[Federal Register Volume 64, Number 161 (Friday, August 20, 1999)]
[Proposed Rules]
[Pages 45468-45470]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-21692]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-01-AD]
RIN 2120-AA64


Airworthiness Directives; Dornier Model 328-100 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 all Dornier Model 328-100 series 
airplanes. This proposal would require repetitive inspections of the 
left and right roll spoiler actuators to check for signs of leakage and 
deformation of the housing, repetitive inspections of the gap between 
the left roll spoiler actuator housing cap and the actuator housing, 
repetitive torque checks of the left roll spoiler actuator housing cap 
attachment screws, and corrective action, if necessary. 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 oil leakage from 
the roll spoiler actuators, which could result in incorrect roll 
spoiler operation and reduced controllability of the airplane.

DATES: Comments must be received by September 20, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-01-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

[[Page 45469]]

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 99-NM-01-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. 99-NM-01-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 all 
Dornier Model 328-100 series airplanes. The LBA advises that a fluid 
leakage from the roll spoiler actuator housing was found. Investigation 
showed that the existing design allowed the piston of the double 
shuttle valve to temporarily remain in the middle position, allowing 
high pressure to reach the low pressure side of the actuator. This 
resulted in deformation of the actuator housing cap and subsequent oil 
loss. This condition, if not corrected, could result in incorrect roll 
spoiler operation and reduced controllability of the airplane.

Explanation of Relevant Service Information

    Dornier has issued Alert Service Bulletin ASB-328-27-025, dated 
October 16, 1998, which describes procedures for repetitive detailed 
inspections of the left and right roll spoiler actuators for signs of 
leakage and deformation of the housing, repetitive inspections to 
detect a gap between the left roll spoiler actuator housing cap and the 
actuator housing, and repetitive torque checks of the left roll spoiler 
actuator housing cap attachment screws. The alert service bulletin also 
describes procedures for the replacement of the actuators and the 
double shuttle valves, if a gap or oil leakage is detected, if the cap 
surface is not flat, or if the torque of the attachment screws is less 
than 1 newton meter (8.85 lb-in).
    Both the left and right roll spoiler actuators are connected to the 
same double shuttle valve and experience the same hydraulic pressure. 
The left roll spoiler actuator is inspected more thoroughly, with the 
gap inspection and torque check, because it is more accessible than the 
right roll spoiler actuator. Removal of the right roll spoiler actuator 
from the airplane would be necessary to accomplish all inspection 
actions. In the event any discrepancy is noted on the left roll spoiler 
actuator requiring its replacement, the removal and complete inspection 
of the right roll spoiler actuator becomes necessary.
    Accomplishment of the actions specified in the alert service 
bulletin is intended to adequately address the identified unsafe 
condition. The LBA classified this alert service bulletin as mandatory 
and issued LBA airworthiness directive 1998-479, dated December 17, 
1998, 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 alert service bulletin described 
previously.
    This is considered to be interim action. The manufacturer has 
advised that it currently is developing a modification that will 
positively address the unsafe condition addressed by this AD. Once this 
modification is developed, approved, and available, the FAA may 
consider additional rulemaking.

Cost Impact

    The FAA estimates that 50 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 3 work 
hours per airplane to accomplish the proposed actions, and that the 
average labor rate is $60 per work hour. Based on these figures, the 
cost impact of the proposed AD on U.S. operators is estimated to be 
$9,000, or $180 per airplane, per inspection cycle.
    The cost impact figure discussed above is 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,

[[Page 45470]]

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 99-NM-01-AD.

    Applicability: All Dornier Model 328-100 series airplanes, 
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 (d) 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 oil leakage from the roll spoiler actuators, which 
could result in incorrect roll spoiler operation and reduced 
controllability of the airplane, accomplish the following:
    (a) Within 14 days after the effective date of this AD, 
accomplish the requirements of paragraphs (a)(1) and (a)(2) of this 
AD on the left and right roll spoiler actuators, in accordance with 
Dornier Alert Service Bulletin ASB-328-27-025, dated October 16, 
1998. Thereafter, repeat the inspections required by paragraphs 
(a)(1) and (a)(2) of this AD at intervals not to exceed 330 flight 
hours.
    (1) Perform a detailed inspection to detect leakage of the area 
around the actuator cap and housing of the roll spoiler actuators. 
If leakage is found, prior to further flight, replace the actuator 
and the double shuttle valve with new or serviceable parts.
    (2) Perform a detailed inspection to detect flatness of the 
surface of the cap of the roll spoiler actuators. If the cap surface 
is not flat, prior to further flight, replace the actuator and the 
double shuttle valve with new or serviceable parts.

    Note 2: For the purposes of this AD, a detailed inspection is 
defined as: ``An intensive visual examination of a specific 
structural area, system, installation, or assembly to detect damage, 
failure, or irregularity. Available lighting is normally 
supplemented with a direct source of good lighting at intensity 
deemed appropriate by the inspector. Inspection aids such as mirror, 
magnifying lenses, etc. may be used. Surface cleaning and elaborate 
access procedures may be required.''

    (b) Within 14 days after the effective date of this AD, 
accomplish the requirements of paragraphs (b)(1) and (b)(2) of this 
AD on the left roll spoiler actuator, in accordance with Dornier 
Alert Service Bulletin ASB-328-27-025, dated October 16, 1998. 
Thereafter, repeat the inspections required by paragraphs (b)(1) and 
(b)(2) of this AD at intervals not to exceed 330 flight hours.
    (1) Perform a detailed inspection to detect a gap between the 
cap of the roll spoiler actuator and the actuator housing. If any 
gap exists, prior to further flight, replace the actuator and the 
double shuttle valve with new or serviceable parts.
    (2) Perform a torque check of the housing cap attachment screws. 
If the torque is within the limits specified by the service 
bulletin, prior to further flight, torque the screws to 17.7 lb-in, 
in accordance with the alert service bulletin. If the torque is 
outside the limits specified by the service bulletin, prior to 
further flight, replace the left roll spoiler actuator and double 
shuttle valve with new or serviceable parts, in accordance with the 
alert service bulletin.
    (c) If any left roll spoiler actuator is replaced during any 
inspection required by paragraph (b)(1) or (b)(2) of this AD, prior 
to further flight, accomplish the requirements of (b)(1) and (b)(2) 
for the right roll spoiler actuator.

Alternate Methods of Compliance

    (d) 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.

Special Flight Permits

    (e) 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 LBA airworthiness 
directive 1998-479, dated December 17, 1998.

    Issued in Renton, Washington, on August 16, 1999.
D. L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-21692 Filed 8-19-99; 8:45 am]
BILLING CODE 4910-13-U