E8-12717. Airworthiness Directives; Boeing Model 777 Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

We are adopting a new airworthiness directive (AD) for certain Boeing Model 777 airplanes. This AD requires an inspection to determine the manufacturer and manufacture date of the oxygen masks in the center and outboard passenger service units, crew rests, and lavatory and flight attendant oxygen boxes, as applicable. This AD also requires related investigative/corrective actions if necessary. This AD results from a report that several passenger masks with broken in-line flow indicators were found following a mask deployment. We are issuing this AD to prevent the in-line flow indicators of the passenger oxygen masks from fracturing and separating, which could inhibit oxygen flow to the masks and consequently result in exposure of the passengers and cabin attendants to hypoxia following a depressurization event.

DATES:

This AD is effective July 16, 2008.

The Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD as of July 16, 2008.

ADDRESSES:

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

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 AD, the regulatory evaluation, any comments received, and other information. The address for the Docket Office (telephone [phone]) is the Document Management Facility, U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT:

Robert Hettman, Aerospace Engineer, Cabin Safety and Environmental Systems Branch, ANM-150S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an airworthiness directive (AD) that would apply to certain Boeing Model 777 airplanes. That NPRM was published in the Federal Register on January 10, 2008 (73 FR 1844). That NPRM proposed to require an inspection to determine the manufacturer and manufacture date of the oxygen masks in the center and outboard passenger service units (PSUs), crew rests, and lavatory and flight attendant oxygen boxes, as applicable. The NPRM also proposed to require related investigative/corrective actions if necessary.

Comments

We gave the public the opportunity to participate in developing this AD. We considered the comments received from the two commenters.

Request To Revise the Relevant Service Information Section

Boeing requests that we revise the Relevant Service Information section of the NPRM to include a general visual inspection of the flow indicator to determine whether the letter “W” appears on the right side of the identification (ID) label. Boeing states that this inspection should be included in the NPRM, since the presence of the letter “W” on the ID label indicates that the corrective actions have already been accomplished.

We agree to clarify the related investigative and corrective actions required by this AD. If the ID label on the oxygen mask shows that the mask was manufactured by B/E Aerospace between January 1, 2002 and March 1, 2006, then the related investigative action must be done. The related investigative action includes doing a general visual inspection of the flow indicator to determine the color of the flow direction mark and the word “flow” on the flow indicator, and to determine whether the letter “W” appears on the right side of the ID label. If the flow direction mark and the word “flow” on the flow indicator of the oxygen mask are not green and the letter “W” is not shown on the right side of the ID label, then the corrective action must be done. The corrective action includes replacing the oxygen mask with one that was not manufactured by B/E Aerospace between January 1, 2002, and March 1, 2006, or with a modified oxygen mask having an improved flow indicator. We have revised paragraph (f) of this AD accordingly. (Boeing Special Attention Service Bulletin 777-35-0019, dated March 9, 2006, refers to B/E Aerospace Service Bulletin 174080-35-01, dated February 6, 2006; and Revision 1, dated May 1, 2006; as additional sources of service information for modifying the oxygen mask assembly by replacing the flow indicator with an improved flow indicator.) The intent of this AD is to accomplish all of the applicable actions specified in the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-35-0019. Since the Relevant Service Information section is not retained in an AD, we have not changed this AD in this regard.

Request To Revise the Discussion Section

Boeing requests that we add a statement to the Discussion section of the NPRM clarifying that only masks manufactured by B/E Aerospace between January 1, 2002 and March 1, 2006 would require corrective action. Boeing states that no further action is required for oxygen masks manufactured outside those dates or manufactured by other suppliers. Boeing also states that not including all of the contents of Boeing Special Attention Service Bulletin 777-35-0019 in this AD, and not clarifying the intent of the AD, will generate many requests for clarification from operators.

We have clarified the requirements of this AD in our response to the previous comment. No additional change to this AD is necessary in this regard, since the Discussion section of the NPRM is not retained in this final rule.

