[Federal Register Volume 65, Number 88 (Friday, May 5, 2000)]
[Rules and Regulations]
[Pages 26122-26124]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-11058]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-SW-02-AD; Amendment 39-11708; AD 2000-08-22]
RIN 2120-AA64


Airworthiness Directives; MD Helicopters Inc. Model 369D, 369E, 
500N, and 600N Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) 
applicable to MD Helicopters Inc. (MDHI) Model 369D, 369E, 500N, and 
600N helicopters with certain analog/digital turbine outlet temperature 
(TOT) indicators installed. This action requires repetitive calibration 
testing of the TOT indicating system and corrective actions if 
necessary. This amendment is prompted by seven reports of erroneous TOT 
readings and two reports of incorrect wiring harness terminal lugs on 
the thermocouple wiring. The actions specified in this AD are intended 
to prevent an erroneous TOT indication, damage to critical engine 
components, loss of engine power, and a subsequent forced landing.

DATES: Effective May 22, 2000.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 22, 2000.
    Comments for inclusion in the Rules Docket must be received on or 
before July 5, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 2000-SW-02, 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].

[[Page 26123]]

    The service information referenced in this AD may be obtained from 
MD Helicopters Inc., Attn: Customer Support Division, 4555 E. McDowell 
Rd., Mail Stop M615-GO48, Mesa, Arizona 85215-9797, telephone 1-800-
388-3378 or 480-346-6387, datafax 480-346-6813. This information may be 
examined at the FAA, Office of the Regional Counsel, Southwest Region, 
2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137; or at the Office 
of the Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.

FOR FURTHER INFORMATION CONTACT: Elizabeth Bumann, Aviation Safety 
Engineer, FAA, Los Angeles Aircraft Certification Office, 3960 
Paramount Blvd., Lakewood, California 90712-4137, telephone (562) 627-
5265; fax (562) 627-5210.

SUPPLEMENTARY INFORMATION: This amendment adopts a new airworthiness 
directive (AD) applicable to MDHI Model 369D, 369E, 500N, and 600N 
helicopters with certain analog/digital TOT indicators installed. This 
action requires repetitive testing of the TOT indicating system to 
verify correct calibration and to take corrective actions if necessary. 
This amendment is prompted by seven reports of erroneous TOT readings, 
up to 100 degrees Celsius low. This amendment is also prompted by two 
reports of incorrect wiring harness terminal lugs on the thermocouple 
wiring. Reports indicated that some of the TOT readings did not agree 
with the engine Electronic Control Unit (ECU) and some readings were 
found to be 4 degrees Celsius to 17 degrees Celsius low. The actions 
specified in this AD are intended to prevent erroneous TOT indications, 
which could prevent the flight crew from detecting that an engine 
temperature limitation has been exceeded. This condition, if not 
corrected, could result in damage to critical engine components, loss 
of engine power, and a subsequent forced landing.
    The FAA has reviewed MDHI Service Bulletins SB369D-199, SB369E-093, 
SB500N-019 (for Model 369D, 369E, and 500N helicopters) and SB600N-026 
(for Model 600N helicopters), both dated January 11, 2000. These 
service bulletins describe procedures for calibration testing of the 
TOT indicating system and corrective actions if necessary. The 
corrective actions include inspecting TOT wire harness terminal lugs, 
connector pins, and sockets to verify correct material and 
installation; retesting the TOT indicating system; and replacing any 
unairworthy part with an airworthy part. For Model 600N helicopters, 
Part III of the service bulletin also describes procedures for 
verifying the electronic control unit (ECU) TOT calibration.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other MDHI model helicopters of these same type 
designs, this AD is being issued to prevent an erroneous TOT 
indication, damage to critical engine components, loss of engine power, 
and a subsequent forced landing. The actions are required to be 
accomplished in accordance with the service bulletins described 
previously, except as discussed in the following paragraphs. The short 
compliance time involved is required because the previously described 
critical unsafe condition can adversely affect the engine, causing a 
loss of engine power and a subsequent forced landing of the helicopter. 
Therefore, initial testing of the TOT indicating system to verify 
correct calibration is required within the next 50 hours time-in-
service (TIS) or on or before June 15, 2000, whichever occurs earlier, 
and this AD must be issued immediately.
    This AD is an interim action. The manufacturer has advised that it 
currently is developing a modification that will permanently address 
the unsafe condition.
    The service bulletins specify certain serial numbered helicopters 
with the affected analog/digital TOT indicator installed. The FAA has 
determined that any Model 369D, 369E, 500N, and 600N helicopter may 
have the analog/digital TOT indicator, part number (P/N) 369D24513-1 or 
P/N 9A3420, installed, since the helicopter manufacturer has not 
developed a modification to correct the unsafe condition. Even 
subsequently manufactured Model 369D, 369E, 500N, and 600N helicopters 
may have these analog/digital TOT indicators installed.
    The service bulletins recommend accomplishing the TOT system 
calibration test within 100 hours TIS. The FAA has determined that a 
100-hour TIS compliance time would not address the unsafe condition in 
a timely manner. In developing an appropriate compliance time for this 
AD, the FAA considered not only the manufacturer's recommendation, but 
the degree of urgency associated with addressing the unsafe condition, 
the average utilization of the affected fleet, and the time necessary 
to perform the test. In light of all these factors, the FAA finds a 
compliance time within the next 50 hours TIS or on or before June 15, 
2000, whichever occurs first, for initiating the required test is an 
appropriate interval of time that affected helicopters can operate 
without compromising safety.
    Additionally, the FAA has determined that long-term continued 
operational safety will be better assured by repetitive testing of the 
TOT indicating system at intervals not to exceed 300 hours TIS, rather 
than a one-time test, because of reports that the system calibration 
may shift with service time. A one-time test may not provide the degree 
of safety assurance necessary to ensure that the TOT indicator is 
properly calibrated over time.
    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.
    The FAA estimates that 566 helicopters will be affected by this 
proposed AD, that it will take approximately 0.5 work hour to 
accomplish the test, and that the average labor rate is $60 per work 
hour. The manufacturer has represented in the service bulletins that 
parts will be provided at no cost to the operator. Based on these 
figures, the total cost impact of the AD on U.S. operators is estimated 
to be $16,980, per test cycle for the entire 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

