MD-11
Confusion; Distraction; Situational Awareness; Time Pressure; Troubleshooting; Workload; Communication Breakdown
Aircraft Equipment Problem Critical
General Maintenance Action
Aircraft; Company Policy; Procedure; Human Factors; MEL
Aircraft was carrying five deferrals upon our arrival. One was subsequently cleared. The First Officer and I reviewed all MELs together to ensure that we complied with all requirements. One of the remaining deferrals was MEL 78-30-01-B; Thrust Reversers - PW (Engine Number 3 Thrust Reverser - Inoperative). We reviewed the Operations Notes and complied with them. I noticed during my preflight that the Number 3 EPR gauge was indicating a green 'REV'. The green REV indicates that the reverser is fully deployed on the ground. I did not think too much about the indication for several reasons: I thought this indication was associated with the MEL and the aircraft had already flown several times with this deferral; I knew that the reverser was not deployed as I had visibly checked the Number 3 Engine in my scan as I walked to the right side of the aircraft during my exterior inspection (the purpose of my walk to the right side was to intentionally observe the engine as I like to mentally review the physical differences between the Pratt and GE engines from time to time).My very competent First Officer performed the walk around and did not mention the reverser being deployed; the local mechanics are extremely experienced with the MD-11; and the MEL is silent with regard to whether this was a normal indication due to the maintenance deferral actions. I have seen on several occasions; where a deferral leads to an Alert or Indication not specifically mentioned in the MEL procedure. All of these reasons plus the difficulties associated with the preflight due to missing manuals; incomplete ACARS transmissions and the additional administrative workload associated with a planned maintenance stop flight; caused me to assign the green REV indication as a non-threat item. The aircraft performed normally during taxi and takeoff with regard to performance - no yaw or acceleration issues. Right after rotation- the green REV indication turned red; which means the reverser is fully deployed in-flight. That caught my attention; but simultaneously knew the plane was flying normally. After we were underway and well above 10;000 FT; the First Officer mentioned that Red REV [indication] initially caused him some concern as well. We discussed the situation a little more and I told him that I would contact Maintenance Control via SATCOM after level off to see if that was a 'normal' indication due the MEL. In the interim; I referenced the Reverser Deployed Or U/L Or Rev Displayed Inflight checklist in the QRH. I showed the First Officer the checklist and subsequently completed it. (U/L denotes that the reverser is unlocked). After level off; we contacted Maintenance Control and were connected with Mr. X in Powerplants. I informed him of what we had and asked if this was normal; as I have had this item deferred before but could not recall if it was on a General Electric (GE) or Pratt-Whitney (PW) engine. Mr. X stated that this was 'not normal'. I asked him what they wanted us to do. He told us to write it up and he would call ahead to ZZZZ1 for us. Afterwards; we both thoroughly reviewed the MEL to see if we had missed anything and verified to the extent possible that the maintenance actions were complied with accordingly (i.e. Circuit Breaker pulled and collared). During our review it became apparent that there are differences in the maintenance actions for the GE deferral (78-30-01-A). Specifically it says in Step 10: 'If the Amber U/L is displayed on the Engine and Alert Display (EAD) after securing the Thrust Reverser in the stowed position; MEL relief is NOT authorized. DO NOT disconnect any wires to extinguish a U/L Indication that is failed in the 'ON' state. Repairs must be made before flight.' There is no such corresponding restriction under the maintenance actions for the PW [Engine] for the U/L or REV [indication]. We called Mr. X back and pointed out the difference. Mr. X acknowledged that; but he stated that it is their policy not toDispatch an aircraft with an indication. We landed in ZZZZ1; the indication went back to green and the mechanics troubleshot the issue with Maintenance Control. The Reverser was completely stowed upon our arrival- bad indication. ZZZZ1 Maintenance eventually found dirt on one of the Cannon plugs; cleaned that off and that rectified the problem. They made the appropriate Corrective Action to my write-up and we departed uneventfully. [Recommend] the MEL relief needs to explicitly state that an indication is unacceptable or the Maintenance Policy needs to reflect the FAA authorized relief. As mentioned above; sometimes our MEL corrective actions lead to alerts and indications that are not necessarily explicitly stated in the relief for the crew's knowledge. I agree from a safety standpoint with our Maintenance Policy as a red REV indication in-flight can be an unnecessarily disturbing distraction. In retrospect; I should have brought this to the attention of the ZZZZ mechanics; although I'm not sure they would have thought the indication was abnormal as I assume they did a Post-Flight Inspection upon arrival in ZZZZ. Also; possibly instituting a Maintenance/Operations policy that an aircraft will carry less than five; (or pick a different number); deferrals at a time; so that the crew can more effectively manage all of the threats; could help prevent instances such as this.
We noticed during my preflight that the Number 3 EPR gauge was indicating a green 'REV'. The green 'REV' indicates that the reverser is fully deployed on the ground. I thought this indication was associated with the MEL and the aircraft had already flown several times with this deferral; I knew that the Reverser was not deployed; as I had visibly checked the Number 3 engine during my exterior inspection. The MEL is silent with regard to whether this was a normal indication. Right after rotation - the green 'REV' indication turned red; which means the reverser is fully deployed in flight. That caught my attention; but simultaneously knew the plane was flying normally. After leveloff; we contacted Maintenance Control and were connected with Mr. X in Powerplants. The Captain informed him of what we had and asked if this was normal. Mr. X in Powerplants stated that this was not normal. The Captain asked him what they wanted us to do. He told us to write it up and he would call ahead to ZZZZ1 for us. The rest of the flight was uneventful. Upon landing in ZZZZ1; the mechanics discovered a dirty Cannon plug. After cleaning it and reconnecting; the REV light extinguished. The ZZZZ1 mechanics also confirmed the reverser was fully stowed as we had figured.One area that would improve this MEL would be to clarify the unacceptable indications like REV light illuminated in the Operations section of the MEL. This is the wording on the same deferral for the GE motor. It would be helpful if the same wording was used for the PW engine MEL.
A Captain and First Officer report noticing the Number 3 Engine EPR gauge on their MD-11 aircraft had a green 'REV' (reverser) indication during their walkaround but the indication turned to red right after takeoff. Pilots noted the MEL relief needs to explicitly state that an indication is unacceptable or the Maintenance Policy needs to reflect the FAA authorized relief.