[Federal Register Volume 64, Number 231 (Thursday, December 2, 1999)]
[Rules and Regulations]
[Pages 67471-67473]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-30623]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-SW-59-AD; Amendment 39-11439; AD 99-22-01]
RIN 2120-AA64


Airworthiness Directives; Eurocopter Deutschland GmbH Model EC135 
P1 and T1 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 Airworthiness Directive (AD) 99-22-01, which was sent 
previously to all known U.S. owners and operators of Eurocopter 
Deutschland GmbH (ECD) Model EC135 P1 and T1 helicopters by individual 
letters. This AD requires, before further flight and at specified time 
intervals until a modified tail boom connecting frame flange (frame 
flange) is installed, inspecting and replacing, if necessary, the frame 
flange. This AD also requires, within 7 days, installing an additional 
bearing support on the frame flange. Thereafter, this AD requires 
visually inspecting the frame flange for cracks or misalignment of the 
slippage marks at specified time intervals. This amendment is prompted 
by the discovery of a crack in the frame flange at the attachment 
points of the tail rotor drive shaft bearing support. The actions 
specified by this AD are intended to prevent a fracture of the bearing 
frame flange, failure of the tail rotor drive shaft, and subsequent 
loss of control of the helicopter.

DATES: Effective December 17, 1999, to all persons except those persons 
to whom it was made immediately effective by Emergency Priority Letter 
AD 99-22-01, issued on October 12, 1999, which contained the 
requirements of this amendment.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of December 17, 1999.
    Comments for inclusion in the Rules Docket must be received on or 
before January 31, 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-59-AD, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas 76137.
    The applicable service information 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, 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: Paul J. Madej, Aerospace Engineer, 
FAA, Rotorcraft Directorate, Rotorcraft Standards Staff, 2601 Meacham 
Blvd., Fort Worth, Texas 76137, telephone (817) 222-5125, fax (817) 
222-5961.

SUPPLEMENTARY INFORMATION: On October 12, 1999, the FAA issued 
Emergency Priority Letter AD 99-22-01, applicable to ECD Model EC135 P1 
and T1 helicopters, which requires, before further flight and at 
specified time intervals until an additional bearing support bracket is 
installed on the frame flange, inspecting and replacing, if necessary, 
the frame flange. The AD also requires, within 7 days, adding the 
additional bearing support bracket to the frame flange. Thereafter, the 
AD requires visually inspecting the frame flange for cracks or 
misalignment of the slippage marks at specified time intervals. That 
action was prompted by the discovery of a crack in the frame flange at 
the attachment points of the tail rotor drive shaft bearing support. 
The crack, discovered during an inspection of an ECD Model EC135

[[Page 67472]]

helicopter, was caused by metal fatigue due to unanticipated loads at 
this location. This condition, if not corrected, could result in a 
fracture of the bearing frame flange, failure of the tail rotor drive 
shaft, and subsequent loss of control of the helicopter.
    The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority 
for the Federal Republic of Germany, notified the FAA that an unsafe 
condition may exist on ECD Model EC135 P1 and T1 helicopters, serial 
numbers (S/N) 0005 through 0120. The LBA issued AD 1999-199/3, dated 
October 5, 1999, applicable to ECD Model EC135 helicopters, S/N 0005 
through 0120. The LBA advises that during an inspection a crack was 
detected on the frame flange of the tail rotor drive shaft bearing 
support.
    The FAA has reviewed ECD Alert Service Bulletins EC 135-53A-009, 
dated March 23, 1999, and EC 135-53A-010, Revision 2, dated July 22, 
1999 (ASB). The ASB's describe procedures for conducting a dye-
penetrant crack inspection before further flight and conducting 
repetitive inspections at intervals not to exceed 15 hours time-in-
service (TIS) until the helicopters are fitted with an additional 
bearing support bracket at bearing location I as identified in the 
ASB's. ASB EC 135-53A-010, Revision 2, also defines the 50-hour 
repetitive inspection necessary after the modification is accomplished.
    This helicopter model is manufactured in the Federal Republic of 
Germany and is type certificated for operation in the United States 
under the provision 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 LBA 
has kept the FAA informed of the situation described above. The FAA has 
examined the findings of the LBA, reviewed all available information, 
and determined that AD action is necessary for products of this type 
design that are certificated for operations in the United States.
    Since the unsafe condition described is likely to exist or develop 
on other ECD Model EC135 P1 and T1 helicopters of the same type design, 
the FAA issued Emergency Priority Letter AD 99-22-01 to prevent a 
fracture of the bearing frame flange, failure of the tail rotor drive 
shaft, and subsequent loss of control of the helicopter. The AD 
requires, before further flight, conducting a dye-penetrant inspection 
of the tail boom frame flange at the attachment points of the tail 
rotor drive shaft bearing as shown in location I in Figure 1 of the 
ASB's. If a crack is found, the AD requires replacing the tail boom 
frame flange before further flight. The dye-penetrant inspection of the 
frame flange is required at intervals not to exceed 15 hours TIS until 
an additional bearing support bracket has been installed. The AD also 
requires, within 7 days, modifying the frame flange by installing an 
additional bearing support bracket. After modifying the frame flange, a 
visual inspection for a crack or for misalignment of the slippage marks 
is to be conducted at intervals not to exceed 50 hours TIS. The actions 
must be accomplished in accordance with the ASB's described previously. 
The short compliance time involved is required because the previously 
described critical unsafe condition can adversely affect the structural 
integrity of the helicopter. Therefore, inspecting and replacing, if 
necessary, the frame flange is required before further flight; 
modifying the frame flange is required within 7 days; and inspecting 
the modified frame flange is required at 50 hour TIS intervals; 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 October 12, 1999 to all known U.S. owners and operators of 
ECD Model EC135 P1 and T1 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 14 helicopters of U.S. registry will be 
affected by this AD, that it will take approximately 2 work hours per 
helicopter to accomplish the dye-penetrant inspections, 48 work hours 
per helicopter to replace the frame flange, if necessary, and 3 work 
hours per helicopter to install the additional bearing support bracket 
on the frame flange. The average labor rate is $60 per work hour. The 
manufacturer has stated that required parts will be provided at no 
cost. Based on these figures, the total cost impact of the AD on U.S. 
operators is estimated to be $24,360, assuming conducting one dye-
penetrant inspection on each helicopter, replacing the frame flange in 
half the fleet, and modifying the frame flange in all the fleet.

