AGENCY:
Federal Aviation Administration (FAA), Department of Transportation (DOT).
ACTION:
Notice of proposed rulemaking (NPRM).
SUMMARY:
The FAA proposes to supersede an existing airworthiness directive (AD) that applies to certain McDonnell Douglas Model DC-9-10, -20, -30, -40 and -50 series airplanes, and Model DC-9-81 (MD-81), and DC-9-82 (MD-82) airplanes. That AD currently requires installing a water drain system for the slant pressure panels in the left and right wheel wells of the main landing gear (MLG). This proposed AD would also require inspecting the seal assemblies of the overwing emergency exit doors for defects and constant gap; replacing defective door seals; performing repetitive operational checks of the water drain system auto drain valve and corrective actions if necessary; and, for certain airplanes, modifying the insulation blankets on the slant pressure panels in the left and right MLG wheel wells. This proposed AD is prompted by reports of water runoff from the slant pressure panels in the left and right MLG wheel wells, which subsequently froze on the lateral control mixer and control cable assemblies. We are proposing this AD to prevent ice from forming on the lateral control mixer and control cable assemblies, which could reduce controllability of the airplane.
DATES:
We must receive comments on this proposed AD by October 3, 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.
- Fax: (202) 493-2251.
- 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-2005-22121; the directorate identifier for this docket is 2004-NM-128-AD.
FOR FURTHER INFORMATION CONTACT:
Wahib Mina, Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone (562) 627-5324; fax (562) 627-5210.
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-2005-22121; Directorate Identifier 2004-NM-128-AD” at the beginning 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 received 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 our docket 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 the 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 (800) 647-5227) 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
On June 29, 1993, we issued AD 93-13-07, amendment 39-8620 (58 FR 38511, July 19, 1993), for certain McDonnell Douglas Model DC-9-10, -20, -30, -40 and -50 series airplanes, Model DC-9-81 and DC-9-82 airplanes, and Model C-9 (Military) airplanes. That AD requires installing a water drain system for the slant pressure panels in the left and right wheel wells of the main landing gear (MLG). That AD was prompted by reports of water freezing on the control cables. We issued that AD to prevent water from draining into the wheel wells and subsequently freezing, which could restrict the movement of the control cables and lead to reduced controllability of the airplane.
Actions Since Existing AD Was Issued
Since we issued AD 93-13-07, we received a report of in-flight loss of aileron control on a Model DC-9-32 airplane. Investigation revealed that, due to failure of the auto drain valve in the drain system installed by AD 93-13-07, water accumulated at the slant pressure panels and subsequently froze, forming ice around the aileron control cables and pulleys in the MLG wheel wells.
Relevant Service Information
We have reviewed Boeing Service Bulletin DC9-53-179, Revision 2, dated May 27, 2004 (the original issue, dated January 18, 1985, is referenced as the appropriate source of service information for accomplishing AD 93-13-07). The procedures described in Revision 2 of the service bulletin are essentially the same, except for the addition of procedures for performing a visual inspection for defects and constant gap of the seal assemblies of the overwing emergency exit doors, and replacing defective door seals with new door seals. The service bulletin also describes procedures for revising the maintenance program by adding on-aircraft maintenance program reports (OAMP) relating to repetitive operational checks of the auto drain valve of the water drain system in the slant pressure panel.
Boeing Service Bulletin DC9-53-179, Revision 2, specifies prior or concurrent accomplishment of McDonnell Douglas Service Bulletin DC9-53-268, on certain airplanes.
We have reviewed McDonnell Douglas Service Bulletin DC9-53-268 R01, Revision 01, dated July 18, 1996, which describes procedures for modifying the insulation blankets on the slant pressure panels in the left and right wheel wells of the MLG.
