Proposed AD for all Piper PA-28 Series aircraft and the PA-32 (AD 2018-CE-049-AD) which either: 1. Has accumulated 5,000 or more hours; 2. Has had either main wing spar replaced with a serviceable part (used with time already on the part); or 3. Has missing and/or incomplete maintenance records. The FAA estimates that this AD will affect 19,696 aircraft on the U.S. Register.
This AD is prompted by the loss of a 7,690 TT PA28R-201 Arrow which experienced the loss of a wing only 28 hours since its Annual Inspection, and then the subsequent discovery of fatigue cracks in the visually inaccessible area of the lower main wing spar cap (both left and right.)
In accordance with the draft instructions of this proposed AD, there are two steps that must be undertaken within 30 days after the issuance of this AD, and before further flight:
- Review all airframe records for any main wing spar replacements, as well as counting the number of 100-hour inspections completed on the aircraft since new
- Calculate the ‘factored’ service hours for each main wing spar
If the records review listed in step 1 cannot be satisfactorily completed, or one, or both spars have been previously replaced with serviceable units (not new), or the ‘factored’ hours listed in step 2 result in 5,000 hours or more, then the lower main wing spar bolt holes (both LH/RH wings) must be inspected for cracks by the NDT method of Eddy Current Inspection performed by an NAS 410 Level 2, or Level 3 certified technician. The accept/reject criteria require that any crack, or crack-like indication observed on the scope, with an amplitude to or greater than 50 percent of the reference level signal (≧0.015”) must be rejected and documented.
If either of the Wing Spar Caps fail the Eddy Current Inspection, then the affected Spar must be replaced with a new unit (not used.)
Records Review and Factored Arithmetic, estimated to be $200
Eddy Current Inspection, estimated to be $600
Spar Replacement (one unit, not both), estimated to be $8,500 (both = $17,000)