Narrative:

Upon arrival to aircraft I noted the co-pilot pre-flighting aircraft for departure. We ran through the pre-start checklists which include 'pre-flight inspection complete' and began our taxi for the runway. After rotation; the co-pilot called for 'gear up' and I responded by moving gear selector to 'retract' position. After this action we noted that the gear remained three green 'down' [lights] even after multiple attempts to change its position. I notified ATC that we would be returning to the field and ran the applicable checks prior to our return. We landed on the runway and taxied to our hangar.on post flight inspection; we pinned the landing gear and inspected the three-way selector valve on the stub wing. I verified it was in the proper position and waited until maintenance personnel arrived. It was later discovered that the valve was slightly ajar thus preventing us from moving the gear. A conversation with maintenance personnel later in the day confirmed that they had cycled the emergency landing gear deployment system and reset it only from the cockpit (must also be reset at selector valve). In order to not duplicate this scenario again; I will be meeting with maintenance personnel to better understand the hydraulic landing gear system. I will pass this knowledge to all pilots in our company so we can be on the lookout for these defects on our pre-flight inspections. I will also double check major parts of the pre-flight as two sets of eyes can only be beneficial when it comes to a safe aircraft.

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Original NASA ASRS Text

Title: A Captain of a Short 360-300 aircraft reports not being able to retract the landing gears during initial climb; requiring an air turnback. A three-way selector valve in the right stub wing had not been reset by maintenance after they had serviced the emergency landing gear deployment accumulator and recycled the emergency 'T' handle in the cockpit.

Narrative: Upon arrival to aircraft I noted the Co-pilot pre-flighting aircraft for departure. We ran through the Pre-start Checklists which include 'pre-flight inspection complete' and began our taxi for the runway. After rotation; the Co-pilot called for 'Gear Up' and I responded by moving gear selector to 'retract' position. After this action we noted that the gear remained three green 'down' [lights] even after multiple attempts to change its position. I notified ATC that we would be returning to the field and ran the applicable checks prior to our return. We landed on the runway and taxied to our hangar.On post flight inspection; we pinned the landing gear and inspected the Three-way Selector Valve on the stub wing. I verified it was in the proper position and waited until Maintenance personnel arrived. It was later discovered that the valve was slightly ajar thus preventing us from moving the gear. A conversation with maintenance personnel later in the day confirmed that they had cycled the Emergency Landing Gear deployment system and reset it only from the cockpit (must also be reset at Selector valve). In order to not duplicate this scenario again; I will be meeting with Maintenance personnel to better understand the hydraulic landing gear system. I will pass this knowledge to all pilots in our company so we can be on the lookout for these defects on our pre-flight inspections. I will also double check major parts of the pre-flight as two sets of eyes can only be beneficial when it comes to a safe aircraft.

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.