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
The unsafe condition described previously is likely to exist or develop on other airplanes of this same type design. Therefore, we are proposing this AD, which would supersede AD 93-13-07. This proposed AD would retain the requirements of the existing AD. This proposed AD would also require inspecting the seal assemblies of the overwing emergency exit doors for defects and constant gap; replacing defective door seals; performing repetitive operational checks of the water drain system auto drain valve and corrective actions if necessary; and, for certain airplanes, modifying the insulation blankets on the slant pressure panels in the left and right MLG wheel wells. This proposed AD would require you to use the service information described previously to perform these actions, except as discussed under “Differences Between the Proposed AD and Referenced Service Bulletins.”
Differences Between the Proposed AD and Referenced Service Bulletins
Although the service bulletins recommend accomplishing the modifications “* * * at the earliest practical maintenance period * * *,” we have determined that this imprecise compliance time would not address the identified unsafe condition in a timely manner. In developing an appropriate compliance time for this AD, we considered not only the manufacturer's recommendation, but the degree of urgency associated with addressing the subject unsafe condition, the average utilization of the affected fleet, and the time necessary to perform the modifications. In light of all of these factors, we find a compliance time of 24 months for completing the required actions to be warranted, in that it represents an appropriate interval of time for affected airplanes to continue to operate without compromising safety. This difference has been coordinated with Boeing.
Where Boeing Service Bulletin DC9-53-179, Revision 2, specifies prior or concurrent accomplishment of McDonnell Douglas Service Bulletin DC9-53-268 R01 on certain airplanes, this proposed AD would, under certain circumstances, allow accomplishment of Service Bulletin DC9-53-268 R01 within 24 months after the effective date of this proposed AD. We find that this compliance time would prevent the immediate grounding of any airplane.
As discussed under “Relevant Service Information,” Boeing Service Bulletin DC9-53-179, Revision 2, describes procedures for adding certain OAMPs to the maintenance programs. These OAMPs relate to repetitive operational checks of the auto drain valve and replacing any auto drain valve found to be obstructed or inoperative with a new auto drain valve. This proposed AD would not require you to revise the maintenance programs as described; rather, this proposed AD would require you to perform the repetitive operational checks and any auto drain valve replacement, in accordance with a method approved by the FAA. Chapter 51-10-01 of the Boeing MD-80 Aircraft Maintenance Manual is one approved method of performing these actions.
Clarification of Inspection Terminology
The service information specifies to “inspect” the seal assemblies of the overwing emergency exit doors for defects and constant gap. To prevent any confusion about the proper type of inspection, this proposed AD would require a general visual inspection. We have included a definition of this type of inspection in this proposed AD.
Clarification of Change to Applicability of Existing AD
We have revised the applicability of the existing AD to identify model designations as published in the most recent type certificate data sheet for the affected models.
Costs of Compliance
There are about 2,025 airplanes of the affected design in the worldwide fleet. There are about 1,131 airplanes of U.S. registry that would be affected by this proposed AD. The following table provides the estimated costs, using an average labor rate of $65 per hour, for U.S. operators to comply with this proposed AD.
Estimated Costs
Action | Work hours | Parts | Cost per airplane | Fleet cost |
---|---|---|---|---|
Install water drain system (required by AD 93-13-07) | 8 | $613 | $1,133 | $1,281,423 |
Inspect overwing emergency exit door seal assemblies (new proposed action) | 1 | N/A | 65 | 73,515 |
Modify insulation blankets of slant pressure panel (new proposed action) | 8 | N/A | 520 | N/A |
Check auto drain valve of slant pressure panel water drain system (new proposed action) | 1 | N/A | * 65 | 73,515 |
* 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.
2. The FAA amends § 39.13 by removing amendment 39-8620 (58 FR 38511, dated July 19, 1993) and adding the following new airworthiness directive (AD):
McDonnell Douglas: Docket No. FAA-2005-22121; Directorate Identifier 2004-NM-128-AD.
Comments Due Date
(a) The Federal Aviation Administration must receive comments on this AD action by October 3, 2005.
