Airworthiness Directives; The New Piper Aircraft, Inc. Models PA-31, PA-31-300, PA-31-325, PA-31-350, PA-31P, PA-31T, PA-31T1, PA-31T2, PA-31T3, and PA-31P-350 Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes to supersede three existing airworthiness directives (AD's) that apply to certain The New Piper Aircraft, Inc. (Piper) Models PA-31, PA-31-300, PA-31P, PA-31T, and PA-31T1 airplanes. These AD's currently require you to repetitively inspect and/or modify the elevator structure. The proposed AD would: initially retain the inspection and modification requirements that are currently required; add certain other airplane models to the AD applicability; and require a modification at a certain time period, as terminating action for the currently required repetitive inspections. This action coincides with the Federal Aviation Adminstration's policy of incorporating modifications, when available, that will terminate the need for repetitive inspections. The actions specified by the proposed AD are intended to continue to detect and correct damage to the elevator structure. A damaged elevator structure could lead to reduced or loss of control of the airplane.

DATES:

The Federal Aviation Administration (FAA) must receive any comments on this rule on or before September 8, 2000.

ADDRESSES:

Submit comments in triplicate to FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 99-CE-29-AD, 901 Locust, Room 506, Kansas City, Missouri 64106. You may get the service information referenced in the proposed AD from The New Piper Aircraft, Inc., Customer Services, 2926 Piper Drive, Vero Beach, Florida 32960. You may examine this information at FAA.

FOR FURTHER INFORMATION CONTACT:

William O. Herderich, Aerospace Engineer, FAA, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia 30349; telephone: (770) 703-6084; facsimile: (770) 703-6097; e-mail: william.o.herderich@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

How do I comment on this AD? We invite your comments on the proposed rule. You may submit whatever written data, views, or arguments you choose. You need to include the rule's docket number and submit your comments in triplicate to the address specified under the caption ADDRESSES. We will consider all comments received on or before the closing date specified above, before acting on the proposed rule. We may change the proposals contained in this notice in light of the comments received.

How can we communicate more clearly with you? The FAA is reviewing the writing style we currently use in regulatory documents, in response to the Presidential memorandum of June 1, 1998. That memorandum requires federal agencies to communicate more clearly with the public. We are interested in your comments on the ease of understanding this document, and any other suggestions you might have to improve the clarity of FAA communications that affect you. You can get more information about the Presidential memorandum and the plain language initiative at http://www.faa.gov/language/.

The FAA specifically invites comments on the overall regulatory, economic, environmental, and energy aspects of the proposed rule that might necessitate a need to modify the proposed rule. You may examine all comments we receive. We will file a report in the Rules Docket that summarizes each FAA contact with the public that concerns the substantive parts of this proposal.

How can I be sure FAA receives my comment? If you want us to acknowledge the receipt of your comments, you must include a self-addressed, stamped postcard. On the postcard, write “Comments to Docket No. 99-CE-29-AD.” We will date stamp and mail the postcard back to you.

Discussion

Has FAA taken any action to this point? The following AD's currently require you to repetitively inspect and/or modify the elevator structure on certain Piper Models PA-31, PA-31-300, PA-31P, PA-31T, and PA-31T1 airplanes.

—AD 70-26-06, Amendment 39-1132, which requires you to repetitively inspect the elevator structure on Piper Models PA-31 and PA-31-300 airplanes, serial numbers 31-2 through 31-694. The AD requires you to modify the elevator structure if cracks are found;

—AD 76-03-01, Amendment 39-2505, which requires you to modify the elevator structure on Piper Models PA-31T airplanes, serial numbers 31T-7400002 through 31T-7620007. This AD requires you to inspect the elevator support and replace any defective parts on Piper Model PA-31T airplanes, serial numbers 31T-7400002 through 31T-7520020, 31T-7520022 through 31T-7520038; and 31T-7520040 through 31T-760012; and

—AD 80-02-15, Amendment 39-3676, which requires you to inspect and alter the elevator structure and replace any defective parts on Piper Model PA-31P airplanes, serial numbers 31P-1 through 31P-7730012; Model PA-31T airplanes, serial numbers 31T-7400002 through 31T-7920075; and Model PA-31T1 airplanes, serial numbers 31T-7804001 through 31T-7904036 and 31T-7904038 through 31T-7904044.

