AD 97-17-03

This amendment supersedes Airworthiness Directive (AD) 97-13-11, which currently requires inspecting the 1/4-inch and 5/16-inch bolt hole areas on the lower spar caps for fatigue cracking on Ayres S2R series airplanes, and replacing any lower spar cap if fatigue cracking is found. That AD resulted from an accident on an Ayres S2R series airplane where the wing separated from the airplane in flight. AD 97-13-11 incorrectly references the Ayres Model S2R-R1340 airplanes as Model S2R-1340R. This AD requires the same actions as AD 97-13-11, but corrects the designation of the Model S2R-R1340 airplanes. The actions specified by this AD are intended to detect fatigue cracking of the lower spar caps, which, if not corrected, could result in the wing separating from the airplane with consequent loss of control of the airplane.

The incorporation by reference of certain publications listed in the regulations was previously approved by the Director of the Federal Register as ofJuly 10, 1997 (62 FR 36978).

Comments for inclusion in the Rules Docket must be received on or before October 17, 1997.

Final rule; request for comments.

97-17-03 AYRES CORPORATION: Amendment 39-10105; Docket No. 97-CE-65-AD. Supersedes AD 97-13-11; Amendment 39-10071.

Applicability: Airplanes with the following model and serial number designations with or without a -DC suffix, certificated in any category:

Group 1 Airplanes

Model
Serial Numbers
S-2R
5000R through 5099R.
S2R-R1340
R1340-011, R1340-012, R1340-019, R1340-020, R1340-024, R1340-025, and R1340-027.
S2R-R1820
R1820-001 through 1820-035.
S2R-T34
6000R through 6049R, T34-001 through T34-143, T34-145, T34-147 through T34-167, T34-171, T34-180, and T34-181*.
S2R-T15
T15-001 through T15-033**.
S2R-T11
T11-001 through T11-005.
S2R-G1
G1-101 through G1-108.

* The serial numbers of the Model S2R-T34 airplanes could incorporate T34-xxx, T36-xxx, T41-xxx, or T42-xxx. This AD applies to all of these serial number designations as they are all Model S2R-T34 airplanes.

** The serial numbers of the Model S2R-T15 airplanes could incorporate T15-xx and T27-xx. This AD applies to both of these serial number designations as they are both Model S2R-T15 airplanes.

Group 2 Airplanes

Model
Serial Numbers
S2R-R1340
R1340-028 through R1340-035.
S2R-R1820
R1820-036.
S2R-T65
T65-001 through T65-017.
S2RHG-T65
T65-002 through T65-017.
S2R-T34
T-34-144, T34-146, T34-168, T34-169, T34-172 through T34-179, and T34-189 through 34-226*.
S2R-T45
T45-001 through T45-014.
S2R-G6
G6-101 through G6-146.
S2R-G10
G10-101 through G10-138.
S2R-G5
G5-101 through G5-105.

* The serial numbers of the Model S2R-T34 airplanes could incorporate T34-xxx, T36-xxx, T41-xxx, orT42-xxx. This AD applies to all of these serial number designations as they are all Model S2R-T34 airplanes.

Group 3 Airplanes*

Model
Serial Numbers
600 S2D
All serial numbers beginning with 600-1311D.
S-2R
1380R and 1416R through 4999R.
S2R-R1340
R1340-001 through R1340-010, R1340-013 through R1340-018, R1340-021 through R1340-023, and R1340-026.
S2R-R3S
R3S-001 through R3S-011.

* Any Group 3 airplane that has been modified with a hopper of a capacity over 400 gallons, a piston engine greater than 600 horsepower, or any gas turbine engine makes the airplane a Group 1 airplane for the purposes of this AD. The owner/operator must inspect the airplane at the Group 1 compliance time specified in the Compliance section of this AD.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, 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 (e) of this AD. The request should include an assessment of the effect of the modification, alteration, orrepair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Inspections required as indicated below and any necessary replacement required prior to further flight as indicated in the body of this AD, unless already accomplished in accordance with AD 97-13-11 (superseded by this AD):

- Group 1 Airplanes: Required upon the accumulation of 2,700 hours time-in-service (TIS) on each lower spar cap or prior to further flight after the effective date of this AD, whichever occurs later.

