AD 96-12-20

This amendment supersedes an existing airworthiness directive (AD), applicable to certain Lockheed Model 382, 382B, 382E, 382F, and 382G series airplanes, that currently requires visual inspections to detect loose, missing, or deformed fasteners in the upper truss mounts of certain engines, inspections to detect cracking in the associated tangs, and replacement of damaged parts. This amendment adds a requirement for repetitive ultrasonic inspections to detect cracking of the upper tangs and replacement of cracked parts. This amendment also provides for an optional terminating action for the repetitive inspections, and revises the applicability of the rule to specify groupings of airplanes. This amendment is prompted by reports indicating that fatigue cracking of the tangs of the upper truss mount has been detected. The actions specified by this AD are intended to prevent multiple failures of the upper truss mounts due to problems associated with fatigue cracking, which could adversely affect the integrity of the engine mount structure.

The incorporation by reference of Hercules Service Bulletin 382-71-20, dated March 18, 1994, as listed in the regulations, is approved by the Director of the Federal Register as of July 15, 1996.

The incorporation by reference of Lockheed Alert Service Bulletin A382-71-19/A82-687, dated December 23, 1993, as listed in the regulations, was approved previously by the Director of the Federal Register as of February 18, 1994 (59 FR 5078, February 3, 1994).

Final Rule

96-12-20 LOCKHEED AERONAUTICAL SYSTEMS COMPANY: Amendment 39-9663. Docket 95-NM-10-AD. Supersedes AD 94-03-03, Amendment 39-8809.

Applicability: Model 382, 382B, 382E, 382F, and 382G series airplanes having serial numbers 3946 through 4512 inclusive, on which the outer wings have been replaced in accordance with Manufacturing End Product (MEP) 12R/13R or MEP 9T/10T; and Model 382E and Model 382G serial airplanes having serial numbers 4561 through 5225 inclusive; certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise 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, or repair 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: Required as indicated, unless accomplished previously.

To prevent multiple failures of the upper truss mounts, which could adversely affect the integrity of the engine mount structure, accomplish the following:

(a) Prior to the accumulation of 15,000 total hours time-in-service since wing replacement (for Model 382, 382B, 382E, and 382F series airplanes on which the outer wings have been replaced in accordance with MEP 12R/13R or MEP 9T/10T); or prior to the accumulation of 15,000 total hours time-in-service (for Model 382G series airplanes); or within 30 days after February 18, 1994 (the effective date of AD 94-03-03, amendment 39-8809), whichever occurs later: Accomplish the requirements of paragraphs (a)(1) and (a)(2) of this AD. Repeat the specified inspections thereafter at intervals not to exceed 300 hours time-in-service or 100 landings, whichever occurs later, until the requirements of paragraph (b) of this AD are accomplished.

(1) Perform a general visual inspection to detect loose, missing, or deformed fasteners on the inboard and outboard upper truss mounts of the No. 1 and No. 4 (left and right outboard) engines, in accordance with Lockheed Alert Service Bulletin A382-71-19/A82-687, dated December 23, 1993. If any loose, missing, or deformed fastener is found, prior to further flight, replace it in accordance with Hercules Structural Repair Manual (SRM), Document Number SMP 583.

(2) Perform a general visual inspection to detect cracking of the truss mount upper tangs of the No. 1 and No. 4 engine truss mounts in accordance with Lockheed Alert Service Bulletin A382-71-19/A82-687, dated December 23, 1993. If cracking is detected in any truss mount upper tang, prior to further flight, replace it with a new engine truss mount in accordance with Hercules SRM, Document Number SMP 583, or in accordance with a method approved by the Manager, Atlanta Aircraft Certification Office (ACO), FAA, Small Airplane Directorate.

(b) Perform an ultrasonic inspection to detect cracking of the upper tangs of the No. 1 outboard and the No. 4 inboard engine truss mounts, in accordance with Hercules Service Bulletin 382-71-20, dated March 18, 1994, at the time specified in paragraph (b)(1) or (b)(2) of this AD, as applicable. Accomplishment of this inspection terminates the inspections required by paragraph (a) of this AD.

(1) For Model 382, 382B, 382E, 382F, and 382G series airplanes on which the outer wings have been replaced in accordance with MEP 12R/13R or MEP 9T/10T: Accomplish the inspection at the earlier of the times specified in paragraphs (b)(1)(i) and (b)(1)(ii) of this AD.

