AD 2002-03-05

[Federal Register Volume 67, Number 29 (Tuesday, February 12, 2002)]
[Rules and Regulations]
[Pages 6381-6385]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 02-3311]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-242-AD; Amendment 39-12646; AD 2002-03-05]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Model DC-8 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain McDonnell Douglas Model DC-8 series airplanes, 
that requires, among other things, repetitive leak tests of the 
lavatory drain systems and repair, if necessary; installation of a 
lever lock cap, vacuum breaker check valve, or flush/fill line ball 
valve on the flush/fill line; periodic seal changes; and replacement of 
``donut'' type waste drain valves installed in the waste drain system. 
This amendment is prompted by continuing reports of damage to engines, 
airframes, and property on the ground, caused by ``blue ice'' that 
forms from leaking lavatory drain systems on transport category 
airplanes and subsequently dislodges from the airplane fuselage. The 
actions specified by this AD are intended to prevent such damage 
associated with the problems of ``blue ice.''

DATES: Effective March 19, 2002.

ADDRESSES: This information may be examined at the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, Rules Docket, 
1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Los Angeles 
Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, 
California; or at the Office of the Federal Register, 800 North Capitol 
Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Samuel Lee, Aerospace Engineer, 
Airframe Branch, ANM-130L, FAA, Los Angeles Aircraft Certification 
Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; 
telephone (562) 627-5338; fax (562) 627-5210.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to certain McDonnell Douglas Model 
DC-8 series airplanes was published in the Federal Register on July 9, 
1998 (63 FR 37074). That action proposed to require among other things, 
repetitive leak tests of the lavatory drain systems and repair, if 
necessary; installation of a lever lock cap, vacuum breaker check 
valve, or flush/fill line ball valve on the flush/fill line; periodic 
seal changes; and replacement of ``donut'' type waste drain valves 
installed in the waste drain system.

Comments Received

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

Support for the Proposed Rule

    One commenter agrees with the proposal.

Request To Use a Leak Check Tool

    One commenter requests that the FAA revise paragraph (a) of the 
proposed rule to specify that it is not necessary to pressurize the 
aircraft to verify the integrity of service panel drain valves if the 
maintenance personnel perform a leak test. The commenter states that 
such a revision would be consistent with other ADs. The commenter also 
notes that such testing of the inner seal with air in a leak test is 
much more stringent than testing with a liquid, as it is obviously much 
easier for air to leak than the lavatory fluid. The commenter also 
requests that the FAA revise the duration of the leak test from five 
minutes to one minute when testing the inner seals of service panel 
valves with a leak check tool that applies a vacuum from the downstream 
side of the valve.
    The FAA does not agree that paragraph (a) of this AD should be 
revised for the reasons the commenter states. We note that the Shaw 
Aero vacuum test tool has been approved to allow testing without 
requiring fluid upstream of the valve. However, if specific procedures 
were provided for using a leak test too, the FAA would consider a 
request for an alternative method of compliance in accordance with 
paragraph (d) of this AD. Since the commenter did not submit data that 
would justify a shorter interval for the vacuum test tool, we have no 
basis to reduce the duration of the leak test. No change is necessary 
to the final rule in this regard.

Request To Revise the Interval for Changing the Valve Seals

    One commenter requests that the interval for changing the 
Pneudraulics valve seals specified in paragraph (a) of the proposed 
rule be reduced from every

[[Page 6382]]

6,000 flight hours to every 5,000 flight hours. The commenter states 
that the design limitations, and the potential for ice, hardened 
debris, and ``black tar'' build-up on the ball at the service panel 
seals are much more susceptible to damage. Additionally, the commenter 
notes that the location of the service panel (Pneudraulics valve) 
relative to the in-line ball valve makes those seals or mating surfaces 
more susceptible to damage by service and maintenance personnel.
    The FAA does not agree with the commenter's request. The 6,000-
flight hour interval for changing the Pneudraulics valve seals is based 
on extensive operating experience. Further, we have received no adverse 
reports on the Pneudraulics valve seals describing those problems that 
were indicated by the commenter. No change to the final rule is 
necessary in this regard.

