Airworthiness directives: REVO, Inc.,

[Federal Register: May 26, 2000 (Volume 65, Number 103)]

[Rules and Regulations]

[Page 34065-34069]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr26my00-11]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-CE-27-AD; Amendment 39-11746; AD 2000-10-22]

RIN 2120-AA64

Airworthiness Directives; REVO, Incorporated Models Lake LA-4, Lake LA-4A, Lake LA-4P, Lake LA-4-200, and Lake Model 250 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

SUMMARY: This amendment adopts a new airworthiness directive (AD) that applies to certain REVO, Incorporated (REVO) Models Lake LA-4, Lake LA- 4A, Lake LA-4P, Lake LA-4-200, and Lake Model 250 airplanes. This AD requires you to: inspect the left and right wing upper and lower spar doublers for cracks; replace any cracked parts; and incorporate a modification kit. This AD is the result of a report of a fatigue crack found at the second most inboard wing attachment bolt hole on one of the affected airplanes. Similar fatigue cracking has since been reported on seven more of the affected airplanes, including incidents where the fatigue cracking occurred on airplanes with less than 500 hours time-in-service (TIS). The actions specified by this AD are intended to detect and correct cracks in the wing spars, which could result in the wing separating from the airplane with consequent loss of control.

DATES: This AD becomes effective on June 20, 2000.

The Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulation as of June 20, 2000.

The Federal Aviation Administration (FAA) must receive any comments on this rule on or before July 28, 2000.

ADDRESSES: Submit comments in triplicate to the FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 99-CE-27- AD, 901 Locust, Room 506, Kansas City, Missouri 64106.

You may get the service information referenced in this AD from REVO, Incorporated, P.O. Box 312, One High Street, Sanford, Maine 04073. You may examine this information at FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 99-CE-27-AD, 901 Locust, Room 506, Kansas City, Missouri 64106; or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Mr. Richard B. Noll, Aerospace Engineer, FAA, Boston Aircraft Certification Office, 12 New England Executive Park, Burlington, Massachusetts 01803; telephone: (781) 238- 7160; facsimile: (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Discussion

What Caused This AD?

This AD is the result of a report of fatigue cracks that were found at the second-most inboard wing attachment bolt hole on a REVO Lake Model 250 airplane. The cracks were detected during wing repair where the wing spar and wing skin were disassembled. Further analysis indicated that the cracks initiated at a machined notch at the flange termination point of the spar cap.

The REVO Models Lake LA-4, Lake LA-4A, Lake LA-4P, and Lake LA-4- 200 airplanes are of the same type design as the Lake Model 250 airplanes. Fatigue cracking similar to that of the above-referenced report has been found on seven more of these airplanes.

What Is the Potential Impact If FAA Took No Action?

Cracks in the wing spars, if not detected and corrected in a timely manner, could result in the wing separating from the airplane with consequent loss of control.

Has FAA Taken Any Action to This Point?

We issued a notice of proposed rulemaking (NPRM) to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to certain REVO Models Lake LA-4, Lake LA-4A, Lake LA- 4P, Lake LA-4-200, and Lake Model 250 airplanes. We published this NPRM in the Federal Register on October 6, 1999 (64 FR 54234). The NPRM proposed to require you to accomplish the following:

--Inspect the left and right wing upper and lower spar caps and doublers for cracks; --Replace any cracked parts; --Incorporate a modification kit if damaged past a certain level; and --Report the results of the inspection to FAA.

REVO Service Bulletin B-79, dated June 12, 1999, includes the procedures necessary for you to accomplish the proposed inspection and modification.

Was the Public Invited To Comment?

