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Proposed Rule

Airworthiness Directives; Boeing Model 737-300, -400, -500, -600, -700, -700C, -800, and -900 Series Airplanes

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Supplemental notice of proposed rulemaking (NPRM); reopening of comment period.

SUMMARY:

The FAA is revising an earlier proposed airworthiness directive (AD) for certain Boeing Model 737-300, -400, -500, -600, -700, -700C, -800, and -900 series airplanes. The original NPRM would have required modifying the wiring for the master dim and test system. For certain airplanes, the original NPRM also proposed to require related concurrent actions as necessary. The original NPRM resulted from a report that the master dim and test system circuit does not have wiring separation of the test ground signal for redundant equipment in the flight compartment. This action revises the original NPRM by adding a new concurrent action for certain airplanes, extending the compliance time, and removing certain airplanes from concurrent requirements. We are proposing this supplemental NPRM to prevent a single fault failure in flight from simulating a test condition and showing test patterns instead of the selected radio frequencies on the communications panels, which could inhibit communication between the flightcrew and the control tower, affecting the continued safe flight of the airplane.

DATES:

We must receive comments on this supplemental NPRM by June 20, 2006.

ADDRESSES:

Use one of the following addresses to submit comments on this supplemental NPRM.

  • Docket Web site: Go to http//dms.dot.gov and follow the instructions for sending your comments electronically.
  • Government-wide rulemaking Web site: Go to http//www.regulations.gov and follow the instructions for sending your comments electronically.
  • Mail: Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, room PL-401, Washington, DC 20590.
  • Fax: (202) 493-2251.
  • Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207, for service information identified in this proposed AD.

Start Further Info

FOR FURTHER INFORMATION CONTACT:

Binh Tran, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 917-6485; fax (425) 917-6590.

End Further Info End Preamble Start Supplemental Information

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any relevant written data, views, or arguments regarding this supplemental NPRM. Send your comments to an address listed in the ADDRESSES section. Include the docket number “Docket No. FAA-2004-19245; Directorate Identifier 2004-NM-108-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this supplemental NPRM. We will consider all comments received by the closing date and may amend this supplemental NPRM in light of those comments.

We will post all comments submitted, without change, to http//dms.dot.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this supplemental NPRM. Using the search function of that Web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you may visit http//dms.dot.gov.

Examining the Docket

You may examine the AD docket on the Internet at http//dms.dot.gov, or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647-5227) is located on the plaza level in the Nassif Building at the DOT street address stated in ADDRESSES. Comments will be available in the AD docket shortly after the Docket Management System receives them. Start Printed Page 30347

Discussion

We proposed to amend 14 CFR part 39 with a notice of proposed rulemaking (NPRM) for an AD (the “original NPRM”) for certain Boeing Model 737-300, -400, -500, -600, -700, -700C, -800 and -900 series airplanes. The original NPRM was published in the Federal Register on October 5, 2004 (69 FR 59559). The original NPRM proposed to require modifying the wiring for the master dim and test system. For certain airplanes, the original NPRM also proposed to require related concurrent actions as necessary.

Relevant Service Information

We have reviewed Boeing Service Bulletin 737-33-1133, Revision 3, dated September 8, 2005. The service bulletin describes actions similar to those in Boeing Service Bulletin 737-33-1133, Revision 2, dated December 4, 2003, which was described in the original NPRM as the applicable source of service information for certain proposed actions on certain airplanes. Revision 3 also reduces the number of airplanes subject to certain actions specified in Boeing Service Bulletin 737-33-1121, Revision 1, dated December 19, 2002. The NPRM refers to 737-33-1121 as the applicable source of service information for certain concurrent actions.

Boeing Special Attention Service Bulletin 737-33-1132, Revision 2, dated September 8, 2005, describes actions similar to Boeing Special Attention Service Bulletin 737-33-1132, Revision 1, dated March 4, 2004, which was described in the original NPRM as the applicable source of service information for certain proposed actions on certain other airplanes. Revision 2 also adds a concurrent action for certain airplanes.

For certain airplanes, Service Bulletin 737-33-1132, Revision 2, recommends prior or concurrent accomplishment of Boeing Service Bulletin 737-23-1102, dated June 3, 1999. Service Bulletin 737-23-1102 describes procedures to replace the VHF and HF communications panels with radio control panels.

Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition.

Comments

We have considered the following comments on the original NPRM.

Supportive Comment

One commenter, Alaska Airlines, supports the original NPRM.

Request To Delay Release of AD Pending Release of Revised Service Bulletins

Boeing requests that the FAA delay issuing the AD until the release of Revision 3 of Boeing Service Bulletin 737-33-1133. The commenter states that implementing Service Bulletin 737-33-1133 at Revision 2, and implementing the associated concurrent service bulletin (Boeing Service Bulletin 737-33-1121, Revision 1, dated December 19, 2002), would require operators to perform unnecessary tasks. The commenter also points out that revising the service bulletin would help reduce the economic impact of the AD by removing the unnecessary tasks. We infer that the commenter wants the FAA to reference Revision 3 of the service bulletin.

