05-16751. Airworthiness Directives; Boeing Model 747SP, 747SR, 747-100, -100B, -100B SUD, -200B, -200C, -200F, and -300 Series Airplanes

AGENCY:

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

ACTION:

Supplemental notice of proposed rulemaking; reopening of comment period.

SUMMARY:

This document revises an earlier proposed airworthiness directive (AD), applicable to all Boeing Model 747SP, 747SR, 747-100, -100B, -100B SUD, -200B, -200C, -200F, and -300 series airplanes, that would have required modification of the escape slide/raft pack assembly and cable release sliders. This new action revises the proposed rule by incorporating new service information, which clarifies the airplanes on which certain actions must be done, and by adding a new requirement for certain airplanes. The actions specified by this new proposed AD are intended to prevent improper deployment of the escape slide/raft or blockage of the passenger/crew doors in the event of an emergency evacuation, which could result in injury to passengers or crewmembers. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by September 19, 2005.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-213-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 [phone]. Comments may also be sent via the Internet using the following address: [e-mail]. Comments sent via fax or the Internet must contain “Docket No. 2001-NM-213-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 or 2000 or ASCII text.

The service information referenced in the proposed rule may be obtained from Boeing Commercial Airplanes, 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:

Keith Ladderud, Aerospace Engineer, Cabin Safety and Environmental Systems Branch, ANM-150S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this action may be changed in light of the comments received.

Submit comments using the following format:

• Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
• For each issue, state what specific change to the proposed AD is being requested.
• Include justification (e.g., reasons or data) for each request.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2001-NM-213-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. 2001-NM-213-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 all Boeing Model 747SP, 747SR, 747-100, -100B, -100B SUD, -200B, -200C, -200F, and -300 series airplanes, was published as a notice of proposed rulemaking (NPRM) (hereafter referred to as the “original NPRM”) in the Federal Register on September 10, 2003 (68 FR 53309). That NPRM would have required modification of the escape slide/raft pack assembly and cable release sliders. The original NPRM was prompted by improper escape slide/raft deployment and passenger/crew door blockage during slide deployment tests. That condition, if not corrected, could result in injury to passengers or crewmembers.

Comments

Due consideration has been given to the comments received in response to the original NPRM.

Request To Change Preamble/Add Revised Service Information

One commenter asks that Boeing Special Attention Service Bulletin 747-25-3274, Revision 2, dated August 26, 2004, be added to the first paragraph of the “Explanation of Relevant Service Information” section of the original NPRM. Revision 1 of the service bulletin was referenced in the original NPRM as the source of service information for modifying the slide/raft pack assembly. The commenter also asks that the following be added to that paragraph: “Note: Revision 2 will revise work instructions to move two airplane effectivities to a different group to reflect conversion from passenger configuration to special freighter configuration and will add a note that no work needs to be done at Door 3 left-hand and right-hand if Boeing Service Bulletin 747-25-2666, Revision 2, dated April 24, 2003, has previously been incorporated.”

The commenter asks that the term “pulley guard bracket” be changed to “cable guard bracket” in that same section and in the paragraph following “modification” of the original NPRM. The commenter provides no reason for these changes.

The commenter also asks that Boeing Special Attention Service Bulletin 747-25-3307, Revision 1, dated February 12, 2004, be added to the second paragraph of the “Explanation of Relevant Service Information” section of the original NPRM. The original issue of the service bulletin was referenced in the original NPRM as the source of service information for modifying the cable release sliders. The commenter also asks that the following be added to that paragraph: “Note: Revision 1 will add airplanes to service bulletin effectivities, combine Groups 2 and 3, and revise work instructions and Figure 2 to provide airlines with an alternate, easier modification.”

The commenter asks that the phrase “of the escape slide/raft pack assembly” be changed to “of the floor-mounted upper deck slide pack assembly.” The commenter provides no reason for these changes.