- Group 2 Airplanes: Required upon the accumulation of 4,300 hours TIS on each lower spar cap or prior to further flight after the effective date of this AD, whichever occurs later.

- Group 3 Airplanes: Required upon the accumulation of 9,000 hours TIS on each lower spar cap or prior to further flight after the effective date of this AD, whichever occurs later.

To detect fatigue cracking of the lower spar caps, which, if not corrected, could result in the wing separating from the airplane with consequent loss of control of the airplane, accomplish the following:

(a) Inspect, using magnetic particle procedures, the 1/4-inch and 5/16-inch bolt hole areas on each lower spar cap for fatigue cracking. Accomplishment of the inspection is in accordance with Ayres Service Bulletin No. SB-AG-39, dated September 17, 1996.

(1) The magnetic particle inspection must follow American Society for Testing Materials (ASTM) E1444-94A, using wet particles meeting the requirements of the Society for Automotive Engineers (SAE) AMS 3046.

(2) This inspection is to be accomplished by a Level 2 or Level 3 inspector certified using the guidelines established by the American Society for Nondestructive Testing or MIL-STD-410.

(b) If any cracking is found during the inspection required by this AD, prior to further flight, replace the affectedlower spar cap in accordance with the affected maintenance manual. Upon replacement, total hours TIS starts over for that particular lower spar cap. Use the compliance time specified in the Compliance section of this AD to determine when the inspection is required.

(c) If any cracking is found during the inspection required by this AD, submit a report of inspection findings to the Manager, Atlanta Aircraft Certification Office (ACO), Campus Building, 1701 Columbia Avenue, Suite 2-160, College Park, Georgia 30337-2748; facsimile (404) 305-7348; at the applicable time specified in paragraph (c)(1) or (c)(2) of this AD. The report must include a description of any cracking found, the airplane serial number, and the total number of flight hours on the lower spar cap found cracked. Information collection requirements contained in this regulation have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-0056.

(1) For airplanes on which the inspection is accomplished after the effective date of this AD: Submit the report within 10 days after performing the inspection required by paragraph (a) of this AD.

(2) For airplanes on which the inspection has been accomplished in accordance with AD 97-13-11 (superseded by this AD): Submit the report within 10 days after the effective date of this AD, unless already accomplished.

(d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location to accomplish the modification requirements of this AD provided the following is followed:

(1) The hopper is empty.

(2) Vne is reduced to 126 miles per hour (109 knots).

(3) Flight into known turbulence is prohibited.

(e) An alternative method of compliance or adjustment of the compliancetime that provides an equivalent level of safety may be approved by the Manager, Atlanta Aircraft Certification Office (ACO), Campus Building, 1701 Columbia Avenue, Suite 2-160, College Park, Georgia 30337-2748.

(1) The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Atlanta ACO.

(2) Alternative methods of compliance approved in accordance with AD 97-13-11 (superseded by this action) are considered approved as alternative methods of compliance with this AD.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Atlanta ACO.

(f) The inspection required by this AD shall be done in accordance with Ayres Service Bulletin No. SB-AG-39, dated September 17, 1996. This incorporation by reference was previously approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51 as of July 10, 1997 (62 FR 36978). Copies may be obtained from the Ayres Corporation, P.O. Box 3090, One Rockwell Avenue, Albany, Georgia 31706-3090. Copies may be inspected at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(g) This amendment (39-10105) supersedes AD 97-13-11, Amendment 39-10071.

(h) This amendment becomes effective on September 5, 1997.

Discussion
AD 97-13-11, Amendment 39-10071 (62 FR 36978, July 10, 1997), currently requires the following on Ayres S2R series airplanes: inspecting the 1/4-inch and 5/16-inch bolt hole areas on the lower spar caps for fatigue cracking, and replacing any lower spar cap if fatigue cracking is found. Accomplishment of the inspection is in accordance with Ayres Service Bulletin No. SB-AG-39, dated September 17, 1996. This inspection utilizes magnetic particle procedures and must follow American Society for Testing Materials (ASTM) E1444-94A, using wet particles meeting the requirements of the Society for Automotive Engineers (SAE) AMS 3046. This inspection is to be accomplished by a Level 2 or Level 3 inspector certified using the guidelines established by the American Society for Nondestructive Testing or MIL-STD-410.

