Airworthiness Directives; Letecké Závody Model L 23 Super-Blanik Sailplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for certain Letecké Závody Model L 23 Super-Blanik sailplanes. This proposed AD would require you to do a repetitive, non-destructive magnetic test (NDMT) inspection on the elevator rocker lever (part number A 730 201 N) for cracks. If cracks are found, this proposed AD would also require you to return the part to the manufacturer. The manufacturer will send you a replacement part for installation. Installing the improved replacement part would terminate the need for the repetitive inspections. This proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for the Czech Republic. We are issuing this proposed AD to prevent failure of the elevator rocker lever caused by cracks that resulted from a defect in prior manufacturing procedures. Such failure could lead to loss of control of the sailplane.

DATES:

We must receive any comments on this proposed AD by October 4, 2004.

ADDRESSES:

Use one of the following 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 20590-001.
• 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.

You may get the service information identified in this proposed AD from Letecké Závody a.s., 686 04 Kunovice 1177, Czech Republic.

You may view the comments to this proposed AD in the AD docket on the Internet at http://dms.dot.gov.

FOR FURTHER INFORMATION CONTACT:

Gregory A. Davison, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: (816) 329-4130; facsimile: (816) 329-4090.

SUPPLEMENTARY INFORMATION:

Comments Invited

How do I comment on this proposed AD? We invite you to submit any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include the docket number, “FAA-2004-18034; Directorate Identifier 2004-CE-18-AD” at the beginning of your 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 rulemaking. Using the search function of our docket Web site, anyone can find and read the comments received into 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.). This is docket number FAA-2004-18034. 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.

Are there any specific portions of this proposed AD I should pay attention to? We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. If you contact us through a nonwritten communication and that contact relates to a substantive part of this proposed AD, we will summarize the contact and place the summary in the docket. We will consider all comments received by the closing date and may amend this proposed AD in light of those comments and contacts.

Docket Information

Where can I go to view the docket information? You may view the AD docket that contains the proposal, any comments received, and any final disposition in person at the DMS Docket Offices between 9 a.m. and 5 p.m. (eastern standard time), Monday through Friday, except Federal holidays. The Docket Office (telephone (800) 647-5227) is located on the plaza level of the Department of Transportation NASSIF Building at the street address stated in ADDRESSES. You may also view the AD docket on the Internet at http://dms.dot.gov. The comments will be available in the AD docket shortly after the DMS receives them.

Discussion

What events have caused this proposed AD? The Civil Aviation Authority (CAA), which is the airworthiness authority for the Czech Republic, recently notified FAA that an unsafe condition may exist on certain Letecké Závody Model L 23 Super-Blanik sailplanes. The CAA reports that, during an accident investigation, cracks were found on the elevator rocker lever.

The manufacturer has identified a problem with its quality control inspection procedures during the production of the original elevator rocker lever part prior to January 2004. Micro-cracks or voids were not detected when the parts left production and were installed on the affected sailplanes. These discrepancies may cause fatigue failure of the elevator rocker lever.

In January 2004, the manufacturer changed its manufacturing process and is currently replacing any existing defective elevator rocker levers within the specified affected sailplanes.

What is the potential impact if FAA took no action? If not detected and corrected, cracks in the elevator rocker lever could cause the lever to fail. Such failure could result in loss of control of the sailplane.

Is there service information that applies to this subject? Letechké Závody has issued Mandatory Bulletin MB No.: L23/48a, not dated.

What are the provisions of this service information? The service bulletin includes procedures for:

—Doing a non-destructive magnetic test inspection on the elevator rocker lever (part number A 730 201 N) for cracks; and

—Returning all cracked elevator rocker levers to the manufacturer to get a replacement part for installation.

What action did the CAA take? The CAA classified this service bulletin as mandatory and issued Czech Republic AD Number CAA-AD-T-005/2004, dated January 16, 2004, to ensure the continued airworthiness of these sailplanes in the Czech Republic.

Did the CAA inform the United States under the bilateral airworthiness agreement? These Letecké Závody Model L 23 Super-Blanik sailplanes are manufactured in the Czech Republic and are type-certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement.

Under this bilateral airworthiness agreement, the CAA has kept us informed of the situation described above.

FAA's Determination and Requirements of This Proposed AD

What has FAA decided? We have examined the CAA's findings, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

Since the unsafe condition described previously is likely to exist or develop on other Letecké Závody Model L 23 Super-Blanik sailplanes of the same type design that are registered in the United States, we are proposing AD action to prevent failure of the elevator rocker lever caused by cracks. This failure could lead to loss of control of the sailplane.

What would this proposed AD require? This proposed AD would require you to incorporate the actions in the previously-referenced service bulletin.

What is the difference between this proposed AD and the CAA AD? The CAA AD requires doing the initial inspection prior to further flight after the effective date of the AD. We propose a requirement that you do the initial inspection within the next 25 hours time-in-service (TIS) after the effective date of this proposed AD.

We do not have justification to require this action prior to further flight. We use compliance times such as this when we have identified an urgent safety of flight situation. We believe that 25 hours TIS will give the owners or operators of the affected sailplanes enough time to have the proposed actions required by this AD done without compromising the safety of the sailplanes.

How does the revision to 14 CFR part 39 affect this proposed AD? On July 10, 2002, we published a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs FAA's AD system. This regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance. This material previously was included in each individual AD. Since this material is included in 14 CFR part 39, we will not include it in future AD actions.

Costs of Compliance

How many sailplanes would this proposed AD impact? We estimate that this proposed AD affects 103 sailplanes in the U.S. registry.

What would be the cost impact of this proposed AD on owners/operators of the affected sailplanes? We estimate the following costs to accomplish the proposed inspections:

We estimate the following costs to accomplish any necessary replacements that would be required based on the results of the proposed inspections. We have no way of determining the number of sailplanes that may need this replacement:

Regulatory Findings

Would this proposed AD impact various entities? 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.

Would this proposed AD involve a significant rule or regulatory action? For the reasons discussed above, I certify that this proposed AD:

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 summary of the costs to comply with this proposed AD and placed it in the AD Docket. You may get a copy of this summary by sending a request to us at the address listed under ADDRESSES. Include “AD Docket No. 2004-CE-18-AD” in your request.

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 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.