Airworthiness Directive · Amendment 39-14535 · McDonnell Douglas Model DC-9-10, DC-9-20, DC-9-30, DC-9-40, and DC-9-50 Series Airplanes
McDonnell Douglas Model DC-9-10, DC-9-20, DC-9-30, DC-9-40, and DC-9-50 Series Airplanes
This AD applies to McDonnell Douglas Model DC-9-11, DC-9-12, DC-9-13, DC-9-14, DC-9-15, DC-9-15F, DC-9-21, DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F, DC-9-33F, DC-9-34, DC-9-34F, DC-9-32F (C-9A, C-9B), DC-9-41, and DC-9-51 airplanes; certificated in any category; as identified in McDonnell Douglas DC-9 Service Bulletin 53-168, dated November 17, 1983.
The FAA is adopting a new airworthiness directive (AD) for certain McDonnell Douglas Model DC-9-10, DC-9-20, DC-9-30, DC-9-40, and DC-9-50 series airplanes. This AD requires repetitive inspections for stress corrosion cracks of the main fuselage frame, and corrective actions if necessary. This AD also provides an optional terminating action for the repetitive inspections. This AD results from several reports of cracking of the main fuselage frame. We are issuing this AD to detect and correct stress corrosion cracking of the main fuselage frame, which could result in extensive damage to adjacent structure and reduced structural integrity of 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.
The term “service bulletin,” as used in this AD, means the Accomplishment Instructions of McDonnell Douglas DC-9 Service Bulletin 53-168, dated November 17, 1983, including McDonnell Douglas Service Sketch 3529, dated August 23, 1983.
Prior to the accumulation of 15,000 total flight hours, or within 3,400 flight hours after the effective date of this AD, whichever occurs later: Do a detailed inspection, eddy current inspection, or ultrasonic inspection for stress corrosion cracks of the main fuselage frame in accordance with the service bulletin. Except as provided by paragraph (h) of this AD, repeat the inspection thereafter at intervals not to exceed 8,000 flight hours until the replacement in paragraph (i) of this AD is accomplished.
Note 1: For the purposes of this AD, a detailed inspection is: “An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirror, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate procedures may be required.”
If any crack is found during any inspection required by this AD, do the applicable action in paragraph (h)(1), (h)(2), or (h)(3) of this AD.
(1) If the crack is in the pocket area and the crack is within the crack limits specified in McDonnell Douglas Service Sketch 3529, dated August 23, 1983: Repeat the inspection specified in paragraph (g) of this AD at intervals not to exceed 3,400 flight hours until the action in paragraph (i) of this AD is accomplished.
(2) If the crack is in the pocket area and the crack exceeds the crack limits specified in McDonnell Douglas Service Sketch 3529, dated August 23, 1983, before further flight: Do the action in paragraph (i) of this AD.
(3) If the crack is in the web, before further flight: Do the action in paragraph (i) of this AD.
(i) Replacing the frame with a new or serviceable frame made of 7075-T73 aluminum material in accordance with the service bulletin terminates the repetitive inspection requirements of this AD for that frame only.
Although the service bulletin referenced in this AD specifies to submit certain information to the manufacturer, this AD does not include that requirement.
After the effective date of this AD, no person may install on any airplane a main fuselage frame made of 7075-T6 aluminum material.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