Request To Extend the Leak Check Intervals for Certain Valves

    One commenter requests that the leak test interval for Shaw Aero 
valves listed in Table 1 of the proposed AD be extended from every 
1,000 flight hours to every 2,000 flight hours. The commenter argues 
that the in-service history of the Shaw Aero devices demonstrates a 
reliability factor that justifies such an extension.
    The FAA agrees with the commenter's request, and has previously 
provided a similar interval extension for those valves on other ``blue 
ice'' related ADs. We have revised Table 1 of the final rule to reflect 
extension of the leak check interval to every 2,000 flight hours for 
those valves. Since the valves specified in Table 1 are now approved 
for an interval of 2,000 flight hours, we have removed Table 1 from 
paragraph (a)(4) of the NPRM that specifies approval for an interval of 
1,000 flight hours, and have inserted Table 1 into paragraph (a)(3) of 
the final rule that specifies approval for valves with an interval of 
2,000 flight hours.

Request To Correct Certain Part Numbers (P/Ns)

    One commenter requests that certain P/Ns listed in Table 1 of the 
proposed AD be corrected. The FAA concurs and has revised Table 1 of 
the final rule.

Request To Revise Economic Estimate

    This same commenter requests that the FAA add the cost of 
performing a leak check with the vacuum pump test tool. The commenter 
states that operators should be made aware that the vacuum pump test 
tool is more economical than pressurizing the airplane to obtain the 
required 3-pounds-per-square-32inch (psi) differential pressure.
    The FAA does not agree that the estimated costs should be revised 
for the reasons the commenter states. As stated above, operators may 
request an alternative method of compliance for using the vacuum pump 
test tool by providing us with specific procedures for performing the 
leak test. Even though using the vacuum pump test tool may be less 
costly and may reduce the time required to perform the leak test, no 
dollar values were provided to us for comparison. No change is 
necessary to the final rule in this regard.

Conclusion

    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes previously 
described. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.

Cost Impact

    There are approximately 306 Model DC-8 series airplanes of the 
affected design in the worldwide fleet. The FAA estimates that 229 
airplanes of U.S. registry and 26 U.S. operators will be affected by 
this AD.
    The required waste drain system leak test and outer cap inspections 
will take approximately 6 work hours per airplane to accomplish, at an 
average labor rate of $60 per work hour. Based on these figures, the 
cost impact on U.S. operators of the waste drain system leak test and 
outer cap inspection is estimated to be $82,440, or $360 per airplane, 
per test/inspection.
    Certain airplanes (i.e., those that have ``donut'' type drain 
valves installed) may be required to be leak tested as many as 15 times 
each year. Certain other airplanes having other valve configurations 
will be required to be leak tested as few as 3 times each year. Based 
on these figures, the cost impact of this requirement is estimated to 
be between $1,080 and $5,400 per airplane, per year.
    With regard to replacement of ``donut'' type drain valves, the cost 
of a new valve is approximately $1,200. However, the number of leakage 
tests for an airplane that flies an average of 3,000 flight hours a 
year is reduced from 15 tests to 3 tests, which essentially pays for 
the cost of the replacement valve, so that no additional net cost is 
incurred because of this change.
    The FAA estimates that it will take approximately 1 work hour per 
airplane to accomplish a visual inspection of the service panel drain 
valve cap/door seal and seal mating surfaces, at an average labor rate 
of $60 per work hour. As with leak tests, certain airplanes will be 
required to be visually inspected as many as 15 times or as few as 3 
times each year. Based on these figures, the cost impact of the 
required repetitive visual inspections is estimated to be between $180 
and $900 per airplane, per year.
    The required installation of the flush/fill line cap will take 
approximately 1 work hour per cap to accomplish, at an average labor 
rate of $60 per work hour. The cost of required parts will be $275 per 
cap. There is an average of 2.5 caps per airplane. Based on these 
figures, the cost impact of these requirements on U.S. operators is 
estimated to be $171,178, or $748 per airplane.
    The seal replacements of the drain valves required by paragraph (a) 
of this AD will take approximately 2 work hours to accomplish, at an 
average labor cost of $60 per hour. The cost of required parts will be 
$200 per each seal change. Based on these figures, the cost impact on 
U.S. operators of these requirements is estimated to be $73,280, or 
$320 per airplane, per replacement.
    The number of required work hours, as indicated above, is presented 
as if the accomplishment of the actions required in this AD were to be 
conducted as ``stand alone'' actions. However, in actual practice, 
these actions could be accomplished coincidentally or in combination 
with normally scheduled airplane inspections and other maintenance 
program tasks. Therefore, the actual number of necessary ``additional'' 
work hours will be minimal in many instances. Additionally, any costs 
associated with special airplane scheduling should be minimal.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the requirements of this 
AD action, and that no operator would accomplish those actions in the 
future if this AD were not adopted.
    The FAA recognizes that the obligation to maintain aircraft in an 
airworthy condition is vital, but sometimes expensive. Because ADs 
require specific actions to address specific unsafe conditions, they 
appear to impose costs that would not otherwise be borne by operators. 
However, because of the general obligation of operators to maintain 
aircraft in an airworthy condition, this appearance is deceptive. 
Attributing those costs solely to the issuance of this AD is 
unrealistic because, in the interest

