AD 98-15-18 Airworthiness Directives; Maule Aerospace Technology, Inc. Airplanes

Makes named: maule. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to the following Maule Aerospace Technology, Inc. airplanes, all serial numbers, identified in figure 1 of paragraph (c) of this AD, that are: (1) Equipped with original equipment manufacturer (OEM) Maule Aerospace Technology, Inc. rear wing lift struts, part number (P/N) 2079E (or FAA-approved equivalent part numbers), and/or front wing lift struts, P/N 2080E (or FAA-approved equivalent part numbers), excluding airplanes equipped with four Maule sealed lift struts, P/N 2200E and P/N 2201E, which are identified by two raised weld spots on the upper end of the strut just below the serial number plate. Removal of the upper cuff is needed to locate the weld spots; and (2) certificated in any category. Figure 1 to Paragraph (c) of This AD—Applicability           Models Bee Dee M-4 M-4 M-4C M-4S M-4T M-4-180C M-4-180S M-4-180T M-4-210 M-4-210C M-4-210S M-4-210T M-4-220 M-4-220C M-4-220S M-4-220T M-5-180C M-5-200 M-5-210C M-5-210TC M-5-220C M-5-235C M-6-180 M-6-235 M-7-235 M-7-235A M-7-235B M-7-235C MT-7-235 MX-7-160 MX-7-180 MX-7-180A MX-7-180B MX-7-235 MX-7-420 MXT-7-160 MXT-7-180 MXT-7-180A M-8-235

Since AD 98-15-18, Amendment 39-10669 (63 FR 39018, July 21, 1998), was issued, the AD format has been revised, and certain paragraphs have been rearranged. As a result, the corresponding paragraph identifiers have changed in this AD, as listed in the following table: Table 1 to Paragraph (f) of This AD—Revised Paragraph Identifiers Requirement in AD 98-15-18 Corresponding requirement in this AD paragraph (a) paragraph (h) paragraph (a)(1) paragraph (i)(1) paragraph (a)(1)(i) paragraph (i)(1)(i) paragraph (a)(1)(ii) paragraph (i)(1)(ii) paragraph (a)(2) paragraph (i)(2) paragraph (a)(2)(i) paragraph (i)(2)(i) paragraph (a)(2)(ii) paragraph (i)(2)(ii) paragraph (a)(3) paragraph (j)(1) paragraph (a)(4) and (c) paragraph (j)(2) paragraph (b) Removed

Unless already done (compliance with AD 98-15-18, Amendment 39-10669 (63 FR 39018, July 21, 1998)), do the following actions within the compliance times specified in paragraphs (h) through (j) of this AD, including all subparagraphs. Properly unsealing and resealing a sealed wing lift strut is still considered a terminating action for the repetitive inspection requirements of this AD as long as all appropriate regulations and issues are considered, such as static strength, fatigue, material effects, immediate and long-term (internal and external) corrosion protection, resealing methods, etc. Current FAA regulations in 14 CFR 43.13(b) specify that maintenance performed will result in the part's condition to be at least equal to its original or properly altered condition. Any maintenance actions that unseal a sealed wing lift strut should be coordinated with the Atlanta Aircraft Certification Office (ACO) through the local airworthiness authority (e.g., Flight Standards District Office). There are provisions in paragraph (k) of this AD for approving such actions as an alternative method of compliance (AMOC).

(1) The subject of this AD was originally prompted by reports of corrosion damage found on the wing lift struts. We are revising AD 98-15-18, Amendment 39-10669 (63 FR 39018, July 21, 1998), because of reports that the language in paragraph (b) had been misinterpreted and caused confusion. Since we issued AD 98-15-18, we were informed by the manufacturer that Model MXT-7-420 airplanes are no longer in existence, are no longer type certificated, and should be removed from the Applicability section. This AD removes Model MXT-7-420 airplanes from the Applicability section and clarifies the intent of the language in paragraph (b) of AD 98-15-18, which is being removed by this AD. (2) This AD clarifies the FAA's intention that if a sealed wing lift strut assembly is installed as a replacement part, the repetitive inspection requirement is terminated only if the seal is never improperly broken. If the seal is improperly broken, then that wing lift strut becomes subject to continued repetitive inspections. We did not intend to promote drilling holes into or otherwise unsealing a sealed strut. This AD retains all the actions required in AD 98-15-18 and does not add any actions over that already required in AD 98-15-18. This AD does not add any additional burden to the owners/operators of the affected airplanes. (3) We are issuing this AD to detect and correct corrosion on the front and rear wing lift struts, which could cause the wing lift strut to fail. This failure could result in the wing separating from the airplane.

This AD revises AD 98-15-18, Amendment 39-10669 (63 FR 39018, July 21, 1998), which superseded AD 95-26-18, Amendment 39-9476 (61 FR 623, January 9, 1996.)