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, both before and after the closing date for comments, 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 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. 99-SW-59-AD.'' The postcard will be date stamped and 
returned to the commenter.
    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.
    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

[[Page 67473]]

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:

AD 99-22-01  Eurocopter Deutschland GmbH: Amendment 39-11439. Docket 
No. 99-SW-59-AD.

    Applicability: Model EC135 P1 and T1 helicopters, serial numbers 
0005 through 0120, inclusive, 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 (c) 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 as indicated, unless accomplished 
previously.
    To prevent a fracture of the bearing connecting frame flange 
(frame flange), failure of the tail rotor drive shaft, and 
subsequent loss of control of the helicopter, accomplish the 
following:
    (a) Before further flight, conduct a dye-penetrant inspection of 
the tail boom frame flange at the attachment points of the tail 
rotor drive shaft bearing (see location I in Figure 1 in Eurocopter 
Deutschland GmbH (ECD) Alert Service Bulletin (ASB) EC 135-53A-010, 
Revision 2, dated July 22, 1999) in accordance with the 
Accomplishment Instructions, paragraph 3.A., of ASB EC 135-53A-010, 
Revision 2, dated July 22, 1999, and Figure 1 of ASB 135-53A-009, 
dated March 23, 1999. If a crack is found, replace the unairworthy 
frame flange with an airworthy frame flange. Thereafter, conduct the 
dye-penetrant inspection at intervals not to exceed 15 hours time-
in-service (TIS) until the requirements in paragraph (b) of this AD 
are accomplished.
    (b) Within 7 days, install an additional bearing support bracket 
on the frame flange in accordance with the Accomplishment 
Instructions, paragraph 3.B., of ASB EC 135-53A-010, Revision 2 
dated July 22, 1999. Thereafter, at intervals not to exceed 50 hours 
TIS, inspect for a crack or for misalignment of the slippage marks 
on the frame flange.
    (c) 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 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Regulations Group, Rotorcraft Directorate.

    (d) 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.
    (e) The dye-penetrant inspections shall be done in accordance 
with the Accomplishment Instructions, paragraph 3.A., of Eurocopter 
Deutschland GmbH Alert Service Bulletin EC 135-53A-010, Revision 2, 
dated July 22, 1999, and Figure 1 of Eurocopter Deutschland GmbH 
Alert Service Bulletin 135-53A-009, dated March 23, 1999. The 
modification shall be done in accordance with the Accomplishment 
Instructions, paragraph 3.B., of Eurocopter Deutschland GmbH Alert 
Service Bulletin EC 135-53A-010, Revision 2, dated July 22, 1999. 
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 American Eurocopter Corporation, 
2701 Forum Drive, Grand Prairie, Texas 75053-4005, telephone (972) 
641-3460, fax (972) 641-3527. 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.
    (f) This amendment becomes effective on December 17, 1999, to 
all persons except those persons to whom it was made immediately 
effective by Emergency Priority Letter AD 99-22-01, issued October 
12, 1999, which contained the requirements of this amendment.

    Issued in Fort Worth, Texas, on November 17, 1999.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 99-30623 Filed 12-1-99; 8:45 am]
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