109, Revision 2, 
dated April 30, 1999 (SB), which specifies modifying the cowling doors 
by installing a hook on each cowling door and installing the respective 
hook retainers on the engine and transmission floor to prevent cowling 
doors opening fully during flight. The LBA has classified the ECD SB as 
mandatory and issued AD No. 1999-302, dated September 23, 1999, to 
ensure the continued airworthiness of these helicopters in the Federal 
Republic of Germany.
    These helicopter models are manufactured in the Federal Republic of 
Germany and are type certificated for operation in the United States 
under the provisions of section 21.29 of the Federal Aviation 
Regulations (14 CFR 21.29) and the applicable bilateral airworthiness 
agreement. Pursuant to this bilateral airworthiness agreement, the 
Federal Republic of Germany has kept the FAA informed of the situation 
described above. The FAA has examined the findings of the Federal 
Republic of Germany, reviewed all available information, and determined 
that AD action is necessary for products of this type design that are 
certificated for operation in the United States.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other ECD Model MBB-BK 117 A-1, A-3, A-4, B-1, B-2, 
and C-1 of the same type designs registered in the United States, the 
proposed AD would require modifying the cowling doors to prevent the 
cowling doors from opening during flight. The actions would be required 
to be accomplished in accordance with the SB described previously.
    The FAA estimates that 140 helicopters of U.S. registry would be 
affected by this proposed AD, that it would take approximately 28 work 
hours per helicopter to accomplish the proposed actions, and that the 
average labor rate is $60 per work hour. Required parts would cost 
approximately $1620 per helicopter. Based on these figures, the total 
cost impact of the proposed AD on U.S. operators is estimated to be 
$462,000.
    The regulations proposed herein 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. Therefore, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    For the reasons discussed above, I certify that 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) if promulgated, 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 copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting 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.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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:

Eurocopter Deutschland GMBH: Docket No. 99-SW-73-AD.

    Applicability: Model MBB-BK 117 A-1, A-3, A-4, B-1, B-2, and C-1 
helicopters, serial numbers 7001 through 7253 and 7500 through 7523, 
with transmission door cowling, left hand, part number (P/N) 117-
23206-51 or 117-233731, right hand, P/N 117-23206-52 or 117-233741, 
and engine door cowling left hand, P/N 117-23303-51 or 117-23303-53, 
right hand, P/N 117-23303-52 or 117-23303-54, 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 within 6 calendar months, unless accomplished 
previously.

    To prevent the engine and transmission cowling doors (cowling 
doors) opening during flight, separating from the helicopter and 
impacting the main or tail rotor blades, and subsequent loss of 
control of the helicopter, accomplish the following:
    (a) Modify the cowling doors in accordance with paragraph 2.B., 
Work Procedure, and

[[Page 5455]]

2.C., Conclusions, of Eurocopter Deutschland GMBH Service Bulletin 
SB-MBB-BK 117-20-109, Revision 2, dated April 30, 1999 (SB).


    Note 2:  Adjustment and functional testing of the hook system in 
accordance with paragraph 2.B.8 of the SB is critical after 
installation.


    (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, Regulations Group, Rotorcraft 
Directorate, FAA. Operators shall submit their requests through an 
FAA Principal Maintenance Inspector, who may concur or comment and 
then send it to the Manager, Regulations Group.


    Note 3:  Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Regulations Group.


    (c) Special flight permits may be issued in accordance with 
Secs. 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.


    Note 4:  The subject of this AD is addressed in Luftfahrt-
Bundesamt (the Federal Republic of Germany) AD No. 1999-302, dated 
September 23, 1999.


    Issued in Fort Worth, Texas, on January 26, 2000.
Henry A. Armstrong,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 00-2402 Filed 2-3-00; 8:45 am]
BILLING CODE 4910-13-U