What has happened to necessitate further AD action? Piper has informed FAA of reports of damage in the elevator structure area on additional airplanes. These are Piper Models PA-31-325, PA-31-350, PA-31T3, and PA-31P-350 airplanes.

On December 24, 1996, FAA issued a special airworthiness information bulletin (SAIB) to encourage compliance with new service information related to the elevator structure on the above-referenced airplanes. We continue to receive reports of damage in the elevator structure area on these airplanes.

Relevant Service Information

Is there service information that applies to this subject? Piper has issued the following:

—Service Bulletin No. 323, dated September 21, 1970;

—Service Bulletin No. 897B, Date: July 15, 1997; and

—Service Bulletin No. 1008, Date: September 30, 1997.

What are the provisions of these service bulletins? These service bulletins specify and include procedures for the following:

The FAA's Determination and an Explanation of the Provisions of the Proposed AD

What has FAA decided? After examining the circumstances and reviewing all available information related to the incidents described above, including the relevant service information, we have determined that:

—an unsafe condition is likely to exist or develop on Piper Models PA-31, PA-31-300, PA-31-325, PA-31-350, PA-31P, PA-31T, PA-31T1, PA-31T2, PA-31T3, and PA-31P-350 of the same type design;

—the actions of the above-referenced service bulletins should be accomplished on the affected airplanes; and

—AD action should be taken to detect and correct damage to the elevator structure. A damaged elevator structure could lead to reduced or loss of control of the airplane.

What are the provisions of the proposed AD? The proposed AD would supersede AD 70-26-06, AD 76-03-01, and AD 80-02-15, with a new AD that would:

—initially retain the inspection and modification requirements that are currently required;

—add certain other airplane models to the AD applicability; and

—require a modification at a certain time period, as terminating action for the currently required repetitive inspections.

Does this proposed AD follow FAA's aging commuter-class aircraft policy? The actions proposed in this NPRM are consistent with FAA's aging commuter aircraft policy, which briefly states that, when a modification exists that could eliminate or reduce the number of required critical inspections, the modification should be incorporated. This policy is based on our determination that reliance on critical repetitive inspections on airplanes utilized in commuter service carries an unnecessary safety risk when a design change exists that could eliminate or, in certain instances, reduce the number of those critical inspections. In determining what inspections are critical, we consider (1) the safety consequences of the airplane if the known problem is not detected by the inspection; (2) the reliability of the inspection such as the probability of not detecting the known problem; (3) whether the inspection area is difficult to access; and (4) the possibility of damage to an adjacent structure as a result of the problem.

The alternative to modifying the elevator structure on the affected airplanes would be to require you to repetitively inspect this area for the life of the airplane.

Cost Impact

How many airplanes does this proposed AD impact? We estimate that 2,344 airplanes in the U.S. registry would be affected by the proposed AD.

What is the cost impact of the proposed modification for affected airplanes on the U.S. Register? We estimate that it would take approximately 20 workhours per airplane to accomplish the proposed modification, at an average labor rate of $60 an hour. Parts to accomplish the proposed modification cost approximately $600 per airplane.

Based on these figures, FAA estimates the cost to accomplish the proposed modification at $4,219,200, or $1,800 per airplane.

What is the cost impact of the proposed inspections for affected airplanes on the U.S. Register? We estimate that it would take approximately 8 workhours per airplane to accomplish each proposed inspection, at an average labor rate of $60 an hour. Based on these figures, FAA estimates the cost to accomplish each proposed inspection at $480 per airplane. Accomplishment of the proposed modification would eliminate the need for the proposed inspections.

Regulatory Impact

How does this AD impact relations between Federal and State governments? The proposed regulations 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. We have determined that this proposed rule would not have federalism implications under Executive Order 13132.

How does this AD involve a significant rule or regulatory action? For the reasons discussed above, I certify that this action (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) if put into effect, 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 have placed a copy of the draft regulatory evaluation prepared for this action in the Rules Docket. You may obtain a copy of it 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, under the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 14 CFR part 39 of the Federal Aviation Regulations 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.