[Federal Register Volume 68, Number 120 (Monday, June 23, 2003)]
[Proposed Rules]
[Pages 37105-37108]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-15727]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2000-NM-422-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-100, -200, -200C, -
300, -400, and -500 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Supplemental notice of proposed rulemaking; reopening of
comment period.
-----------------------------------------------------------------------
SUMMARY: This document revises an earlier proposed airworthiness
directive (AD), applicable to certain Boeing Model 737-100, -200, -
200C, -300, -400, and -500 series airplanes, that would have required
replacing the existing pressure relief valve on the potable water tank
with a new, improved pressure relief valve, which is made of stainless
steel and is non-adjustable. For certain airplanes, that earlier
proposed AD also would have required modification of certain piping to
re-locate the pressure relief valve. For certain other airplanes, this
new action would revise the earlier proposed AD by correcting
procedures for performing the proposed replacement of the pressure
relief valve. The actions specified by this new proposed AD are
intended to prevent rupture of the potable water tank during flight of
the airplane, which could result in structural damage to the airplane
and inability to sustain flight loads. This action is intended to
address the identified unsafe condition.
DATES: Comments must be received by July 18, 2003.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 2000-NM-422-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. 2000-NM-422-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 for Windows or
ASCII text.
The service information referenced in the proposed rule may be
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle,
Washington 98124-2207. This information may be examined at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington.
FOR FURTHER INFORMATION CONTACT: Don Eiford, Aerospace Engineer, ANM-
130S, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056; telephone (425) 917-6465; fax (425) 917-
6590.
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
[[Page 37106]]
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:
[sbull] 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.
[sbull] For each issue, state what specific change to the proposed
AD is being requested.
[sbull] 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
submitted in response to this action must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 2000-NM-422-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. 2000-NM-422-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
A proposal to amend part 39 of the Federal Aviation Regulations (14
CFR part 39) to add an airworthiness directive (AD), applicable to
certain Boeing Model 737-100, -200, -200C, -300, -400, and -500 series
airplanes, was published as a notice of proposed rulemaking (NPRM) in
the Federal Register on March 18, 2002 (67 FR 11950). That NPRM would
have required replacing the existing pressure relief valve on the
potable water tank with a new, improved pressure relief valve, which is
made of stainless steel and is non-adjustable. For certain airplanes,
that NPRM also would have required modifying certain piping to replace
a check valve with a tee, removing the existing pressure relief valve,
and installing a plug where the existing pressure relief valve was
located. That NPRM was prompted by reports indicating that there have
been several occurrences of potable water tanks rupturing while the
airplane was in flight. That condition, if not corrected, could result
in structural damage to the airplane and inability to sustain flight
loads. The purpose of the proposed modification is to relocate the
pressure relief valve so it is subject to the same air pressure as the
potable water tank, and therefore will protect the tank from
overpressurization. Accomplishment of the complete modification per
Boeing Service Bulletin 737-38-1029 would reinstall the existing
pressure relief valve in the tee installed per that service bulletin.
However, this supplemental NPRM would require installation of a new,
improved relief valve in the tee installed per Boeing Service Bulletin
737-38-1029 instead of reinstalling the existing pressure relief valve.
Issuance of a New Service Bulletin Revision
Since the issuance of the earlier NPRM, the FAA has reviewed and
approved Boeing Service Bulletin 737-38A1047, Revision 2, dated July
18, 2002. Revision 1 of that service bulletin, dated September 27,
2001, was referenced in the earlier NPRM as the appropriate service
information for removing the existing pressure relief valve from the
potable water tank, and replacing the valve with a new pressure relief
valve. Revision 2 of that service bulletin was issued to more closely
align certain airplane effectivity groups with the correct figures in
the Accomplishment Instructions. Revision 2 of that service bulletin
describes the procedures in a new Figure 9 for airplanes specified as
``Group 9,'' and also describes procedures in Figure 5 for airplanes
specified as ``Group 10.'' Revision 2 of that service bulletin states
that no more work is necessary if the actions described in the initial
issuance or Revision 1 of that service bulletin were accomplished.
