AD 2004-22-11

final rule

Airworthiness Directives; Eurocopter Deutschland GmbH Model EC135 P1, P2, T1, and T2 Helicopters

AD Number
2004-22-11
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 2003-SW-39-AD
FR Citation
69 FR 63442
Technical illustration of a helicopter rotor hub assembly
Problem area Rotor system

Applicability

TypeManufacturerModelDetails
aircraft Airbus Helicopters Deutschland GmbH EC135P1 Airworthiness Directives; Eurocopter Deutschland GmbH Model EC135 P1, P2, T1, and T2 Helicopters
aircraft Airbus Helicopters Deutschland GmbH EC135P2 Airworthiness Directives; Eurocopter Deutschland GmbH Model EC135 P1, P2, T1, and T2 Helicopters
aircraft Airbus Helicopters Deutschland GmbH EC135T1 Airworthiness Directives; Eurocopter Deutschland GmbH Model EC135 P1, P2, T1, and T2 Helicopters
aircraft Airbus Helicopters Deutschland GmbH EC135T2 Airworthiness Directives; Eurocopter Deutschland GmbH Model EC135 P1, P2, T1, and T2 Helicopters

Unsafe Condition

Failure of the main rotor drive aluminum torque strut assembly (strut), part number L633M1001 103 or L633M1001 105, which could lead to loss of control of the helicopter.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Insert a statement in the Rotorcraft Flight Manual to inform pilots to reduce power and land upon experiencing a thump-like sound followed by unusual vibration. Visually inspect each aluminum strut daily for cracks or breaks and replace any unairworthy strut with a titanium strut (P/N L633M1001 104). Replace all aluminum struts with titanium struts within 100 hours time-in-service if they have 400 or more hours TIS. Reduce the retirement life of aluminum struts to 500 total hours TIS or retire them by December 31, 2004, whichever comes first. Replace aluminum struts in pairs and recalculate weight and balance after installing titanium struts.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Before further flight for some actions, within 100 hours time-in-service for strut replacement, and by December 31, 2004, for life limit compliance.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Eurocopter Deutschland GmbH Model EC135 P1, P2, T1, and T2 helicopters with main rotor drive aluminum torque strut assembly (strut), part number L633M1001 103 or L633M1001 105, installed.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

This amendment supersedes an existing airworthiness directive (AD) for Eurocopter Deutschland GmbH (Eurocopter) Model EC135 P1, P2, T1, and T2 helicopters. That AD currently requires adding the AD or a statement to the Rotorcraft Flight Manual (RFM) informing the pilot to reduce power and land as soon as practicable if a thump-like sound followed by an unusual vibration occurs during flight. That AD also requires visually inspecting the main rotor drive torque strut assembly (strut) for a crack or a break, recording the inspections in the historical or equivalent record, re-marking and relocating the strut, as appropriate, and replacing any unairworthy strut with an airworthy strut. Also, that AD establishes life limits for certain struts and revises the life limit for other struts. This amendment requires the same actions as the existing AD except that it changes the visual inspection from a one-time inspection to daily inspections; reduces the life limit for aluminum struts; and eliminates the once-only transfer and remarking of certain struts. This amendment is prompted by an incident in which a pilot felt an in-flight increase in vibration and subsequent discovery of a failed strut. The actions specified by this AD are intended to prevent failure of a strut and subsequent loss of control of the helicopter.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 69, Number 211 (Tuesday, November 2, 2004)]
[Rules and Regulations]
[Pages 63442-63443]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 04-24226]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-SW-39-AD; Amendment 39-13839; AD 2004-22-11]
RIN 2120-AA64


Airworthiness Directives; Eurocopter Deutschland GmbH Model EC135 
P1, P2, T1, and T2 Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD) for Eurocopter Deutschland GmbH (Eurocopter) Model EC135 P1, P2, 
T1, and T2 helicopters. That AD currently requires adding the AD or a 
statement to the Rotorcraft Flight Manual (RFM) informing the pilot to 
reduce power and land as soon as practicable if a thump-like sound 
followed by an unusual vibration occurs during flight. That AD also 
requires visually inspecting the main rotor drive torque strut assembly 
(strut) for a crack or a break, recording the inspections in the 
historical or equivalent record, re-marking and relocating the strut, 
as appropriate, and replacing any unairworthy strut with an airworthy 
strut. Also, that AD establishes life limits for certain struts and 
revises the life limit for other struts. This amendment requires the 
same actions as the existing AD except that it changes the visual 
inspection from a one-time inspection to daily inspections; reduces the 
life limit for aluminum struts; and eliminates the once-only transfer 
and remarking of certain struts. This amendment is prompted by an 
incident in which a pilot felt an in-flight increase in vibration and 
subsequent discovery of a failed strut. The actions specified by this 
AD are intended to prevent failure of a strut and subsequent loss of 
control of the helicopter.

DATES: Effective December 7, 2004.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of December 7, 2004.

ADDRESSES: The service information referenced in this AD 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 National Archives and Records Administration 
(NARA). For information on the availability of this material at NARA, 
call 202-741-6030, or go to: <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.

