[Federal Register Volume 63, Number 140 (Wednesday, July 22, 1998)]
[Proposed Rules]
[Pages 39252-39254]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-19458]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-140-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 repetitive tests to 
detect internal leakage of hydraulic fluid within the hydraulic 
components of the ground spoiler system and to detect a buildup of 
pressure in the return line of the bypass valve, and corrective action, 
if necessary; installation of additional hydraulic lines and an 
additional hydraulic shutoff valve in the ground spoiler system; and 
replacement of the valve block of the ground spoiler system with a new 
part. This proposal also would require eventual replacement of the 
relief restrictor valves of the ground spoiler system with redesigned 
parts, which would constitute terminating action for the repetitive 
tests. 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 the 
ground spoilers from unlocking and deploying during takeoff or in 
flight, and consequent reduced controllability of the airplane.

DATES: Comments must be received by August 21, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-140-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 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-140-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-140-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 
two conditions may lead to the uncommanded unlocking of the ground 
spoilers. First, a manufacturing defect in a certain batch of relief 
restrictor valves can lead to internal leakage of hydraulic fluid 
within the hydraulic components of the ground spoiler system. Second, 
the design of certain hydraulic components may cause the hydraulic 
system to be susceptible to the buildup of pressure in the hydraulic 
return line and in the bypass valve return line. These conditions, if 
not corrected, could result in the uncommanded unlocking and deployment 
of the ground spoilers during takeoff or in flight, and consequent 
reduced controllability of the airplane.

Explanation of Relevant Service Information

    Dornier has issued Service Bulletin SB-328-29-220, dated May 20, 
1997, and Revision 1, dated May 4, 1998, which describe procedures for 
performing repetitive tests to detect internal leakage of hydraulic 
fluid within the hydraulic components of the ground spoiler system and 
to detect a buildup of pressure in the return line of the bypass valve. 
These tests include: a major leakage test of the hydraulic components, 
a functional test of the return filter element, a functional test of 
the bypass valve of the return filter element, and a functional test of 
the shutoff valve with the bypass valve.
    Dornier has issued Service Bulletin SB-328-29-237, Revision 1, 
dated December 17, 1997, which describes procedures for installation of 
additional hydraulic lines and an additional hydraulic shutoff valve in 
the ground spoiler system.
    In addition, Dornier has issued Service Bulletin SB-328-27-243, 
Revision 1, dated December 18, 1997, which describes procedures for 
replacement of the relief restrictor valves of the ground spoiler 
system with redesigned parts, which would eliminate the need for the 
repetitive tests described previously.
    Dornier also has issued Service Bulletin SB-328-27-228, Revision 1, 
dated December 18, 1997, which describes procedures for replacement of 
the valve block of the ground spoiler system with a new part. 
Accomplishment of the actions specified in the service bulletins is

[[Page 39253]]

intended to adequately address the identified unsafe condition. The LBA 
classified these service bulletins as mandatory and issued German 
airworthiness directives 97-189, dated June 19, 1997; 1998-031, dated 
January 15, 1998; 1998-046, dated January 29, 1998; and 1997-331/2, 
dated March 12, 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 service bulletins described previously, 
except as discussed below.

Differences Between Proposed Rule and Service Bulletins

    Operators should note that Dornier Service Bulletins SB-328-29-220, 
dated May 20, 1997, and SB-328-29-220, Revision 1, dated May 4, 1998, 
do not specify corrective action for disposition of certain discrepant 
conditions. However, if any discrepancy is detected during the testing 
to detect internal leakage of hydraulic fluid within the hydraulic 
components of the ground spoiler system and to detect a buildup of 
pressure in the return line of the bypass valve, this proposal would 
require, prior to further flight, replacement of the relief restrictor 
valves of the ground spoiler system with a redesigned part, in 
accordance with Dornier Service Bulletin SB-328-27-243, Revision 1, 
dated December 18, 1997.

Cost Impact

    The FAA estimates that 11 airplanes of U.S. registry would be 
affected by this proposed AD.
    It would take approximately 3 work hours per airplane to accomplish 
the proposed tests, at an average labor rate of $60 per work hour. 
Based on these figures, the cost impact of the tests proposed by this 
AD on U.S. operators is estimated to be $180 per airplane, per test 
cycle.
    It would take approximately 16 work hours per airplane to 
accomplish the proposed installation, at an average labor rate of $60 
per work hour. Required parts would be supplied by the manufacturer at 
no cost to operators. Based on these figures, the cost impact of the 
installation proposed by this AD on U.S. operators is estimated to be 
$960 per airplane.
    It would take approximately 2 work hours per airplane to accomplish 
the proposed replacement of the relief restrictor valves, at an average 
labor rate of $60 per work hour. Required parts would be supplied by 
the manufacturer at no cost to operators. Based on these figures, the 
cost impact of this replacement proposed by this AD on U.S. operators 
is estimated to be $120 per airplane.
    It would take approximately 2 work hours per airplane to accomplish 
the proposed replacement of the valve block, at an average labor rate 
of $60 per work hour. Required parts would be supplied by the 
manufacturer at no cost to operators. Based on these figures, the cost 
impact of this replacement proposed by this AD on U.S. operators is 
estimated to be $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:

Dornier Luftfahrt GMBH: Docket 98-NM-140-AD.

    Applicability: Model 328-100 series airplanes, certificated in 
any category, equipped with active ground spoiler option 040-001; as 
listed in the following service bulletins:
     Dornier Service Bulletin SB-328-29-220, Revision 1, 
dated May 4, 1998;
     Dornier Service Bulletin SB-328-29-237, Revision 1, 
dated December 17, 1997;
     Dornier Service Bulletin SB-328-27-243, Revision 1, 
dated December 18, 1997; and
     Dornier Service Bulletin SB-328-27-228, Revision 1, 
dated December 18, 1997.

    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 (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 the ground spoilers from unlocking and deploying 
during takeoff or in flight, and consequent reduced controllability 
of the airplane, accomplish the following:

[[Page 39254]]

    (a) Prior to the accumulation of 3,000 total flight hours, or 
within 300 flight hours after the effective date of this AD, 
whichever occurs later: Perform tests to detect internal leakage of 
hydraulic fluid within the hydraulic components of the ground 
spoiler system and to detect a buildup of pressure in the return 
line of the bypass valve, in accordance with Dornier Service 
Bulletin SB-328-29-220, dated May 20, 1997, or Dornier Service 
Bulletin SB-328-29-220, Revision 1, dated May 4, 1998.
    (1) If no discrepancy is detected, repeat the tests thereafter 
at intervals not to exceed 3,000 flight hours, until accomplishment 
of the replacement required by paragraph (c) of this AD.
    (2) If any discrepancy is detected, prior to further flight, 
accomplish the replacement required by paragraph (c) of this AD.
    (b) Install additional hydraulic lines and an additional 
hydraulic shutoff valve in the ground spoiler system, in accordance 
with Dornier Service Bulletin SB-328-29-237, Revision 1, dated 
December 17, 1997, at the applicable time specified in either 
paragraph (b)(1) or (b)(2) of this AD.
    (1) For airplanes having serial numbers up to and including 
3086, equipped with ground spoiler actuator, part number 1059A0000-
02: Install within 12 months after the effective date of this AD.
    (2) For airplanes having serial numbers up to and including 
3086, and equipped with ground spoiler actuator, part number 
1059A0000-03: Install within 7 days after the effective date of this 
AD.
    (c) Replace the relief restrictor valves of the ground spoiler 
system, part number ZRV87-2, with a redesigned valve having part 
number ZRV87-3, in accordance with Dornier Service Bulletin SB-328-
27-243, Revision 1, dated December 18, 1997, at the applicable time 
specified in either paragraph (c)(1) or (c)(2) of this AD. 
Accomplishment of this replacement constitutes terminating action 
for the repetitive tests required by paragraph (a) of this AD.
    (1) For airplanes having serial numbers up to and including 
3098, equipped with ground spoiler actuator, part number 1059A0000-
02: Replace within 12 months after the effective date of this AD.
    (2) For airplanes having serial numbers up to and including 
3098, equipped with ground spoiler actuator, part number 1059A0000-
03: Replace within 7 days after the effective date of this AD.
    (d) Replace the valve block of the ground spoiler system with a 
new part, in accordance with Dornier Service Bulletin SB-328-27-228, 
Revision 1, dated December 18, 1997, at the applicable time 
specified in either paragraph (d)(1) or (d)(2) of this AD.
    (1) For airplanes having serial numbers up to and including 
3095, equipped with ground spoiler actuator, part number 1059A0000-
02: Replace within 12 months after the effective date of this AD.
    (2) For airplanes having serial numbers up to and including 
3095, equipped with ground spoiler actuator, part number 1059A0000-
03: Replace within 7 days after the effective date of this AD.
    (e) As of the effective date of this AD, no person shall install 
on the ground spoiler system of any airplane, a valve block, part 
number 1060A0000-05, or a relief restrictor valve, part number 
ZRV87-2.
    (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, 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 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

    (g) Special flight permits may be issued in accordance with 
Secs. 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 3: The subject of this AD is addressed in German 
airworthiness directives 97-189, dated June 19, 1997; 1998-031, 
dated January 15, 1998; 1998-046, dated January 29, 1998; and 1997-
331/2, dated March 12, 1998.

    Issued in Renton, Washington, on July 15, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-19458 Filed 7-21-98; 8:45 am]
BILLING CODE 4910-13-P