[Federal Register Volume 69, Number 63 (Thursday, April 1, 2004)]
[Proposed Rules]
[Pages 17097-17101]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-7303]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NM-294-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 supersedure of an existing 
airworthiness directive (AD), applicable to all Dornier Model 328-100 
series airplanes, that currently requires certain revisions to the 
airplane flight manual, replacement of certain de-icing boots in the 
air intake duct assemblies of the engine with re-designed units, 
repetitive inspections of the boots to find discrepancies, and 
corrective action if necessary. This action would also require 
modification of the engine air inlet de-icing system. This action would 
extend the repetitive inspection interval required by the existing AD, 
and would add repetitive debonding/delamination and leakage inspections 
of the de-icing boots, and corrective action if necessary. Initiation 
of the extended repetitive inspections and new repetitive inspections 
would end the repetitive inspections required by the existing AD. The 
actions specified by the proposed AD are intended to prevent engine 
malfunction due to failure of the engine air inlet de-icing system, 
which could result in reduced controllability of the airplane. This 
action is intended to address the identified unsafe condition.

DATES: Comments must be received by May 3, 2004.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2002-NM-294-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9 a.m. and 3 p.m., Monday through Friday, except 
Federal holidays. Comments may be submitted via fax to (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2002-NM-294-AD'' in the subject line and need not 
be submitted in triplicate. Comments sent via the Internet as attached 
electronic files must be formatted in Microsoft Word 97 or 2000 or 
ASCII text.
    The service information referenced in the proposed rule may be 
obtained from AvCraft Aerospace 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: Tom Groves, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-1503; 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 action may be changed in 
light of the comments received.
    Submit comments using the following format:
     Organize comments issue-by-issue. For example, 
discuss a request to change the compliance time and a request to change 
the service bulletin reference as two separate issues.
     For each issue, state what specific change to 
the proposed AD is being requested.
     Include justification (e.g., reasons or data) 
for each request.
    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

[[Page 17098]]

submitted in response to this action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2002-NM-294-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. 2002-NM-294-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On March 14, 1995, the FAA issued AD 95-04-51, amendment 39-9179 
(60 FR 15037, March 22, 1995), applicable to all Dornier Model 328-100 
series airplanes, to require certain revisions to the airplane flight 
manual (AFM), replacement of certain de-icing boots in the air intake 
duct assemblies of the engine with re-designed units, and inspections 
of the boots to find discrepancies. That action was prompted by reports 
of failures of the engine air inlet de-icing system, including 
debonding of the boots from the engine air intake ducts, failure of the 
air-tight chambers in the boots, and malfunction and subsequent 
shutdown of an engine during flight. The requirements of that AD are 
intended to prevent engine malfunction due to failure of the engine air 
inlet de-icing system.

Actions Since Issuance of Previous Rule

    In the preamble to AD 95-04-51, we specified that the actions 
required by that AD were considered to be ``interim action'' and that 
we may consider further rulemaking action. The manufacturer now has 
developed an improved modification of the engine air inlet de-icing 
system. We have determined that further rulemaking is necessary to 
require the modification on affected airplanes; this proposed AD 
follows from that determination.

