Airworthiness Directive · Amendment 39-13893 · Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SP, and 747SR Series Airplanes
Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SP, and 747SR Series Airplanes
Superseded. A later AD replaced this one: AD 2007-01-15. Comply with the one in force.
This AD applies to Boeing 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SP, and 747SR series airplanes; as listed in Boeing Alert Service Bulletin (ASB) 747-54A2224, dated September 30, 2004; certificated in any category.
The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747- 200C, 747-200F, 747-300, 747SP, and 747SR series airplanes. This AD requires repetitive inspections to detect cracks and fractures of the strut front spar chord assembly at each strut location, and repair if necessary. This AD is prompted by a report of a fractured front spar chord assembly for strut No. 3, which resulted in the loss of the strut upper link load path. We are issuing this AD to prevent loss of the strut upper link load path and consequent fracture of the diagonal brace, which could result in in-flight separation of the strut and engine from the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
Within 90 days after the effective date of this AD, perform detailed and HFEC inspections to detect any cracks or fractures of the front spar chord assembly for struts Number 1 through 4 inclusive, in accordance with Boeing ASB 747-54A2224, dated September 30, 2004.
(f) Accomplishment of the detailed and HFEC inspections in accordance with Boeing 747 Fleet Team Digest 747-FTD-54-04002, dated April 15, 2004, May 4, 2004, June 1, 2004, July 12, 2004, or July 28, 2004; or Boeing Message 1-C6ELC (Service Request ID No.: 218724992), dated April 14, 2004; before the effective date of this AD, is considered acceptable for compliance with the requirements of paragraph (e) of this AD.
For airplanes on which no crack or fracture is detected: At the times specified in Table 1—Repetitive Intervals of this AD, perform the detailed and HFEC inspections required by paragraph (e) of this AD at the intervals specified in Table 1.
| For Airplanes identified in Boeing ASB 747-54A2224, dated September 30, 2004, as— | At intervals not to exceed— |
|---|---|
| Group 1 | 1,000 flight cycles or 18 months, whichever occurs first. |
| Group 2 and Group 3 | 1,200 flight cycles or 18 months, whichever occurs first. |
| Group 4 and Group 6 | 1,500 flight cycles or 18 months, whichever occurs first. |
| Group 5 | 2,000 flight cycles or 18 months, whichever occurs first. |
If any crack or fracture is found during any inspection required by this AD, and the bulletin specifies contacting Boeing for appropriate action: Before further flight, repair the crack or fracture according to a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or per data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative (DER) who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the approval must specifically reference this AD.