[[Page 6383]]

of maintaining safe aircraft, prudent operators would accomplish the 
required actions even if they were not required to do so by the AD.
    A full cost-benefit analysis has not been accomplished for this AD. 
As a matter of law, in order to be airworthy, an aircraft must conform 
to its type design and be in a condition for safe operation. The type 
design is approved only after the FAA makes a determination that it 
complies with all applicable airworthiness requirements. In adopting 
and maintaining those requirements, the FAA has already made the 
determination that they establish a level of safety that is cost-
beneficial. When the FAA, as in this AD, makes a finding of an unsafe 
condition, this means that the original cost-beneficial level of safety 
is no longer being achieved and that the required actions are necessary 
to restore that level of safety. Because this level of safety has 
already been determined to be cost-beneficial, a full cost-benefit 
analysis for this AD would be redundant and unnecessary.

Regulatory Impact

    The regulations adopted herein will 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 final rule does not have federalism 
implications under Executive Order 13132.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it may be obtained 
from 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.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 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:

2002-03-05  McDonnell Douglas: Amendment 39-12646. Docket 97-NM-242-
AD.

    Applicability: Model DC-8 series airplanes equipped with a 
lavatory drainage system; 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 previously 
accomplished.
    To prevent engine damage, airframe damage, and/or hazard to 
persons or property on the ground as a result of ``blue ice'' that 
has formed from leakage of the lavatory drain system or flush/fill 
system and dislodged from the airplane, accomplish the following:
    (a) Accomplish the applicable requirements of paragraphs (a)(1) 
through (a)(9) of this AD at the time specified in each paragraph. 
For the waste drain system of any lavatory that incorporates more 
than one type of valve, only one of the waste drain system leak test 
procedures (the one that applies to the equipment with the longest 
leak test interval) must be conducted at each service panel 
location. During the performance of the waste drain system valve 
leak tests specified in this AD, fluid shall completely cover the 
upstream end of the valve being tested. The direction of the 3-
pounds per square inch differential pressure (PSID) shall be applied 
in the same direction as occurs in flight; the other waste drain 
system valves shall be open, and the minimum time to maintain the 
differential pressure shall be 5 minutes. Any revision of the seal 
change intervals or leak test intervals must be approved by the 
Manager, Los Angeles Aircraft Certification Office (ACO), FAA, 
Transport Airplane Directorate.

    Note 2: Inclusion of a valve in this AD does not mean that the 
valve has been certified for installation in DC-8 series airplanes. 
Certification of the valve for installation in the airplane must be 
accomplished by means acceptable to the FAA, if the valve has not 
been previously certified.