Explanation of New Service Information

    The manufacturer has issued the following Dornier Service 
Bulletins:
     SB-328-71-122, Revision 1, dated May 10, 1999, 
which describes procedures for the modification of the engine air 
intake ducts. The service bulletin references Westland Aerospace 
Limited Service Bulletin SB-WAL328-71-122, dated September 25, 1995, as 
an additional source of service information for accomplishment of the 
modification.
     SB-328-71-125, Revision 3, dated May 10, 1999, 
which describes procedures for modification of the engine air inlet de-
icing system, which includes installation of new, improved engine air 
intake ducts, installation of geometrically adapted de-icing boots, and 
installation of an improved outlet cover plate of the bypass duct. The 
service bulletin also describes procedures for doing detailed visual 
and tactile inspections of certain de-icing boots for discrepancies 
(flat spots, softness, or other irregularities in concave sections, or 
improper sealing), and corrective action if discrepancies are found. 
The corrective action includes doing a debonding inspection, as 
specified in the airplane maintenance manual, and if the debonded area 
is outside the allowable limits, replacing all three de-icing boots 
before further flight.
    Dornier Service Bulletin SB-328-71-125, Revision 3, also references 
Westland Aerospace Limited Service Bulletin SB-WAL328-71-125, Revision 
1, dated September 25, 1995, as an additional source of service 
information for installation of the cover plate of the bypass duct 
outlet.
     SB-328-30-432, dated April 26, 2002, which 
describes procedures for doing detailed visual and tactile inspections 
of the engine air inlet de-icing boots to find discrepancies (flat or 
soft spots in concave sections, defects on the de-icing boots, or 
improper sealing), and corrective action if discrepancies are found. 
The corrective action includes doing a debonding/delamination and 
leakage inspection, and replacing any delaminated de-icing boot outside 
the allowable bonding limits. The inspections are to be repeated 
thereafter at certain intervals.
    The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority 
for Germany, classified the Dornier service information as mandatory 
and issued German airworthiness directives 1995-156/3, dated July 1, 
1999; and 2002-256, dated September 5, 2002, to ensure 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 us informed of the 
situation described above. We have 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 supersede AD 95-04-51 to 
continue to require the revisions to the AFM, replacement of certain 
de-icing boots in the air intake duct assemblies of the engine with re-
designed units, and repetitive inspections of the boots to find 
discrepancies, and corrective action if necessary. This action also 
would require modification of the engine air inlet de-icing system and 
would add a new AFM revision which changes the compliance time for the 
functional test required by the existing AD. It would also extend the 
repetitive inspection interval required by the existing AD, and would 
add repetitive debonding/delamination and leakage inspections of the 
de-icing boots, and corrective action if necessary. Initiation of the 
extended repetitive inspections and debonding/delamination and leakage 
inspections would end the repetitive inspections required by the 
existing AD. The actions would be required to be accomplished in 
accordance with the Dornier service bulletins described previously, 
except as discussed below.

Differences Among German Airworthiness Directives, Dornier Service 
Bulletins, and Proposed AD

    The German airworthiness directives do not contain a requirement 
for continued accomplishment of the functional test required by the 
existing AD, but this proposed AD does continue to require 
accomplishment of the functional test.
    German airworthiness directive 2002-256 and Service Bulletin SB-
328-30-432 specify a repetitive interval of 800 flight hours for the 
detailed inspection and a debonding/delamination and leakage inspection 
of the engine air intake de-icing system specified in paragraph 2.B.2. 
of the service bulletin. We have determined that, since paragraph 
2.B.1.(1) of the service bulletin specifies the same detailed 
inspection at a 60-flight-hour interval, it is not necessary to also 
require the detailed inspection at the 800-flight-hour interval.
    In addition, this proposed AD would require accomplishment of the 
debonding/delamination and leakage inspection described in paragraph 
2.B.2.(2) of the service bulletin at intervals not to exceed 400 flight 
hours,

[[Page 17099]]

