[Federal Register Volume 63, Number 129 (Tuesday, July 7, 1998)]
[Proposed Rules]
[Pages 36624-36626]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-17957]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-96-AD]
RIN 2120-AA64


Airworthiness Directives; Dornier Model 328-100 Series Airplanes

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) that is applicable to certain Dornier Model 328-100 
series airplanes. This proposal would require a one-time inspection of 
direct current (DC) power unit 1VE to determine whether electrical 
connections are correctly installed and stud nuts are correctly 
torqued, and corrective actions, if necessary. For certain airplanes, 
this proposal also would require replacement of the existing DC power 
unit 1VE with a modified DC power unit. This proposal is prompted by 
issuance of mandatory continuing airworthiness information by a foreign 
civil airworthiness authority. The actions specified by the proposed AD 
are intended to prevent overheating of electrical connections, which 
could result in electrical arcing and consequent fire.

DATES: Comments must be received by August 6, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-96-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056. Comments may be inspected at this location 
between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal 
holidays.
    The service information referenced in the proposed rule may be 
obtained from FAIRCHILD DORNIER, DORNIER Luftfahrt GmbH, P.O. Box 1103, 
D-82230 Wessling, Germany. This information may be examined at the

[[Page 36625]]

FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2110; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION:

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 shall 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 Number 98-M-96-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, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket No. 98-NM-96-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority 
for Germany, notified the FAA that an unsafe condition may exist on 
certain Dornier Model 328-100 series airplanes. The LBA advises that it 
has received reports of overheating of the electrical connection studs 
on direct current (DC) power unit 1VE, which has been attributed to 
incorrectly installed terminals and spring washers, and incorrect 
torquing of the stud nuts. The LBA also has received reports of 
overheating and burning of the mounting plate of the bus bar of the 
auxiliary power unit in the DC power unit 1VE, which have been 
attributed to an incorrectly torqued bus bar screw. Such overheating of 
electrical connections, if not corrected, could result in electrical 
arcing and consequent fire.

Explanation of Relevant Service Information

    The manufacturer has issued Dornier Alert Service Bulletin ASB-328-
24-018, dated August 5, 1997. The alert service bulletin describes 
procedures for a one-time visual inspection of the electrical 
connections of DC power unit 1VE to determine whether terminals and 
spring washers are installed correctly, and a one-time torque 
inspection of the stud nuts to determine whether they are torqued 
correctly. Figure 1 and Table 1 of this alert service bulletin specify 
criteria for ensuring correct installation of the terminals and spring 
washers and correct torquing of the stud nuts.
    The manufacturer also has issued Dornier Alert Service Bulletin 
ASB-328-24-021, dated November 25, 1997, which describes procedures for 
removing DC power unit 1VE and installing a modified DC power unit. 
Dornier Alert Service Bulletin ASB-328-24-021 refers to l'Equipement et 
la Construction Electrique (ECE) Alert Service Bulletin ASB 230GC02Y-
24-001, dated November 24, 1997, as an additional source of service 
information for accomplishing the modification of the DC power unit. 
That ECE alert service bulletin describes procedures for inspecting the 
glass mounting plate of the auxiliary power unit (APU) bus bar in the 
DC power unit 1VE for heat damage, installing a shim, and performing a 
one-time inspection of the APU bus bar screw to ensure that it is 
correctly torqued.
    Accomplishment of the actions specified in the Dornier alert 
service bulletins is intended to adequately address the identified 
unsafe condition. The LBA classified these Dornier alert service 
bulletins as mandatory and issued German airworthiness directive 97-
322, dated November 20, 1997, and German airworthiness directive 97-
354, dated December 18, 1997, in order to assure the continued 
airworthiness of these airplanes in Germany.

FAA's Conclusions

    This airplane model is manufactured in Germany and is 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 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.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, the proposed AD would require accomplishment of 
the actions specified in the Dornier alert service bulletins described 
previously.

Cost Impact

    The FAA estimates that 50 airplanes of U.S. registry would be 
affected by this proposed AD.
    It would take approximately 1 work hour per airplane to accomplish 
the proposed inspection, at an average labor rate of $60 per work hour. 
Based on these figures, the cost impact of this proposed inspection on 
U.S. operators is estimated to be $3,000, or $60 per airplane.
    It would take approximately 4 work hours per airplane to accomplish 
the proposed replacement, at an average labor rate of $60 per work 
hour. Required parts would be provided by the manufacturer at no cost 
to the operators. Based on these figures, the cost impact of this 
proposed replacement on U.S. operators is estimated to be $12,000, or 
$240 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the proposed requirements 
of this AD action, and that no operator would accomplish those actions 
in the future if this AD were not adopted.

Regulatory Impact

    The regulations proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.

[[Page 36626]]

    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 the following new 
airworthiness directive:

    Dornier Luftfahrt GmbH: Docket 98-NM-96-AD.

    Applicability: Model 328-100 series airplanes, as listed in 
Dornier Alert Service Bulletin ASB-328-24-021, dated November 25, 
1997; or Dornier Alert Service Bulletin ASB-328-24-018, dated August 
5, 1997; certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes 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 overheating of electrical connections, which could 
result in electrical arcing and consequent fire, accomplish the 
following:
    (a) For airplanes listed in Dornier Alert Service Bulletin ASB-
328-24-018, dated August 5, 1997: Within 10 days after the effective 
date of this AD, perform the actions required by paragraphs (a)(1) 
and (a)(2) of this AD, in accordance with Dornier Alert Service 
Bulletin ASB-328-24-018, dated August 5, 1997.
    (1) Perform a one-time visual inspection of direct current (DC) 
power unit 1VE to determine whether electrical connections are 
installed correctly, in accordance with the Accomplishment 
Instructions of the alert service bulletin. If any discrepancy is 
detected, prior to further flight, install the connections in 
accordance with Figure 1 of the alert service bulletin.
    (2) Perform a one-time torque inspection of the stud nuts of DC 
power unit 1VE to determine whether they are torqued correctly, in 
accordance with the Accomplishment Instructions of the alert service 
bulletin. If any discrepancy is found, prior to further flight, 
torque in accordance with Table 1 of the alert service bulletin.
    (b) For airplanes listed in Dornier Alert Service Bulletin ASB-
328-24-021, dated November 25, 1997: Within 10 days after the 
effective date of this AD, replace the existing DC power unit 1VE 
with a modified DC power unit, in accordance with Dornier Alert 
Service Bulletin ASB-328-24-021, dated November 25, 1997.

    Note 2: Dornier Alert Service Bulletin 328-24-021, dated 
November 25, 1997, refers to l'Equipement et la Construction 
Electrique Alert Service Bulletin ASB 230GC02Y-24-001, dated 
November 24, 1997, as an additional source of service information 
for accomplishing the modification of the DC power unit.

    (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, International Branch, ANM-116, FAA, 
Transport Airplane Directorate. Operators shall submit their 
requests through an appropriate FAA Principal Maintenance Inspector, 
who may add comments and then send it to the Manager, International 
Branch, ANM-116.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

    (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 airplane to a location where 
the requirements of this AD can be accomplished.

    Note 4: The subject of this AD is addressed in German 
airworthiness directive 97-322, dated November 20, 1997; and German 
airworthiness directive 97-354, dated December 18, 1997.

    Issued in Renton, Washington, on June 30, 1998.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-17957 Filed 7-6-98; 8:45 am]
BILLING CODE 4910-13-P