Narrative:

After the aircraft walkaround and preflight checks were completed, a mechanic came to the airplane to resolve 2 logbook items. While checking a discrepancy and sitting in the captain's seat he noticed that the nose gear mechanical downlock indicator was low. He stated that it probably should be adjusted higher. I said that I had seen the indicators in this low of a position before. He then called on the phone for help and further clarification. I then believe that he went outside to look at the nose gear. During this time a mechanic supervisor came in to the cockpit and we discussed the indicator. We both decided that it was all right to go the way it was. With mechanics off, agent closed the door and then we taxied out for takeoff. After takeoff and with gear up, there was a loud rumble. Accelerating made the noise louder. We slowed and asked ord departure for a return to the airport. Just before the turn back we put the gear down and with a gear safe indication we landed. We taxied back to the same gate and a mechanic met us. We told this new mechanic our indications. He went outside to check and found the nose gear forward doors still open. We then knew the first mechanic, who told us about the indicator pin, must have opened the doors and then left them open while leaving the airplane.

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Original NASA ASRS Text

Title: MD80 CREW RETURNED TO THEIR DEP STATION AFTER HEARING AND FEELING A RUMBLING AFTER GEAR RETRACTION.

Narrative: AFTER THE ACFT WALKAROUND AND PREFLT CHKS WERE COMPLETED, A MECH CAME TO THE AIRPLANE TO RESOLVE 2 LOGBOOK ITEMS. WHILE CHKING A DISCREPANCY AND SITTING IN THE CAPT'S SEAT HE NOTICED THAT THE NOSE GEAR MECHANICAL DOWNLOCK INDICATOR WAS LOW. HE STATED THAT IT PROBABLY SHOULD BE ADJUSTED HIGHER. I SAID THAT I HAD SEEN THE INDICATORS IN THIS LOW OF A POS BEFORE. HE THEN CALLED ON THE PHONE FOR HELP AND FURTHER CLARIFICATION. I THEN BELIEVE THAT HE WENT OUTSIDE TO LOOK AT THE NOSE GEAR. DURING THIS TIME A MECH SUPVR CAME IN TO THE COCKPIT AND WE DISCUSSED THE INDICATOR. WE BOTH DECIDED THAT IT WAS ALL RIGHT TO GO THE WAY IT WAS. WITH MECHS OFF, AGENT CLOSED THE DOOR AND THEN WE TAXIED OUT FOR TKOF. AFTER TKOF AND WITH GEAR UP, THERE WAS A LOUD RUMBLE. ACCELERATING MADE THE NOISE LOUDER. WE SLOWED AND ASKED ORD DEP FOR A RETURN TO THE ARPT. JUST BEFORE THE TURN BACK WE PUT THE GEAR DOWN AND WITH A GEAR SAFE INDICATION WE LANDED. WE TAXIED BACK TO THE SAME GATE AND A MECH MET US. WE TOLD THIS NEW MECH OUR INDICATIONS. HE WENT OUTSIDE TO CHK AND FOUND THE NOSE GEAR FORWARD DOORS STILL OPEN. WE THEN KNEW THE FIRST MECH, WHO TOLD US ABOUT THE INDICATOR PIN, MUST HAVE OPENED THE DOORS AND THEN LEFT THEM OPEN WHILE LEAVING THE AIRPLANE.

Data retrieved from NASA's ASRS site as of July 2007 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.