We acknowledge and agree with the commenter's remarks on the preamble of the original NPRM as these descriptions provide clarification; however, the “Explanation of Relevant Service Information” section is not restated in this supplemental NPRM. We have changed the term “pulley guard bracket” to “cable guard bracket” in paragraph (a)(2) of the supplemental NPRM, which is the only paragraph where the term is used. We have also changed the phrase “of the escape slide/raft pack assembly” to “of the floor-mounted upper deck slide pack assembly” in paragraph (b) of the supplemental NPRM.

Since issuance of the original NPRM, Boeing has issued, and we have reviewed, Boeing Special Attention Service Bulletin 747-25-3274, Revision 2, dated August 26, 2004; and Revision 3, dated December 16, 2004. Revision 2 contains the changes described previously by the commenter. Revision 2 also clarifies the airplanes on which certain actions must be done. Revision 3 is essentially the same as Revision 2, but the work hours and parts cost for the modification are reduced and Revision 3 provides further clarification of certain actions. Revision 3 specifies that no more work is necessary on airplanes changed as shown in Revision 2, except that certain cable assemblies must be replaced with new cable assemblies for airplanes on which Boeing Service Bulletin 747-25-2666, Revision 2, dated April 24, 2003; and Goodrich Service Bulletin 25-092, Revision 3, dated December 8, 1986 (superseded by Goodrich Service Bulletin 25-238, Revision 1, dated January 31, 2003); have been incorporated at Door 3 of the emergency exit. Service Bulletin 747-25-2666 describes procedures for installation of a one-piece ramp/slide at Door 3 of the emergency exit. Service Bulletins 25-092 and 25-238 describe procedures for modification of the escape slide raft assembly. We have added the new requirement specified in Service Bulletin 25-238 to paragraph (a)(2) of the supplemental NPRM.

In addition, as specified in Revision 3 of Service Bulletin 747-25-3274, no further action is required if corrective actions were performed in accordance with previous revisions, except as specified in paragraph 1.D., “Description”, of the service bulletin. That paragraph, in part, specifies that no more work is necessary on airplanes changed per Revision 1 of the service bulletin, except airplanes RD103 or RD104 that have incorporated Service Bulletin 747-25-2258 and have stored gas upper deck slides that should be modified by the instructions for Group 1 and Group 13 airplanes, as specified in Revision 3 of Service Bulletin 747-25-3274. Therefore, we have added Revision 3 of the service bulletin for accomplishing the modification specified in paragraph (a) of this supplemental NPRM, except as specified in paragraph 1.D. of the service bulletin.

We have also reviewed Boeing Special Attention Service Bulletin 747-25-3307, Revision 1, dated February 12, 2004; and Revision 2, dated July 8, 2004. Revision 1 contains the changes described previously. Revision 2 is essentially the same as Revision 1, and specifies that no more work is necessary on airplanes changed as shown in Revision 1. We have referenced Revision 2 of the service bulletin as the appropriate source of service information for accomplishing the modification required by paragraph (b) of this supplemental NPRM.

Request To Change Parts Installation Paragraph

One commenter, the airplane manufacturer, asks that paragraph (c) of the original NPRM be changed. The commenter states that, as written, paragraph (c) would not allow installation of certain parts on any airplane after the effective date of the AD. The commenter adds that it finds the requirements in this paragraph excessively restrictive because those requirements would not allow slides to be moved from one airplane to another, or installation of an overhauled slide during the next 36 months if an old part number cable is installed. The commenter states that, since the original NPRM affects slide/raft pack assemblies rather than airplanes, installing old cables after the effective date of the AD should be restricted to include the slide/raft pack assemblies only. The commenter suggests that paragraph (c) be changed as follows: “As of the effective date of this AD, no one may install, on any slide/raft pack assembly, a pin cable assembly with a part number listed.”

In light of the rationale provided by the commenter, we agree with the remark that the proposed requirements of paragraph (c) are too restrictive. Operators must comply with the requirements of this AD by the compliance time specified in paragraph (a) of the supplemental NPRM. If an operator must install an escape slide, it is their responsibility to ensure that all affected parts of that slide conform to the requirements of this supplemental NPRM by the compliance deadline. Accordingly, paragraph (c) of the proposed rule has not been included in this supplemental NPRM. (Operators should note, however, that once an airplane has been modified according to this AD, the airplane cannot be modified in any way that negates accomplishment of the actions in this AD—i.e., an escape slide with a modified cable assembly cannot be replaced with an escape slide with an unmodified cable assembly.)

