Cessna 310/T310C
Maintenance Inspection Authority; Maintenance Powerplant; Maintenance Airframe
Maintenance Inspector 28; Maintenance Technician 33
Situational Awareness; Time Pressure; Communication Breakdown; Distraction
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Other / Unknown
Aircraft Aircraft Damaged; Flight Crew Returned To Departure Airport; General Flight Cancelled / Delayed
Human Factors; Procedure
During troubleshooting of the cabin heater; located in the Nose Wheel Well (NWW); both Nose Landing Gear (NLG) doors were disconnected to gain access to the heater and components. One Mechanic was working on the heater; I was working on the Right engine. We were trying to get the aircraft back to service so the owner could use it for the holidays. It was on a weekend and we finally finished up the job late in the day. The other mechanics had left; only myself and an assistant were still at work. I pulled the aircraft out of the hangar for a post maintenance run-up; and to return it to the customer's hangar. I then returned to the Maintenance Hangar and completed the paperwork and log entries. It was getting late; and past time to go home. I notified the customer that the aircraft was ready. The aircraft flew a few days later in December and the landing gear would not retract properly. The landing gear was selected 'Down' and would not downlock. Two other attempts were made to extend the gear and it finally downlocked. A routine landing was made with no incident. There was some damage to the nose landing gear doors. I believe one section of the job was not completed due to the Mechanic being pulled off to another job. I trusted the Mechanic to do his job; and did not catch the disconnected doors as I pulled the aircraft out of the hangar. To keep this from happening; an orange streamer should have been attached to the nose gear door actuator arms to call attention to the doors; with the mechanic's name on it; to be removed only by that mechanic.
An Aircraft Maintenance Technician (AMT) reports a Cessna 310 aircraft returned to field after the Nose Landing Gear (NLG) would not retract. He failed to notice that both NLG door actuator arms had not been reconnected by another Mechanic who had been working on a cabin heater located in the NLG wheel well.