Incident Description
An aircraft experienced an in-flight separation of the upper engine cowling from the nose section. The cowling subsequently lodged on the horizontal stabilizer. It remained in that position throughout the remainder of the flight and did not dislodge until after landing. During the landing rollout, the cowling fell off the stabilizer onto the runway.
Postflight Examination
A postflight examination of the recovered portions of the upper cowl was conducted. The examination focused on three fasteners contained within the cowl pieces. No damage or excessive wear was found on these fasteners. However, it was noted that the two front alignment pins, which attach the upper cowl to the lower cowl, were missing.
Findings
The investigation documented that the upper cowl separated in flight and remained on the stabilizer until the landing rollout. The missing alignment pins were identified as a condition of the cowl assembly, but no determination of when they were lost or whether their absence contributed to the separation was made in the source material.