    (1) Replace the valve seals with new valve seals in accordance 
with the applicable schedule specified in paragraphs (a)(1)(i), 
(a)(1)(ii), and (a)(1)(iii) of this AD.
    (i) For each lavatory drain system that has an in-line drain 
valve installed, Kaiser Electroprecision P/N series 2651-278 or 
2651-357: Replace the seals within 5,000 flight hours after the 
effective date of this AD, or within 48 months after the last 
documented seal change, whichever occurs later. Thereafter, replace 
the seals at intervals not to exceed 48 months.
    (ii) For each lavatory drain system that has a Pneudraulics part 
number series 9527 valve: Replace the seals within 5,000 flight 
hours after the effective date of this AD, or within 18 months after 
the last documented seal change, whichever occurs later. Thereafter, 
replace the seals at intervals not to exceed 18 months or 6,000 
flight hours, whichever occurs later.
    (iii) For each lavatory drain system that has any other type of 
drain valve: Replace the seals within 5,000 flight hours after the 
effective date of this AD, or within 18 months after the last 
documented seal change, whichever occurs later. Thereafter, replace 
the seals at intervals not to exceed 18 months.
    (2) For each lavatory drain system that has an in-line drain 
valve installed, Kaiser Electroprecision P/N series 2651-278: Within 
4,500 flight hours after the effective date of this AD, and 
thereafter at intervals not to exceed 4,500 flight hours, accomplish 
the procedures specified in paragraphs (a)(2)(i) and (a)(2)(ii) of 
this AD.
    (i) Conduct a leak test of the toilet tank dump valve (in-tank 
valve that is spring-loaded closed and operable by a T-handle at the 
service panel) and the in-line drain valve. The toilet tank dump 
valve leak test must be performed by filling the toilet tank with a 
minimum of 10 gallons of water/rinsing fluid and testing for leakage 
after a period of 5 minutes. Take precautions to avoid overfilling 
the tank and spilling fluid into the airplane. The in-line drain 
valve leak test must be performed with a minimum of 3 PSID applied 
across the valve.
    (ii) If a service panel valve or cap is installed, perform a 
visual inspection to detect wear or damage that may allow leakage of 
the service panel drain valve outer cap/door seal and the inner seal 
(if the valve has an inner door with a second positive seal), and 
the seal mating surfaces.

    Note 3: For the purposes of this AD, a general visual inspection 
is defined as: ``A visual examination of an interior or exterior 
area, installation, or assembly to detect obvious damage, failure, 
or irregularity. This level of inspection is made under normally 
available lighting conditions such as daylight, hangar lighting, 
flashlight, or drop-light, and may require removal or opening of 
access panels or doors. Stands, ladders, or platforms may be 
required to gain proximity to the area being checked.''

    (3) For each lavatory drain system that has any of the following 
service panel drain valves installed: Pneudraulics P/N series 9527, 
Kaiser Electroprecision P/N 2651-357, or the Shaw Aero P/N's listed 
in Table 1 of this paragraph: Within 2,000 flight hours

[[Page 6384]]

after the effective date of this AD, and thereafter at intervals not 
to exceed 2,000 flight hours, accomplish the procedures specified in 
paragraphs (a)(3)(i) and (a)(3)(ii) of this AD. Table 1 is as 
follows:

   Table 1.--Shaw Aero Valves Approved for 2,000 Flight Hour Leak Test
                                Interval
------------------------------------------------------------------------
                                           Serial numbers approved for
   Shaw waste drain valve part number     2,000-hour leak test interval
------------------------------------------------------------------------
A. 331 Series and 332 Series...........  All.
B. 10101000B-A-1.......................  201 and higher.
C. 10101000BA2.........................  0130 and higher.
D. Certain 10101000B valves............  Any of these ``B'' series
                                          valves that incorporate the
                                          improvements of Shaw Service
                                          Bulletin 10101000B-38-1, dated
                                          October 7, 1994, and are
                                          marked ``SBB38-1-58''.
E. 10101000C-A-1.......................  0277 and higher.
F. 10101000CN OR C-N...................  3649 and higher.
G. Certain 10101000C valves............  Any of these ``C'' series
                                          valves that incorporate the
                                          improvements of Shaw Service
                                          Bulletin 10101000C-38-2 dated
                                          October 7, 1994, and are
                                          marked ``SBC38-2-58''.
H. 10101000C-R.........................  191 and higher (747-400).
I. 10101000C-G.........................  Superseded by 10101000C-R (747-
                                          400).
------------------------------------------------------------------------