Request To Remove Requirement for Prior or Concurrent Modification of Cable Release Sliders

The same commenter states that it does not agree that modification/replacement of the cable release sliders on the floor-mounted upper deck escape slide (as specified in paragraph (b) of the original NPRM) warrants an AD. Boeing Special Attention Service Bulletin 747-25-3307, Revision 2, dated July 8, 2004, is referenced as the appropriate source of service information for the concurrent modification required by paragraph (b). The commenter notes that although deployment forces can be higher than normal if the modification/replacement is not accomplished, the commenter is not aware of any non-deployment due to this condition.

We partially agree with the commenter. We agree that certain concurrent actions specified in Boeing Special Attention Service Bulletin 747-25-3307, Revision 2, are not necessary. We have determined that the concurrent modification specified in Figure 1 of the service bulletin is not required; however, the concurrent modification of the outboard cover panel, as specified in Figure 2 of the service bulletin, must be accomplished on Groups 2, 5, 6, 7, 8, 11, 12, 13, 14, and 15 airplanes. We have changed paragraph (b) of this supplemental NPRM accordingly.

Request To Change Applicability

One commenter asks that the applicability specified in the original NPRM be changed to specify a component (appliance), rather than airplanes, and suggests that the AD apply only to airplanes with floor-mounted upper deck slide pack assemblies having the part numbers identified in the referenced service information. The commenter states that the applicability specified can be misleading and has the potential to cause compliance and record-keeping errors. The commenter adds that the original NPRM should not be applicable to airplanes because the actions are required for a removable component; the component can be removed, repaired, and/or overhauled separately from the airplane, moved to another airplane, or stored until installation. The commenter notes that it operates several Model 747-100 series airplanes that do not have the affected floor-mounted upper deck slide pack assemblies installed, although the airplanes are included in the applicability. In addition, the commenter states that it operates one Model 747SR series airplane that is equipped with an affected assembly, but is not included in the effectivity specified in the referenced service information.

We do not agree with the commenter. Our general policy, when an unsafe condition results from an appliance or other item that is, or could be, installed on multiple airplane models, is that the AD is issued so that it is applicable to all of those airplane models, rather than to the item. The applicability of the original NPRM states “all” and takes precedence over the service bulletin effectivity. By making the AD applicable to the airplane models on which the appliance or other item is installed, we ensure that operators of those airplanes will be notified directly of the unsafe condition and the action required to correct it. While we assume that an operator will know the models of airplanes that it operates, there is a potential that the operator will not know or be aware of specific items that are installed on its airplanes. Therefore, calling out the airplane model as the subject of the AD prevents “unknowing non-compliance” on the part of the operator.

Additionally, there have been reports of non-deployments of escape slides that were delivered by Boeing with the airplane, as well as those that were installed post-delivery by the supplemental type certification (STC) process. After reviewing the in-service incidents, we found that all of the escape slides installed per the STC used the packboards that were delivered with the airplane. We then determined that specifying the airplane model in the applicability of the NPRM instead of the escape slide itself ensures that all discrepant cable assemblies are replaced on all Model 747 escape slide packboards, regardless of which airplane the escape slide is installed on. Therefore, components on airplanes not affected would not be overlooked. We have made no change to the supplemental NPRM in this regard.

Another commenter states that in the applicability of the original NPRM, Model 747-400F series airplanes are missing. The commenter notes that the upper deck slides on Model 747-400F series airplanes are the same as the slides installed on Model 747-200 series airplanes.

Although no specific request was made, we infer that the commenter wants us to add Model 747-400F series airplanes to the applicability of the supplemental NPRM. Although the slides for Model 747-200 and 747-400F series airplanes are similar, they are not interchangeable. When the Model 747-400F series airplanes were built, the escape slides that were installed had newer cover release cables which changed the configuration; therefore, the actions specified in the supplemental NPRM are not required for Model 747-400F series airplanes. We have made no change to the supplemental NPRM in this regard.

