An A319 inlet cowling was damaged during maintenance when the hoist mechanism used to remove it failed; due to improper utilization. Vague operating instructions and inexperienced personnel may have contributed.

Narrative

I was assigned to the A319 along with two other Techs. After going to the gate and picking the plane up we towed it to the hanger line. Our first task was to remove and install the #2 engine inlet. We all agreed to assignments. I was to remove the upper half bolts and connections; the second Tech was to remove the lower half bolts and connections; and the third was to grab the engine inlet sling and adapter for the hoist. When the sling arrived my team members connected it to the engine inlet best they could with vague directions. Once ready to remove the inlet we proceeded to raise and create separation of the inlet from the engine. Suddenly the adapter for the hoist flipped off forward and fell onto both engine fan cowls putting holes into the upper forward areas. After realizing the damage we removed most of the tooling and I notified the Lead Mechanic who came to our aide and continued to help us remove the damaged inlet. Once the sling was partially reattached I noticed that one bolt on the lower half at the five o'clock position was still attached. We removed the bolt and proceeded to put the inlet on the ground. I believe it occurred because there were not enough experienced workers involved with operating the engine sling and adapter.All three of us were removed from the job upon the completion of a drug and alcohol analysis. The job was finished before shift's end by other crew members. We as employees were required to make a written statement. We were also required to meet with Supervisors for a verbal statement; and we spoke on the phone with our Safety Committee on how this could have been prevented and what improvements could have been made. Once realizing how it occurred; I believe there could have been an illustration on the different types of apparatus that allows you to remove the inlet from the engine; whether it be overhead crane or fork lift adapters. These illustrations need to be posted on the task card itself to prevent further incidents. If the adapter was secured; whether a bolt was accidentally left in the inlet or not; this would have prevented any further damage. I also would like to see another experienced adapter operator with the crew.