What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
Schempp-hirth nimbus 4DM glider crashed under unknown circumstances and was destroyed, the 2 POB (including a former FAA administrator) suffered fatal injuries, all other circumstances are unknown at this time. (.19)on July 13, 1999, at 1310 hours pacific daylight time, a schempp-hirth nimbus 4DM motorized glider, N807BB, experienced an in-flight breakup while maneuvering near Minden, Nevada. The commercial glider pilot and a passenger were fatally injuried and the glider was destroyed. The personal flight was operated by the owner/pilot under the provisions of 14 CFR part 91. No flight plan was filed for the local flight. The glider in germany, a standard/utility category airworthiness certificate was issued by the german civil aviation authority. The glider departed for Minden airport at 1240. A glider pilot witness stated he was soaring about 1,000 feet below the accident. Glider. The witness observed the glider in a high-speed spiral with a 45-degree nose down attitude. After two full rotations, the rotation stopped the flight stabilized on a north easterly heading, and the nose ptiched further down to a near vertical attitude. The glider was observed to level its attitude, with the wings bending upward and the wing tips coning higher. The outboard wing tip panels departed from the glider, the wings disintegrated, and the fuselage dove into the ground. Other witnesses have subsequently stated the glider was in a tight turn, as if climbing in a thermal, when it entered the spiral. The glider appeared to be recovering from a spin. A second witness was in another glider between 9,000 to 10,000 feet and observed portions of the accident sequence. He immediately headed for the airport to report the accident and encountered "very turbulent" conditions with a sudden 40-knot airspeed increase. He characterized the conditions as "more choppy than normal" and further stated that "controllability was not unmanageable but was rough." The glider is composite construction. Reconstruction of the glider revealed that all primary and secondary flight control surfaces, including mass balance weights, were within the wreckage distribution path. Control system continuity was established. (-23)witnesses report the accident aircraft was observe working a-thermal. Loss of control apparently occurred for unknown reasons. Acft was seen co mpleting two rolls in steed nose down attitude. Rolling stopped, recovery pull-up began, wing failed during a pull-up attempt. Acft struck terrain at about 5,000' elevation.
As the FAA filed it
SCHEMPP-HIRTH NIMBUS 4DM GLIDER CRASHED UNDER UNKNOWN CIRCUMSTANCES AND WAS DESTROYED, THE 2 POB (INCLUDING A FORMER FAA ADMINISTRATOR) SUFFERED FATAL INJURIES, ALL OTHER CIRCUMSTANCES ARE UNKNOWN AT THIS TIME. (.19)ON JULY 13, 1999, AT 1310 HOURS PACIFIC DAYLIGHT TIME, A SCHEMPP-HIRTH NIMBUS 4DM MOTORIZED GLIDER, N807BB, EXPERIENCED AN IN-FLIGHT BREAKUP WHILE MANEUVERING NEAR MINDEN, NEVADA. THE COMMERCIAL GLIDER PILOT AND A PASSENGER WERE FATALLY INJURIED AND THE GLIDER WAS DESTROYED. THE PERSONAL FLIGHT WAS OPERATED BY THE OWNER/PILOT UNDER THE PROVISIONS OF 14 CFR PART 91. NO FLIGHT PLAN WAS FILED FOR THE LOCAL FLIGHT. THE GLIDER IN GERMANY, A STANDARD/UTILITY CATEGORY AIRWORTHINESS CERTIFICATE WAS ISSUED BY THE GERMAN CIVIL AVIATION AUTHORITY. THE GLIDER DEPARTED FOR MINDEN AIRPORT AT 1240. A GLIDER PILOT WITNESS STATED HE WAS SOARING ABOUT 1,000 FEET BELOW THE ACCIDENT. GLIDER. THE WITNESS OBSERVED THE GLIDER IN A HIGH-SPEED SPIRAL WITH A 45-DEGREE NOSE DOWN ATTITUDE. AFTER TWO FULL ROTATIONS, THE ROTATION STOPPED THE FLIGHT STABILIZED ON A NORTH EASTERLY HEADING, AND THE NOSE PTICHED FURTHER DOWN TO A NEAR VERTICAL ATTITUDE. THE GLIDER WAS OBSERVED TO LEVEL ITS ATTITUDE, WITH THE WINGS BENDING UPWARD AND THE WING TIPS CONING HIGHER. THE OUTBOARD WING TIP PANELS DEPARTED FROM THE GLIDER, THE WINGS DISINTEGRATED, AND THE FUSELAGE DOVE INTO THE GROUND. OTHER WITNESSES HAVE SUBSEQUENTLY STATED THE GLIDER WAS IN A TIGHT TURN, AS IF CLIMBING IN A THERMAL, WHEN IT ENTERED THE SPIRAL. THE GLIDER APPEARED TO BE RECOVERING FROM A SPIN. A SECOND WITNESS WAS IN ANOTHER GLIDER BETWEEN 9,000 TO 10,000 FEET AND OBSERVED PORTIONS OF THE ACCIDENT SEQUENCE. HE IMMEDIATELY HEADED FOR THE AIRPORT TO REPORT THE ACCIDENT AND ENCOUNTERED "VERY TURBULENT" CONDITIONS WITH A SUDDEN 40-KNOT AIRSPEED INCREASE. HE CHARACTERIZED THE CONDITIONS AS "MORE CHOPPY THAN NORMAL" AND FURTHER STATED THAT "CONTROLLABILITY WAS NOT UNMANAGEABLE BUT WAS ROUGH." THE GLIDER IS COMPOSITE CONSTRUCTION. RECONSTRUCTION OF THE GLIDER REVEALED THAT ALL PRIMARY AND SECONDARY FLIGHT CONTROL SURFACES, INCLUDING MASS BALANCE WEIGHTS, WERE WITHIN THE WRECKAGE DISTRIBUTION PATH. CONTROL SYSTEM CONTINUITY WAS ESTABLISHED. (-23)WITNESSES REPORT THE ACCIDENT AIRCRAFT WAS OBSERVE WORKING A-THERMAL. LOSS OF CONTROL APPARENTLY OCCURRED FOR UNKNOWN REASONS. ACFT WAS SEEN CO MPLETING TWO ROLLS IN STEED NOSE DOWN ATTITUDE. ROLLING STOPPED, RECOVERY PULL-UP BEGAN, WING FAILED DURING A PULL-UP ATTEMPT. ACFT STRUCK TERRAIN AT ABOUT 5,000' ELEVATION.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.