Federal Aviation Administration

The FAA received recent reports of cracks found in the wings of two RAC 1900D airplanes. During routine maintenance, the wing rear spar lower caps and rear spar web were found to have significant cracks.

The RAC Structural Inspection Manual requires a thorough inspection of the wing rear spar at 17,500 hours time-in-service (TIS) with repetitive inspections at intervals of 3,000 hours TIS.

One airplane had 19,126 hours TIS when cracks were found. The cracks were in the lower aft spar cap flange, but the cracks extended upward into the web and terminated at the lightening hole in the spar web. Fasteners were also found missing in the spar cap and wing cove splice plate. There were no discrepancies recorded from the initial inspection at 17,500 hours TIS on this airplane.

Early indications show similar cracking on the other airplane. We continue to gather information on this airplane.

Analysis shows that similar cracks could also develop in the wings of the Models 1900 and 1900C airplanes.

FAA’s Determination

After careful review of all available information related to the subject presented above, we have identified an unsafe condition that is likely to exist or develop on other products of this same type design. For this reason, the FAA has determined that AD action should be taken to detect and correct cracking in the wing rear spar lower caps of the affected airplanes before the cracks grow to failure. Such a wing failure could result in the wing separating from the airplane with consequent loss of control.

AD Requirements

This AD requires the following:

• A one-time visual inspection of both the left and right wing rear spar lower caps for cracking and other damage such as loose or missing fasteners.
• Repair of any cracks or damage found.
• Report of any cracks or damage found to the FAA and RAC.

Compliance

(e) To address this problem, you must do the following:

Actions	Compliance	Procedures
(1) A one-time visual inspection of both the left and right wing rear spar lower caps for cracks and other damage such as loose or missing fasteners.	At whichever occurs later after receipt of this emergency AD: (i) Within 24 hours; or (ii) Prior to further flight.	Follow the procedures in the Appendix to this AD.
(2) For the inspection in paragraph (e)(1) of this AD, you may return/position the airplane to a home base, hangar, maintenance facility, etc.	For this repositioning, you may operate the airplane up to 3 hours time-in-service provided the flight(s) occur(s) no later than 30 days after receipt of this emergency AD.	The following limitations are imposed for such a repositioning flight: (i) ONLY THE PILOT AND ANY ADDITIONAL FLIGHT CREW MEMBER REQUIRED FOR SAFE OPERATION IS ALLOWED FOR THIS FLIGHT; (ii) FLIGHT INTO KNOWN OR FORECAST MODERATE OR SEVERE TURBULENCE IS PROHIBITED; and (iii) INDICATED AIRSPEED IS LIMITED TO 175 KNOTS MAXIMUM.
(3) Repair any cracks or other damage such as loose or missing fasteners found during the inspection required in paragraph (e)(1) of this AD. Do this by obtaining and incorporating an FAA-approved repair scheme from RAC.	Before further flight after the inspection required by paragraph (e)(1) of this AD.	Contact RAC at Post Office Box 85, Wichita, Kansas 67201-0085; phone: 316-676-8366; fax: (316) 676-8745; email: tom_peay@rac.ray.com.
(4) Report the inspection results to the FAA and RAC. For the reporting requirement in this AD, under the provisions of the Paperwork Reduction Act, the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120-0056.	Within 72 hours after completing the inspection required in paragraph (e)(1) of this AD.	Send your report to Steven E. Potter, FAA, 1801 Airport Road, Wichita, Kansas 67209; fax: (316) 946-4107; email: steven.potter@faa.gov; and Tom Peay, Raytheon Aircraft Company, Post Office Box 85, Wichita, Kansas 67201-0085; fax: (316) 676-8745; email: tom_peay@rac.ray.com. Include in your report the following information: (i) aircraft model and serial number; (ii) number of cycles; (iii) aircraft hours TIS; (iv) left and right wing lower spar cap hours TIS; (v) hours TIS on the spar cap since last inspection; (vi) answer yes or no whether cracking, missing fasteners, or other damage was found; and (vii) if cracking was found, identify size and location of cracks

Alternative Methods of Compliance

(h) The Manager, Wichita Aircraft Certification Office, FAA, ATTN: Steven E. Potter, FAA, 1801 Airport Road, Wichita, Kansas 67209; telephone: (316) 946-4124; fax: (316) 946-4107, has the authority to approve AMOCs for this AD, if requested using the procedures in 14 CFR 39.