Narrative:

I was scheduled to fly as an first officer on a trip in an astra (iai 1125). My passenger arrived at the airport and I took them to the aircraft. The captain started the #2 engine as the passenger boarded and I closed the main cabin door and latched it. I felt a small pressurization bump and told the captain; 'door closed and secured.' I got into the left seat to fly the aircraft and the captain and I finished the checklists. We then called for taxi and proceeded to taxi to runway 24. There were no anomalies and all lights on the annunciator panel were extinguished or normal. We were cleared to takeoff and did so. Everything was normal until 1000 ft AGL when the main cabin door came fully open. We declared an emergency and immediately returned to ZZZ. We shot an ILS to runway 24 after completing our checklists and landed the aircraft with the cabin door open. I brought the aircraft to a stop on the runway; set the parking brake; shut down the engines; and evacuated the passenger. No one was injured and we had the aircraft towed off the runway to a secure area. Callback conversation with reporter revealed the following information: reporter emphasized that the cabin door was properly closed and that subsequent to the landing; he was able to reclose it; again apparently properly secured. He indicated the door is not a plug type but depends on mechanical pins and slots for security. The door has been removed and returned to the manufacturer for repair and refitting. Reporter indicated that this was an early version of the astra and that he was aware of another failure on an early model prior to this event. He stated the door warning light indicated both an improperly secured door and inadequate pneumatic pressure to the inflatable pressure seal. He felt there was some tendency to be casual about this light because it would sometimes illuminate at low throttle settings due to the pneumatic nature of the seal; extinguishing when more thrust was employed. He emphasized; however; that in his incident the light was never illuminated. Reporter was concerned that this very complex closure system is only required to be inspected at 1000 hour intervals which can be years apart in the standard operation of this class of airplane. The aircraft in question was built in 1988.

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Original NASA ASRS Text

Title: SHORTLY AFTER TKOF THE CABIN DOOR ON AN ASTRA OPENS COMPLETELY. RPTR STATES DOOR WAS PROPERLY SECURED AND NO WARNING LIGHTS WERE DISPLAYED.

Narrative: I WAS SCHEDULED TO FLY AS AN FO ON A TRIP IN AN ASTRA (IAI 1125). MY PAX ARRIVED AT THE ARPT AND I TOOK THEM TO THE ACFT. THE CAPT STARTED THE #2 ENG AS THE PAX BOARDED AND I CLOSED THE MAIN CABIN DOOR AND LATCHED IT. I FELT A SMALL PRESSURIZATION BUMP AND TOLD THE CAPT; 'DOOR CLOSED AND SECURED.' I GOT INTO THE L SEAT TO FLY THE ACFT AND THE CAPT AND I FINISHED THE CHKLISTS. WE THEN CALLED FOR TAXI AND PROCEEDED TO TAXI TO RWY 24. THERE WERE NO ANOMALIES AND ALL LIGHTS ON THE ANNUNCIATOR PANEL WERE EXTINGUISHED OR NORMAL. WE WERE CLRED TO TKOF AND DID SO. EVERYTHING WAS NORMAL UNTIL 1000 FT AGL WHEN THE MAIN CABIN DOOR CAME FULLY OPEN. WE DECLARED AN EMER AND IMMEDIATELY RETURNED TO ZZZ. WE SHOT AN ILS TO RWY 24 AFTER COMPLETING OUR CHKLISTS AND LANDED THE ACFT WITH THE CABIN DOOR OPEN. I BROUGHT THE ACFT TO A STOP ON THE RWY; SET THE PARKING BRAKE; SHUT DOWN THE ENGS; AND EVACUATED THE PAX. NO ONE WAS INJURED AND WE HAD THE ACFT TOWED OFF THE RWY TO A SECURE AREA. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR EMPHASIZED THAT THE CABIN DOOR WAS PROPERLY CLOSED AND THAT SUBSEQUENT TO THE LNDG; HE WAS ABLE TO RECLOSE IT; AGAIN APPARENTLY PROPERLY SECURED. HE INDICATED THE DOOR IS NOT A PLUG TYPE BUT DEPENDS ON MECHANICAL PINS AND SLOTS FOR SECURITY. THE DOOR HAS BEEN REMOVED AND RETURNED TO THE MANUFACTURER FOR REPAIR AND REFITTING. RPTR INDICATED THAT THIS WAS AN EARLY VERSION OF THE ASTRA AND THAT HE WAS AWARE OF ANOTHER FAILURE ON AN EARLY MODEL PRIOR TO THIS EVENT. HE STATED THE DOOR WARNING LIGHT INDICATED BOTH AN IMPROPERLY SECURED DOOR AND INADEQUATE PNEUMATIC PRESSURE TO THE INFLATABLE PRESSURE SEAL. HE FELT THERE WAS SOME TENDENCY TO BE CASUAL ABOUT THIS LIGHT BECAUSE IT WOULD SOMETIMES ILLUMINATE AT LOW THROTTLE SETTINGS DUE TO THE PNEUMATIC NATURE OF THE SEAL; EXTINGUISHING WHEN MORE THRUST WAS EMPLOYED. HE EMPHASIZED; HOWEVER; THAT IN HIS INCIDENT THE LIGHT WAS NEVER ILLUMINATED. RPTR WAS CONCERNED THAT THIS VERY COMPLEX CLOSURE SYSTEM IS ONLY REQUIRED TO BE INSPECTED AT 1000 HR INTERVALS WHICH CAN BE YEARS APART IN THE STANDARD OPERATION OF THIS CLASS OF AIRPLANE. THE ACFT IN QUESTION WAS BUILT IN 1988.

Data retrieved from NASA's ASRS site as of January 2009 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.