2012-21556. Airworthiness Directives; The Boeing Company Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

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

SUMMARY:

We are revising an earlier proposed airworthiness directive (AD) for certain The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes. That NPRM proposed to require checking the escape slide girt for serviceability, and replacement if necessary; modifying the cable routing provision; replacing the regulator padding; modifying the aspirator orientation; and modifying the valise. That NPRM also proposed to require, for certain airplanes, modifying or replacing the Vespel piston, modifying the pilot valve regulator, installing a new firing cable and safety pin, and modifying the slide valise. That NPRM was prompted by reports of escape slides failing to deploy from the forward and aft right-hand doors during scheduled maintenance slide deployments. This action revises that NPRM by adding airplanes to the applicability of that NPRM and specifying revised service information. We are proposing this supplemental NPRM to prevent failure of an escape slide to deploy, which could result in the slide being unusable during an emergency evacuation and increased likelihood of injury to passengers or crewmembers due to the difficulty in evacuating the airplane. Since these actions impose an additional burden over that proposed in the NPRM, we are reopening the comment period to allow the public the chance to comment on these proposed changes.

DATES:

We must receive comments on this supplemental NPRM by October 15, 2012.

ADDRESSES:

You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590.
• Hand Delivery: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Goodrich Corporation, Aircraft Interior Products, Attn: Technical Publications, 3414 South Fifth Street, Phoenix, Arizona 85040; phone: [phone]; Internet: http://www.goodrich.com/​TechPubs. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov;​; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (phone: [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Sarah Piccola, Aerospace Engineer, Cabin Safety & Environmental Systems Branch, ANM-150S, Seattle Aircraft Certification Office (ACO), FAA, 1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: [phone]; fax: [phone]; email: [e-mail].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2011-1222; Directorate Identifier 2010-NM-268-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those comments.

We will post all comments we receive, without change, to http://www.regulations.gov,, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

We issued an NPRM to amend 14 CFR part 39 to include an AD that would apply to The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes. That NPRM published in the Federal Register on November 8, 2011 (76 FR 69159). That NPRM proposed to require checking the escape slide girt for serviceability and replacement if necessary, modifying the cable routing provision, the aspirator orientation, the valise, and replacing the regulator padding. That NPRM also proposed to require, for certain airplanes, modifying or replacing the Vespel piston, modifying the pilot valve regulator, modifying the slide valise, and installing a new firing cable and safety pin.

Actions Since Previous NPRM (76 FR 69159, November 8, 2011) Was Issued

Since we issued the previous NPRM (76 FR 69159, November 8, 2011), new service information has been issued that provides clarifications and minor corrections, and adds data. Additionally, an error was discovered in the part numbers (P/Ns) specified in paragraph (c), “Applicability,” of that NPRM. The specification of “P/N 5A3307-1, -3, -5, or -301, S/N BNG0001 through BNG5707 inclusive,” is incorrect. The part number should have read “P/N 5A3307-1, -3, -5, or -301, S/N BNG0001 through BNG14499 inclusive.” We have changed the supplemental NPRM in this regard.

Comments

We gave the public the opportunity to comment on the previous NPRM (76 FR 69159, November 8, 2011). The following presents the comments received on the NPRM and the FAA's response to each comment.

Requests To Use Revised Service Information

Boeing, United Airlines (United), and Goodrich Corporation (Goodrich) requested that the previous NPRM (76 FR 69159, November 8, 2011) be changed to incorporate revised service information to ensure that operators are incorporating the most current revision of the service information.

