What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
At approximately 1210 MST, the commercial pilot had been at work approximately three and one half hours before the accident. The pilot stated he had finished the main chemical application of the field and was repositioning to southern end to ?touch up? Missed areas indicated by the GPS. After repositioning, the pilot turned from southbound to northbound, and descended from approximately 100 feet above ground level (AGL) to 8 feet AGL at 45 knots indicated airspeed in preparation for a chemical application pass. While leveling off at 8 feet, the pilot felt the helicopter ?pushed down? And immediately impacted the ground. Examination of the GPS indicated the helicopter was traveling at 73 knots ground speed at impact. The differential between GPS groundspeed (73 knots) and indicated airspeed (45 knots) indicates a potential 28 knot downwind condition during the moments leading to impact. The pilot stated he was rushing to finish the job.
The 1158 MST weather observation at luke afb indicated clear skies with 10 miles visibility, winds from 170 degrees at 11 knots with no gusts. The temperature was 40 degrees celsius, dew point was 4.7 degrees celsius, and the altimeter setting was 29.81 in hg, resulting in a density altitude of approximately 4115 feet. The 1258 MST luke afb observation was similar in all aspects except the wind was from 200 degrees at 10 knots gusting up to 20. The pilot reported easterly winds at 5 to 8 knots with no gusts.
The impact signature trail is offset approximately 15 degrees right (015 degrees) of the north to south field orientation. The right skid tube impacted and slid along a metal irrigation tube in place on the ground from north to south. Approximately 20 feet further north the left skid tube impacted the ground causing both forward and aft cross tubes to fail, and the aircraft nose to impact the ground, causing the helicopter to flip over. Multiple main rotor impacts with the ground caused several breaks in the main rotor blades and the main rotor hub to separate from the mast. The tail boom buckled down and slightly right just forward of the horizontal stabilizer assembly. The tail rotor hub assembly remained attached to the tail rotor gearbox. The helicopter came to rest on its right side pointing approximately west. The pilot sustained serious injuries. There were no mechanical irregularities reported by the pilot or discovered post accident.
As the FAA filed it
AT APPROXIMATELY 1210 MST, THE COMMERCIAL PILOT HAD BEEN AT WORK APPROXIMATELY THREE AND ONE HALF HOURS BEFORE THE ACCIDENT. THE PILOT STATED HE HAD FINISHED THE MAIN CHEMICAL APPLICATION OF THE FIELD AND WAS REPOSITIONING TO SOUTHERN END TO ?TOUCH UP? MISSED AREAS INDICATED BY THE GPS. AFTER REPOSITIONING, THE PILOT TURNED FROM SOUTHBOUND TO NORTHBOUND, AND DESCENDED FROM APPROXIMATELY 100 FEET ABOVE GROUND LEVEL (AGL) TO 8 FEET AGL AT 45 KNOTS INDICATED AIRSPEED IN PREPARATION FOR A CHEMICAL APPLICATION PASS. WHILE LEVELING OFF AT 8 FEET, THE PILOT FELT THE HELICOPTER ?PUSHED DOWN? AND IMMEDIATELY IMPACTED THE GROUND. EXAMINATION OF THE GPS INDICATED THE HELICOPTER WAS TRAVELING AT 73 KNOTS GROUND SPEED AT IMPACT. THE DIFFERENTIAL BETWEEN GPS GROUNDSPEED (73 KNOTS) AND INDICATED AIRSPEED (45 KNOTS) INDICATES A POTENTIAL 28 KNOT DOWNWIND CONDITION DURING THE MOMENTS LEADING TO IMPACT. THE PILOT STATED HE WAS RUSHING TO FINISH THE JOB.
THE 1158 MST WEATHER OBSERVATION AT LUKE AFB INDICATED CLEAR SKIES WITH 10 MILES VISIBILITY, WINDS FROM 170 DEGREES AT 11 KNOTS WITH NO GUSTS. THE TEMPERATURE WAS 40 DEGREES CELSIUS, DEW POINT WAS 4.7 DEGREES CELSIUS, AND THE ALTIMETER SETTING WAS 29.81 IN HG, RESULTING IN A DENSITY ALTITUDE OF APPROXIMATELY 4115 FEET. THE 1258 MST LUKE AFB OBSERVATION WAS SIMILAR IN ALL ASPECTS EXCEPT THE WIND WAS FROM 200 DEGREES AT 10 KNOTS GUSTING UP TO 20. THE PILOT REPORTED EASTERLY WINDS AT 5 TO 8 KNOTS WITH NO GUSTS.
THE IMPACT SIGNATURE TRAIL IS OFFSET APPROXIMATELY 15 DEGREES RIGHT (015 DEGREES) OF THE NORTH TO SOUTH FIELD ORIENTATION. THE RIGHT SKID TUBE IMPACTED AND SLID ALONG A METAL IRRIGATION TUBE IN PLACE ON THE GROUND FROM NORTH TO SOUTH. APPROXIMATELY 20 FEET FURTHER NORTH THE LEFT SKID TUBE IMPACTED THE GROUND CAUSING BOTH FORWARD AND AFT CROSS TUBES TO FAIL, AND THE AIRCRAFT NOSE TO IMPACT THE GROUND, CAUSING THE HELICOPTER TO FLIP OVER. MULTIPLE MAIN ROTOR IMPACTS WITH THE GROUND CAUSED SEVERAL BREAKS IN THE MAIN ROTOR BLADES AND THE MAIN ROTOR HUB TO SEPARATE FROM THE MAST. THE TAIL BOOM BUCKLED DOWN AND SLIGHTLY RIGHT JUST FORWARD OF THE HORIZONTAL STABILIZER ASSEMBLY. THE TAIL ROTOR HUB ASSEMBLY REMAINED ATTACHED TO THE TAIL ROTOR GEARBOX. THE HELICOPTER CAME TO REST ON ITS RIGHT SIDE POINTING APPROXIMATELY WEST. THE PILOT SUSTAINED SERIOUS INJURIES. THERE WERE NO MECHANICAL IRREGULARITIES REPORTED BY THE PILOT OR DISCOVERED POST ACCIDENT.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.