Request To Delete Certain Requirements or Add a Terminating Action

British Airways states that it does not agree with the proposed requirement to replace a discrepant oxygen mask with one having an improved flow indicator because only the oxygen masks identified in Boeing Special Attention Service Bulletin 777-35-0019 are potentially defective. The commenter also states that it has inspected some of its airplanes and replaced all discrepant masks with new masks that do not fall within the rejection criteria. The commenter believes that it should not have to re-inspect the oxygen mask assemblies for the presence of an improved flow indicator after this AD is issued. The commenter, therefore, requests that we revise this AD in either one of the following ways:

• Delete the phrase from paragraph (f) of this AD that states “* * * except where the service bulletin specifies installing a new oxygen mask, replace the oxygen mask with a new or modified oxygen mask having an improved flow indicator.”
• Add a statement to this AD specifying that inspections done in accordance with Boeing Special Attention Service Bulletin 777-35-0019 before issuance of this AD comply with the intent of this AD and do not need to be repeated.

We agree that inspections done in accordance with Boeing Special Attention Service Bulletin 777-35-0019 before the effective date of this AD do not need to be accomplished again. However, no change is necessary in this regard, since a similar statement is contained already in paragraph (e) of this AD. Further, as stated previously, we have clarified the phrase regarding replacement of the oxygen mask in paragraph (f) of this AD. The intent of that phrase is to provide the option of replacing a discrepant oxygen mask with one that was not manufactured by B/E Aerospace between January 1, 2002, and March 1, 2006, or with a modified oxygen mask having an improved flow indicator in accordance with B/E Aerospace Service Bulletin 174080-35-01.

Conclusion

We reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting the AD with the change described previously. We also determined that this change will not increase the economic burden on any operator or increase the scope of the AD.

Costs of Compliance

There are about 433 airplanes of the affected design in the worldwide fleet. This AD affects about 123 airplanes of U.S. registry. The required actions take about 70 work hours per airplane, with an average of 480 oxygen masks per airplane, at an average labor rate of $80 per work hour. Based on these figures, the estimated cost of the AD for U.S. operators is $688,800, or $5,600 per airplane.

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

This AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify that this AD:

(1) Is not a “significant regulatory action” under Executive Order 12866,

(2) Is not a “significant rule” under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), and

(3) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

You can find our regulatory evaluation and the estimated costs of compliance in the AD Docket.

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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 AD:

2008-12-05 Boeing: Amendment 39-15548. Docket No. FAA-2007-0393; Directorate Identifier 2007-NM-183-AD.

Effective Date

(a) This airworthiness directive (AD) is effective July 16, 2008.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Boeing Model 777-200, -200LR, -300, and -300ER series airplanes, certificated in any category; as identified in Boeing Special Attention Service Bulletin 777-35-0019, dated March 9, 2006.

Unsafe Condition

(d) This AD results from a report that several passenger masks with broken in-line flow indicators were found following a mask deployment. We are issuing this AD to prevent the in-line flow indicators of the passenger oxygen masks from fracturing and separating, which could inhibit oxygen flow to the masks and consequently result in exposure of the passengers and cabin attendants to hypoxia following a depressurization event.

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.

Inspection and Related Investigative/Corrective Actions if Necessary

(f) Within 60 months after the effective date of this AD, do a general visual inspection to determine the manufacturer and manufacture date of the oxygen masks in the center and outboard passenger service units, crew rests, and lavatory and flight attendant oxygen boxes, as applicable, and do the applicable related investigative and corrective actions, by accomplishing all of the applicable actions specified in the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-35-0019, dated March 9, 2006; except where the service bulletin specifies installing a new oxygen mask, replace the oxygen mask with one that was not manufactured by B/E Aerospace between January 1, 2002, and March 1, 2006, or with a modified oxygen mask having an improved flow indicator. The related investigative and corrective actions must be done before further flight.

Note 1:

The Boeing service bulletin refers to B/E Aerospace Service Bulletin 174080-35-01, dated February 6, 2006; and Revision 1, dated May 1, 2006; as additional sources of service information for modifying the oxygen mask assembly by replacing the flow indicator with an improved flow indicator.

Alternative Methods of Compliance (AMOCs)

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

(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.

Material Incorporated by Reference

(h) You must use Boeing Special Attention Service Bulletin 777-35-0019, dated March 9, 2006, to do the actions required by this AD, unless the AD specifies otherwise.

(1) The Director of the Federal Register approved the incorporation by reference of this service information under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) For service information identified in this AD, contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.

(3) You may review copies of the service information incorporated by reference at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/​federal_​register/​code_​of_​federal_​regulations/​ibr_​locations.html.

Issued in Renton, Washington, on May 29, 2008.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.