    (i) Conduct a leak test of the toilet tank dump valve and the 
service panel drain valve. The toilet tank dump valve leak test must 
be performed by filling the toilet tank with a minimum of 10 gallons 
of water/rinsing fluid and testing for leakage after a period of 5 
minutes. Take precautions to avoid overfilling the tank and spilling 
fluid into the airplane. The leak test of the service panel drain 
valve must be performed with a minimum of 3 PSID applied across the 
valve inner door/closure device.
    (ii) Perform a visual inspection of the outer cap/door and seal 
mating surface for wear or damage that may cause leakage.
    (4) For each lavatory drain system that has a service panel 
drain valve installed, Kaiser Electroprecision P/N series 0218-0032: 
Within 1,000 flight hours after the effective date of this AD, and 
thereafter at intervals not to exceed 1,000 flight hours, accomplish 
the procedures specified in paragraphs (a)(4)(i) and (a)(4)(ii) of 
this AD.
    (i) Conduct a leak test of the toilet tank dump valve and 
service panel drain valve. The toilet tank dump valve leak test must 
be performed by filling the toilet tank with a minimum of 10 gallons 
of water/rinsing fluid and testing for leakage after a period of 5 
minutes. Take precautions to avoid overfilling the tank and spilling 
fluid into the airplane. The service panel drain valve leak test 
must be performed with a minimum of 3 PSID applied across the valve 
inner door/closure device.
    (ii) Perform a visual inspection of the outer cap/door and seal 
mating surface for wear or damage that may cause leakage.
    (5) For each lavatory drain system that has a service panel 
drain valve installed, Kaiser Electroprecision P/N series 0218-0026; 
or Shaw Aero Devices P/N series 10101000B or 10101000C (except as 
specified in paragraph (a)(3) of this AD): Within 600 flight hours 
after the effective date of this AD, and thereafter at intervals not 
to exceed 600 flight hours, accomplish the procedures specified in 
paragraphs (a)(5)(i) and (a)(5)(ii) of this AD.
    (i) Conduct a leak test of the toilet tank dump valve and the 
service panel drain valve. The leak test of the toilet tank dump 
valve must be performed by filling the toilet tank with a minimum of 
10 gallons of water/rinsing fluid and testing for leakage after a 
period of 5 minutes. Take precautions to avoid overfilling the tank 
and spilling fluid into the airplane. The service panel drain valve 
leak test must be performed with a minimum of 3 PSID applied across 
the valve inner door/closure device.
    (ii) Perform a visual inspection of the outer cap/door and seal 
mating surface for wear or damage that may cause leakage.
    (6) For each lavatory drain system with a lavatory drain system 
valve that incorporates either ``donut'' plug, Kaiser 
Electroprecision P/Ns 4259-20 or 4259-31; Kaiser Roylyn/Kaiser 
Electroprecision cap/flange P/Ns 2651-194C, 2651-197C, 2651-216, 
2651-219, 2651-235, 2651-256, 2651-258, 2651-259, 2651-260, 2651-
275, 2651-282, 2651-286; Shaw Aero Devices assembly P/N 0008-100; or 
other FAA-approved equivalent parts; accomplish the requirements of 
paragraphs (a)(6)(i), (a)(6)(ii), and (a)(6)(iii) of this AD at the 
times specified in those paragraphs. For the purposes of this 
paragraph ((a)(6)), ``FAA-approved equivalent part'' means either a 
``donut'' plug which mates with the cap/flange P/Ns listed above, or 
a cap/flange which mates with the ``donut'' plug P/Ns listed above, 
such that the cap/flange and ``donut'' plug are used together as an 
assembled valve.
    (i) Within 200 flight hours after the effective date of this AD, 
and thereafter at intervals not to exceed 200 flight hours, conduct 
leak tests of the toilet tank dump valve and the service panel drain 
valve. The leak test of the toilet tank dump valve must be performed 
by filling the toilet tank with a minimum of 10 gallons of water/
rinsing fluid and testing for leakage after a period of 5 minutes. 
Take precautions to avoid overfilling the tank and spilling fluid 
into the airplane. The service panel drain valve leak test must be 
performed with a minimum 3 PSID applied across the valve.
    (ii) Perform a visual inspection of the outer door/cap and seal 
mating surface for wear or damage that may cause leakage. This 
inspection shall be accomplished in conjunction with the leak tests 
of paragraph (a)(6)(i) of this AD.
    (iii) Within 5,000 flight hours after the effective date of this 
AD, replace all the ``donut'' valves identified in paragraph (a)(6) 
of this AD with another type of FAA-approved valve. Following 
installation of the replacement valve, perform the appropriate leak 
tests and seal replacements at the intervals specified for that 
replacement valve, as applicable.
    (7) For each lavatory drain system not addressed in paragraphs 
(a)(2), (a)(3), (a)(4), (a)(5), and (a)(6) of this AD: Within 200 
flight hours after the effective date of this AD, and thereafter at 
intervals not to exceed 200 flight hours, accomplish the procedures 
specified in paragraphs (a)(7)(i) and (a)(7)(ii) of this AD.
    (i) Conduct a leak test of the toilet tank dump valve and the 
service panel drain valve. The toilet tank dump valve leak test must 
be performed by filling the toilet tank with a minimum of 10 gallons 
of water/rinsing fluid and testing for leakage after a period of 5 
minutes. Take precautions to avoid overfilling the tank and spilling 
fluid into the airplane. The leak test of the service panel drain 
valve must be performed with a minimum of 3 PSID applied across the 
valve inner door/closure device.
    (ii) Perform a visual inspection of the outer cap/door and seal 
mating surface for wear or damage that may cause leakage.
    (8) For flush/fill lines: Within 5,000 flight hours after the 
effective date of this AD, perform the requirements of paragraph 
(a)(8)(i) or (a)(8)(ii) of this AD, as applicable; and paragraph 
(a)(8)(iii) of this AD. Thereafter, repeat these requirements at 
intervals not to exceed 5,000 flight hours, or 48 months after the 
last documented seal change, whichever occurs later.
    (i) If a lever lock cap is installed on the flush/fill line of 
the subject lavatory, replace the seals on the toilet tank anti-
siphon (check) valve and the flush/fill line cap. Perform a leak 
test of the toilet tank anti-siphon (check) valve with a minimum of 
3 PSID across the valve, in accordance with the applicable portions 
of paragraph (a)(8)(ii)(A) of this AD.
    (ii) If a vacuum breaker check valve, Monogram P/N series 3765-
190, or Shaw Aero Devices P/N series 301-0009-01 is

