Narrative:

There is a task card on the crj 200 numbered 78-900-100 to perform an ops check of the thrust reverser system. I feel this task card needs to be rewritten to include the caution stated in the temporary revision 78-30-00. Under rigging of thrust reverser with aircraft systems; the caution states: 'make sure that the thrust reverser is at the stow position when it is not used and the external power is connected. The pdu arming and stow/deploy solenoids are always energized when the thrust reverser (T/right) is more than 0.125 inch from the stow position. If the pdu arming and stow/deploy solenoids are energized for a long time; damage can occur.' now although the task card does state to obey precautions in 78-30-00; it does not state the caution above. It is common practice to deploy the T/rs during the course of maintenance in the night and leave them deployed until morning when it is convenient to move the aircraft outside for the actual ops check to be performed. This can result in the solenoids being left energized for many hours. I have seen this cause damage to a pdu in the past; resulting in the changing of the component. Update the task card 78-900-100 in step 1 notifying the technician of the danger to the pdu if the entire procedure is not performed all at once; and/or add a step to remove the cannon plugs that energize the solenoids if the procedure is not going to be completed right away. I do feel the best solution is to not deploy the T/rs until the maintenance base is ready to do the actual test of the system. It only takes 5 minutes to deploy them as described in step 1 of the task card. There is no need to leave them deployed all night.

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Original NASA ASRS Text

Title: CRJ200 Mechanic reports that thrust reverser's are being left deployed for extended periods of time during maintenance checks; in violation of a maintenance manual caution. The task card does not contain the caution in the manual.

Narrative: There is a task card on the CRJ 200 numbered 78-900-100 to perform an ops check of the thrust reverser system. I feel this task card needs to be rewritten to include the caution stated in the temporary revision 78-30-00. Under rigging of thrust reverser with aircraft systems; the caution states: 'Make sure that the thrust reverser is at the stow position when it is not used and the external power is connected. The PDU arming and stow/deploy solenoids are always energized when the thrust reverser (T/R) is more than 0.125 inch from the stow position. If the PDU arming and stow/deploy solenoids are energized for a long time; damage can occur.' Now although the task card does state to obey precautions in 78-30-00; it does not state the caution above. It is common practice to deploy the T/Rs during the course of maintenance in the night and leave them deployed until morning when it is convenient to move the aircraft outside for the actual ops check to be performed. This can result in the solenoids being left energized for many hours. I have seen this cause damage to a PDU in the past; resulting in the changing of the component. Update the task card 78-900-100 in step 1 notifying the Technician of the danger to the PDU if the entire procedure is not performed all at once; and/or add a step to remove the cannon plugs that energize the solenoids if the procedure is not going to be completed right away. I do feel the best solution is to not deploy the T/Rs until the maintenance base is ready to do the actual test of the system. It only takes 5 minutes to deploy them as described in Step 1 of the task card. There is no need to leave them deployed all night.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.