(i) Prior to the accumulation of 15,000 total hours time-in-service since replacement of the outer wings, or within 90 days after the effective date of this AD, whichever occurs later. Or

(ii) Within 300 hours time-in-service or 100 landings, whichever occurs later, following the immediately preceding visual inspection accomplished in accordance with paragraph (a) of this AD.

(2) For Model 382E and 382G series airplanes having serial number 4561 through 5225 inclusive, other than those identified in paragraph (b)(1) of this AD: Accomplish the inspection at the earlier of the times specified in paragraphs (b)(2)(i) and (b)(2)(ii) of this AD.

(i) Prior to the accumulation of 15,000 total hours time-in-service, or within 90 days after the effective date of this AD, whichever occurs later. Or

(ii) Within 300 hours time-in-service or 100 landings, whichever occurs later, following the immediately preceding visual inspection accomplished in accordance with paragraph (a) of this AD.

(c) If no cracking is detected during the inspection required by paragraph (b) of this AD, repeat the inspection thereafter at intervals not to exceed 5,200 hours time-in-service.

(d) If any cracking is detected during the inspection required by paragraph (b) of this AD: Prior to further flight, accomplish the requirements of either paragraph (d)(1) or (d)(2) of this AD.

(1) Replace the truss mount assembly with a new assembly having part number 360013-15, -19, or -23 (for the outboard truss mounts of the No. 1 engine), or part number 360017-15, -19, or -23 (for the inboard truss mounts of the No. 4 engine), as applicable, in accordance with Hercules Structural Repair Manual (SRM), Document Number SMP 583. Prior to the accumulation of 15,000 hours time-in-service after installation of the engine truss mount assembly, perform an ultrasonic inspection as specified in paragraph (b) of this AD. Repeat that inspection thereafter at intervals not to exceed 5,200 hours time-in-service. Or

(2) Replace the truss mount assembly with part number 360013-31 or subsequent (for the truss mounts in the No. 1 engine), or part number 360017-31 or subsequent (for the inboard truss mounts of the No. 4 engine), as applicable, in accordance with SMP 583. Such replacement constitutes terminating action for the requirements of this AD.

(e) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Atlanta ACO. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Atlanta ACO.

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

(f) 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 theairplane to a location where the requirements of this AD can be accomplished.

(g) The ultrasonic inspection shall be done in accordance with Hercules Service Bulletin 382-71-20, dated March 18, 1994. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. The general visual inspections shall be done in accordance with Lockheed Alert Service Bulletin A382- 71-19/A82-687, dated December 23, 1993. The incorporation by reference of this document was approved previously by the Director of the Federal Register, in accordance with 5 U.S.C. 552(a) and 1 CFR part 51, as of February 18, 1994 (59 FR 5078, February 3, 1994). Copies may be obtained from Lockheed Aeronautical Systems Support Company, Field Support Department, Dept. 693, Zone 0755, 2251 Lake Park Drive, Smyrna, Georgia 30080. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Small Airplane Directorate, Atlanta Aircraft Certification Office, Campus Building, Suite 2-160, 1701 Columbia Avenue, College Park, Georgia; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(h) This amendment becomes effective on July 15, 1996.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 94-03-03, amendment 39-8809 (59 FR 5078, February 3, 1994), which is applicable to certain Lockheed Model 382, 382B, 382E, 382F, and 382G series airplanes, was published in the Federal Register on May 16, 1995 (60 FR 26005). That action proposed to supersede AD 94-03-03 to continue to require visual inspections to detect loose, missing, or deformed fasteners in the upper truss mounts of certain engines, inspections to detect cracking in the associated tangs, and replacement of damaged parts with new parts. The action also proposed to add a requirement for repetitive ultrasonic inspections to detect cracking of the upper tangs and replacement of cracked parts with certain new or serviceable parts. That action also proposed to provide for an optional terminating action for the repetitive inspections. Additionally, that action proposed to revise the applicability of the existing rule to specify appropriate groupings of airplanes subject to the rule.

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received from the sole commenter.

Request to Revise Replacement Requirements for Cracked Upper Tang
The commenter, the manufacturer, requests that paragraph (a)(2) of the proposed rule be revised to change the replacement requirements for the upper tang to specify that, if cracking is found, the operator must replace the truss mount, not the upper tang. The commenter notes that the upper tang is an integral part of the truss mount and it cannot be replaced unless the truss mount itself is replaced.