We agree that current service information should be incorporated into this supplemental NPRM. Goodrich Service Bulletin 5A3307-25-389, Revision 2, dated May 4, 2012; and Goodrich Service Bulletin 5A3307-25-339, Revision 5, dated May 4, 2012; provide minor corrections, updated pricing, and additional data. The technical content of these documents has not been changed. We have changed paragraphs (g) and (h)(1) of the supplemental NPRM to refer to Goodrich Service Bulletin 5A3307-25-389, Revision 2, dated May 4, 2012; and Goodrich Service Bulletin 5A3307-25-339, Revision 5, dated May 4, 2012; as applicable. We have changed paragraph (i) of the supplemental NPRM to include credit for modifications of the escape slide done before the effective date of the AD using Goodrich Service Bulletin 5A3307-25-339, Revision 3, dated May 8, 2009; or Revision 4, dated October 1, 2011. Modification of the escape slide specified in Goodrich Service Bulletin 5A3307-25-389, Revision 2, dated May 4, 2012, consists of modifying the cable routing provision, replacing the regulator padding, modifying the aspirator orientation, and modifying the valise. Modification of the escape slide specified in Goodrich Service Bulletin 5A3307-25-339, Revision 5, dated May 4, 2012, consists of modifying the pilot valve regulator P/N 4A3865-2, -3, or -4, as applicable; installing a new firing cable and safety pin; and modifying the slide valise.

Requests To Change Applicability

Goodrich, Boeing, United, AirTran Airways (AirTran), and Southwest Airlines (Southwest) requested that we change or clarify the applicability of the pervious NPRM (76 FR 69159, November 8, 2011) to include slide P/N 5A3307-1, -3, -5, or -301, S/Ns BNG0001 through BNG14499 inclusive. Boeing stated that this change “will ensure that all applicable 5A3307 series evacuation slides have been identified for incorporation of the Goodrich Service Bulletin 5A3307-25-389 modifications.”

We agree that S/Ns BNG0001 through BNG14499 inclusive should be included in the applicability of this supplemental NPRM as explained previously. We have changed paragraph (c) of the supplemental NPRM to include P/N 5A3307-1, -3, -5, or -301, S/N BNG0001 through BNG14499 inclusive.

Requests To Remove Slide Part Numbers From the NPRM (76 FR 69159, November 8, 2011)

Goodrich, United, and Boeing requested that we remove slide P/N 5A3086-1, -3, or -301, S/Ns B3F001 through B3F611 inclusive; P/N 5A3088-1, -3, or -301, S/Ns B3A001 through B3A685 inclusive; from the NPRM (76 FR 69159, November 8, 2011). Goodrich stated that specification of slide P/N 5A3086-1, -3, or -301, S/Ns B3F001 through B3F611 inclusive; and P/N 5A3088-1, -3, or -301, S/Ns B3A001 through B3A685 inclusive; is inappropriate for the proposed AD, because the unsafe condition that the proposed AD addresses is not an issue for the P/Ns 5A3086 and 5A3088 series slides. Goodrich also stated that the design of the P/Ns 5A3086 and 5A3088 series slides precludes the type of event that has been experienced with the P/N 5A3307 series slides. Goodrich provided detailed information to support its request.

We agree. Including these additional parts is confusing and is not directly related to the unsafe condition addressed by this supplemental NPRM. We have changed paragraph (c) of the supplemental NPRM to remove slide P/N 5A3086-1, -3, or -301, S/Ns B3F001 through B3F611 inclusive; and P/N 5A3088-1, -3, or -301, S/Ns B3A001 through B3A685 inclusive; from the supplemental NPRM.

Request To Remove Girt Check

Goodrich requested that the girt check be removed from the previous NPRM (76 FR 69159, November 8, 2011). Goodrich stated that the girt condition was not a causative factor in the unsafe condition described in the previous NPRM. The girt condition check is not a configuration requirement of the slide modification, which addresses the slide nondeployment issue. Rather, the girt condition check is included in the Goodrich service information because it falls under the heading of good general maintenance practice. Goodrich stated that the girt check specified in the Goodrich service information was not a causative factor in the unsafe condition described by the previous NPRM and questions the need for it to be called out in the AD.

We agree. The girt condition check is not a configuration requirement of the slide modification, which addresses the slide non-deployment issue. We have removed the girt condition check from paragraph (g) of the supplemental NPRM.

Requests To Remove Parts Installation Restriction

United, American, WestJet, Southwest, Goodrich, and AirTran requested that we remove paragraph (j) of the NPRM (76 FR 69159, November 8, 2011), which prohibits installing certain parts on any airplane after the effective date of the AD. The commenters stated that this prohibition would prevent the use of affected spare slide assemblies (un-modified) during modification of the slide units of the previous NPRM, as well as the removal and reinstallation of the same affected unit on an airplane. The commenters asserted that this requirement could restrict an airline's ability to return an airplane to service due to a shortage of parts.

