20080614839729A

Accident · Substantial damage

FAA accident report · Robsin R44RAVENII · Topangna, CA · June 14, 2008

Date: June 14, 2008 · 19:14 local
Place: Topangna, CA
Phase of flight: Fcd/Prec Ldg From Cruise
Operating rules: General operating rules (Part 91)
Damage: Substantial damage
Aircraft: N168AG
NTSB investigation: NTSBLAX08LA183
Reported as: Robsin R44RAVENII
Reported engine: Lycoming O540*
Fatal injuries: 0
Pilot’s flight hours: 6,028 total100 in this make and model65 in the last 90 days

N168AGRegistration cancelled Apr 30, 2015 · Robinson Helicopter R44 IIS/N 10938 · Built 2005 Airframe modelRobinson Helicopter R44 II Engine modelLycoming IO-540 seriesReciprocating

From the FAA’s Accident/Incident Data System (AIDS), through its Aviation Safety Information Portal, as reported. The NTSB investigates accidents separately, and its record of an accident is the fuller one. The aircraft is matched to the registry by N-number and event date, checked against the reported make and model; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

What happened

The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.

(-23) On 06/14/2008 while in cruise flight with 20 inches of manifold, 80 to 90 knots airspeed, at 2500 feet above sea level. The pilot heard a loud bang whicy was immediately followed with the helicopter yawing to the right 30 to 50 degrees and main rotor RPM decreasing. The pilot initiated a 180 degree turning auto rotation to a trail on topanga canyon. At the end of the auto rotation flare the pilot pulled up a little collective to cushion, the helicopter yawed to the right at touch down. The left landing gear skid assembly folded up. The helicopter rolled on to its right side and slid down the slope and came to rest 15 feet from touch down point. The tail rotor attachment fitting came to rest 75 feet down the embankment from the helicopter. The tail rotor blades were found approximately 1/2 mile north of the crash site. The tail rotor hub assembly and 90 degree gear box is missing, and has not been found yet.

As the FAA filed it

(-23) ON 06/14/2008 WHILE IN CRUISE FLIGHT WITH 20 INCHES OF MANIFOLD, 80 TO 90 KNOTS AIRSPEED, AT 2500 FEET ABOVE SEA LEVEL. THE PILOT HEARD A LOUD BANG WHICY WAS IMMEDIATELY FOLLOWED WITH THE HELICOPTER YAWING TO THE RIGHT 30 TO 50 DEGREES AND MAIN ROTOR RPM DECREASING. THE PILOT INITIATED A 180 DEGREE TURNING AUTO ROTATION TO A TRAIL ON TOPANGA CANYON. AT THE END OF THE AUTO ROTATION FLARE THE PILOT PULLED UP A LITTLE COLLECTIVE TO CUSHION, THE HELICOPTER YAWED TO THE RIGHT AT TOUCH DOWN. THE LEFT LANDING GEAR SKID ASSEMBLY FOLDED UP. THE HELICOPTER ROLLED ON TO ITS RIGHT SIDE AND SLID DOWN THE SLOPE AND CAME TO REST 15 FEET FROM TOUCH DOWN POINT. THE TAIL ROTOR ATTACHMENT FITTING CAME TO REST 75 FEET DOWN THE EMBANKMENT FROM THE HELICOPTER. THE TAIL ROTOR BLADES WERE FOUND APPROXIMATELY 1/2 MILE NORTH OF THE CRASH SITE. THE TAIL ROTOR HUB ASSEMBLY AND 90 DEGREE GEAR BOX IS MISSING, AND HAS NOT BEEN FOUND YET.

NTSB investigation

The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.

NTSB LAX08LA183Accident · Minor injuriesLimited investigationFinal reportTopanga, CAThe in-flight separation of the tail rotor gear box for an undetermined reason. Contributing to the accident was the hilly terrain, which was unsuitable for a forced landing.Jun 15, 2008 · Substantial damage