The FAA concurs. The manufacturer has confirmed that it is impossible to replace the upper tang without replacing the truss mount. From this, the FAA assumes that operators complying with AD 94-03-03 (which contained the requirement to replace the upper tang) would have replaced the truss mount, and not just the upper tang, if replacement was necessary in accordance with paragraph (a)(2) of that AD. In consideration of these factors, the FAA has revised paragraph (a)(2) of this final rule to clarify that the truss mount must be replaced if cracking is found in the upper tang.

Request to Prohibit Installation of Previously Used Truss Mounts
The commenter further requests that references to replacement with a "serviceable" truss mount assembly be deleted from the proposal. The commenter states that previously-used truss mounts would have existing fastener holes and, therefore, could not be used as a replacement part, since they would not be able to be installed physically on the airplane.

The FAA concurs. Since a previously-used truss mount cannot be installed on an airplane because of the existing fastener holes, the FAA has deleted this language from paragraphs (a) and (d) of the final rule.

Request toRevise Reference to Structural Repair Manual
The commenter also requests that paragraphs (d)(1) and (d)(2) of the proposed rule, which require replacement of the truss mount assembly, be revised to refer to the Structural Repair Manual, "Document SMP . . .," rather than "Document SRM . . ." The commenter states that instructions for replacing the truss mounts are described in Document SMP.

The FAA acknowledges that the commenter is correct, and has revised this reference in this final rule. Additionally, the FAA has corrected the number of that particular document to read "SMP 583"

Request to Delete Prohibition of Future Installation of Certain Truss Mounts
The commenter requests that paragraph (e) of the proposed rule be deleted. That paragraph would prohibit the installation of certain part-numbered outboard and inboard engine truss mounts on any airplane unless the truss mount had been inspected in accordance with the SRM. That paragraph is meant to preclude the possibility of a those truss mounts being entered into service without having the necessary inspection performed. However, the commenter points out three considerations to support its request to delete the proposed requirement:

1. First, the intent of the inspection required by the AD is to detect fatigue damage that is associated with the fastener holes in the truss mounts.

2. Second, a truss mount does not have fastener holes in it until it is installed on the airplane; therefore, a new truss mount would not need to be inspected for fatigue damage, since it would not have accumulated enough time for the such damage to occur.

3. Third, if the final rule does not permit the installation of used ("serviceable") truss mounts, then only new truss mounts -- on which fatigue would not be a problem -- would be permitted to be installed.

For the reasons specified by the commenter, and in light of the previously discussed changes made to this final rule, the FAA concurs that proposed paragraph (e) is unnecessary. The FAA has deleted it from the final rule.

Conclusion
After careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule with the changes previously described. The FAA has determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

Cost Impact
There are approximately 112 Lockheed Model 382, 382B, 382E, 382F, and 382G series airplanes of the affected design in the worldwide fleet. The FAA estimates that 18 airplanes of U.S. registry will be affected by this AD.

Accomplishment of the visual inspections that were required by AD 94-03-03 and retained in this AD, take approximately 10 work hours per airplane, at an average labor rate of $60 per work hour. Based on these figures, the total cost impact of those inspections on U.S. operators is estimated to be $10,800, or$600 per airplane, per inspection cycle.

Accomplishment of the ultrasonic inspections that are added by this new AD will take approximately 6 work hours per airplane, at an average labor rate of $60 per work hour. Based on these figures, the total cost impact of the these inspections on U.S. operators is estimated to be $6,480, or $360 per airplane, per inspection cycle.

The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. However, it is reasonable to assume that operators currently subject to the requirements of AD 94-03-03 have already implemented the repetitive visual inspections required by that AD.

Should an operator elect to accomplish the optional terminating action that is provided by this AD action, it would take approximately 60 work hours per airplane to accomplish it, at anaverage labor rate of $60 per work hour. The cost of required parts would be approximately $17,000 per airplane. Based on these figures, the cost impact of the optional terminating action would be $20,600 per airplane.

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.

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) 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. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES."

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 amendment 39-8809 (59 FR 5078, February 3, 1994), and by adding a new airworthiness directive (AD), amendment 39-9663, to read as follows: