The Federal Aviation Administration is instructing Raytheon Beech 1900 operators inspect the aircrafts' rear wing spars before flight after routine maintenance on two unidentified 1900Ds revealed "significant cracks."

The FAA's Airworthiness Directive stated:

"This AD is the result of extensive cracks found in the wing rear spar lower caps and rear spar web of two of the affected airplanes. One of the airplanes also had missing fasteners. We are issuing this AD to detect and correct cracking and other damage in the wing rear spar lower caps of the affected airplanes before the cracks or damage lead to failure. Such a wing failure could result in the wing separating from the airplane with consequent loss of control."

Flight Global adds:

In its instruction, the FAA says one of the 1900Ds inspected had cracks in the lower aft spar cap flange that extended upward into the web and terminating at the lightening hole in the spar web. This same aircraft, which was undergoing maintenance at 19,126h time-in-service, was also missing fasteners from the spar cap and wing cove splice plate.

Thanks to FlightGlobal.com for the alert.