[[Page 6385]]

installed on the subject lavatory, replace the seals/O-rings in the 
valve. Perform a leak test of the vacuum breaker check valve and 
verify proper operation of the vent line vacuum breaker, in 
accordance with paragraphs (a)(8)(ii)(A) and (a)(8)(ii)(B) of this 
AD.
    (A) Leak test the toilet tank anti-siphon (check) valve or the 
vacuum breaker check valve by filling the toilet tank with water/
rinsing fluid to a level such that the bowl is approximately half 
full (at least 2 inches above the flapper in the bowl). Apply 3 PSID 
across the valve in the same direction as occurs in flight. The vent 
line vacuum breaker on vacuum breaker check valves must be pinched 
closed or plugged for this leak test. If there is a cap/valve at the 
flush/fill line port, the cap/valve must be removed/open during the 
test. Check for leakage at the flush/fill line port for a period of 
5 minutes.
    (B) Verify proper operation of the vent line vacuum breaker by 
filling the tank and checking at the fill line port for back 
drainage after disconnecting the fluid source from the flush/fill 
line port. If back drainage does not occur, replace the vent line 
vacuum breaker or repair the vacuum breaker check valve, in 
accordance with the component maintenance manual, to obtain proper 
back drainage. As an alternative to the test technique specified 
above, verify proper operation of the vent line vacuum breaker in 
accordance with the procedures of the applicable component 
maintenance manual.
    (iii) If a flush/fill ball valve, Kaiser Electroprecision P/N 
series 0062-0009, is installed on the flush/fill line of the subject 
lavatory, replace the seals in the flush/fill ball valve and the 
toilet tank anti-siphon valve. Perform a leak test of the toilet 
tank anti-siphon valve with a minimum of 3 PSID across the valve, in 
accordance with paragraph (a)(8)(ii)(A) of this AD.
    (9) If leakage is discovered during any leak test or inspection 
required by paragraph (a) of this AD, or if evidence of leakage is 
found at any other time, accomplish the requirements of paragraph 
(a)(9)(i), (a)(9)(ii), or (a)(9)(iii) of this AD, as applicable.
    (i) If a leak is discovered, prior to further flight, repair the 
leak. Prior to further flight after repair, perform the appropriate 
leak test as specified in paragraph (a) of this AD, as applicable. 
Additionally, prior to returning the airplane to service, clean the 
surfaces adjacent to where the leakage occurred to clear them of any 
horizontal fluid residue streaks; such cleaning must be to the 
extent that any future appearance of a horizontal fluid residue 
streak will be taken to mean that the system is leaking again.