Affected ADs
(b) This AD supersedes AD 93-13-07, amendment 39-8620.
Applicability
(c) This AD applies to 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, DC-9-51, DC-9-81 (MD-81), and DC-9-82 (MD-82) airplanes; as identified in Boeing Service Bulletin DC9-53-179, Revision 2, dated May 27, 2004; certificated in any category.
Unsafe Condition
(d) This AD was prompted by reports of water runoff from the slant pressure panels in the left and right main landing gear (MLG) wheel wells, which subsequently froze on the lateral control mixer and control cable assemblies. We are issuing this AD to prevent ice from forming on the lateral control mixer and control cable assemblies, which could reduce controllability 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.
Restatement of Requirements of AD 93-13-07
Installation of Water Drain System
(f) Within 24 months after August 18, 1993 (the effective date of AD 93-13-07), install a water drain system in the slant pressure panel, in accordance with McDonnell Douglas DC-9 Service Bulletin 53-179, dated January 18, 1985, as amended by Service Bulletin Change Notification 53-179 CN1, dated February 28, 1985, and Service Bulletin Change Notification 53-179 CN2, dated May 30, 1985; or in accordance with McDonnell Douglas Service Bulletin DC-9-53-179, Revision 01, dated March 30, 1999; or Boeing Service Bulletin DC9-53-179, Revision 2, dated May 27, 2004. After the effective date of this AD, only Boeing Service Bulletin DC9-53-179, Revision 2, dated May 27, 2004, may be used.
New Requirements of This AD
Inspection of Door Seal Assemblies
(g) For all airplanes: Within 24 months after the effective date of this AD, perform a general visual inspection of the seal assemblies of the overwing emergency exit doors for defects and constant gap, and, before further flight, replace any defective door seal with a new door seal; in accordance with the Accomplishment Instructions of Boeing Service Bulletin DC9-53-179, Revision 2, dated May 27, 2004.
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.”
Inspections Already Accomplished
(h) Inspections accomplished before the effective date of this AD in accordance with McDonnell Douglas Service Bulletin DC9-53-179, Revision 01, dated March 30, 1999; are considered acceptable for compliance with the requirements of paragraph (g) of this AD.
Operational Check of Drain Valve
(i) For all airplanes: Within 24 months after the effective date of this AD, perform an operational check of the auto drain valve of the slant pressure panel water drain system and repeat this check every 24 months. If any auto drain valve is found to be obstructed or inoperative, before further flight, replace the auto drain valve with a new auto drain valve according to a method approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA. Chapter 51-10-01 of the Boeing MD-80 Aircraft Maintenance Manual is one approved replacement method.
Note 2:
After an operator complies with the requirements of paragraph (h) of this AD, paragraph (h) does not require that operators subsequently record accomplishment of those requirements each time a auto drain valve is checked or replaced according to that operator's FAA-approved maintenance inspection program.
Concurrent Service Bulletin
(j) For airplanes identified in McDonnell Douglas Service Bulletin DC9-53-268 R01, Revision 01, dated July 18, 1996: At the applicable compliance time specified in paragraph (j)(1) or (j)(2) of this AD, modify the insulation blankets on the slant pressure panels in the left and right wheel wells of the MLG, in accordance with the service bulletin.
(1) For airplanes which have been modified, as specified in paragraph (f) of this AD, prior to the effective date of this AD: Within 24 months after the effective date of this AD.
(2) For airplanes which have not been modified, as specified in paragraph (f) of this AD, prior to the effective date of this AD: Prior to or concurrently with the accomplishment of paragraph (f) of this AD.
Alternative Methods of Compliance (AMOCs)
(k)(1) The Manager, Los Angeles ACO, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.
(2) AMOCs approved previously according to AD 93-13-07 are approved as AMOCs for the corresponding requirements of this AD.
Issued in Renton, Washington, on August 10, 2005.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 05-16363 Filed 8-17-05; 8:45 am]
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