in lieu of every 800 flight hours. We have reviewed the service history 
of the U.S.-registered fleet of Model 328-100 series airplanes and have 
found that an 800-flight-hour debonding/delamination and leakage 
inspection interval would not be sufficient to find progressive inlet 
boot delamination/debonding before it reaches a point where it 
represents a hazard to the airplane. In developing an appropriate 
compliance time for this action, we considered not only the safety 
implications and the LBA recommendations, but the manufacturer's 
recommendation and the degree of urgency associated with addressing the 
subject unsafe condition. In light of all of these factors, we find an 
initial compliance time of ``within 400 flight hours after the 
effective date of this AD,'' and repetitive intervals not to exceed 400 
flight hours after the initial inspection, for doing the proposed 
debonding/delamination and leakage inspections to be warranted, in that 
those times represent appropriate intervals of time allowable for 
affected airplanes to continue to operate without compromising safety.
    Although Service Bulletin SB-328-30-432 defines the inspection as 
``visual'' and ``touch,'' and SB-328-71-125 defines the inspection as 
``detailed visual'' and ``tactile,'' this proposed AD defines that 
inspection as a ``detailed'' inspection. In addition, we have changed 
all references to a ``detailed visual inspection'' in the existing AD 
to ``detailed inspection'' in this proposed AD. A new note has been 
added to the proposed AD to define this inspection.
    German airworthiness directive 1995-156/3 and Service Bulletin SB-
328-71-125 recommend modification of the air intake/de-icing system 
``not later than December 31, 1995,'' and ``weekly'' visual and tactile 
inspections. This proposed AD would require the modification within 60 
flight hours after the effective date of this AD. When German 
airworthiness directive 1995-156/2 was issued on November 2, 1995, we 
did not take parallel action because we had previously issued an 
alternative method of compliance for the existing AD which approved the 
modification of the air intake/de-icing system. We are now requiring 
the modification on all airplanes that have not yet been modified.
    In addition, although ``weekly'' visual and tactile inspections are 
specified in the German airworthiness directive and Service Bulletin 
SB-328-71-125, this proposed AD would require only a one-time 
inspection after accomplishment of the modification, then repetitive 
detailed inspections at intervals not to exceed 60 flight hours and 
debonding/delamination and leakage inspections at intervals not to 
exceed 400 flight hours, per the procedures specified in Service 
Bulletin SB-328-30-432.
    Service Bulletin SB-328-30-432 describes procedures for completing 
a reporting sheet with inspection results, but this proposed AD does 
not include such a requirement.

Work Hour Rate Increase

    We have reviewed the figures we have used over the past several 
years to calculate AD costs to operators. To account for various 
inflationary costs in the airline industry, we find it necessary to 
increase the labor rate used in these calculations from $60 per work 
hour to $65 per work hour. The cost impact information, below, reflects 
this increase in the specified hourly labor rate.

Cost Impact

    There are about 53 airplanes of U.S. registry that would be 
affected by this proposed AD.
    The AFM revision currently required by AD 95-04-51 takes about 1 
work hour per airplane to accomplish, at an average labor rate of $65 
per work hour. Based on these figures, the cost impact of the currently 
required AFM revision is estimated to be $65 per airplane.
    The inspections currently required by AD 95-04-51 take about 1 work 
hour per airplane to accomplish, at an average labor rate of $65 per 
work hour. Based on these figures, the cost impact of the currently 
required inspections are estimated to be $65 per airplane, per 
inspection cycle.
    The replacement currently required by AD 95-04-51 takes about 5 
work hours per airplane to accomplish, at an average labor rate of $65 
per work hour. Required parts will cost about $55,000 per airplane. 
Based on these figures, the cost impact of the currently required 
replacement is estimated to be $55,325 per airplane.
    The modification proposed in this AD action would take about 10 
work hours per airplane to accomplish, at an average labor rate of $65 
per work hour. Required parts would be free of charge. Based on these 
figures, the cost impact of the proposed modification on U.S. operators 
is estimated to be $34,450, or $650 per airplane.
    The inspection/debonding/delamination and leakage inspection 
proposed in this AD action would take about 1 work hour per airplane to 
accomplish, at an average labor rate of $65 per work hour. Based on 
these figures, the cost impact of the proposed inspection on U.S. 
operators is estimated to be $3,445, or $65 per airplane, per 
inspection cycle.
    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. The cost impact figures 
discussed in AD rulemaking actions represent only the time necessary to 
perform the specific actions actually required by the AD. These figures 
typically do not include incidental costs, such as the time required to 
gain access and close up, planning time, or time necessitated by other 
administrative actions.

Regulatory Impact

    The regulations proposed herein would 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 proposal would not have federalism implications 
under Executive Order 13132.
    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.

[[Page 17100]]

Sec.  39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-9179 (60 FR 
15037, March 22, 1995), and by adding a new airworthiness directive 
(AD), to read as follows:

Fairchild Dornier GmbH (Formerly Dornier Luftfahrt GmbH): Docket 
2002-NM-294-AD. Supersedes AD 95-04-51, Amendment 39-9179.