The FAA offered interested persons the opportunity to participate in the making of this amendment. The following paragraphs present the comments received on the NPRM. Also included is FAA's response to each comment, including any changes incorporated into the final rule based on the comments. Comment Issue No. 1: Wing Spar Cracking Does Not Warrant AD Action

What are the Commenters' Concerns? Numerous commenters question FAA's justification for issuing an AD. Several commenters do not believe our service difficulty database provides accurate information. A few commenters recommend that we conduct additional research on the cause of the wing spar cracks and determine if the cracks are unique to a particular configuration of the affected airplanes. Other commenters propose various causes of the cracks, including:

--Installation of auxiliary fuel tanks in the wing floats; --Increased braking power in the Model Lake LA-4-200 and Lake Model 250 airplanes; and --The presence of corrosion.

What is FAA's Response to the Concerns? We do not concur that the AD is not justified. We began our investigation of the wing spar cracks on the affected airplanes when the Australian Civil Aviation Safety Authority reported cracks in both the spar cap and doubler in the lower spar of a Lake Model 250 airplane. We then received several reports of similar cracking from personnel of maintenance and repair facilities that were working on the affected airplanes. Reports indicated that both the upper and lower spars were cracked. These subsequent reports did not specify corrosion damage. All of the wing spar cracks initiated at a machined notch at the flange termination point of the spar cap

[[Page 34066]]

at the second-most inboard wing attachment bolt hole.

We also initiated laboratory examinations of the cracked spars. These examinations revealed that fatigue caused the cracks and were associated with the roughness of the notch area. The certification basis for the affected airplanes did not require an evaluation of fatigue characteristics. A database of either analytical results or test data does not exist. However, we performed a fatigue analysis of the affected airplanes in the notch area in developing the proposed inspection compliance times. Our analysis of this situation included working with the manufacturer to develop inspection procedures for the spar doublers and spar cap angles and a modification (doubler kit) for the wing spar. We then determined that enough information existed to implement AD action in order to assure the continued airworthiness of the affected airplanes. Thus, we issued an NPRM to propose inspections for cracks and repair, replacement, and modification, as necessary.

We are not changing the AD as a result of these comments. Comment Issue No. 2: Do Not Require the Spar Cap Inspection

What are the Commenters' Concerns? Several commenters recommend that FAA not require the spar cap inspection in accordance with REVO, Inc. Service Bulletin B-79, dated June 12, 1999. The commenters offer the following explanations for eliminating this inspection:

--Accomplishing the inspection could cause damage to the spar cap/ doubler; --The number of personnel with the expertise necessary to accomplish the inspection is limited; --The fluorescent dye penetrant inspection is difficult to implement and is less effective than a visual or borescope examination; and --There are limited maintenance/repair facilities capable of conducting the inspection.

What are FAA's Responses to the Concerns? We concur that the spar cap inspection is not necessary. The inspection of the spar cap was intended to look for additional cracks outside of the notch area. We are eliminating the spar cap inspection from the AD for the following reasons:

--The cracks detected on the previously-referenced airplanes developed in the notch area and not in the spar cap; and --We have received several additional reports of airplanes with cracks in the notch area and nowhere else.

We are only requiring a visual inspection of the wing spar doublers instead of a dye penetrant inspection. REVO, Inc. has revised Service Bulletin B-79 (R1--Revised January 5, 2000) to incorporate the visual inspection change. Comment Issue No. 3: Provide Alternatives to the Proposed Requirements

What are the Commenters' Concerns? Several commenters recommend alternative methods of compliance to meet the safety intent of the AD. These alternatives are:

--Accomplish the inspection utilizing borescope procedures; --Accomplish the inspection utilizing visual procedures; --Only inspect the bolt holes; --Cut inspection holes in the wing skin; and --Allow repetitive inspections instead of requiring the incorporation of the Aerofab B-79 kit.

What is FAA's Response to the Concerns? We do not concur that any of the alternatives alone are valid to meet the safety intent of this AD. Inspecting the wing spar doubler in accordance with the procedures in REVO, Inc. Service Bulletin B-79, dated June 12, 1999, assures the airworthiness of this component prior to installing the doubler kit (Aerofab B-79 kit). Installing this doubler kit gives the spar an adequate fatigue life and eliminates the need for repetitive inspections. We do not concur that cutting holes in the wing skin for inspections is an acceptable alternative because of the sensitive nature of the wing skin.

