E7-10864. Airworthiness Directives; McDonnell Douglas Model 717-200 Airplanes

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 all McDonnell Douglas Model 717-200 airplanes. The original NPRM would have required inspecting the power conversion distribution unit (PCDU) to determine its part number, and modifying certain PCDUs. The original NPRM was prompted by reports of failed PCDUs, the loss of an electrical bus, and the presence of a strong electrical burning odor in the flight deck and forward cabin. This action revises the original NPRM by reidentifying the part number reference for the proposed corrective action. We are proposing this supplemental NPRM to prevent the loss of an electrical bus due to PCDU failure, resulting in the loss of all flight displays for an unacceptable time period, and consequent emergency landing.

DATES:

We must receive comments on this supplemental NPRM by July 2, 2007.

ADDRESSES:

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

• DOT 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: [phone].
• 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, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Long Beach Division, Dept. C1-L5A (D800-0024), for service information identified in this proposed AD.

FOR FURTHER INFORMATION CONTACT:

Thomas Phan, Aerospace Engineer, Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone [phone]; fax [phone].

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-2006-26043; Directorate Identifier 2005-NM-010-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 [phone]) 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.

Discussion

We proposed to amend 14 CFR part 39 with a notice of proposed rulemaking (NPRM) for an AD (the “original NPRM”) for all McDonnell Douglas Model 717-200 airplanes. The original NPRM was published in the Federal Register on October 12, 2006 (71 FR 60080). The original NPRM proposed to require inspecting the power conversion distribution unit (PCDU) to determine its part number, and modifying certain PCDUs.

Comments

We have considered the following comments on the original NPRM.

Request To Revise Part Number Reference

Boeing and AirTran Airways note that the original NPRM incorrectly identifies P/N 762904E as the part number needing the corrective actions, but P/N 762904E (and any part number above 762904E) is the final configuration after all corrective actions are taken.

Since we issued the original NPRM, we became aware of this error. We revised paragraphs (f)(1) and (f)(2) in this supplemental NPRM to correctly identify the affected part numbers.

Request To State Intent To Incorporate Service Information by Reference During NPRM Stage

The Modification and Replacement Parts Association (MARPA) requests that, during the NPRM stage of AD rulemaking, the FAA state its intent to incorporate by reference (IBR) any relevant service information. MARPA states that, without such a statement in the NPRM, it is unclear whether the relevant service information will be incorporated by reference in the final rule.

We do not concur with the commenter's request. When we refer to certain service information in a proposed AD, the public can assume we intend to IBR that service information, as required by the Office of the Federal Register. No change to this supplemental NPRM is necessary in regard to the commenter's request.

Request To IBR Service Information During NPRM

This same commenter requests that we IBR the service information during the NPRM phase of rulemaking to permit the public to review and comment on the entire proposed action. The commenter notes that IBR is intended to avoid the unnecessary publication of documents already available to affected individuals. But the commenter expresses concern that distribution may not reach certain individuals directly responsible for the AD's accomplishment, including specialty shops, which now perform the majority of aircraft maintenance, and owners that are financing or leasing institutions.

We disagree that documents should be incorporated by reference during the NPRM phase of rulemaking. The Office of the Federal Register (OFR) requires that documents that are necessary to accomplish the requirements of the AD be incorporated by reference during the final rule phase of rulemaking. The final rule will incorporate by reference the document necessary for the accomplishment of the actions required in the AD. Further, we point out that, while documents that are incorporated by reference do become public information, they do not lose their copyright protection. For that reason, we advise the public to contact the manufacturer to obtain copies of the referenced service information. No change to the supplemental NPRM is necessary in response to this comment.

Request To Post Service Information on DMS Before Final Rule

This same commenter further requests that we post the service bulletins on the Department of Transportation's Docket Management System (DMS) to make the service bulletins available to the public before we issue the final rule.

We are currently in the process of reviewing issues surrounding the posting of service bulletins on the DMS as part of an AD docket. Once we have thoroughly examined all aspects of this issue and have made a final determination, we will consider whether our current practice needs to be revised. No change to this supplemental NPRM is necessary in response to this comment.

Request To Clarify Affected Parts

MARPA notes that the original NPRM would encompass both the original equipment manufacturer (OEM) and parts manufacturer approval (PMA) editions of the parts. And, “[p]ursuant to FAR 45.15 parts approved under 21.303 will have the term ‘FAA-PMA' included as part of the part numbering scheme.” But to resolve doubt and confusion when such parts are encountered in the field, MARPA requests that we explain that some parts may be marked “FAA-PMA,” and that the action would apply irrespective of the differences in part marking.

The FAA recognizes the need for standardization of this issue and is currently in the process of reviewing issues that address the use of PMAs in ADs at the national level. However, the Transport Airplane Directorate considers that to delay this particular AD action would be inappropriate, since we have determined that an unsafe condition exists and that replacement of certain parts must be accomplished to ensure continued safety. Therefore, no change has been made to this supplemental NPRM regarding this issue.