    Applicability: All Model 328-100 airplanes, certificated in any 
category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent engine malfunction due to failure of the engine air 
inlet de-icing system, which could result in reduced controllability 
of the airplane, accomplish the following:

Restatement of Certain Requirements of AD 95-04-01

AFM Revision

    (a) For all airplanes: Within 24 hours after April 6, 1995 (the 
effective date of AD 95-04-51, amendment 39-9179), accomplish 
paragraphs (a)(1), (a)(2), and (a)(3) of this AD.
    (1) Revise the Limitations Section of the FAA-approved Airplane 
Flight Manual (AFM) by inserting the following limitation in the 
AFM. This may be accomplished by inserting a copy of this AD in the 
AFM.
    ``During flight, if the `ENG DEICE FAIL' electronic indication 
and caution advisory system (EICAS) annunciation activates for 
either engine, flight into known or forecast icing conditions is 
prohibited.''
    (2) Revise the Abnormal Procedures Section of the FAA-approved 
AFM by removing page 4, dated September 1, 1994, of section 04-12-
00, and replacing it with the following. This may be accomplished by 
inserting a copy of this AD in the AFM.

``1. Icing Conditions....................  Exit immediately.
                                           If unable, land at nearest
                                            suitable airport.''
 

    (3) Revise the Limitations Section of the FAA-approved AFM to 
include the following functional test. This may be accomplished by 
inserting a copy of this AD in the AFM. Continue to do the 
functional test until the AFM revision required by paragraph (e) of 
this AD is done.
    ``Accomplish the following test at the applicable time specified 
as follows:
    For airplanes equipped with air intake duct assemblies having 
de-icing boots with part numbers (P/N's) 29S-5D5240-21, -23, and -
25: As of 24 hours after the effective date of AD 95-04-51, 
accomplish the functional test prior to each flight.
    For airplanes equipped with air intake duct assemblies having 
de-icing boots with P/N's 29S-5D5240-211 (inlet lip), -231 (bypass 
duct), and -251 (aft ramp duct): Accomplish the functional test 
within 24 hours after the effective date of AD 95-04-51, and 
thereafter at daily intervals.
    Perform a functional test of the de-icing system of the air 
intake ducts of the left and right engines to determine the 
condition of the system, in accordance with the procedures specified 
below. Flight crew or maintenance personnel shall perform this test.

FUNCTIONAL TEST OF THE DE-ICING SYSTEM

    With engines running at idle power, display and monitor the `ICE 
PROTECT' system page of the electronic indication and caution 
advisory system (EICAS), select left and right `ENGINE INTAKE' 
pushbuttons in (`ON'), for a minimum of 60 seconds. Monitor system 
page for normal indications of one complete boot inflation and 
deflation cycle. Monitor EICAS for normal messages, and absence of 
`ENG DEICE FAIL' caution.
    After 60 seconds and observation of one complete inflation/
deflation cycle, release `ENGINE INTAKE' pushbuttons to out (`OFF') 
position, confirm absence of system page and EICAS cautions, and 
deselect `ICE PROTECT' system page. At completion of check, `ENGINE 
INTAKE' pushbuttons may be turned back on if required for departure.
    If any EICAS `ENG DEICE FAIL' annunciation is observed, or if 
system normal inflate and deflate cycling is not observed: The 
system shall be considered inoperative. Prior to further flight, the 
detailed visual and tactile inspections required by paragraph (b) of 
AD 95-04-51 must be accomplished.
    If no discrepancy with the de-icing boots is found during these 
inspections, the de-icing system may be inoperative for a period of 
time not to exceed that specified in the DO-328 Master Minimum 
Equipment List (MMEL). Flight into known or forecast icing 
conditions is prohibited.''

Repetitive Inspections/Corrective Action

    (b) For airplanes equipped with air intake duct assemblies 
having de-icing boots with part numbers (P/N) 29S-5D5240-21, -23, 
and -25: Accomplish paragraphs (b)(1) and (b)(2) of this AD at the 
times specified in those paragraphs.
    (1) Within 24 hours after April 6, 1995: Perform a detailed 
inspection and a tactile inspection of the de-icing boots in the air 
intake ducts on the engines to find flat spots, softness, or other 
discrepancies, and to ensure that the edges of the de-icing boots 
are sealed properly, in accordance with Dornier Service Bulletin SB-
328-30-020, dated March 17, 1994.