Therefore, we have specified that accomplishment of the actions in this
supplemental NPRM be done per Revision 2 of Boeing Service Bulletin
737-38A1047.
Comments Received on the Earlier NPRM
Due consideration has been given to the comments received in
response to the earlier NPRM.
Request To Prohibit Reinstallation of Certain Parts
One commenter notes that Boeing Service Bulletin 737-38-1047,
Revision 1, dated September 27, 2001, is specified as the appropriate
service information in the earlier NPRM for removing pressure relief
valves having part number (P/N) 520A-6DB-50 or P/N D524TP6D60 and
replacing the valves with new pressure relief valves. The commenter
suggests that the FAA clarify that, after the effective date of the AD,
installation of pressure relief valves having P/N 520A-6DB-50 or P/N
D524TP6D60 is prohibited. The commenter states that such clarification
would prevent any unintended ``demodification'' of the airplane.
The FAA agrees with the commenter and has added a new paragraph (g)
of this supplemental NPRM to specifically prohibit installation of
those certain pressure relief valves.
Request To Clarify Leak Test Procedure
One commenter notes that the earlier NPRM would require certain
airplanes to be modified per Boeing Service Bulletin 737-38-1029,
Revision 1, dated August 19, 1993, followed by replacement of the
pressure relief valve per Boeing Service Bulletin 737-38A1047, Revision
1, dated September 27, 2001. However, the commenter points out that
each of the service bulletins describes a different leak check
procedure. The commenter requests that the earlier NPRM specify that
either leak check procedure is acceptable or state that neither leak
check procedure is mandated.
The FAA acknowledges that the two service bulletins describe two
different leak test (check) procedures. We have determined that the
leak test described in Boeing Service Bulletin 737-38A1047 is the
appropriate procedure. Therefore, we have specified in paragraph
(a)(1)(ii) of this supplemental NPRM that the leak test procedure
specified in Boeing Service Bulletin 737-38-1029 is not required to be
performed.
Request To Clarify Note 2 of the NPRM
One commenter, the manufacturer, states that Note 2 of the earlier
NPRM could be interpreted to be an acceptable alternative to the entire
content of paragraph (a)(1) of the NPRM, including the instructions in
paragraph (a)(1) of the earlier NPRM to perform the requirements of
paragraph (a)(2) of the NPRM. (Note 2 of the earlier NPRM specifies
that modification of the potable water pressurization system done in
accordance with Boeing Service Bulletin 737-38-1029, dated June 6,
[[Page 37107]]
1991, is acceptable for compliance with the requirements of paragraph
(a)(1) of the earlier NPRM.) The commenter notes that if the
modification described in the June 6, 1991, revision of the service
bulletin was installed, the existing pressure relief valve would still
be installed in the system. Although Note 2 of the earlier NPRM states
that performance of Boeing Service Bulletin 737-38-1029 is acceptable
for compliance with paragraph (a)(1), it does not specifically require
that the new, improved pressure relief valve be installed. The
commenter suggests that Note 2 of the NPRM be clarified.
The FAA concurs that clarification is needed to ensure that the
existing pressure relief valves are replaced with new, improved valves
for those airplanes identified in the effectivity section of Boeing
Service Bulletin 737-38-1029. (For reasons other than those discussed
in this response (see explanation under the heading below labeled
``Editorial Changes''), we have incorporated the intent of the
previously designated Notes 2, 3, and 4 of the NPRM into paragraphs
(a), (d), and (f), respectively, of this supplemental NPRM.)
