Narrative:

While taxiing back to the hangar; my sic (second in command) who was finishing up a cycle of IOE (initial operating experience) was taxiing the aircraft to enter the ramp. [I] looked down for no more than 5 seconds on the straightaway to organize my side pocket and remove some old papers and flight plans. I felt the aircraft turn and in my head realized this was way too early to be turning onto the ramp. I looked up and immediately yelled stop and my controls. I brought the aircraft to a stop to assess the situation. My sic turned the aircraft prior to where the assigned taxiway was located and we exited the taxiway onto the hard cement surface located between the ramp and taxiway. I assessed the situation; noticed no obstruction in front of the aircraft; and continued forward into the ramp. I parked the plane and had my sic shut the aircraft down. I checked the aircraft for damage from taxi lights we possibly could have hit; noted none. This incident was caused by the inexperience of my first officer who was a very low time sic. I should not have put my head down until the aircraft was parked and shut down. I got complacent having my first officer on a straightaway and should have been paying more attention to his actions. This all happened at the end of a 13 hour day after 7 hours of flying. It was day VFR. After we had the aircraft shut down I talked to my IOE sic about what happen and why it is important to follow taxiway centerlines and most of the time taxiway entrances are located after the sign that designates them.I talked to line service after the event and found out that this is not the first time this has happened when coming back into the ramp. The empty space between our ramp and the taxiway can be very misleading especially when someone is taxiing from the right seat. Although marked; the markings are few and far in between. I have seen some airports that paint areas like this green to simulate grass. It would be worth the suggestion to the airport authority to see if this is an option to prevent other occurrences of this.

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Original NASA ASRS Text

Title: Small transport Captain reported the First Officer taxied the aircraft off the taxiway onto a non-movement area.

Narrative: While taxiing back to the hangar; my SIC (Second in Command) who was finishing up a cycle of IOE (Initial Operating Experience) was taxiing the aircraft to enter the ramp. [I] looked down for no more than 5 seconds on the straightaway to organize my side pocket and remove some old papers and flight plans. I felt the aircraft turn and in my head realized this was way too early to be turning onto the ramp. I looked up and immediately yelled stop and my controls. I brought the aircraft to a stop to assess the situation. My SIC turned the aircraft prior to where the assigned taxiway was located and we exited the taxiway onto the hard cement surface located between the ramp and taxiway. I assessed the situation; noticed no obstruction in front of the aircraft; and continued forward into the ramp. I parked the plane and had my SIC shut the aircraft down. I checked the aircraft for damage from taxi lights we possibly could have hit; noted none. This incident was caused by the inexperience of my First officer who was a very low time SIC. I should not have put my head down until the aircraft was parked and shut down. I got complacent having my FO on a straightaway and should have been paying more attention to his actions. This all happened at the end of a 13 hour day after 7 hours of flying. It was Day VFR. After we had the aircraft shut down I talked to my IOE SIC about what happen and why it is important to follow taxiway centerlines and most of the time taxiway entrances are located after the sign that designates them.I talked to line service after the event and found out that this is not the first time this has happened when coming back into the ramp. The empty space between our ramp and the taxiway can be very misleading especially when someone is taxiing from the right seat. Although marked; the markings are few and far in between. I have seen some airports that paint areas like this green to simulate grass. It would be worth the suggestion to the airport authority to see if this is an option to prevent other occurrences of this.

Data retrieved from NASA's ASRS site 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.