That AD resulted from an accident on an Ayres S2R series airplane where the wing separated from the airplane in flight. Investigationof all resources available to the FAA shows nine occurrences of fatigue cracking in the lower spar caps of Ayres S2R airplanes, specifically emanating from the 1/4-inch and 5/16-inch bolt holes. Although the investigation of the above-referenced accident is not complete, the FAA believes that the cause can be attributed to fatigue cracks emanating from the 1/4-inch and 5/16-inch bolt holes in the left lower spar cap.

Data accumulated by the FAA indicates that the fatigue cracks on these Ayres S2R series airplanes become detectable at different times based upon the type of engines and design of the airplane. With this in mind, the FAA has categorized these airplanes into three groups:

- Group 1 airplanes have steel spar caps with aluminum webs. These airplanes are capable of carrying heavier loads and data indicates that inspections in the affected areas of the lower spar caps should begin upon the accumulation of 2,700 hours time-in-service (TIS);

- Group 2 airplaneshave steel spar caps with steel webs. Because of the steel webs as opposed to aluminum, data indicates that inspections in the affected areas of the lower spar caps should begin upon the accumulation of 4,300 hours TIS; and

- Group 3 airplanes, which are the ones manufactured first, have steel spars with aluminum webs and low horsepower radial engines, and thus do not have the ability to carry as much weight as airplanes in the other two groups. Data indicates that inspections in the affected areas of the lower spar caps should begin upon the accumulation of 9,000 hours TIS.

Manufacture of the affected airplanes began in 1965 with the airplanes incorporating the lower horsepower radial engines. Many of the airplane models referenced in this AD are still currently in production. These airplanes are used in agricultural operations and average 500 hours TIS annually. With this in mind, some of the earlier manufactured airplanes could have as many as 16,000 hours total TIS.Actions Since Issuance of the Previous Rule
Since issuance of AD 97-13-11, the FAA realizes that it inadvertently referenced Ayres Model S2R-R1340 airplanes as Model S2R-1340R airplanes. Although the FAA believes that most affected operators will realize the intent of this airplane model designation, a few may either choose not to comply because legally they are not required to or they may not realize that the intent was to include the Model S2R-R1340 airplanes in the Applicability of AD 97-13-11.

The FAA's Determination
After examining the circumstances and reviewing all available information related to the incidents described above, the FAA has determined that AD action should be taken in order to detect fatigue cracking of the lower spar caps, which, if not corrected, could result in the wing separating from the airplane with consequent loss of control of the airplane.

Explanation of the Provisions of This AD
Since an unsafe condition has been identified that is likely to exist or develop in other Ayres S2R airplanes of the same type design, this AD supersedes AD 97-13-11 with a new AD. This AD retains the requirements from AD 97-13-11 of inspecting the 1/4-inch and 5/16-inch bolt hole areas on the lower spar caps for fatigue cracking, and replacing any lower spar cap where fatigue cracking is found; and changes the designation of the Ayres Model S2R-1340R airplanes to Ayres Model S2R-R1340 airplanes. Accomplishment of the inspection continues to be in accordance with Ayres Service Bulletin No. SB-AG-39, dated September 17, 1996. This inspection utilizes magnetic particle procedures and must follow American Society for Testing Materials (ASTM) E1444-94A, using wet particles meeting the requirements of the Society for Automotive Engineers (SAE) AMS 3046. This inspection is to be accomplished by a Level 2 or Level 3 inspector certified using the guidelines established by the American Society for Nondestructive Testing or MIL-STD-410.

Determination of the Effective Date of the AD
Since a situation exists (possible wing separation from the airplane) that requires the immediate adoption of this regulation, it is found that notice and opportunity for public prior comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days.

Comments Invited
Although this action is in the form of a final rule that involves requirements affecting immediate flight safety and, thus, was not preceded by notice and opportunity to comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications should identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket No. 97-CE-65-AD." The postcard will be date stamped and returned to the commenter.

Regulatory Impact
The regulations adopted herein will not have substantial direct effects 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, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

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. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket (otherwise, an evaluation is not required). A copy of it, if filed, may be obtained 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, pursuant to 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 USC 106(g), 40113, 44701.

39.13 [Amended]
2. Section 39.13 is amended by removing AD 97-13-11, Amendment 39-10071 (62 FR 36978, July 10, 1997), and by adding a new airworthiness directive (AD) to read as follows: