05-17402. Airworthiness Directives; McDonnell Douglas Model DC-9-10, DC-9-20, DC-9-30, DC-9-40, and DC-9-50 Series Airplanes; McDonnell Douglas Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) Airplanes; McDonnell Douglas ...

AGENCY:

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

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for certain McDonnell Douglas transport category airplanes. This proposed AD would require an inspection to determine the part number of the upper and lower stop pad support fittings of all the lower cargo doors, repetitive inspections of all early configuration stop pad support fittings, and corrective action if necessary. This proposed AD would also provide an optional terminating action for the repetitive inspections. This proposed AD is prompted by a report of cracks found in the area of the upper and lower stop pad support fittings of the cargo door pan on numerous airplanes. We are proposing this AD to prevent cracks in the cargo door pan, which could result in the inability to fully pressurize an airplane and possible rapid decompression of the airplane.

DATES:

We must receive comments on this proposed AD by October 17, 2005.

ADDRESSES:

Use one of the following addresses to submit comments on this proposed AD.

• 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.
• By 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.

For service information identified in this proposed AD, contact Boeing Commercial Airplanes, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data and Service Management, Dept. C1-L5A (D800-0024).

You can examine the contents of this AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., room PL-401, on the plaza level of the Nassif Building, Washington, DC. This docket number is FAA-2005-22254; the directorate identifier for this docket is 2005-NM-001-AD.

FOR FURTHER INFORMATION CONTACT:

Maureen Moreland, Aerospace Engineer, Airframe Branch, ANM-120L, 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 proposed AD. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2005-22254; Directorate Identifier 2005-NM-001-AD” in the subject line of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments submitted by the closing date and may amend the proposed AD in light of those comments.

We will post all comments we receive, 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 proposed AD. 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 can review DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you can visit http://dms.dot.gov.

Examining the Docket

You can 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 of the Nassif Building at the DOT street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after the DMS receives them.

Discussion

We have received a report indicating that an operator found cracks in the area of the upper and lower stop pad support fittings of the cargo door pan, on numerous McDonnell Douglas Model DC-9 airplanes. These airplanes had accumulated between 23,944 and 32,735 total flight hours (and between 23,626 and 30,598 total flight cycles, respectively). We have also been notified that these early configuration stop pad support fittings could have been installed on the lower cargo doors of Model MD-90-30 and Model 717-200 airplanes during airplane production. Early configuration stop pad support fittings could fail and cause cracks along the top and bottom of the cargo door pan. This condition, if not corrected, could result in the inability to fully pressurize an airplane and possible rapid decompression of the airplane.

Other Related Rulemaking

On May 8, 1996, we issued AD 96-10-11, amendment 39-9618 (61 FR 24675, May 16, 1996), applicable to certain McDonnell Douglas Model DC-9 and DC-9-80 series airplanes, Model MD-88 airplanes, and C-9 (military) series airplanes. Paragraph (b) of that AD requires initial and repetitive inspections to detect cracks in several areas in accordance with the DC-9/MD-80 Aging Aircraft Service Action Requirements Document, McDonnell Douglas Report No. MDC K1572, Revision B, dated January 15, 1993 (hereafter referred to as SARD, Revision B). SARD, Revision B, refers to several McDonnell Douglas service bulletins as additional sources of service information for accomplishing those various inspections.

In particular, SARD, Revision B, refers to McDonnell Douglas DC-9 Service Bulletin 52-89 (for Model DC-9-10, DC-9-20, DC-9-30, DC-9-40, and DC-9-50 series airplanes), Revision 5, dated February 26, 1991, for inspecting the forward and aft lower cargo doors to detect cracks. Those inspections are identical to the repetitive inspections that would be required by this proposed AD, in accordance with Boeing Service Bulletin DC9-52-189, Revision 01, dated March 20, 2003. Therefore, accomplishing the repetitive inspections, which would be required by this proposed AD, terminates the repetitive inspections of the forward and aft lower cargo doors required by paragraph (b) of AD 96-10-11.

McDonnell Douglas DC-9 Service Bulletin 52-89, Revision 5; and Revision 6, dated January 11, 1993; also describe procedures for doing a preventative modification. The preventative modification includes installing doublers, fittings, webs, angles, clips, and other structural parts in the forward and aft lower cargo doors. If early configuration stop pad support fittings are installed on a lower cargo door, this proposed AD would reinstate inspections of the lower cargo doors at the same inspection interval, regardless of whether the preventative modification of McDonnell Douglas DC-9 Service Bulletin DC9-52-89, Revision 5, or Revision 6, has been previously accomplished.