Clarification of Unsafe Condition

We have clarified certain language in the Summary and paragraph (d) of this supplemental NPRM to more accurately describe the unsafe condition that prompted this action.

Clarification of Alternative Method of Compliance (AMOC) Paragraph

We have revised this action 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

Certain 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 137 airplanes of the affected design in the worldwide fleet and 108 U.S.-registered airplanes. The following table provides the estimated costs for U.S. operators to comply with this proposed AD. The total fleet cost could be as high as $417,312.

Estimated Costs for Primary Actions

Boeing Service Bulletin	Work hours	Labor rate per hour	Parts cost	Cost per airplane
Part number identification	1	$80	$0	$80
Modification (717-24A0028)	12	80	0	960

Estimated Costs for Concurrent Actions

Hamilton Sundstrand Service Bulletin	Work hours	Labor rate per hour	Parts cost	Cost per airplane
40EGS22P-24-3	6	$80	$154 per airplane	$634
40EGS22P-24-4	3	80	0	240
40EGS22P-24-6	3	80	0	240
40EGS22P-24-7	1 per PCDU	80	10 per PCDU, maximum 3 PCDUs per airplane	110 (maximum).
40EGS22P-24-8	10	80	0	800
40EGS22P-24-9	10	80	0	800

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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• 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 Federal Aviation Administration (FAA) amends § 39.13 by adding the following new airworthiness directive (AD):

McDonnell Douglas: Docket No. FAA-2006-26043; Directorate Identifier 2005-NM-010-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by July 2, 2007.

Affected ADs

(b) None.

Applicability

(c) This AD applies to all McDonnell Douglas Model 717-200 airplanes, certificated in any category.

Unsafe Condition

(d) This AD was prompted by reports of failed power conversion distribution units (PCDUs), the loss of an electrical bus, and the presence of a strong electrical burning odor in the flight deck and forward cabin. We are issuing this AD to prevent the loss of an electrical bus due to PCDU failure, resulting in the loss of all flight displays for an unacceptable time period, and consequent emergency landing.

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.

Identification of PCDU Part Number

(f) Within 20 months after the effective date of this AD, inspect the PCDU to determine its part number. A review of airplane maintenance records is acceptable in lieu of this inspection if the part number can be conclusively determined from that review.

(1) If the part number is below 762904E, do the actions specified in paragraphs (g) and (h) of this AD.

(2) If the part number is 762904E or higher, no further work is required by this AD.

Modification

(g) Within 20 months after the effective date of this AD, modify the PCDU in accordance with Boeing Alert Service Bulletin 717-24A0028, Revision 1, dated December 20, 2005. A modification done before the effective date of this AD in accordance with Boeing Alert Service Bulletin 717-24A0028, dated November 24, 2004, is acceptable for compliance with the requirements of this paragraph.

Note 1:

Boeing Alert Service Bulletin 717-24A0028 refers to Hamilton Sundstrand Service Bulletin 40EGS22P-24-10, Revision 1, dated May 11, 2005, as an additional source of service information for the modification.

Concurrent Requirements

(h) Before or concurrently with the modification required by paragraph (g) of this AD, do the applicable actions specified in Table 1 of this AD.

Table 1.—Concurrent Service Bulletins

Do the following—	In accordance with Hamilton Sundstrand Service Bulletin—
Rework the transformer rectifier unit assembly (TRU) Rework the W3 wiring harness assembly to install direct lead wires to the TRU. Add a ground wire to the TRU transformer. Add an insulated spacer to the PCDU top cover.	40EGS22P-24-3, dated June 30, 2000.
Install new PCDU 186 firmware	40EGS22P-24-4, Revision 1, dated January 2, 2002.
Install new PCDU 186 firmware	40EGS22P-24-6, dated July 25, 2002.
Modify the top cover of the PCDU	40EGS22P-24-7, dated September 3, 2003.
Modify printed wiring board (PWB) assemblies A4 and A5 Check and apply torque seal to fasteners on the TRU assembly and to PCDU internal fasteners, as applicable.	40EGS22P-24-8, dated September 4, 2003.
Modify the PWB assembly A4	40EGS22P-24-9, dated November 19, 2003.

Credit for Accomplishment of Earlier Service Bulletin

(i) Installation of new PCDU 186 firmware before the effective date of this AD in accordance with Hamilton Sundstrand Service Bulletin 40EGS22P-24-4, dated April 26, 2001, is acceptable for compliance with the corresponding requirements of paragraph (h) of this AD.

Alternative Methods of Compliance (AMOCs)

(j)(1) The Manager, Los Angeles 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) 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.

Issued in Renton, Washington, on May 25, 2007.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.