We agree to reference Boeing Service Bulletin 737-33-1133, Revision 3, dated September 8, 2005, for the reasons stated by the commenter. We have determined that this delay would have no adverse effect on safety, and that reference to Revision 3 would assist operators in complying with this supplemental NPRM. We have revised paragraph (f) of this AD accordingly.

Requests From Operators To Delay Release of the AD

The Air Transport Association (ATA), on behalf of its member, Continental Airlines, requests that certain Boeing service bulletins be revised or withdrawn as referenced service bulletins. Continental states that there are multiple open issues (such as unnecessary steps for airplanes with certain different control panel configurations) and complications with those service bulletins. Continental further suggests that if the service bulletins are not revised, then the AD should be delayed until the open issues with some of the Boeing service bulletins are resolved.

We agree that certain service bulletins referenced in the NPRM need revisions. Since publication of the NPRM, some of the affected service bulletins have been revised to address open issues and complications. However, we do not agree to delay the issuance of this AD until all the affected service bulletins are revised. Compliance with some of the other affected and un-revised service bulletins may involve requesting alternative methods of compliance (AMOCs), since we have determined that it could affect safety if we wait for the remaining affected service bulletins to be revised. Boeing has also advised that it does not plan to revise a few of the remaining affected service bulletins. We have revised paragraphs (f), (g) and (h) of this supplemental NPRM to reference these revised service bulletins as applicable. Operators are welcome to apply for an AMOC as specified in paragraph (i) of this supplemental NPRM.

Requests To Extend Compliance Time To Modify Wiring

The ATA, on behalf of its members, American Airlines, United Airlines (UAL), and US Airways, requests extending the compliance time from 30 months to better match operators' heavy/base maintenance schedule. US Airways suggests a 48-month compliance time and states that the proposed 30-month compliance time doesn't match maintenance cycles. UAL also notes that the 30-month compliance time will create an increase in the time needed for C-check visits. American Airlines suggests re-wording the compliance time to “the next heavy overhaul visit” to prevent unnecessary financial hardship for the airlines.

We agree to extend the compliance time. We have considered other similar actions and have determined that extending the compliance time to 48 months will not adversely affect safety. We have revised paragraph (f) of this supplemental NPRM accordingly. We do not agree to use “the next heavy overhaul visit,” since it is an imprecise compliance time, and the definition of heavy overhaul visit can vary significantly between airplane operators.

Requests To Give Credit for Airplanes Equipped With Aircraft Communication and Reporting System (ACARS)

The ATA, on behalf of UAL, requests that we give credit for airplanes equipped with ACARS. UAL states that the NPRM does not give credit for those airplanes that are equipped with other means of ground communication. UAL explains that ACARS transmits data to an operator's dispatch group through the number 3 VHF system (VHF3), which is dedicated solely for ACARS usage. The frequency tuning for VHF3 is controlled by ACARS, not the VHF control panel. UAL concludes that ACARS provides an equivalent level of safety for the purposes of the NPRM since the flightcrew is still able to communicate with the ground, even if the fault occurs.

We partially agree with the commenters that ACARS provides some level of communication with the ground (usually the airplane operator's dispatch or ground support office) when the fault occurs. However, assuming the Start Printed Page 30348operator's dispatch office is able to establish a telephone line with the relevant air traffic control (ATC) tower or center, the delays in relaying information between the flightcrew and ATC via ACARS can be substantial. This fault also simulates a “test condition” that activates several flight annunciators, switches, and displays, so that the selected communication frequency cannot be determined from the displays. This increases the workload of the flightcrew and has an impact to the safety of the airplane during the approach and landing phase of flight. Therefore, the supplemental NPRM has not been revised to allow credit for airplanes equipped with ACARS.

Request To Revise Cost Estimate

The ATA, on behalf of UAL, requests that we revise the cost estimate of the modification in the NPRM. UAL states that Service Bulletin 737-33-1132 estimates the modification to take 21 work hours to complete, and the FAA estimates 14 work hours for the modification. UAL believes that the actual cost would be $1,740 per airplane whereas we estimate it at $910 per airplane.

We disagree to revise the estimate of the work hours since the cost estimate includes only the time necessary to perform the specific actions actually proposed by this supplementary NPRM. The service bulletin provides a work hour estimate that includes time needed to gain access to and close up the work area. Our estimates also typically do not include incidental costs such as planning time, access/close-up time, or other incidental or administrative actions. However, since we published the original NPRM, we have revised our cost estimate of a work hour from $65 to $80 to account for the increased cost of each work hour since we last revised that cost estimate. The estimates in Cost of Compliance have been revised accordingly.

