Cracks in Cirrus SR line power lever
By Rafael Payao
When starting takeoff, a Cirrus SR20 had the power lever broken in half, at the exact moment the pilot advanced the lever to full power setting. After the engine was cut off by the mixture lever, the aircraft could be taken to the hangar, without major disruption and without configuring an operational safety event.
However, in order to investigate the case, the operator of a Cirrus training fleet initially conducted a visual examination of other examples, revealing that in another 24 aircraft there were cracks in the region where the smallest cross-section can be seen. The inspections were later complemented by non-destructive liquid penetrant tests.
However, the FAA issued an ACS, which in a liberal translation would be a letter of airworthiness concern, which becomes a first step towards the possibility of a future AD/DA (Airworthiness Directive). In this letter, the FAA encourages all operators to inspect the power levers of their Cirrus (SR20 and 22 family) and send information about possible damage, fractures or cracks to the agency in order to support the best aviation safety practices.
Finally, the aircraft found with the defective power lever were in regular use in flight training, having accumulated between 2.900 and 3.900 hours in service and between 12.000 and 15.000 landings.