We also do not concur with allowing repetitive inspections instead of mandatory incorporation of the Aerofab B-79 kit. Constant removal of the bolts could cause unnecessary damage. The FAA's policy is to require a modification when incorporation of that modification could eliminate or reduce the number of required inspections.

We are not changing the AD as a result of these comments. Comment Issue No. 4: Eliminate Certain Airplanes From the Applicability of the AD

What are the Commenters' Concerns? Several commenters request that FAA not include the Model Lake LA-4 airplanes in the applicability of the final rule AD. The commenters state that the applicability should be based on the weight, auxiliary fuel, and brake differences of the airplanes.

One commenter concurs with the applicability of the NPRM.

What is FAA's Response to the Concerns? We have determined that this AD should apply to the Model Lake LA-4 airplanes. The service difficulty database clearly shows the need to address the wing spar condition on the Model Lake LA-4-200 and Lake Model 250 airplanes. The Model Lake LA-4 airplanes are included because:

--The wing/spar attachment design is the same as the Model Lake LA-4- 200 airplanes; --The gross weight is only 200 pounds less than the Model Lake LA-4-200 airplanes; and --These airplanes have been in service longer than the Model Lake LA-4- 200 airplanes.

For these reasons, we have determined that the Model Lake LA-4 airplanes are also susceptible to wing spar fatigue cracking and the AD must apply to these airplanes.

We are not changing the AD as a result of these comments. Comment Issue No. 5: Revise the Methods of Incorporating the Doubler Kit

What are the Commenters' Concerns? Several commenters suggest revisions to the Aerofab B-79 doubler kit. These suggestions include:

1. Revising the rivet removal method; 2. Utilizing bolts instead of rivets; 3. Retaining the original bolts for the Model Lake LA-4 airplanes; and 4. Redesigning the doubler.

   What are FAA's Responses to the Concerns? We concur with these suggestions, as follows:

1. We concur and will require accomplishment in accordance with Revo, Inc. Service Bulletin B-79 R1, Revised January 5, 2000. This revised service bulletin incorporates the proposed rivet removal methods;

2. We concur. Revo, Inc. Service Bulletin B-79 R1, Revised January 5, 2000, allows the use of AN3 bolts, and accomplishment of the AD is required in accordance with this service bulletin;

3. We do not concur that you may retain the original bolts for the Model Lake LA-4 airplanes. The new design configuration of the wing spar caps with the doublers requires longer bolts than originally utilized; and

4. We do not concur with the need to redesign the doubler. Incorporation of the doubler kit on the affected airplanes restores wing spars to their required strength if a crack is present in the notch area of a spar cap. Incorporation of the doubler kit also provides the strength and stability to prevent future fatigue cracking.

   [[Page 34067]]

   Comment Issue No. 6: Difference Between the Proposed AD and the Service Bulletin

   What are the Commenters' Concerns? Two commenters note a difference between the service bulletin and the proposed AD, regarding the dye penetrant inspection procedure. One of these commenters also points out that ASTM E1417-95 was referred to as ASTM E1417-99 in the NPRM.

   What is FAA's Response to the Concerns? We concur that there is a difference between the dye penetrant inspection procedure proposed in the NPRM and that contained in the original service bulletin. When the AD and service bulletin differ, the AD takes precedence. In addition, FAA received a revision to the ASTM document (E1417-99 from E1417-95) after preparing the NPRM.

   However, as discussed previously, FAA is not requiring the dye penetrant inspection. Comment Issue No. 7: Do Not Include the Reporting Requirement

   What is the Commenters' Concern? Seven commenters recommend that FAA not require the reporting requirement for the dye penetrant inspection. These commenters state that this proposed requirement is irrelevant to the safety of the aircraft.

   What is FAA's Response to the Concern? We concur. As discussed previously, FAA is not including this inspection in the AD, so there is no need for the reporting requirement.

