<h3><font color = "blue">Cessna: 560; Cracked Threshold Frame; ATA 5344</font></h3>
<p>A repair station technician describes what has become a routine discrepancy on this Cessna jet. “The cabin entry threshold <em>(was found) </em>cracked at the aft step attach bolt hole. The probable cause <em>(may be) a </em>combination of the bolt hole having been located in the radius of the frame <em>(P/N 5511249-14S) </em>and the material thickness not sufficient to support the weight of personnel entering or exiting the aircraft. I recommend strengthening the structure by using thicker metal.” He notes approximately 75 percent of these model 560 aircraft are found with cracks in this threshold part. </p>