Relevant Service Information

We have reviewed the following Boeing Service Bulletins:

• DC9-52-189, Revision 01, excluding Appendix A, dated March 20, 2003, for McDonnell Douglas Model DC-9-10, DC-9-20, DC-9-30, DC-9-40, DC-9-50 series airplanes; Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) airplanes; and Model MD-88 airplanes;
• MD90-52-014, dated December 14, 2004, for McDonnell Douglas Model MD-90-30 airplanes; and
• 717-52-0007, dated December 14, 2004, for McDonnell Douglas Model 717-200 airplanes.

The service bulletins describe the following procedures:

• For certain airplanes, inspecting to determine the part number of the upper and lower stop pad support fittings of lower cargo doors.
• If any early configuration stop pad support fitting is installed on a lower cargo door, doing either repetitive visual or repetitive eddy current inspections for cracks in the lower cargo door.

For Boeing Service Bulletins MD90-52-014 and 717-52-0007, the corrective action includes contacting the manufacturer for repair instructions if any crack is found in the door jamb or jamb structure of a lower cargo door.

For Boeing Service Bulletin DC9-52-189, the corrective action includes the following:

• Repairing any crack found in the door outer skin.
• Replacing cracked parts, if cracks are found in the two adjacent beam end fittings; or if cracks are found in any beam end fitting with the intercostal web, angle, or tee fitting for any cracked upper or lower stop pad support fitting.
• Repetitively inspecting for crack growth and additional cracks, if cracks are found inside any pressure seal other than the outer pan; if multiple cracks totaling 10 inches or less are found inside the pressure seal of the outer pan; if no more than two cracks, each 1.25 inches or less in length, are found outside the pressure seal of the outer pan; or if only one crack 2.0 inches or less in length is found outside the pressure seal of the outer pan.
• Repairing any cracked outer pan, if multiple cracks totaling more than 10 inches are found inside the pressure seal of the outer pan; if more than 2 cracks, or any crack longer than 2.5 inches or two cracks with either one longer than 1.75 inches, are found outside the pressure seal of the outer pan; if no more than 2 cracks, each longer than 1.25 inches in length but less than 1.75 inches, are found outside the pressure seal of the outer pan; or if no more than one crack, longer than 2.0 inches in length but less than 2.5 inches, is found in the outer pressure boundary of the outer pan.

The service bulletins also describe the following procedures, which would end the applicable repetitive visual or repetitive eddy current inspections:

• Replacing all early configuration stop pad support fittings installed on any lower cargo door with new configuration or new stop pad support fittings.
• Reidentifying the applicable lower cargo door after replacement of the early configuration stop pad support fittings.

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

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to exist or develop on other airplanes of this same type design. Therefore, we are proposing this AD, which would require accomplishing the actions specified in the service information described previously, except as discussed under “Differences Between the Proposed AD and Service Bulletins.”

Differences Between the Proposed AD and Service Bulletins

The service bulletins specify that you may contact the manufacturer for instructions on how to repair certain conditions, but this proposed AD would require you to repair those conditions in one of the following ways:

• Using a method that we approve; or
• Using data that meet the certification basis of the airplane, and that have been approved by an Authorized Representative for the Boeing Delegation Option Authorization Organization whom we have authorized to make those findings.

For airplanes identified as Group 1 in Boeing Service Bulletin DC9-52-189, Revision 01, the service bulletin recommends doing the initial inspection of the lower cargo doors for cracks “* * * within the next 300 flight hours on airplanes having in excess of 8,000 flight hours, if not currently inspected * * * .” This proposed AD, however, would require a compliance time of within 300 flight hours after the effective date of this AD, since all Group 1 airplanes already have exceeded the 8,000 total-flight-hour threshold.

The service bulletins recommend not to remove and reinstall a lower cargo door on another airplane after that lower cargo door has been inspected in accordance with the applicable service bulletin. This proposed AD, however, does not prohibit reinstallation of a lower cargo door on another airplane. We have coordinated this difference with the manufacturer.

Clarification of Inspection Terminology

“Visually inspecting” as specified in the service bulletins is referred to as a “general visual inspection” in this proposed AD. We have included the definition for a general visual inspection in a note in this proposed AD.

Costs of Compliance

There are about 2,016 airplanes of the affected design in the worldwide fleet. The following table provides the estimated costs for U.S. operators, at an average labor rate of $65 per hour, to comply with this proposed AD.

Estimated Costs

Action	Work hours	Parts	Cost per airplane	Number of U.S.-registered airplanes	Fleet cost
Inspection to determine part numbers for Group 2, 3, and 4 airplanes identified in Boeing Service Bulletin DC9-52-189; Model MD-90-30 airplanes; and Model 717-200 airplanes	1	None	$65	1,218	$79,170
Inspection for cracks for Group 1 airplanes identified in Boeing Service Bulletin DC9-52-189, per inspection cycle	4	None	1$260	368	1$95,680
1 Per inspection cycle.

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

McDonnell Douglas: Docket No. FAA-2005-22254; Directorate Identifier 2005-NM-001-AD.

Comments Due Date

(a) The Federal Aviation Administration (FAA) must receive comments on this AD action by October 17, 2005.

Affected ADs

(b) Accomplishing paragraph (g) or (h), as applicable, of this AD terminates certain requirements of AD 96-10-11, amendment 39-9618, as specified in McDonnell Douglas DC-9 Service Bulletin 52-89, Revision 5, dated February 26, 1991.

Applicability

(c) This AD applies to the airplanes specified in paragraphs (c)(1) and (c)(2) of this AD, certificated in any category.

(1) All McDonnell Douglas Model DC-9-11, DC-9-12, DC-9-13, DC-9-14, DC-9-15, DC-9-15F, DC-9-21, DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F, DC-9-33F, DC-9-34, DC-9-34F, DC-9-32F (C-9A, C-9B), DC-9-41, and DC-9-51 airplanes; Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), DC-9-87 (MD-87) airplanes; Model MD-88 airplanes; and Model MD-90-30 airplanes; and

(2) Model 717-200 airplanes, as identified in Boeing Service Bulletin 717-52-0007, dated December 14, 2004.

Unsafe Condition

(d) This AD was prompted by a report of cracks found in the area of the upper and lower stop pad support fittings of the cargo door pan on numerous airplanes. We are issuing this AD to prevent cracks in the cargo door pan, which could result in the inability to fully pressurize an airplane and possible rapid decompression 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.

Service Bulletin References

(f) The term “service bulletin,” as used in this AD, means the following service bulletins, as applicable:

(1) For Model DC-9-11, DC-9-12, DC-9-13, DC-9-14, DC-9-15, DC-9-15F, DC-9-21, DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F, DC-9-33F, DC-9-34, DC-9-34F, DC-9-32F (C-9A, C-9B), DC-9-41, and DC-9-51 airplanes; Model DC-9-81 (MD-81) airplanes; Model DC-9-82 (MD-82), DC-9-83 (MD-83), DC-9-87 (MD-87) airplanes; and Model MD-88 airplanes: Boeing Service Bulletin DC9-52-189, Revision 01, excluding Appendix A, dated March 20, 2003;

(2) For Model MD-90-30 airplanes: Boeing Service Bulletin MD90-52-014, dated December 14, 2004; and

(3) For Model 717-200 airplanes: Boeing Service Bulletin 717-52-0007, dated December 14, 2004.

Determine Part Numbers (P/Ns) and Inspect if Necessary

(g) For airplanes identified in Table 1 of this AD: At the compliance time specified in Table 1 of this AD, inspect to determine the part number of the upper and lower stop pad support fittings of the lower cargo doors, in accordance with the Accomplishment Instructions of the service bulletin, as applicable. If new configuration or new upper and lower stop pad support fittings, as identified in the applicable service bulletin, are found installed on all lower cargo doors, then no further action is required by this paragraph. If any early configuration stop pad support fitting is found installed on any lower cargo door, within 300 flight hours, do the inspection specified in either paragraph (g)(1) or (g)(2) of this AD, in accordance with the Accomplishment Instructions of the service bulletin, until the replacement specified in paragraph (k) of this AD is accomplished.

(1) Do a general visual inspection for cracks in any lower cargo door having an early configuration stop pad support fitting. Repeat the general visual inspection thereafter at intervals not to exceed 1,700 flight hours.

(2) Do an eddy current inspection for cracks in any lower cargo door having an early configuration stop pad support fitting. Repeat the eddy current inspection thereafter at intervals not to exceed 3,900 flight hours.

Note 1:

For the purposes of this AD, a general visual inspection is: “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to ensure visual access to all surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.”

Table 1.—Compliance Times To Determine P/N

Applicable airplanes	Compliance time
Airplanes identified as Group 2, 3, and 4 in paragraph 1.D. of Boeing Service Bulletin DC9-52-189, Revision 01, dated March 20, 2003	Within 300 flight hours after the effective date of this AD.
Model MD-90-30 airplanes and Model 717-200 airplanes	Before the accumulation of 25,000 total flight hours, or within 3,900 flight hours after the effective date of this AD, whichever is later.

