Narrative:

Designed runway heading for departure on runway 34. At approximately 900' AGL, forward cabin door ajar warning annunciator illuminated. We were still under tower control. At this point I cleared the airspace to my left to prepare for a left downwind pattern to land on 34. Tower was busy talking to someone else, so I began my turn to enter downwind. Tower finished talking with the other aircraft and then asked me why I was not on runway heading. I explained the annunciator light problem and he cleared us to land on 34. We landed without incident. There were no other aircraft in the area at the time. There are many reasons for my immediate turn back towards the airport. I do not have complete confidence in the door latching mechanism on this aircraft. Our company recently experienced an in-flight door opening and subsequent airstair door sep on this type aircraft. The airstair door in question in located directly in front of the left propeller. The aircraft that experienced the opening and sep of this door miraculously made it to a runway in one piece. Our company's most experienced light transport pilots (myself included) and our most trusted mechanics all believe that the next time a door comes off this type light transport it could prove catastrophic. Looking back, I believe I did the proper thing when I immediately turned back toward the airport. At that instant, I did not know if it was an indication problem or if the door was going to open. The problem turned out to be an indication problem which I contribute to poor preventative maintenance, lack of the proper number of mechanics to work on these aircraft during the few, short night time hours that are available.

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Original NASA ASRS Text

Title: COMMUTER LTT DEVIATED FROM CLRNC HEADING FOR IMMEDIATE RETURN LAND DUE DOOR WARNING ACTIVATED AFTER TKOF.

Narrative: DESIGNED RWY HDG FOR DEP ON RWY 34. AT APPROX 900' AGL, FORWARD CABIN DOOR AJAR WARNING ANNUNCIATOR ILLUMINATED. WE WERE STILL UNDER TWR CTL. AT THIS POINT I CLRED THE AIRSPACE TO MY LEFT TO PREPARE FOR A LEFT DOWNWIND PATTERN TO LAND ON 34. TWR WAS BUSY TALKING TO SOMEONE ELSE, SO I BEGAN MY TURN TO ENTER DOWNWIND. TWR FINISHED TALKING WITH THE OTHER ACFT AND THEN ASKED ME WHY I WAS NOT ON RWY HDG. I EXPLAINED THE ANNUNCIATOR LIGHT PROB AND HE CLRED US TO LAND ON 34. WE LANDED WITHOUT INCIDENT. THERE WERE NO OTHER ACFT IN THE AREA AT THE TIME. THERE ARE MANY REASONS FOR MY IMMEDIATE TURN BACK TOWARDS THE ARPT. I DO NOT HAVE COMPLETE CONFIDENCE IN THE DOOR LATCHING MECHANISM ON THIS ACFT. OUR COMPANY RECENTLY EXPERIENCED AN INFLT DOOR OPENING AND SUBSEQUENT AIRSTAIR DOOR SEP ON THIS TYPE ACFT. THE AIRSTAIR DOOR IN QUESTION IN LOCATED DIRECTLY IN FRONT OF THE LEFT PROP. THE ACFT THAT EXPERIENCED THE OPENING AND SEP OF THIS DOOR MIRACULOUSLY MADE IT TO A RWY IN ONE PIECE. OUR COMPANY'S MOST EXPERIENCED LTT PLTS (MYSELF INCLUDED) AND OUR MOST TRUSTED MECHS ALL BELIEVE THAT THE NEXT TIME A DOOR COMES OFF THIS TYPE LTT IT COULD PROVE CATASTROPHIC. LOOKING BACK, I BELIEVE I DID THE PROPER THING WHEN I IMMEDIATELY TURNED BACK TOWARD THE ARPT. AT THAT INSTANT, I DID NOT KNOW IF IT WAS AN INDICATION PROB OR IF THE DOOR WAS GOING TO OPEN. THE PROB TURNED OUT TO BE AN INDICATION PROB WHICH I CONTRIBUTE TO POOR PREVENTATIVE MAINT, LACK OF THE PROPER NUMBER OF MECHS TO WORK ON THESE ACFT DURING THE FEW, SHORT NIGHT TIME HRS THAT ARE AVAILABLE.

Data retrieved from NASA's ASRS site as of August 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.