    Note 4: For purposes of this AD, ``leakage'' is defined as any 
visible leakage, if observed during a leak test. At any other time 
(than during a leak test), ``leakage'' is defined as the presence of 
ice in the service panel, or horizontal fluid residue streaks/ice 
trails originating at the service panel. The fluid residue is 
usually, but not necessarily, blue in color.

    (ii) If any worn or damaged seal is found, or if any damaged 
seal mating surface is found, prior to further flight, repair or 
replace it in accordance with the valve manufacturer's maintenance 
manual.
    (iii) In lieu of performing the requirements of paragraph 
(a)(9)(i) or (a)(9)(ii) of this AD: Prior to further flight, drain 
the affected lavatory system and placard the lavatory inoperative 
until repairs can be accomplished.
    (b) For all airplanes: Unless accomplished previously, within 
5,000 flight hours after the effective date of this AD, perform the 
actions specified in either paragraph (b)(1), (b)(2), or (b)(3) of 
this AD:
    (1) Install an FAA-approved lever lock cap on the flush/fill 
lines for all lavatories. Or
    (2) Install a vacuum break, Monogram P/N series 3765-190, or 
Shaw Aero Devices P/N series 301-0009-01, in the flush/fill lines 
for all lavatories. Or
    (3) Install a flush/fill ball valve, Kaiser Electroprecision P/N 
series 0062-0009, on the flush/fill lines for all lavatories.
    (c) For any affected airplane acquired after the effective date 
of this AD: Before any operator places into service any airplane 
subject to the requirements of this AD, a schedule for the 
accomplishment of the leak tests required by this AD shall be 
established in accordance with either paragraph (c)(1) or (c)(2) of 
this AD, as applicable. After each leak test has been performed 
once, each subsequent leak test must be performed in accordance with 
the new operator's schedule, in accordance with paragraph (a) of 
this AD.
    (1) For airplanes that have been maintained previously in 
accordance with this AD, the first leak test to be performed by the 
new operator must be accomplished in accordance with the previous 
operator's schedule or with the new operator's schedule, whichever 
results in the earlier accomplishment date for that leak test.
    (2) For airplanes that have not been previously maintained in 
accordance with this AD, the first leak test to be performed by the 
new operator must be accomplished prior to further flight, or in 
accordance with a schedule approved by the FAA Principal Maintenance 
Inspector (PMI), but within a period not to exceed 200 flight hours.

Alternative 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, Los Angeles ACO. Operators shall 
submit their requests through an appropriate FAA PMI, who may add 
comments and then send it to the Manager, Los Angeles ACO.

    Note 5: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Los Angeles ACO.

Special Flight Permits

    (e) 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.

Effective Date

    (f) This amendment becomes effective on March 19, 2002.

    Issued in Renton, Washington, on February 5, 2002.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 02-3311 Filed 2-11-02; 8:45 am]
BILLING CODE 4910-13-U