This supplemental NPRM revises paragraph (a)(1) of the earlier NPRM
to specify that paragraph (a)(1) must be accomplished in accordance
with Boeing Service Bulletin 737-38-1029, dated June 6, 1991, or
Revision 1, dated August 19, 1993. Including Boeing Service Bulletin
737-38-1029, dated June 6, 1991, in paragraph (a)(1) of this
supplemental NPRM makes it unnecessary to provide the ``credit''
wording specified in Note 2 of the earlier NPRM. The supplemental NPRM
further revises paragraph (a)(2) of the earlier NPRM (replacing the
valve with a new pressure relief valve having part number P/N RV05-362)
to specify that paragraph (a)(2) must be accomplished in accordance
with Boeing Service Bulletin 737-38A1047, Revision 2, dated July 18,
2002.
Request To Limit the Applicability
One commenter requests that the applicability section of the NPRM
be revised to include the words, ``except those airplanes that have the
potable water systems removed or deactivated.'' The commenter states
that it operates two cargo airplanes that have had the potable water
systems deactivated. The commenter explains that the servicing port has
a cap installed and the potable water tank fill and transfer lines have
been disconnected and plugged. Also, the water tank is vented to
prevent it from pressurizing during flight.
The FAA does not agree that the applicability should be revised.
The FAA has determined that this supplemental NPRM is applicable to
certain Model 737-100, -200, -200C, -300, -400, and ``500 series
airplanes. We consider that, while there is currently no potable water
system on the commenter's fleet, a potable water system could be
installed at a later date. Therefore, no change to the supplemental
NPRM is necessary in this regard. For those airplanes that currently
may not have a potable water system installed, the operators may
request approval of an alternative method of compliance as provided in
paragraph (h) of this AD.
Editorial Changes
Because the language in Notes 2, 3, and 4 of the earlier NPRM is
regulatory in nature, the intent of those notes has been incorporated
into paragraphs (a), (d), and (f) of this supplemental NPRM.
Other Changes
On July 10, 2002, the FAA issued a new version of 14 CFR part 39
(67 FR 47997, July 22, 2002), which governs the FAA's airworthiness
directives systems. The regulation now includes material that relates
to altered products, special flight permits, and alternative methods of
compliance (AMOC). Because we have now included this material in part
39, only the office authorized to approve AMOCs is identified in each
individual AD. Therefore, paragraphs (c) and (d) and Note 1 of the
original NPRM have been removed from this supplemental NPRM.
Conclusion
Since these changes expand the scope of the earlier proposed rule,
the FAA has determined that it is necessary to reopen the comment
period to provide additional opportunity for public comment.
Cost Impact
There are approximately 2,049 Model 737-100, -200, -200C, -300, -
400, and -500 series airplanes of the affected design in the worldwide
fleet. The FAA estimates that 1,144 airplanes of U.S. registry would be
affected by this proposed AD.
The FAA estimates that, of the 1,144 airplanes of U.S. registry, 2
would be affected by the proposed modification of piping to re-locate
the pressure relief valve, that it would take approximately 6 work
hours per airplane to accomplish the proposed modification, and that
the average labor rate is $60 per work hour. Based on these figures,
the cost impact of the proposed modification of piping on U.S.
operators is estimated to be $720, or $360 per airplane.
The FAA estimates that all of the 1,144 airplanes of U.S. registry
would be affected by the proposed replacement of the pressure relief
valve, that it would take approximately 2 work hours per airplane to
accomplish the replacement, and that the average labor rate is $60 per
work hour. Required parts would cost approximately $300 per airplane.
Based on these figures, the cost impact of the replacement of the
pressure relief valve on U.S. operators is estimated to be $480,480, or
$420 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. 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
[[Page 37108]]
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:
Boeing: Docket 2000-NM-422-AD.
Applicability: Model 737-100, -200, -200C, -300, -400, and -500
series airplanes; line numbers 1 through 2696 inclusive;
certificated in any category.
Compliance: Required as indicated, unless accomplished
previously.