Boeing requested that we remove paragraphs (j)(1) and (j)(3) from the previous NPRM (76 FR 69159, November 8, 2011). The P/N 5A3086-1, -3, and -301 evacuation slides; and P/N 5A3088-1, -3, and -301 evacuation slides are not affected by Goodrich Service Bulletin 5A3307-25-389, Revision 1, dated October 1, 2011, which is the subject of the previous NPRM. Boeing stated that, once the evacuation slide has been modified as specified in Goodrich Service Bulletin 5A3307-25-389, Revision 1, dated October 1, 2011, into the new P/N 5A3307-7 configuration, the old regulator and regulator valve padding parts will have been replaced with new parts; therefore, just listing P/N 5A3307-1, -3, -5, and -301 evacuation slides would cover the old regulator and regulator valve padding parts.

We agree with removing the parts installation restriction, since this prohibition could make it difficult for operators to maintain their airplanes. After the effective date of the AD, if the slides are removed for any reason, this prohibition could lead to an airplane with slides having mixed part numbers. We have removed paragraph (j) from the supplemental NPRM, and redesiginated subsequent paragraphs accordingly.

Request To Remove Repeated Wording

United requested that we address the need for repeating accomplishment instructions within paragraphs (g) and (h) of the previous NPRM (76 FR 69159, November 8, 2011). United stated that this information is already contained within Goodrich Service Bulletins 5A3307-25-389, Revision 1, dated October 1, 2011; and 5A3307-25-339, Revision 4, dated October 1, 2011; respectively, and by repeating this information, the AD could contain dated information.

We agree that repeating the specifics of the accomplishment instructions in paragraphs (g) and (h) of the supplemental NPRM is unnecessary in this case. We have changed paragraphs (g) and (h) of the supplemental NPRM to require modifying the escape slide in accordance with the applicable service information. We have described the specifics of modifying the escape slide in paragraphs (g) and (h) of the supplemental NPRM in the previous response under comment “Request to Use Revised Service Information.” No further change is necessary in this regard.

Request To Remove Certain Part Numbers

United requested that we address repetitive slide part numbers in the previous NPRM (76 FR 69159, November 8, 2011), which have already been subjected to previous AD rulemaking. United stated that including slide part numbers that were subjected to previously issued rulemaking, such as AD 2008-24-08, Amendment 39-15748 (73 FR 72320, November 28, 2008), undermines the rulemaking process and forces operators to demonstrate compliance against certain part numbers for a second time.

We agree and have removed P/Ns 5A3307-1 and 5A3307-3, which were the subject of previous rulemaking (AD 2008-24-08, Amendment 39-15748 (73 FR 72320, November 28, 2008)), from this supplemental NPRM.

FAA's Determination

We are proposing this supplemental NPRM because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design. Certain changes described above expand the scope of the original NPRM. As a result, we have determined that it is necessary to reopen the comment period to provide additional opportunity for the public to comment on this supplemental NPRM.

Proposed Requirements of the Supplemental NPRM

This supplemental NPRM would require accomplishing the actions specified in the service information described previously.

Costs of Compliance

We estimate that this proposed AD affects 557 airplanes of U.S. registry.

We estimate the following costs to comply with this proposed AD:

Estimated Costs

Action	Labor cost	Parts cost	Cost per product	Cost on U.S. operators
Modify girt and valise, and replace padding	2 work-hours × $85 per hour = $170	$223	$393	$218,901.
Modify regulator valve, install cable and pin, and modify slide valise	1 work-hour × $85 per hour = $85	Between $1,749 and $1,836	Between $1,834 and $1,921	Between $1,021,538 and $1,069,997.
Modify Vespel piston	1 work-hour × $85 per hour = $85	$0	$85	$47,345.
Optional Vespel piston replacement	Up to 1 work-hour × $85 per hour = $85	Up to $612	Up to $697	Up to $388,229.

