Interim Recommendation IR19990187

Interim Recommendation issued to: Cessna Aircraft Company

Recommendation details
Output No: IR19990187
Date issued: 16 December 1999
Safety action status:
Background: Why this Interim Recommendation was developed

Output text

The Australian Transport Safety Bureau (formerly BASI) recommends that Cessna Aircraft Corporation take appropriate action to ensure that Cessna elevator trim-tab actuator component parts affected by this safety deficiency are recoded so that they cannot be purchased separately. In addition, it is recommended that Cessna Aircraft Corporation review comparable designed trim-tab actuators to ensure that they are not affected by this safety deficiency.

As a result of the investigation into this occurrence, the Bureau simultaneously issues the following safety advisory notices:


The Civil Aviation Safety Authority should note the safety deficiency identified in this document and take appropriate action.


The US Federal Aviation Administration should note the safety deficiency identified in this document and take appropriate action.


The US National Transportation Safety Board is advised of the recommendation made to the aircraft manufacturer and safety advisory notices issued to the Civil Aviation Safety Authority and the US Federal Aviation Administration.

Initial response
Date issued: 13 March 2000
Response from: Cessna Aircraft Company
Action status: Closed - Accepted
Response text:

In reviewing your Interim Recommendation, Cessna Product Engineering agrees with the stated recommendation to code the replaceable components of the actuator assembly such that a matched set of components, i.e., the male externally threaded component and the female internally threaded component cannot be purchased separately from the factory. After looking into the other aircraft in the 300/400 Series, our engineers have begun to identify a system in use on all models of Cessna aircraft and not just the Model 402 for the functions of elevator trim tab, rudder rim tab, as well as aileron trim tab. We believe that all actuators of this type and variety should be coded together.

The Cessna Spare Parts Division, CPD-2, will code all suspect threaded actuator components accordingly once Product Engineering has completed the task of researching and establishing the respective parts and/or assemblies with their appropriate effectivities and high assemblies.

Our engineers have completed the research on the Model 402 aircraft, and will be ready to submit the data to Mr [name] at CPD-2 Spares early next week. The task is somewhat complex to identify all of the suspect components, however, we are making progress in this area. I will be working to ensure the engineers are able to develop a complete, concise list of actuator assemblies and the suspect components which must be identified for the remainder of the 300/400 models.

It is unfortunate many operators are failing to adequately comply with the warnings and notes in the Maintenance Manuals stipulating the type of lubricants and the intervals at which service must occur, as well as the noted components which are recommended to be replaced as a set during overhauls. Aside from coding the parts, there appears to be little else that can be done to insure the operators and maintenance engineers adhere to the guidelines as outlined in the aircraft service manuals.

Last update 01 April 2011