```
[Federal Register Volume 63, Number 97 (Wednesday, May 20, 1998)]
[Proposed Rules]
[Pages 27688-27690]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-13391]

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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-149-AD]
RIN 2120-AA64

Airworthiness Directives; Aerospatiale Model ATR42 and ATR72 
Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain Aerospatiale Model ATR42 
and

[[Page 27689]]

ATR72 series airplanes. This proposal would require a one-time 
inspection of the electromagnetic interference (EMI) filter capacitors 
and electronic cards of the cabin air recirculation fans to detect 
damage. This proposal also would require replacement of damaged 
components with new or serviceable parts, and modification of the cabin 
air assembly fans. 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 and consequent failure of the EMI filter 
capacitors, which could result in emission of toxic smoke and fumes 
throughout the airplane, and consequent adverse effects on flight crew 
and passengers.

DATES: Comments must be received by June 19, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-149-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 Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 
03, France. This information may be examined at the 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-NM-149-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-149-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Direction Generale de l'Aviation Civile (DGAC), which is the 
airworthiness authority for France, notified the FAA that an unsafe 
condition may exist on certain Aerospatiale Model ATR42 and ATR72 
series airplanes. The DGAC advises that it has received several reports 
of toxic smoke and fumes emitting into the passenger compartments. 
Investigation revealed that the toxic smoke and fumes resulted from 
excess thermal stress (overheating) of the electromagnetic interference 
(EMI) filter capacitors on the electronic cards of the cabin air 
recirculation fans, which are associated with the right and left air-
conditioning packs. The overheated EMI filter capacitors leaked 
electrolyte onto the electronic cards of the air recirculation fans. 
The electrolyte leakage caused short-circuiting, charring, and 
corrosion of the electronic cards, emitting toxic smoke into the 
passenger compartments. Such overheating and consequent failure of the 
EMI filter capacitors, if not corrected, could result in emission of 
toxic smoke and fumes throughout the airplane, and consequent adverse 
effects on flight crew and passengers.

Explanation of Relevant Service Information

    The manufacturer has issued Avions de Transport Regional Service 
Bulletins ATR42-21-0069, dated February 5, 1998 (for Model ATR42 series 
airplanes), and ATR72-21-1048, dated February 5, 1998 (for Model ATR72 
series airplanes), which describe procedures for performing a one-time 
visual inspection to detect damage of the EMI filter capacitors and 
electronic cards of the cabin air recirculation fans of the left and 
right air-conditioning packs. The service bulletins also describe 
procedures for replacement of damaged components with new or 
serviceable parts, and modification of the cabin air assembly fans. 
Accomplishment of the actions specified in the service bulletins are 
intended to adequately address the identified unsafe condition. The 
DGAC classified these service bulletins as mandatory and issued French 
airworthiness directive 98-070-074(B) (for Model ATR42 series 
airplanes) and 98-073-037(B) (for Model ATR72 series airplanes), both 
dated February 11, 1998, in order to assure the continued airworthiness 
of these airplanes in France.
    Avions de Transport Regional Service Bulletins reference EG&G 
Rotron Service Bulletin 011232500-21-1, dated December 12, 1997, as an 
additional source of service information for accomplishment of the 
modification.

FAA's Conclusions

    These airplane models are manufactured in France 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 DGAC has kept the FAA informed 
of the situation described above. The FAA has examined the findings of 
the DGAC, 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 service bulletins described previously.

Interim Action

    This is considered to be interim action until final action is 
identified, at which time the FAA may consider additional rulemaking.

Cost Impact

    The FAA estimates that 81 airplanes of U.S. registry would be 
affected by this

[[Page 27690]]

proposed AD, that it would take approximately 3 work hours 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 the 
inspection proposed by this AD on U.S. operators is estimated to be 
$14,580, or $180 per airplane.
    It would take approximately 2 work hours per airplane to accomplish 
the proposed modification at an average labor rate of $60 per work 
hour. The cost of the required parts would be minimal. Based on these 
figures, the cost impact of the modification proposed by this AD on 
U.S. operators is estimated to be $9,720, or $120 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.
    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:

Aerospatiale: Docket 98-NM-149-AD.

    Applicability: Model ATR42-300, -320, and -500 series airplanes, 
as listed in Aerospatiale Service Bulletin ATR42-21-0069, dated 
February 5, 1998; and Model ATR72-101, -102, -201, -202, -211, -212, 
and -212A series airplanes, as listed in Aerospatiale Service 
Bulletin ATR72-21-1048, dated February 5, 1998; 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 and consequent failure of the 
electromagnetic interference (EMI) filter capacitors, which could 
result in emission of toxic smoke and fumes throughout the airplane, 
and consequent adverse effects on flight crew and passengers, 
accomplish the following:
    (a) Within 11 months after the effective date of this AD, 
perform a one-time visual inspection to detect damage of the EMI 
filter capacitors and electronic cards of the cabin air 
recirculation fan of the right and left air-conditioning packs, in 
accordance with Avions de Transport Regional Service Bulletin ATR42-
21-0069, dated February 5, 1998 (for Model ATR42 series airplanes), 
or ATR72-21-1048, dated February 5, 1998 (for Model ATR72 series 
airplanes), as applicable.
    (1) If no discrepancy is detected, prior to further flight, 
modify and re-identify each fan assembly, in accordance with the 
applicable service bulletin.
    (2) If any discrepancy is detected, prior to further flight, 
replace the damaged components with new or serviceable components, 
and modify and re-identify the fan assembly, in accordance with the 
applicable service bulletin.

    Note 2: Avions de Transport Regional Service Bulletin ATR42-21-
0069, dated February 5, 1998 (for Model ATR42 series airplanes), and 
ATR72-21-1048, dated February 5, 1998 (for Model ATR72 series 
airplanes), reference EG&G Rotron Service Bulletin 011232500-21-1, 
dated December 12, 1997, as an additional source of service 
information for accomplishment of the modification.

    (b) As of the effective date of this AD, no person shall install 
on any airplane a cabin air-conditioning recirculation Rotron fan 
having part number (P/N) 011232500 Amend. A, or P/N 011494500 Amend. 
A, on the left or right air-conditioning pack.
    (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 French 
airworthiness directives 98-070-074(B) and 98-073-037(B), both dated 
February 11, 1998.

    Issued in Renton, Washington, on May 14, 1998.
John J. Hickey,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-13391 Filed 5-19-98; 8:45 am]
BILLING CODE 4910-13-U
```