Request To Revise Service Bulletins To Identify Airplanes With Enhanced Ground Proximity Warning System (EGPWS)

Continental Airlines requests that Boeing Service Bulletin 737-33-1132 be revised to identify airplanes modified by Boeing's EGPWS installation service bulletins and create an additional grouping for these EGPWS-modified airplanes. The commenter states that Service Bulletin 737-33-1132 has instructions to terminate a wire (number W149-045-22) to the navigation control panel. Continental adds that the wire has already been terminated at the MMR control panel on airplanes modified by the EGPWS service bulletins.

We agree that provisions need to be made for airplanes that have had EGPWS installed in accordance with the Boeing EGPWS service bulletins. Rather than revising Service Bulletin 737-33-1132 to address EGPWS modifications, Boeing has issued Service Bulletin 737-34-1924, dated October 17, 2005, to address wire changes and separation. Therefore Service Bulletin 737-33-1132 does not need to be revised. We have not changed the supplemental NPRM in this regard. However, if the commenter believes there is still potential for confusion or uncertainty, it is welcome to apply for an AMOC to use Service Bulletin 737-34-1924 in accordance with paragraph (i) of the supplemental NPRM.

Revise Service Bulletin To Remove Certain Requirements for Non-Integrated Audio Control Panels (ACPs)

Continental Airlines and Southwest Airlines request that the Boeing Service Bulletins 737-33-1133 and 737-33-1121 be revised to make installing provisional wiring for lamp test function an optional action for airplanes equipped with non-integrated ACPs. Southwest states that Boeing indicated that the wiring for the lamp test is only for fleet commonality for airplanes without integrated ACPs. Southwest believes that actions should not be mandated for the sake of fleet commonality.

We agree that the provisional wiring for the lamp test function should not be required for the non-integrated ACPs. Boeing has revised Service Bulletin 737-33-1133 so that the actions of Service Bulletin 737-33-1121 will not be required concurrent action on airplanes that do not have integrated ACPs. The supplemental NPRM refers to this revised service bulletin.

Request To Accommodate Airplanes With Certain Post-Delivery Wiring Changes

Southwest Airlines requests that the wiring installation listed within the Boeing service bulletins for automatic direction finder (ADF) control panels, Selective Calling on the radio communication system (SELCAL), and engine instrument system (EIS), be made optional for airplanes without ADF, SELCAL, and EIS installed. The airline states that it does not have SELCAL installed in its fleet, nor does it operate any airplanes with an EIS system, and is currently in the process of removing all ADF control panels from its fleet.

We agree that such actions should be optional for those airplanes without those systems installed. However, Boeing has decided not to revise the service bulletins (Boeing Service Bulletins 737-33-1132, 737-77-1022, and 737-77-1023 for non-EIS configurations and Boeing Service Bulletin 737-33-1133 for non-SELCAL configurations) to address airplanes with these post-delivery wiring modifications. It is not feasible to address each operator's configuration in this supplemental NPRM. Operators may submit a request for an AMOC in accordance with paragraph (i) of this supplemental NPRM.

Clarification of AMOC Paragraph

We have revised this supplemental NPRM to clarify the appropriate procedure for notifying the principal inspector before using any approved AMOC on any airplane to which the AMOC applies.

FAA's Determination and Proposed Requirements of the Supplemental NPRM

The changes discussed above expand the scope of the original NPRM; therefore, we have determined that it is necessary to reopen the comment period to provide additional opportunity for public comment on this supplemental NPRM.

Costs of Compliance

There are about 2,868 airplanes of the affected design in the worldwide fleet. This supplemental NPRM would affect about 1,181 airplanes of U.S. registry. The following table provides the estimated costs for U.S. operators to comply with this supplemental NPRM.

Estimated Costs

Boeing Service BulletinWork hoursAverage labor rate per hourPartsCost per airplane
737-33-1132, Revision 214$80Nominal$1,120
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737-33-1133, Revision 3380Nominal240

Estimated Concurrent Service Bulletin Costs

Boeing service bulletinWork hoursAverage labor rate per hourPartsCost per airplaneNumber of U.S.-registered airplanesFleet cost
737-26A1083, Revision 1185$80Between $30,000 and $36,400Between $44,800 and $51,2001Between $44,800 and $51,200.
737-33-1121, Revision 1Between 5 and 680Between $200 and $340Between $600 and $82083Between $49,800 and $68,060.
737-77-1022, Revision 17280No charge$5,7604$23,040.
737-77-1023, Revision 1Between 1 and 380NominalBetween $80 and $24026Between $2,080 and $6,240.
737-23-11027780$22,164$28,3240No fleet cost unless an affected airplane is imported and placed on U.S. register.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD 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.