    Note 1: 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.''

    (i) If no discrepancies are found and the edges of the de-icing 
boots are sealed properly (no debonding between the boot and the 
intake duct), repeat the detailed and tactile inspections required 
by paragraph (b)(1) of this AD thereafter at daily intervals until 
accomplishment of the modification required by paragraph (f) of this 
AD.
    (ii) If any discrepancy is found, or if any edge of a de-icing 
boot is sealed improperly (debonding between the boots and the 
intake duct), prior to further flight, replace all three de-icing 
boots having P/Ns 29S-5D5240-21, -23, and -25, with three new units 
having P/Ns 29S-5D5240-211, -231, and -251, in accordance with the 
procedures specified in Dornier Alert Service Bulletin ASB-328-71-
006, Revision 1, dated February 16, 1995.
    (2) Within 5 days after April 6, 1995, replace all three de-
icing boots having P/N's 29S-5D5240-21, -23, and -25, with three new 
units having P/Ns 29S-5D5240-211, -231, and -251, in accordance with 
Dornier Alert Service Bulletin ASB-328-71-006, Revision 1, dated 
February 16, 1995. Following such replacement, perform the detailed 
and tactile inspections and the functional tests required by 
paragraphs (c) and (e) of this AD, respectively, in accordance with 
the times and procedures specified in those paragraphs.
    (c) For airplanes equipped with air intake duct assemblies 
having de-icing boots with P/Ns 29S-5D5240-211,-231, and -251: 
Within 7 days after April 6, 1995, perform a detailed inspection and 
a tactile inspection of the de-icing boots in the air intake ducts 
on the engines to find flat spots, softness, or other discrepancies, 
and to ensure that the edges of the de-icing boots are sealed 
properly, in accordance with the procedures specified in Dornier 
Service Bulletin SB-328-30-020, dated March 17, 1994.
    (1) If no discrepancies are found and the edges of the de-icing 
boots are sealed properly (no debonding between the boot and the 
intake duct): Repeat the detailed and tactile inspections required 
by paragraph (c) of this AD thereafter at intervals not to exceed 7 
days until accomplishment of the modification required by paragraph 
(f) of this AD.
    (2) If any discrepancy is found, or if any edge of a de-icing 
boot is sealed improperly (debonding between the boots and the 
intake duct): Prior to further flight, replace all three de-icing 
boots with three new units having P/Ns 29S-5D5240-211, -231, and -
251, in accordance with Dornier Alert Service Bulletin ASB-328-71-
006, Revision 1, dated February 16, 1995.

Parts Installation

    (d) As of April 6, 1995, no de-icing boot having P/N 29S-5D5240-
21, -23, or -25 shall be installed on any airplane.

New Requirements of This Ad

AFM Revision

    (e) Within 24 hours after the effective date of this AD: Revise 
the Limitations Section of the AFM to include the following 
functional test. This may be accomplished by inserting a copy of 
this AD into the AFM. Accomplishment of this paragraph ends the 
requirements of paragraph (a)(3) of this AD, and the AFM revision 
required by that paragraph may be removed from the AFM.
    ``Accomplish the following test within 24 hours after the 
effective date of this AD. Repeat the test thereafter at daily 
intervals.
    Perform a functional test of the de-icing system of the air 
intake ducts of the left and right engines to determine the 
condition of the system, in accordance with the procedures specified 
below. Flight crew or

[[Page 17101]]

maintenance personnel shall perform this test.

