Narrative:

On aircraft X gear swing maintenance was accomplished due to the re-servicing of the gear. After completing the gear swing; operations checked -- the aircraft was cleared for down-jacking. I asked 2 mechanics to assist me because the other mechanics who accomplished the gear swing operations check were signing off the task cards; non routines; and the tire change. I was at the nose and placed the chocks in place and was starting my walkaround when I was called over and told that we were going aircraft on ground for 2 fuel shrouds due to corrosion. He showed me the 2 shrouds. I made the comment; 'how come we couldn't find this yesterday when it was pulled out?' I also gave him the ipc for the shroud 28-20-00 figure 5. Mechanic then said; 'he's got the numbers they're on the part.' I turned and asked; 'how are we looking to my wing mechanics?' I heard 'good;' but can't tell you who said it. I turned to the nose gear; looked around and yelled out 'clear; reply was clear;' I again yelled our 'clear' and again received a clear. I said 'bring it down slowly.' just as we started lowering the jacks; a person (don't know who) from the tail yelled; 'stop!' the down-jack was stopped; as it forced the tail-jack to push the center clevis and pin down through the holding shaft. The aircraft was raised to clear the situation and the down-jacking operation was stopped. The supervisor was notified of the situation. Under no circumstances allow oneself to be pulled from the initial train of thought and sidetracked from the task in hand. The information about the fuel shroud could have waited until I had finished my walkaround. Another resourceful procedure that I will accomplish is; instead of calling out each wing as I did; I think that in the future I call out left wing clear; right wing clear; tail clear; one extra step and it will send a set of eyes to look at the tail stand and that location. Callback conversation with reporter revealed the following information: reporter stated the tail stand is not actually a jack; but a tripod hard stand; with a center shaft; that has multiple position holes. These holes allow for various height adjustments of the vertical center shaft. The top of the shaft has a curved wooden block that is positioned under the fuselage tail section; approximately six inches aft of the aft equipment access panel; along a rib and double row of fasteners. The tail stand is not designed to support the crj-100 during the jacking or de-jacking process; only to act as a balance when the main and nose jacks are used. Reporter stated; as a lead mechanic; he normally does a walkaround prior to any jacking or de-jacking procedure. But on that day; he was distracted by another mechanic's fuel shroud issue and never completed his walkaround. He didn't see the tail stand. The weight of the fuselage tail section collapsed the center shaft of the tail stand; pushed in the fuselage skin; and buckled the fuselage rib. The skin was reworked; but the rib required replacement. The engine oil service electric pump is attached to and supported by that same rib at the same location.

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Original NASA ASRS Text

Title: A Lead Mechanic describes the chain of events that led to fuselage tail damage on a CRJ-100 during a down-jacking procedure.

Narrative: On Aircraft X gear swing maintenance was accomplished due to the re-servicing of the gear. After completing the gear swing; operations checked -- the aircraft was cleared for down-jacking. I asked 2 mechanics to assist me because the other mechanics who accomplished the gear swing operations check were signing off the task cards; non routines; and the tire change. I was at the nose and placed the chocks in place and was starting my walkaround when I was called over and told that we were going Aircraft on Ground for 2 fuel shrouds due to corrosion. He showed me the 2 shrouds. I made the comment; 'How come we couldn't find this yesterday when it was pulled out?' I also gave him the IPC for the shroud 28-20-00 Figure 5. Mechanic then said; 'he's got the numbers they're on the part.' I turned and asked; 'How are we looking to my wing mechanics?' I heard 'good;' but can't tell you who said it. I turned to the nose gear; looked around and yelled out 'clear; reply was clear;' I again yelled our 'clear' and again received a clear. I said 'bring it down slowly.' Just as we started lowering the jacks; a person (don't know who) from the tail yelled; 'stop!' The down-jack was stopped; as it forced the tail-jack to push the center clevis and pin down through the holding shaft. The aircraft was raised to clear the situation and the down-jacking operation was stopped. The Supervisor was notified of the situation. Under no circumstances allow oneself to be pulled from the initial train of thought and sidetracked from the task in hand. The information about the fuel shroud could have waited until I had finished my walkaround. Another resourceful procedure that I will accomplish is; instead of calling out each wing as I did; I think that in the future I call out left wing clear; right wing clear; tail clear; one extra step and it will send a set of eyes to look at the tail stand and that location. Callback conversation with Reporter revealed the following information: Reporter stated the tail stand is not actually a jack; but a tripod hard stand; with a center shaft; that has multiple position holes. These holes allow for various height adjustments of the vertical center shaft. The top of the shaft has a curved wooden block that is positioned under the fuselage tail section; approximately six inches aft of the aft equipment access panel; along a rib and double row of fasteners. The tail stand is not designed to support the CRJ-100 during the jacking or de-jacking process; only to act as a balance when the main and nose jacks are used. Reporter stated; as a Lead Mechanic; he normally does a walkaround prior to any jacking or de-jacking procedure. But on that day; he was distracted by another mechanic's fuel shroud issue and never completed his walkaround. He didn't see the tail stand. The weight of the fuselage tail section collapsed the center shaft of the tail stand; pushed in the fuselage skin; and buckled the fuselage rib. The skin was reworked; but the rib required replacement. The engine oil service electric pump is attached to and supported by that same rib at the same location.

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.