Narrative:

[It was the] first flight of the day; early sign in. The aircraft had the following MEL's active: 34-09 flight director system; 34-25 head-up display; 34-15 number 1 radio altimeter system; 32-13B pseu fault system; 22-89B lmp status downgrade; 33-02 forward entry cabin interior light. Each MEL was read and discussed prior to the 'before starting engines' checklist being started. Abnormal conditions generated by the MEL items were discussed. The first officer was to fly the leg as his flight director and radio altimeter was operative. When the MCP was set up the first officer's flight director showed 'ma'; verifying in my mind his was the 'master' and my flight director was driven by his. I had also discussed the fact there were no specific instructions in the MEL to place the 'slaved' side switch 'off'; and no instructions to place a placard on the switch. I mentioned I thought this odd; as normally inoperative system MEL's specifically direct switch position and placard placement. I have learned that the 737 programming is very specific; and not entirely intuitive; and reasoned that perhaps some programming required the flight director switch not be placed 'off'; and verified again that the first officer's flight director showed 'ma'. After take off; we had some odd indications; including a 'flare' mode annunciation in the climb out. I obtained a radio patch with maintenance and discussed the matter with them. They indicated the captain's flight director switch should be 'off'. I said I thought that if the first officer's flight director showed 'ma' it was the master and driving the captain's side. They said they believed that was incorrect. I placed the captain's flight director switch 'off' and the 'flare' annunciation extinguished. It remained off for the remainder of the flight. I also looked up the system description in the operating manual volume 2 and saw I was mistaken; that although 'ma' did indicate which side was the 'master'; it was the master flight control computer; and not the master flight director. As soon as I read that I remembered that it was master flight control computer; and not flight director; and was professionally embarrassed by my inaccurate system memory during my brief. I then went back to the MEL to see if I had missed some direction to turn the inoperative flight director switch 'off' and place an 'inoperative' sticker over it in the maintenance actions required. I did not remember any from my MEL review earlier; but wanted to verify I had not somehow missed something. There were no such directions for maintenance or operator actions. The error was mine and based upon an inaccurate memory of the 'ma' annunciation and the flight director system during my preflight brief; and fed by the specific lack of direction to switch off and placard the system in the MEL. I believe that if the flight director is inoperative and placed on an MEL; and then either the mechanic or the crew should be directed by the MEL to place the inoperative side flight director switch 'off'; and install one of the small 'inoperative' stickers at that switch. That removes any chance of misinterpretation of the system or the procedures to follow. That has been the standard procedure for inoperative systems on the six other aircraft I have flown; and seems to me to be the most prudent as well. I can see no reason to not include this step and think my error provides a reasonable argument for its inclusion in the MEL.

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Original NASA ASRS Text

Title: B737-800 Captain reports being dispatched with his Flight Director MEL'ed and the First Officer flying. Odd annunciations prompt the crew to contact Maintenance; and are informed that the Captain's Flight Director switch should be in the off position. This step is not in the MEL.

Narrative: [It was the] first flight of the day; early sign in. The Aircraft had the following MEL's active: 34-09 Flight Director System; 34-25 Head-Up Display; 34-15 Number 1 Radio Altimeter System; 32-13B PSEU Fault System; 22-89B LMP Status downgrade; 33-02 Forward Entry Cabin Interior Light. Each MEL was read and discussed prior to the 'Before Starting Engines' checklist being started. Abnormal conditions generated by the MEL items were discussed. The First Officer was to fly the leg as his Flight Director and Radio Altimeter was operative. When the MCP was set up the First Officer's Flight Director showed 'MA'; verifying in my mind his was the 'master' and my flight director was driven by his. I had also discussed the fact there were no specific instructions in the MEL to place the 'slaved' side switch 'OFF'; and no instructions to place a placard on the switch. I mentioned I thought this odd; as normally inoperative system MEL's specifically direct switch position and placard placement. I have learned that the 737 programming is very specific; and not entirely intuitive; and reasoned that perhaps some programming required the Flight Director switch not be placed 'OFF'; and verified again that the First Officer's Flight Director showed 'MA'. After take off; we had some odd indications; including a 'Flare' mode annunciation in the climb out. I obtained a radio patch with Maintenance and discussed the matter with them. They indicated the Captain's Flight Director switch should be 'OFF'. I said I thought that if the First Officer's Flight Director showed 'MA' it was the master and driving the Captain's side. They said they believed that was incorrect. I placed the Captain's Flight Director switch 'OFF' and the 'Flare' annunciation extinguished. It remained off for the remainder of the flight. I also looked up the system description in the Operating Manual Volume 2 and saw I was mistaken; that although 'MA' did indicate which side was the 'master'; it was the master Flight Control Computer; and not the master Flight Director. As soon as I read that I remembered that it was master Flight Control Computer; and not Flight Director; and was professionally embarrassed by my inaccurate system memory during my brief. I then went back to the MEL to see if I had missed some direction to turn the inoperative Flight Director switch 'OFF' and place an 'INOP' sticker over it in the Maintenance actions required. I did not remember any from my MEL review earlier; but wanted to verify I had not somehow missed something. There were no such directions for Maintenance or Operator actions. The error was mine and based upon an inaccurate memory of the 'MA' annunciation and the flight director system during my preflight brief; and fed by the specific lack of direction to switch off and placard the system in the MEL. I believe that if the flight director is inoperative and placed on an MEL; and then either the Mechanic or the Crew should be directed by the MEL to place the inoperative side Flight Director switch 'OFF'; and install one of the small 'inoperative' stickers at that switch. That removes any chance of misinterpretation of the system or the procedures to follow. That has been the standard procedure for inoperative systems on the six other aircraft I have flown; and seems to me to be the most prudent as well. I can see no reason to not include this step and think my error provides a reasonable argument for its inclusion in the MEL.

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.