FUNCTIONAL TEST OF THE DE-ICING SYSTEM

    With engines running at idle power, display and monitor the `ICE 
PROTECT' system page of the electronic indication and caution 
advisory system (EICAS), select left and right `ENGINE INTAKE' 
pushbuttons in (`ON'), for a minimum of 60 seconds. Monitor system 
page for normal indications of one complete boot inflation and 
deflation cycle. Monitor EICAS for normal messages, and absence of 
`ENG DEICE FAIL' caution.
    After 60 seconds and observation of one complete inflation/
deflation cycle, release `ENGINE INTAKE' pushbuttons to out (`OFF') 
position, confirm absence of system page and EICAS cautions, and 
deselect `ICE PROTECT' system page. At completion of check, `ENGINE 
INTAKE' pushbuttons may be turned back on if required for departure.
    If any EICAS `ENG DEICE FAIL' annunciation is observed, or if 
system normal inflate and deflate cycling is not observed: The 
system shall be considered inoperative. Prior to further flight, the 
detailed inspections required by paragraph (g) of this AD must be 
accomplished.
    If no discrepancy with the de-icing boots is found during these 
inspections, the de-icing system may be inoperative for a period of 
time not to exceed that specified in the DO-328 Master Minimum 
Equipment List (MMEL). Flight into known or forecast icing 
conditions is prohibited.''

Modification of the Engine Air Intake De-icing System

    (f) Within 60 flight hours after the effective date of this AD: 
Modify the engine air inlet de-icing system (including a one-time 
detailed inspection and a debonding/delamination and leakage 
inspection) by doing all the actions (including any applicable 
corrective action) per the Accomplishment Instructions of Dornier 
Service Bulletin SB-328-71-125, Revision 3; and by doing all the 
actions per the Accomplishment Instructions of Dornier Service 
Bulletin SB-328-71-122, Revision 1; both dated May 10, 1999. Do any 
applicable corrective action before further flight per the 
applicable service bulletin.

    Note 2:
    The de-icing boots approved for installation on the modified 
engine inlet assembly are specified in paragraph 3., ``Material 
Information,'' of the Accomplishment Instructions of Dornier Service 
Bulletin SB-328-30-432, dated April 26, 2002.


    Note 3:
    Dornier Service Bulletin SB-328-71-122, Revision 1, dated May 
10, 1999, references Westland Aerospace Limited Service Bulletin SB-
WAL328-71-122, dated September 25, 1995, as an additional source of 
service information for modification of the air intake ducts; and 
Dornier Service Bulletin SB-328-71-125, Revision 3, dated May 10, 
1999, references SB-WAL328-71-125, Revision 1, dated September 25, 
1995, as an additional source of service information for 
installation of the cover plate of the bypass duct outlet.

Repetitive Inspections

    (g) Within 60 flight hours after accomplishment of paragraph (f) 
of this AD: Do a detailed inspection of the engine air inlet de-
icing boots to find discrepancies (including flat or soft spots in 
concave sections, defects on the de-icing boots, or improper 
sealing), per paragraph 2.B.1. of the Accomplishment Instructions of 
Dornier Service Bulletin SB-328-30-432, dated April 26, 2002. Do any 
applicable corrective action before further flight per the service 
bulletin. Repeat the inspection thereafter at intervals not to 
exceed 60 flight hours.
    (h) Within 400 flight hours after accomplishment of paragraph 
(f) of this AD: Do a debonding/delamination and leakage inspection 
of the engine air inlet de-icing boots by doing all the applicable 
actions per the Accomplishment Instructions of Dornier Service 
Bulletin SB-328-30-432, dated April 26, 2002. Do any applicable 
corrective action before further flight per the service bulletin. 
Repeat the inspection thereafter at intervals not to exceed 400 
flight hours.
    (i) Initiation of the repetitive inspections required by 
paragraphs (g) and (h) of this AD terminates the repetitive 
inspections required by paragraphs (b) and (c) of this AD.

No Reporting Required

    (j) Where Dornier Service Bulletin SB-328-30-432, dated April 
26, 2002; describes procedures for completing a reporting sheet with 
inspection results, this AD does not require that action.

Alternative Methods of Compliance

    (k)(1) In accordance with 14 CFR 39.19, the Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
is authorized to approve alternative methods of compliance for this 
AD.
    (2) Alternative methods of compliance, approved previously in 
accordance with AD 95-04-51, amendment 39-9179, are not considered 
to be approved as alternative methods of compliance with this AD.

    Note 4:
    The subject of this AD is addressed in German airworthiness 
directives 1995-156/3, dated July 1, 1999; and 2002-256, dated 
September 5, 2002.


    Issued in Renton, Washington, on March 26, 2004.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-7303 Filed 3-24-04; 8:45 am]
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