   We are not including the reporting requirement in the AD. Comment Issue No. 8: Inspect the Spar Caps and Doublers for Corrosion Any Time a Wing Is Removed

   What are the Commenters' Concerns? Six commenters request that FAA require inspection of the of spar caps and doublers for corrosion any time a wing is removed. The commenters recommend this inspection from the roof rib to the first rib outboard or to the inboard fuel tank.

   What is FAA's Response to the Concerns? We do not concur. We have not received any record of wing corrosion on the affected airplanes. The actions in this AD address the unsafe condition.

   We are not changing the AD as result of these comments. Comment Issue No. 9: Redesign the Wing Attachment

   What are the Commenters' Concerns? One commenter recommends a redesign of the wing attachment area to correct the unsafe condition. Another commenter suggests that the manufacturer conduct a test of the wing/fuselage attachment area.

   What is FAA's Response to the Concerns? We have determined that incorporating the doubler kit restores the wing spars of the affected airplanes to their required strength and addressses the unsafe condition referenced in this AD. We will evaluate any data pertaining to a redesign of the wing attachment area or other alternative method of compliance, as long as it is submitted in accordance with the procedures included in this AD.

   We are not changing the AD as a result of these comments. Comment Issue No. 10: The FAA Underestimated the Cost Impact

   What are the Commenters' Concerns? Two commenters state that FAA underestimated the costs of implementing the actions proposed in the NPRM. Another commenter states that the cost impact analysis is inadequate because it is designed to address transport category airplanes and not general aviation aircraft. This commenter suggests that the costs of accomplishing this AD could exceed $5,000 per airplane.

   What is FAA's Response to the Concerns? We do not concur that the cost analysis is inadequate. The cost impact as proposed in the NPRM is $4,920 per airplane ($2,400 for the inspections and $2,520 for the modification). However, we are not requiring wing removal and a dye penetrant inspection in the AD. We are now only requiring a visual inspection of the wing spar doublers (with replacement if found cracked) and modification. This reduces the time and cost necessary to accomplish the inspection from approximately 40 workhours per airplane to approximately 1 workhour per airplane. Comment Issue No. 11: Withdraw the AD

   What is the Commenter's Concern? One commenter requests that FAA withdraw the NPRM because the service bulletin is effective.

   What is FAA's Response to the Concern? We do not concur. The only way we can assure that all affected airplane owners/operators accomplish the actions in a service bulletin is through the issuance of an AD.

   We are not changing the AD as a result of these comments. Comment Issue No. 12: Change the Compliance Time

   What are the Commenters' Concerns? Several commenters request an extension to the compliance time. The commenters state that the available repair/maintenance facilities could not accomplish the work on all affected airplanes within the proposed compliance time.

   One commenter recommends requiring repetitive inspections of the bolt holes and only requiring the doubler kit if cracks are found during an inspection.

   Two commenters request a reduction in the compliance time to 25 hours time-in-service (TIS) to coincide with the service bulletin. This commenter refers to an incident where the wing spar was cracked on an affected airplane with less than 300 hours TIS.

   What is FAA's Response to the Concerns? Since issuance of the NPRM, we have received information regarding wing spar cracks on an airplane with 270 hours TIS. We also have additional reports of wing spar cracking on airplanes with 556 hours TIS and 538 hours TIS.

   Based on this information, we do not concur with the request to extend the compliance time. We are reducing the compliance time although not to coincide with the service bulletin. We have determined that the wing spars on all of the affected airplanes should be inspected within 50 hours TIS or 12 months after the effective date of the AD (whichever occur first), regardless of the total number of hours currently accumulated on the wing spar. The NPRM proposed to allow low time airplanes to reach 500 hours total TIS on the wing spar before requiring inspection and modification. Because the latest reports show that cracking could occur prior to 300 hours TIS, we have determined that the 50-hour TIS or 12-month compliance time will eliminate the unsafe condition presented in this AD without inadvertently grounding any of the affected airplanes.