To prevent rupture of the potable water tank during flight of
the airplane, which could result in structural damage to the
airplane and inability to sustain flight loads, accomplish the
following:
Modification and Replacement
(a) For those airplanes listed in the effectivity section of
Boeing Service Bulletin 737-38-1029, Revision 1, dated August 19,
1993, on which the modification of the potable water pressurization
system specified in the service bulletin has not been accomplished:
Within 18 months after the effective date of this AD, except as
specified in paragraph (d) of this AD, perform the requirements of
paragraphs (a)(1) and (a)(2) of this AD.
(1) Except as specified in paragraphs (a)(1)(i) and (a)(1)(ii)
of this AD, modify the potable water pressurization system; in
accordance with Boeing Service Bulletin 737-38-1029, dated June 6,
1991, or Revision 1, dated August 19, 1993.
(i) Do not reinstall the existing pressure relief valve having
part number (P/N) 520A-6DB-50.
(ii) Do not perform the leak test procedures specified in the
service bulletin.
(2) Install a new pressure relief valve having part number P/N
RV05-362, in accordance with Boeing Service Bulletin 737-38A1047,
Revision 2, dated July 18, 2002.
(b) For those airplanes listed in the effectivity section of
Boeing Service Bulletin 737-38-1029, dated June 6, 1991, or Revision
1, dated August 19, 1993, on which the modification of the potable
water pressurization system specified in that service bulletin has
been accomplished: Within 18 months after the effective date of this
AD, remove the existing pressure relief valve from the potable water
tank, and replace the valve with a new pressure relief valve having
part number P/N RV05-362; in accordance with Boeing Service Bulletin
737-38A1047, Revision 2, dated July 18, 2002.
(c) For all other airplanes having line numbers 1 through 2523
inclusive: Within 18 months after the effective date of this AD
unless previously accomplished, remove the existing pressure relief
valve from the potable water tank, and replace the valve with a new
pressure relief valve having part number P/N RV05-362, in accordance
with Boeing Service Bulletin 737-38A1047, Revision 2, dated July 18,
2002.
Acceptable Compliance With Certain Paragraphs
(d) With the exception of airplanes specified as ``Group 9'' or
``Group 10'' in Boeing Service Bulletin 737-38A1047, Revision 2,
dated July 18, 2002, having line numbers 1 through 2523 inclusive:
Installation of a new pressure relief valve having P/N RV05-362, in
accordance with Boeing Service Bulletin 737-38A1047, dated November
9, 2000, or Revision 1, dated September 27, 2001, is acceptable for
compliance with paragraph (a)(2), (b), or (c) of this AD.
Replacement of Pressure Relief Valve
(e) For airplanes having line numbers 2524 through 2696
inclusive, with the exception of those airplanes specified in
paragraph (f) of this AD: Within 18 months after the effective date
of this AD, remove the existing pressure relief valve from the
potable water tank and replace the valve with a new pressure relief
valve having P/N RV05-362, in accordance with Boeing Service
Bulletin 737-38A1038, Revision 2, dated September 25, 1997.
Acceptable Compliance With Paragraph (e) of this AD
(f) For those airplanes having line numbers 2524 through 2696
inclusive and having air compressors installed in the potable water
tank pressurization system: Within 18 months after the effective
date of this AD, remove the existing pressure relief valve from the
potable water tank and replace the valve with a new pressure relief
valve having P/N RV05-362, in accordance with Boeing Service
Bulletin 737-38A1038, dated December 1, 1994; or Revision 1, dated
February 2, 1995.
Part Installation
(g) As of the effective date of this AD, no person may install a
pressure relief valve having P/N 520A-6DB-50, 520A6DB60, or P/N
D524TP6D60 on any airplane.
Alternative Methods of Compliance
(h) In accordance with 14 CFR 39.19, the Manager, Seattle
Aircraft Certification Office, FAA, is authorized to approve
alternative methods of compliance for this AD.
Issued in Renton, Washington, on June 17, 2003.
Michael J. Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 03-15727 Filed 6-20-03; 8:45 am]
BILLING CODE 4910-13-P