FAA's Determination and Proposed Requirements of the Supplemental NPRM

Since a certain change, discussed above, expands the scope of the original NPRM, we have determined that it is necessary to reopen the comment period to provide additional opportunity for public comment on this supplemental NPRM.

Changes to 14 CFR Part 39/Effect on the Original NPRM

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 system. The regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance (AMOCs). These changes are reflected in this supplemental NPRM.

Cost Impact

There are approximately 592 airplanes of the affected design in the worldwide fleet. We estimate that 187 airplanes of U.S. registry would be affected by this proposed AD.

It would take approximately 2 work hours per escape slide to accomplish the new proposed modification of the escape slide/raft pack assembly, at an average labor rate of $65 per work hour. Required parts would cost between $8,354 and $30,688 per airplane. Based on these figures, the cost impact of the modification of the escape slide/raft pack assembly proposed by this AD on U.S. operators is estimated to be between $1,586,508 and $5,762,966, or between $8,484 and $30,818 per airplane.

Should an operator be required to accomplish the overhaul of the cable release sliders, it would take approximately 2 work hours to accomplish the proposed overhaul, at an average labor rate of $65 per work hour. Required parts cost would be negligible. Based on these figures, the cost impact of the overhaul of the cable release sliders proposed by this AD on U.S. operators is estimated to be $130 per escape slide and $260 per airplane.

Should an operator be required to accomplish the replacement of the cable release sliders, it would take approximately 1 work hour to accomplish the proposed replacement, at an average labor rate of $65 per work hour. Required parts would cost approximately $2,940 per escape slide. Based on these figures, the cost impact of the replacement of the cable release sliders proposed by this AD on U.S. operators is estimated to be $3,005 per escape slide or $6,010 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.

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 Impact

The regulations proposed herein would not have a substantial direct effect on the States, on the relationship between the national Government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, it is determined that this proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this proposed regulation (1) is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39—AIRWORTHINESS DIRECTIVES

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

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

§ 39.13

[Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

Boeing: Docket 2001-NM-213-AD.

Applicability: All Model 747SP, 747SR, 747-100, -100B, -100B SUD, -200B, -200C, -200F, and -300 series airplanes; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent improper deployment of the escape slide/raft or blockage of the passenger/crew doors in the event of an emergency evacuation, which could result in injury to passengers or crewmembers, accomplish the following:

Modification

(a) Within 36 months after the effective date of this AD: Accomplish the actions specified in paragraphs (a)(1) and (a)(2) of this AD, as applicable, in accordance with Boeing Special Attention Service Bulletin 747-25-3274, Revision 3, dated December 16, 2004. Previously accomplishing the modification in accordance with Boeing Special Attention Service Bulletin 747-25-3274, Revision 1, dated January 9, 2003; or Revision 2, dated August 26, 2004; is acceptable for compliance with paragraph (a)(1) of this AD, except as specified in paragraph 1.D, ‘Description’, of Revision 3 of the service bulletin.

(1) For airplanes on which the actions specified in Boeing Service Bulletin 747-25-2666, Revision 2, dated April 24, 2003; and Goodrich Service Bulletin 25-238, Revision 1, dated January 31, 2003, have been accomplished: Replace cable assemblies having part number (P/N) 69B55462-( ) with new cable assemblies having P/N 416U6004-1.

(2) For airplanes on which the modification required by paragraph (a)(1) of this AD has not been accomplished: Modify the escape slide/raft pack assembly (includes removing the slide packs, replacing the cover release pin cable assemblies with new assemblies, and removing the cable guard bracket, as applicable).

Concurrent Modification

(b) For Groups 2, 5, 6, 7, 8, 11, 12, 13, 14, and 15 airplanes: Prior to or concurrently with accomplishment of paragraph (a) of this AD, modify the outboard cover panel of the cable release sliders of the floor-mounted upper deck slide pack assembly, as specified in Figure 2 of Boeing Special Attention Service Bulletin 747-25-3307, Revision 2, dated July 8, 2004.

Alternative Methods of Compliance

(c) 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.

Issued in Renton, Washington, on August 12, 2005.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.