   We do not concur with allowing repetitive inspections instead of mandatory modification. Constant removal of the bolts could cause unnecessary damage. The FAA's policy is to require a modification when incorporation of that modification could eliminate or reduce the number of required inspections.

   The FAA's Determination and Followup Action

   What Have We Decided?

   After careful review of all available information related to the subject presented above, including the above-referenced comments, FAA has determined that:

   [[Page 34068]]

   --The changes to the proposed AD as described in the above comment disposition should be incorporated; and --AD action should be taken to incorporate these changes to detect and correct cracks in the wing spar doublers, which could result in the wing separating from the airplane with consequent loss of control.

   What Is Our Next Action?

   Since the change in the compliance time increases the burden on the owners/operators of the affected airplanes over what was proposed in the NPRM, we are required to allow the public additional time to comment on the AD.

   Because additional reports show the cracks are occurring in the wing spar doublers on the affected airplanes with less hours TIS than initially expected, FAA finds that notice and opportunity for public prior comment are impracticable. Therefore, good cause exists for making this amendment effective in less than 30 days.

   What Does This AD Require?

   This AD requires you to accomplish the following:

   --Inspect the left and right wing upper and lower spar doublers for cracks; --Replace any cracked parts; and --Incorporate a modification kit.

   What Procedures Must You Use To Accomplish This AD?

   You must use the procedures in Revo, Inc. Service Bulletin B-79 R1--Revised January 5, 2000, to accomplish this AD.

   What Is the Compliance Time of This AD?

   At whichever of the following that occurs first:

   --Within the next 50 hours time-in-service (TIS) after June 20, 2000 (the effective date of this AD); or --On or before June 20, 2001 (12 months after the effective date of this AD).

   Why Is the Compliance in Both Hours TIS and Calendar Time?

   The fatigue cracks on the wing spar doublers of affected airplanes may have already initiated and could be further developing on the low- usage airplanes as well as high-usage airplanes. Utilizing the dual compliance times would assure that cracks in the wing spars are detected on all affected airplanes in a timely manner without inadvertently grounding any of the affected airplanes.

   Comments Invited

   This action is in the form of a final rule and the FAA did precede it with notice and opportunity for public comment. However, the change in compliance time, as described above, has changed because of information received since the notice. FAA is issuing the information in this final rule without prior notice because an urgent situation concerning safety of flight exists. However, FAA is still inviting comments on this 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. The FAA will consider all comments received on or before the closing date. We may amend this rule in light of comments received. Factual information that supports your ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether we need to take additional rulemaking action.

   The FAA is re-examining 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 whether the style of this document is clearer, 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.plainlanguage.gov.

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

   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-27-AD.'' We will date stamp and mail the postcard back to you.

   Regulatory Impact

   These regulations will 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. Therefore, FAA has determined that this final rule does not have federalism implications under Executive Order 13132.

   The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and is not a significant regulatory action under Executive Order 12866. We have determined that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If FAA determines that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, we will prepare a final regulatory evaluation. You may obtain a copy of the evaluation (if required) from the Rules Docket.

   List of Subjects in 14 CFR Part 39

   Air transportation, Aircraft, Aviation safety, Incorporation by Reference, Safety.

   Adoption of the Amendment

   Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (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.

   Sec. 39.13 [Amended]

2. FAA amends Sec. 39.13 by adding a new airworthiness directive (AD) to read as follows:

   2000-10-22 Revo, Incorporated: Amendment 39-11746; Docket No. 99- CE-27-AD.

   (a) What airplanes are affected by this AD? This AD applies to the following model and serial number airplanes, certificated in any category; that incorporate any of the wing spar part numbers (or FAA-approved equivalent part numbers) that are specified below the airplane models and serial numbers:

   Affected Airplanes

   Model

   Serial Nos.

   Lake LA 4................................. 246 through 421, 423 through 429, 445, and 446. Lake LA-4A................................ 244 and 245. Lake LA-4P................................ 121. Lake LA-4 200............................. 422, 430 through 444, and all serial numbers after 446. Lake Model 250............................ 1 through 232.

