A US Federal Aviation Administration emergency airworthiness directive (AD) is instructing Raytheon Beech 1900 operators to conduct a visual inspection of their aircraft's rear wing spars before the next revenue flight after “significant cracks” were found during routine maintenance on two unidentified 1900Ds.
“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,” says the FAA.
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.
None of these problems was recorded at the 17,500h thorough inspection required by Raytheon’s structural inspection manual.
“Early indications show similar cracking on the other airplane. We continue to gather information on this airplane,” says the FAA, adding: “Analysis shows that similar cracks could also develop in the wings of the models 1900 and 1900C airplanes.”
The regulator also notes: “This is considered interim action. The FAA will use the data from the reporting requirement to determine what additional action is necessary, which could result in future AD action.”
According to Flight's fleet database ACAS, there are currently 651 1900s in operation.
Raytheon was not immediately available for comment.
Source: FlightGlobal.com