Repetitive Inspections for Certain Airplanes

(h) For airplanes identified as Group 1 in paragraph 1.D. of Boeing Service Bulletin DC9-52-189, Revision 01, dated March 20, 2003: At the applicable compliance time specified in Table 2 of this AD, do the inspection specified in either paragraph (g)(1) or (g)(2) of this AD, in accordance with the Accomplishment Instructions of the service bulletin. Repeat the inspection thereafter at the interval specified in paragraph (g)(1) or (g)(2), as applicable, until the replacement specified in paragraph (k) of this AD is accomplished. Inspections also may be done in accordance with the Accomplishment Instructions of McDonnell Douglas DC-9 Service Bulletin 52-89, Revision 5, dated February 26, 1991; or Revision 6, dated January 11, 1993.

Table 2.—Compliance Times for Inspection

For airplanes that have—	Compliance time
Been inspected before the effective date of this AD in accordance with paragraph (b) of AD 96-10-11 as specified in Phase I of the Accomplishment Instructions of McDonnell Douglas DC-9 Service Bulletin 52-89, Revision 5, dated February 26, 1991, or Revision 6, dated January 11, 1993	Within 1,700 flight hours after the last general visual inspection, or within 3,900 flight hours after the last eddy current inspection, as applicable.
Not been inspected before the effective date of this AD in accordance with paragraph (b) of AD 96-10-11 as specified in Phase I of the Accomplishment Instructions of McDonnell Douglas DC-9 Service Bulletin 52-89, Revision 5, dated February 26, 1991, or Revision 6, dated January 11, 1993	Within 300 flight hours after the effective date of this AD.

Corrective Actions for Certain Airplanes

(i) For Model MD-90-30 airplanes and Model 717-200 airplanes: If any crack is found in the door jamb or jamb structure of a lower cargo door during any inspection required by paragraph (g)(1) or (g)(2) of this AD, and the service bulletin specifies contacting Boeing for appropriate action, before further flight, repair the crack using a method in accordance with paragraph (o) of this AD.

Corrective Actions for Certain Other Airplanes

(j) For Model DC-9-11, DC-9-12, DC-9-13, DC-9-14, DC-9-15, DC-9-15F, DC-9-21, DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F, DC-9-33F, DC-9-34, DC-9-34F, DC-9-32F (C-9A, C-9B), DC-9-41, DC-9-51 airplanes; Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) airplanes; and Model MD-88 airplanes: If any crack is found during any inspection required by paragraph (g)(1), (g)(2), or (h) of this AD, do the corrective action at the applicable compliance time specified in paragraph 1.E. of the service bulletin, in accordance with the Accomplishment Instructions of the service bulletin, as applicable.

Optional Replacement of Stop Pad Support Fittings

(k) For all airplanes: Replacement of all early configuration stop pad support fittings installed on a lower cargo door with new configuration or new stop pad support fittings, as identified in the applicable service bulletin; and reidentification of the applicable lower cargo door; in accordance with the Accomplishment Instructions of the applicable service bulletin; terminates the repetitive inspections required by paragraphs (g)(1), (g)(2), and (h) of this AD, as applicable, for that lower cargo door only.

Parts Installation

(l) For all airplanes: As of the effective date of this AD, no person may install an early configuration stop pad support fitting having P/N 3925046-1, -501, -505, -507, or -509, or P/N 3926046-1 or -501, on any airplane.

Credit for Previous Service Bulletin

(m) Actions done before the effective date of this AD in accordance with Boeing Service Bulletin DC9-52-189, dated August 10, 2001, are acceptable for compliance with the corresponding requirements of this AD.

Terminating Action for Certain Requirements of AD 96-10-11

(n) For Model DC-9-11, DC-9-12, DC-9-13, DC-9-14, DC-9-15, DC-9-15F, DC-9-21, DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F, DC-9-33F, DC-9-34, DC-9-34F, DC-9-32F (C-9A, C-9B), DC-9-41, and DC-9-51 airplanes: Accomplishing the replacement specified in paragraph (k) of this AD for the forward and aft lower cargo doors terminates the repetitive inspections of the forward and aft lower cargo doors for cracks required by paragraph (b) of AD 96-10-11 as specified in McDonnell Douglas DC-9 Service Bulletin 52-89, Revision 5, dated February 26, 1991.

Alternative Methods of Compliance (AMOCs)

(o)(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) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD, if it is approved by an Authorized Representative for the Boeing Commercial Airplanes Delegation Option Authorization Organization who has been authorized by the Manager, Los Angeles ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane and 14 CFR 25.571, Amendment 45, and the approval must specifically refer to this AD.

Issued in Renton, Washington, on August 24, 2005.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.