Narrative:

I completed the overnight line check on aircraft X and was preparing to go inside and finish the paperwork and enter it, when the maintenance manager called and asked if we could bring it to the gate as soon as possible for a flight. The aircraft was not scheduled to fly until the next day, but I told the manager we would finish the paperwork and bring it to the gate. Technician Y was working with me and asked if he should go out to the plane and do the walk around, I said no that I would do that and for him to pick up the logbooks and meet me at the plane. I went to the cockpit and proceeded to ready the plane for taxi. Technician returned with the logbooks, and we taxied to the gate. While signing off the paperwork and logbooks, technician Y said that he signed off the landing gear pins. I believe now that technician Y had signed off removing the gear pins, because he thought that since I had completed the walkaround, that I had already done it, whereas I thought that since he had signed them off, he had removed them. The flight crew did not see the gear pins on their walkaround, and the plane took off. When the landing gear would not retract, the aircraft returned to ZZZ, had the pins removed, and continued on without further incident.

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Original NASA ASRS Text

Title: A DC9-30 WAS DISPATCHED IN NON COMPLIANCE WITH GEAR PINS INSTALLED AND NOT REMOVED PRIOR TO FLT.

Narrative: I COMPLETED THE OVERNIGHT LINE CHK ON ACFT X AND WAS PREPARING TO GO INSIDE AND FINISH THE PAPERWORK AND ENTER IT, WHEN THE MAINT MGR CALLED AND ASKED IF WE COULD BRING IT TO THE GATE ASAP FOR A FLT. THE ACFT WAS NOT SCHEDULED TO FLY UNTIL THE NEXT DAY, BUT I TOLD THE MGR WE WOULD FINISH THE PAPERWORK AND BRING IT TO THE GATE. TECHNICIAN Y WAS WORKING WITH ME AND ASKED IF HE SHOULD GO OUT TO THE PLANE AND DO THE WALK AROUND, I SAID NO THAT I WOULD DO THAT AND FOR HIM TO PICK UP THE LOGBOOKS AND MEET ME AT THE PLANE. I WENT TO THE COCKPIT AND PROCEEDED TO READY THE PLANE FOR TAXI. TECHNICIAN RETURNED WITH THE LOGBOOKS, AND WE TAXIED TO THE GATE. WHILE SIGNING OFF THE PAPERWORK AND LOGBOOKS, TECHNICIAN Y SAID THAT HE SIGNED OFF THE LNDG GEAR PINS. I BELIEVE NOW THAT TECHNICIAN Y HAD SIGNED OFF REMOVING THE GEAR PINS, BECAUSE HE THOUGHT THAT SINCE I HAD COMPLETED THE WALKAROUND, THAT I HAD ALREADY DONE IT, WHEREAS I THOUGHT THAT SINCE HE HAD SIGNED THEM OFF, HE HAD REMOVED THEM. THE FLC DID NOT SEE THE GEAR PINS ON THEIR WALKAROUND, AND THE PLANE TOOK OFF. WHEN THE LNDG GEAR WOULD NOT RETRACT, THE ACFT RETURNED TO ZZZ, HAD THE PINS REMOVED, AND CONTINUED ON WITHOUT FURTHER INCIDENT.

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.