We estimate the following costs to do any necessary replacements that would be required based on the results of the check of the girt. We have no way of determining the number of aircraft that might need these replacements.

On-Condition Costs

Action	Labor cost	Parts cost	Cost per product
Girt replacement (Goodrich Service Bulletin 5A3307-25-389, Revision 2, dated May 4, 2012)	1 work-hour × $85 per hour = $85	$942	$1,027

According to the parts supplier, some of the costs of this proposed AD may be covered under warranty, thereby reducing the cost impact on affected individuals. We do not control warranty coverage for affected individuals. As a result, we have included all costs in our cost estimate.

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 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 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),

(3) Will not affect intrastate aviation in Alaska, and

(4) 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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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.

§ 39.13

[Amended]

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

The Boeing Company: Docket No. FAA-2011-1222; Directorate Identifier 2010-NM-268-AD.

(a) Comments Due Date

We must receive comments by October 15, 2012.

(b) Affected ADs

This AD affects AD 2008-24-08, Amendment 39-15748 (73 FR 72320, November 28, 2008).

(c) Applicability

This AD applies to The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes; certificated in any category; with Goodrich Corporation door escape slide part number (P/N) 5A3307-1, -3, -5, or -301, serial number (S/N) BNG0001 through BNG14499 inclusive.

(d) Subject

Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 25, Equipment/Furnishings.

(e) Unsafe Condition

This AD was prompted by reports of escape slides failing to deploy from the forward and aft right-hand doors during scheduled maintenance slide deployments. We are issuing this AD to prevent failure of an escape slide to deploy, which could result in the slide being unusable during an emergency evacuation and increased likelihood of injury to passengers or crewmembers due to the difficulty in evacuating the airplane.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done.

(g) Slide Modification

Within 36 months after the effective date of this AD: Modify the escape slide in accordance with the Accomplishment Instructions of Goodrich Service Bulletin 5A3307-25-389, Revision 2, dated May 4, 2012.

(h) Concurrent Requirements

(1) For slide P/N 5A3307-301: Prior to or concurrently with accomplishing the actions required by paragraph (g) of this AD, modify the escape slide in accordance with the Accomplishment Instructions of Goodrich Service Bulletin 5A3307-25-339, Revision 5, dated May 4, 2012.

(2) For slide P/N 5A3307-301 or 5A3307-5: Prior to or concurrently with accomplishing the actions required by paragraph (g) of this AD, modify the Vespel piston in the regulator valves, or replace the Vespel piston with a new or serviceable Vespel piston P/N 3A3566-2 or 3A3832-2, as applicable, in accordance with the Accomplishment Instructions of Goodrich Service Bulletin 25-349, Revision 1, dated January 11, 2010.

(i) Credit for Previous Actions

(1) This paragraph provides credit for the actions required by paragraph (h)(1) of this AD, if those actions were performed before the effective date of this AD using Goodrich Service Bulletin 5A3307-25-339, Revision 1, dated September 26, 2003; Revision 2, dated March 31, 2004; Revision 3, dated May 8, 2009; or Revision 4, dated October 1, 2011; which are not incorporated by reference in this AD.

(2) This paragraph provides credit for the modification or replacement of the Vespel piston in the regulator valves required by paragraph (h)(2) of this AD, if those actions were performed before the effective date of this AD using Goodrich Service Bulletin 25-349, dated September 15, 2004, which is not incorporated by reference in this AD.

(j) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in the Related Information section of this AD. Information may be emailed to: [e-mail].

(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.

(k) Related Information

(1) For more information about this AD, contact Sarah Piccola, Aerospace Engineer, Cabin Safety & Environmental Systems Branch, ANM-150S, Seattle Aircraft Certification Office (ACO), FAA, 1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: [phone]; fax: [phone]; email: [e-mail].

(2) For service information identified in this AD, contact Goodrich Corporation, Aircraft Interior Products, ATTN: Technical Publications, 3414 South Fifth Street, Phoenix, Arizona 85040; phone: [phone]; Internet: http://www.goodrich.com/​TechPubs. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, the FAA, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.

Issued in Renton, Washington, on August 24, 2012.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.