B737 MAX technicians and Inspector reported there was a lack of compliance with procedures with the repair of an aircraft that had a discrepancy with the elevator trim. Damage had been discovered to structural components within the center pedestal and was misidentified to be within limits.
Synopsis
B737 MAX technicians and Inspector reported there was a lack of compliance with procedures with the repair of an aircraft that had a discrepancy with the elevator trim. Damage had been discovered to structural components within the center pedestal and was misidentified to be within limits.
Narrative
Aircraft X was inbound into ZZZ and came in with a discrepancy that the Elevator Electric Trim Chain was making a slapping noise when trimming the elevator. Aircraft was taken out of service and remained overnight. I worked graveyard shift on overtime and got assigned to troubleshoot the issue with the slapping chain for the electric trim. I adjusted the lower and bottom control turnbuckles in reference to the Aircraft Maintenance Manual with no help. Troubleshot the issue some more and found that the chain was still really loose. I adjusted the spool bolts by turning the nuts less then 1/4-inch. This fixed the issue and the chain was in limits per the Maintenance Manual. The technicians that initially found the issue that the chain was loose found that the chain had been rubbing on a frame in the pedestal.Talking to Management; it was determined that the damage wasn't that bad so the Management team edited the original write-up and deleted the pictures when I went to sign the original write-up off. There was no write-up in Maintenance saying there was any damage. I signed the aircraft off and Aircraft X was returned to service. Forty five minutes later the Inspector that performed my RII (Required Inspection Item) function; Person A; determined the Upper Turnbuckle Rod End was bent after they had already signed the aircraft of as being airworthy. They determined the Rod End was bent because they went and looked at other MAX aircraft. I ordered a new Rod End and I continued to be on shift. The Rod End came in at XF:00. I installed the new serviceable Rod End and rigged the Rod End in reference to Maintenance Manual. Inspector proceeds to tell me that they rewrote the damage up because they were accusing me of deleting the write-up and removing the pictures of the damage; which I can't do but Management can.Aircraft X goes back out of service and is still in ZZZ; has never flown since the initial squawk. I feel like I did nothing wrong and am getting accused of things I did that never happened and as far as the Rod End being bent. I looked at other aircraft and it didn't look bent to me but it was bent. The Inspector has the final say and they didn't see it either because they released the aircraft back into service. The aircraft is still here in ZZZ getting the Elevator Trim Chain replaced and the damage blended out so the aircraft hasn't flown since the initial discrepancy.Get inspectors trained on the aircraft because it's obvious [the] Inspector didn't know what they were looking for because why did they initially sign it off. Inspection is the final say.
Second reporter narrative
On Day 0; I was scheduled the duty of RII (Required Inspection Item) buyback for Aircraft X inbound write-up; 'Trim wheel makes loud noises while trimming all places.' At the beginning of the shift I began looking into the discrepancy. While reviewing the write-up; I saw 4 total pictures where AMT B shows they discovered the Stab Trim Control Chain being very loose. Two of the photos showed a zoomed in view of what appeared to be structural damage where the chain had worn grooves into the structure as a result of it being loose. Shortly after the beginning of the shift; my Supervisor informed me that the decision was to not work that aircraft on the overnight shift. At around XA:00; I received a phone call from the Lead that they were ready for inspection buyback for the chain adjustment. I had explained that I was told it wasn't being worked; otherwise I would have been there from the start of the task; but I would go and be able to check the adjustment.While looking in the Forward EE Bay; I found that the upper turnbuckle had a bent Rod End. When I talked to the Mechanic that did the adjustment AMT A; I asked if they saw the bent Rod End. They said they had originally thought it was bent also; but had compared it to another aircraft and that it was 'supposed to be that way.' AMT A is a well known knowledgeable Mechanic so I believed they had done as they said so I went ahead and signed off the chain adjustment since that in itself was correct and I wrongly made the decision to WAIT on making a write-up about the Rod End until I had done more research and verified myself. Also while in the EE I searched for the suspected damage that I had seen earlier; which I did not find. After not seeing the damage; I decided to review the photos again to help me locate where the photo was taken. At this point I find in tracking system that TWO out of the four photos have been removed from the discrepancy; and no write-ups have been made that addressed the suspected damage. I asked the two mechanics if they knew what happened to the missing photos. Their response was NO. I asked if they deleted the photos. Their response was NO; and that [the] tracking system did not give the mechanics the ability to remove photos. The mechanics acknowledged that there were other photos attached but did not know what happened to them.I asked AMT B where the suspected damage was located; and they explained it could only be seen from the cockpit behind the pedestal panels that were already re-installed; but that the damage 'looked worse than it really was in the pictures; and that it was only paint.' At this point I wrongly thought that I would be outside of my scope of inspection to have the mechanics re-open the panels for what they say was 'only paint.' So at this point the adjustment is signed off because the tensions showed to be within limits. The plane was released to service due to the Lead not knowing the Rod End was found bad. I should have made a more timely write-up for the Rod End so that the work package wouldn't be closed. I informed them that the Rod End was found to be bad and that I would be creating a new work package write-up to replace the Upper Turnbuckle Rod End. The aircraft becomes AOG for the turnbuckle.When the day shift Supervisor comes in; I inform them of everything above including the missing photos; and my suspicion on if there is damage I saw in the photos. They explained I was wrong about staying within my scope; and that if I suspect damage that we should get the panels back open and verify. After opening the panels we found the damage was more than 'paint' - [it] was two grooves in the structure as a result of the chain riding on the structure. The damage was 0.100 inches width with a depth of 0.050 inches.In conclusion; although I made the write-ups in the end; I should have made the turnbuckle write-up as soon as I found it; regardless of whether there was uncertainty on if it was correct or not. Regarding the suspected damage; I should have made the call immediately to remove the panels so I could verify if there was damage that I believe I saw in the missing photos. In the future I will immediately write up discrepancies and THEN investigate whether they are right or wrong. I will do this in order to prevent the work package being closed and released to service with a suspected discrepancy. As far as the suspected damage goes; I know now that any suspected damage should immediately be investigated and documented even if I believe it is outside of my scope. As Quality Control Inspector it is my job to investigate any suspected damage regardless of scope in order to provide a safe aircraft. SAFETY COMES BEFORE SCOPE!
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Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.