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

SUPPLEMENTARY INFORMATION: A proposal to amend 14 CFR part 39 by 
superseding AD 2003-20-11, Amendment 39-13329 (68 FR 58581, October 10, 
2003), for the specified Eurocopter model helicopters was published in 
the Federal Register on June 2, 2004 (69 FR 31051). The action proposed 
to require adding the AD or a statement to the RFM informing the pilot 
to reduce power and land as soon as practicable if a thump-like sound 
followed by unusual vibration occurs during flight; visually inspecting 
the strut for a crack or a break before the first flight of each day; 
replacing any unairworthy strut with an airworthy strut; replacing all 
aluminum struts with titanium struts on or before accumulating 500 
hours time-in service (TIS) or no later than December 31, 2004, 
whichever occurs first; installing the struts in pairs; and canceling 
the once-only transfer and remarking of certain struts.
    The Luftfahrt-Bundesamt (LBA), the airworthiness authority for the 
Federal Republic of Germany, notified the FAA that an unsafe condition 
may exist on Eurocopter Model EC135 P1, P2, T1, and T2 helicopters. The 
LBA advises that the holders of affected aircraft registered in the 
Federal Republic of Germany must carry out the inspection for a crack, 
marking, replacement, and reduction of life limit of struts in 
accordance with the manufacturer's alert service bulletin.
    Eurocopter has issued Alert Service Bulletin EC135-63A-002, 
Revision 4, dated July 7, 2003 (ASB), concerning reduction in life 
limit for the strut, and visual inspections of the strut and emergency 
stop. The ASB contains errors--in paragraph 1.A., the abbreviation ``S/
N'' should be ``P/N'' and in paragraphs 1.C., 1.E.(1), and 1.E.(2), it 
incorrectly states that the ASB is Revision 3 rather than Revision 4. 
The LBA classified this ASB as mandatory and issued AD No. 2001-107/3, 
dated August 21, 2003, to ensure the continued airworthiness of these 
helicopters in the Federal Republic of Germany.
    These helicopter models are manufactured in Germany and are type 
certificated for operation in the United States under the provisions of 
14 CFR 21.29 and the applicable bilateral agreement. Pursuant to the 
applicable bilateral 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 
operation in the United States.
    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 only a minor editorial change. 
This change will neither increase the economic burden on any operator 
nor increase the scope of the AD.
    The FAA estimates that this AD will affect 50 helicopters of U.S. 
registry. It will take approximately 92.25 work hours per helicopter to 
accomplish the inspections and parts replacement at an average labor 
rate of $65 per work hour. Required parts will cost approximately 
$7,296 per helicopter. Based on these figures, we estimate the total 
cost impact of this AD on U.S. operators to be $664,612 to replace the 
aluminum struts on the entire fleet.
    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.
    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

[[Page 63443]]

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, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
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

0
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]

0
2. Section 39.13 is amended by removing Amendment 39-13329 (68 FR 
58581, October 10, 2003), and by adding a new airworthiness directive 
(AD), Amendment 39-13839, to read as follows:

2004-22-11 Eurocopter Deutschland GmbH: Amendment 39-13839. Docket 
No. 2003-SW-39-AD. Supersedes AD 2003-20-11, Amendment 39-13329, 
Docket No. 2003-SW-08-AD.

    Applicability: Model EC135 P1, P2, T1, and T2 helicopters, with 
main rotor drive aluminum torque strut assembly (strut), part number 
(P/N) L633M1001 103 or L633M1001 105, installed, certificated in any 
category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent failure of the strut and subsequent loss of control 
of the helicopter, do the following:
    (a) Before further flight, insert a copy of this AD or insert a 
statement into the Emergency Procedures Section of the Rotorcraft 
Flight Manual (RFM) to inform the pilot to reduce power and land as 
soon as practicable if a thump-like sound followed by an unusual 
vibration occurs during flight.
    (b) Before the first flight of each day, using a light and 
mirror, inspect each aluminum strut for a crack or a break by 
following the Accomplishment Instructions, paragraph 3.B. of 
Eurocopter Alert Service Bulletin EC135-63A-002, Revision 4, dated 
July 7, 2003 (ASB). Replace any cracked or broken strut with a new 
titanium strut, P/N L633M1001 104, before further flight.
    (c) Within the next 100 hours time-in-service (TIS), for each 
aluminum strut with 400 or more hours TIS, replace each aluminum 
strut with a titanium strut, P/N L633M1001 104.
    (d) This AD revises the Airworthiness Limitations section of the 
maintenance manual by reducing the retirement life of each aluminum 
strut, P/N L633M1001 103 and L633M1001 105, to 500 total hours TIS 
or retiring them no later than December 31, 2004, whichever comes 
first.
    (e) The aluminum struts must be replaced with titanium struts in 
pairs and at the same time. Installing one aluminum strut and one 
titanium strut is not authorized. After installing titanium struts, 
recalculate the weight and balance using 0.356kg as the weight and 
1498.76kgmm as the moment for both titanium struts.

    Note 1: The once-only transferring and remarking of certain 
aluminum struts provided in the superseded AD are no longer 
authorized.

    (f) Replacing aluminum struts, P/N L633M1001 103 and L633M1001 
105, with titanium struts, P/N L633M1001 104, constitutes 
terminating action for the requirements of this AD. Titanium struts 
have no life limit.
    (g) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Contact the Safety Management Group for information about previously 
approved alternative methods of compliance.
    (h) The inspections shall be done in accordance with Eurocopter 
Alert Service Bulletin EC135-63A-002, Revision 4, dated July 7, 
2003. The Director of the Federal Register approved the 
incorporation by reference 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 
National Archives and Records Administration (NARA). For information 
on the availability of this material at NARA, call 202-741-6030, or 
go to: <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
    (i) This amendment becomes effective on December 7, 2004.

    Note 2: The subject of this AD is addressed in Luftfahrt-
Bundesamt (Federal Republic of Germany) AD 2001-107/3, dated August 
21, 2003.


    Issued in Fort Worth, Texas, on October 22, 2004.
David A. Downey,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 04-24226 Filed 11-1-04; 8:45 am]
BILLING CODE 4910-13-P

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