[[Page 26124]]

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-02-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:

AD 2000-08-22  MD Helicopters Inc.: Amendment 39-11708, Docket No. 
2000-SW-02-AD.

    Applicability: Model 369D, 369E, and 500N helicopters, with 
analog/digital turbine outlet temperature (TOT) indicator, part 
number (P/N) 369D24513-1, installed; and Model 600N helicopters, 
with analog/digital TOT indicator, P/N 9A3420, 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 (f) 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 an erroneous TOT indication, damage to critical 
engine components, loss of engine power, and a subsequent forced 
landing, accomplish the following:
    (a) For Model 369E, 369D, and 500N helicopters: Within the next 
50 hours time-in-service (TIS) or on or before June 15, 2000, 
whichever occurs first; test the TOT indicating system to verify 
correct calibration in accordance with the Accomplishment 
Instructions, Part I, of MD Helicopters, Inc. (MDHI) Service 
Bulletin SB369D-199, SB369E-093, SB500N-019, dated January 11, 2000 
(SB). Thereafter, repeat the test at intervals not to exceed 300 
hours TIS.
    (b) If during any test required by paragraph (a) of this AD the 
TOT indicator readings for the tester setting temperatures in Table 
1, Part I, of the SB are not within the indicator reading range, 
before further flight, perform the actions in the Accomplishment 
Instructions, Part I, paragraph (6)(b) of the SB.
    (c) For Model 600N helicopters: Within the next 50 hours TIS or 
on or before June 15, 2000, whichever occurs first; test the TOT 
indicating system, including the electronic control unit (ECU) TOT 
sensing system, to verify correct calibration in accordance with the 
Accomplishment Instructions, Part I, of MDHI SB600N-026, dated 
January 11, 2000 (SB 600N). Thereafter, repeat the test at intervals 
not to exceed 300 hours TIS.
    (d) If during any calibration test required by paragraph (c) of 
this AD the TOT indicator readings for the tester setting 
temperatures in Table 1, Part I, of SB 600N, are not within the 
indicator reading range, before further flight, perform the actions 
in the Accomplishment Instructions, Part I, paragraph (7)(b) of SB 
600N.
    (e) If during any test required by paragraph (c) of this AD the 
Full Authority Digital Electronic Control (FADEC) maintenance lap-
top terminal does not indicate ECU TOT within (5 degrees Celsius of 
the tester setting in Table 1, Part I, of SB 600N, before further 
flight, perform the actions in the Accomplishment Instructions, Part 
III, of the SB 600N.
    (f) 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, Los Angeles Aircraft Certification 
Office. Operators shall submit their requests through an FAA 
Principal Maintenance Inspector, who may concur or comment and then 
send it to the Manager, Los Angeles Aircraft Certification Office.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Los Angeles Aircraft Certification Office.

    (g) 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.
    (h) The tests shall be done in accordance with MD Helicopters 
Inc. Service Bulletin SB369D-199, SB369E-093, SB500N-019 for Model 
369D, 369E, and 500N helicopters and Service Bulletin SB600N-026 for 
Model 600N helicopters, both dated January 11, 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 MD Helicopters Inc., Attn: Customer 
Support Division, 4555 E. McDowell Rd., Mail Stop M615-GO48, Mesa, 
Arizona 85215-9797, telephone 1-800-388-3378 or 480-346-6387; 
datafax 480-346-6813. 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.
    (i) This amendment becomes effective on May 22, 2000.

    Issued in Fort Worth, Texas, on April 18, 2000.
Mark R. Schilling,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 00-11058 Filed 5-4-00; 8:45 am]
BILLING CODE 4910-13-U