Incident Overview
Description
Crashed into a garage shortly after take off for Bergamo. Examination of the propeller assemblies indicated that, although the right-hand propeller appeared to have been at fine pitch and rotating at high revolutions at impact, the left-hand propeller had been rotating much more slowly and appeared to have been at, or close to, its fully feathered position. The firewall shut-off fuel valve for the left-hand engine was found in its closed position, consistent with the action of shutting down this engine at some point prior to the impact. A strip examination of the left-hand engine was conducted and showed no evidence of damage to its rotating assemblies prior to the impact with the garage. The only damage identified on this engine as not being consistent with the impact was a ruptured diaphragm within the low-pressure compressor bleed valve. This rolling diaphragm is designed to hold the compressor bleed valve closed a high power settings and to provide smooth opening of the compressor bleed valve with reduction of compressor discharge pressure.
Source of Information
http://www.aaib.gov.uk/cms_resources.cfm?file=/Beechcraft%20Super%20King%20Air%20200,%20G-WSJE%20%2009-88.pdfhttp://www.aaib.gov.uk/cms_resources.cfm?file=/Beechcraft%20Super%20King%20Air%20200,%20G-WSJE%20%2009-88.pdfPrimary Cause
Faulty low-pressure compressor bleed valve diaphragm.Faulty low-pressure compressor bleed valve diaphragm.Share on:
