What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(-23) On July 14, 2005, at approximately 0810 CST, an MBB-BK117-B2 helicopter serial number 7238, registered as N440HH, was being operated by hermann life flight, a 14 CFR 135 air ambulance operator (gvna) was landing at the pearland regional airport (klvj) using runway 14L. This was the terminating point for the 14 CFR 91 repositioning flight when the left-side sliding door departed the aircraft and impacted the main rotor system. The pilot and cabin crew all reported that at approximately 100 feet AGL and 55 knots the pilot told the cabin crew that it was ok to open the side doors in preparation for landing. The left-side flight nurse stated that he had just unlatched the side door when the bottom flew upward and the door departed the aircraft. The flight crew all reported a loud bang and the aircraft shuttered, the pilot then landed the aircraft without further incident. Inspection of the aircraft showed that all four main rotor blades had substantial damage and that the left-side door had been destroyed. Parts of the door (approximately 90%) were recovered from an area about 75 feet in diameter in the center of runway 14L approximately 100 feet from the approach end. The top latches were in good condition and the emergency evacuation pins were also in good condition. The top rail of the aircraft's slide for the left-side door slide had damage where the door had pulled away with an upward movement and the bottom did not show damage but had significant wear in the aircraft and door rails and runners. The lower aircraft's door rail was inspected further and it was noted that at the point where the aft runner contacts the rail with the door latched was worn to a thickness of .035 from an original dimension of .050 thick. The runner was also worn and was .010 thinner at the top than the bottom. The rotorcraft directorate in ft worth was notified along with the NTSB and the manufacturer as it was also found that on may 25, 2005, that a BK117 in st louis, Missouri, had the same type of occurrence as the left-side door came off in flight. The operator has stopped the practice of opening the side doors in-flight until a fix or change can be found.
As the FAA filed it
(-23) ON JULY 14, 2005, AT APPROXIMATELY 0810 CST, AN MBB-BK117-B2 HELICOPTER SERIAL NUMBER 7238, REGISTERED AS N440HH, WAS BEING OPERATED BY HERMANN LIFE FLIGHT, A 14 CFR 135 AIR AMBULANCE OPERATOR (GVNA) WAS LANDING AT THE PEARLAND REGIONAL AIRPORT (KLVJ) USING RUNWAY 14L. THIS WAS THE TERMINATING POINT FOR THE 14 CFR 91 REPOSITIONING FLIGHT WHEN THE LEFT-SIDE SLIDING DOOR DEPARTED THE AIRCRAFT AND IMPACTED THE MAIN ROTOR SYSTEM. THE PILOT AND CABIN CREW ALL REPORTED THAT AT APPROXIMATELY 100 FEET AGL AND 55 KNOTS THE PILOT TOLD THE CABIN CREW THAT IT WAS OK TO OPEN THE SIDE DOORS IN PREPARATION FOR LANDING. THE LEFT-SIDE FLIGHT NURSE STATED THAT HE HAD JUST UNLATCHED THE SIDE DOOR WHEN THE BOTTOM FLEW UPWARD AND THE DOOR DEPARTED THE AIRCRAFT. THE FLIGHT CREW ALL REPORTED A LOUD BANG AND THE AIRCRAFT SHUTTERED, THE PILOT THEN LANDED THE AIRCRAFT WITHOUT FURTHER INCIDENT. INSPECTION OF THE AIRCRAFT SHOWED THAT ALL FOUR MAIN ROTOR BLADES HAD SUBSTANTIAL DAMAGE AND THAT THE LEFT-SIDE DOOR HAD BEEN DESTROYED. PARTS OF THE DOOR (APPROXIMATELY 90%) WERE RECOVERED FROM AN AREA ABOUT 75 FEET IN DIAMETER IN THE CENTER OF RUNWAY 14L APPROXIMATELY 100 FEET FROM THE APPROACH END. THE TOP LATCHES WERE IN GOOD CONDITION AND THE EMERGENCY EVACUATION PINS WERE ALSO IN GOOD CONDITION. THE TOP RAIL OF THE AIRCRAFT'S SLIDE FOR THE LEFT-SIDE DOOR SLIDE HAD DAMAGE WHERE THE DOOR HAD PULLED AWAY WITH AN UPWARD MOVEMENT AND THE BOTTOM DID NOT SHOW DAMAGE BUT HAD SIGNIFICANT WEAR IN THE AIRCRAFT AND DOOR RAILS AND RUNNERS. THE LOWER AIRCRAFT'S DOOR RAIL WAS INSPECTED FURTHER AND IT WAS NOTED THAT AT THE POINT WHERE THE AFT RUNNER CONTACTS THE RAIL WITH THE DOOR LATCHED WAS WORN TO A THICKNESS OF .035 FROM AN ORIGINAL DIMENSION OF .050 THICK. THE RUNNER WAS ALSO WORN AND WAS .010 THINNER AT THE TOP THAN THE BOTTOM. THE ROTORCRAFT DIRECTORATE IN FT WORTH WAS NOTIFIED ALONG WITH THE NTSB AND THE MANUFACTURER AS IT WAS ALSO FOUND THAT ON MAY 25, 2005, THAT A BK117 IN ST LOUIS, MISSOURI, HAD THE SAME TYPE OF OCCURRENCE AS THE LEFT-SIDE DOOR CAME OFF IN FLIGHT. THE OPERATOR HAS STOPPED THE PRACTICE OF OPENING THE SIDE DOORS IN-FLIGHT UNTIL A FIX OR CHANGE CAN BE FOUND.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.