   [[Page 34069]]

   Wing Spar Part Numbers Incorporated

   Wing spar parts

   Part Nos.

   Upper Spar Cap Angles..................... 2-1610-015 and 2-1610-016. Lower Spar Cap Angles..................... 2-1610-075 and 2-1610-076. Upper Spar Doublers....................... 2-1610-061 and 2-1610-081 and 2-1610-065. Lower Spar Doublers....................... 2-1610-063 and 2-1610-083.

   (b) Who must comply with this AD? This AD applies to anyone who wishes to operate any of the above airplanes on the U.S. Register .

   (c) What problem does this AD address? The actions of this AD are intended to detect and correct cracks in the wing spars, which could result in loss of the wing with consequent loss of control of the airplane.

   (d) What actions must I accomplish to address this problem? To address this problem, you must accomplish the following:

   Action

   When

   Procedures

   (1) Inspect the left and right At whichever of In accordance with wing upper and lower spar

   the following the Inspection doublers for cracks.

   that occurs

   section of Revo, first:.

   Inc. Service (i) Within the Bulletin B-79 R1-- next 50 hours Revised January time-in-service 5, 2000. (TIS) after June 20, 2000 (the effective date of this AD); or. (ii) On or before June 20, 2001 (12 months after the effective date of this AD). (2) Replace any cracked wing Prior to further In accordance with spar doubler with a new part flight after the the applicable that incorporates the same part required

   maintenance number (or FAA-approved

   inspection.

   manual. equivalent part number). (3) Incorporate Modification Kit Prior to further In accordance with B-79.

   flight after the the Kit required

   Installation inspection.

   section of Revo, Inc. Service Bulletin B-79 R1-- Revised January 5, 2000.

   (e) What if I need to replace a wing on my airplane? After the effective date of this AD, you may not install a wing on any of the affected airplanes, unless one of the following exists:

   (1) The wing is new from the factory; or

   (2) The inspection, applicable replacement, and kit incorporation requirements of this AD have been accomplished at the time of installation.

   (f) Can I comply with this AD in any other way? You may use an alternative method of compliance or adjust the compliance time if:

   (1) Your alternative method of compliance provides an equivalent level of safety; and

   (2) The Manager, Boston Aircraft Certification Office (ACO), approves your alternative. Submit your request through an FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Boston ACO.

   Note: This AD applies to each airplane identified in paragraph (a) of this AD, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/ operator must request approval for an alternative method of compliance in accordance with paragraph (f) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if you have not eliminated the unsafe condition, specific actions you propose to address it.

   (g) Where can I get information about any already-approved alternative methods of compliance? Contact Mr. Richard B. Noll, Aerospace Engineer, FAA, Boston Aircraft Certification Office, 12 New England Executive Park, Burlington, Massachusetts 01803; telephone: (781) 238-7160; facsimile: (781) 238-7199.

   (h) What if I need to fly the airplane to another location to comply with this AD? The FAA can issue a special flight permit under sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate your airplane to a location where you can accomplish the requirements of this AD.

   (i) Are any service bulletins incorporated into this AD by reference? Actions required by this AD must be done in accordance Revo, Inc. Service Bulletin B-79 R1--Revised January 5, 2000. The Director of the Federal Register approved this incorporation by reference under 5 U.S.C. 552(a) and 1 CFR part 51. You can get copies from REVO, Incorporated, P.O. Box 312, One High Street, Sanford, Maine 04073. You can look at copies at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri; or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC.

   (j) When does this amendment become effective? This amendment becomes effective on June 20, 2000.

   Issued in Kansas City, Missouri, on May 17, 2000. Michael Gallagher, Manager, Small Airplane Directorate, Aircraft Certification Service.

   [FR Doc. 00-13084Filed5-25-00; 8:45 am]

   BILLING CODE 4910-13-U