For the reasons discussed above, I certify that the 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. 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.

We prepared a regulatory evaluation of the estimated costs to comply with this supplemental NPRM and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.

Start List of Subjects

List of Subjects in 14 CFR Part 39

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The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

Start Part

PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Start Authority

Authority: 49 U.S.C. 106(g), 40113, 44701.

End Authority
[Amended]

2. The Federal Aviation Administration (FAA) amends § 39.13 by adding the following new airworthiness directive (AD):

Boeing: Docket No. FAA-2004-19245; Directorate Identifier 2004-NM-108-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by June 20, 2006.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Boeing Model 737-300, -400, and -500 series airplanes identified in Boeing Special Attention Service Bulletin 737-33-1132, Revision 2, dated September 8, 2005; and Model 737-600, -700, -700C, -800, and -900 series airplanes identified in Boeing Service Bulletin 737-33-1133, Revision 3, dated September 8, 2005; certificated in any category.

Unsafe Condition

(d) This AD results from a report that the master dim and test system circuit does not have wiring separation of the test ground signal for redundant equipment in the flight compartment. We are issuing this AD to prevent a single fault failure in flight from simulating a test condition and showing test patterns instead of the selected radio frequencies on the communications panels, which could inhibit communication between the flightcrew and the control tower, affecting the continued safe flight of the airplane.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Modification

(f) Within 48 months after the effective date of this AD: Modify the wiring for the master dim test system in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 737-33-1132, Revision 2, dated September 8, 2005 (for Model 737-300, -400, and -500 series airplanes); and Boeing Service Bulletin 737-33-1133, Revision 3, dated September 8, Start Printed Page 303502005 (for Model 737-600, -700, -700C, -800, and -900 series airplanes); as applicable.

Actions Required To Be Accomplished Prior to or Concurrently With Paragraph (f) of This AD

(g) Prior to or concurrently with accomplishment of paragraph (f) of this AD, do the actions specified in Table 1 of this AD, as applicable.

Table 1.—Prior/Concurrent Actions

For—Accomplish all actions associated with—According to the Accomplishment Instructions of—
Group 57 airplanes identified in Boeing Special Attention Service Bulletin 737-33-1132, Revision 2, dated September 8, 2005Installing an engine instrument system (EIS) andBoeing Service Bulletin 737-77-1022, Revision 1, dated October 26, 1989.
Modifying the advisory system for the EISBoeing Service Bulletin 737-77-1023, Revision 1, dated November 9, 1989.
Group 37 and 46 airplanes identified in Boeing Service Bulletin 737-33-1133, Revision 3, dated September 8, 2005Installing wiring for the test system for the audio control panel lampBoeing Service Bulletin 737-33-1121, Revision 1, dated December 19, 2002.
Group 2 airplanes identified in Boeing Service Bulletin 737-33-1121, Revision 1, dated December 19, 2002Installing splice SP896Boeing Service Bulletin 737-26A1083, Revision 1, dated November 15, 2001.
Group 39 airplanes identified in Boeing Service Bulletin 737-33-1133, Revision 3, dated September 8, 2005Installing a smoke detection and fire extinguishing system in the cargo compartmentBoeing Service Bulletin 737-26A1083, Revision 1, dated November 15, 2001.
Group 59 airplanes identified in Boeing Special Attention Service Bulletin 737-33-1132, Revision 2, dated September 8, 2005Replacing the VHF and HF communications panels with radio control panelsBoeing Service Bulletin 737-23-1102, dated June 3, 1999.

Actions Accomplished per Previous Issue of Service Bulletins

(h) Actions accomplished before the effective date of this AD in accordance with the service bulletins identified in Table 2 of this AD are considered acceptable for compliance with the corresponding actions specified in this AD.

Table 2.—Previous Issues of Service Bulletins

Service BulletinRevision levelDate
Boeing Service Bulletin 737-33-1133OriginalDecember 19, 2002.
Boeing Service Bulletin 737-33-1133Revision 1April 17, 2003.
Boeing Service Bulletin 737-33-1133Revision 2December 4, 2003.
Boeing Special Attention Service Bulletin 737-33-1132OriginalMarch 20, 2003.
Boeing Special Attention Service Bulletin 737-33-1132Revision 1March 4, 2004.

Alternative Methods of Compliance (AMOCs)

(i)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

(2) Before using any AMOC approved in accordance with § 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.

Start Signature

Issued in Renton, Washington, on May 15, 2006.

Kevin M. Mullin,

Acting Manager, Transport Airplane Dierctorate, Aircrft Certification Service.

End Signature End Part End Supplemental Information

[FR Doc. E6-8120 Filed 5-25-06; 8:45 am]

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