N3101H

HISTORY OF FLIGHTOn April 3, 2013 about 1600 eastern daylight time, Robinson R44, N3101H, had components separate in flight and the helicopter impacted the ground shortly after takeoff from Kendall Tamiami Executive airport (TMB), Miami, Florida. The helicopter was registered to and operated by Bravo Helicopters, LLC, of Miami, Florida. The commercial pilot and pilot-rated mechanic incurred fatal injuries. The maintenance test flight was conducted under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the local flight that departed a few minutes before the accident.

Multiple witnesses in the vicinity of the crash site reported hearing a loud "pop" noise and seeing parts separate from the helicopter as the helicopter flew overhead. Witnesses were also consistent in reporting that the empennage section of the helicopter then departed the aircraft before impact with the ground. One witness, standing about 20 feet from the impact, stated that the helicopter was inverted over the industrial buildings before it impacted two palm trees about 25 feet above ground level, a pickup truck, and then the ground. Another witness stated that the postcrash fire started after the pilot and passenger were extracted from the helicopter or about 5 minutes after the initial impact. He also stated that the helicopter was inverted over the industrial buildings. PERSONNEL INFORMATIONAccording to Federal Aviation Administration (FAA) records, the pilot held a commercial pilot certificate with ratings for helicopter and airplane single-engine land, issued on October 23, 2003. The pilot was issued a mechanic certificate on October 23, 2003, with ratings for airframe and power plant. The pilot was issued a first-class medical certificate on February 25, 2013, with the medical restriction "must wear corrective lenses for distant and possess glasses for near vision." FAA records also indicated that in February of 2013, the pilot reported 6,840 total flight hours and 76 flight hours in the previous 6 months. The pilot's logbooks were not retrieved. AIRCRAFT INFORMATIONThe four-seat, skid-type landing gear helicopter, serial number 1610, was manufactured in 2006. The helicopter was powered by a Lycoming O-540-F1B5, 225 horsepower engine, serial number L-26556-40A. Review of the aircraft and engine logbooks revealed the last annual inspection was conducted on December 04, 2012 at an hour meter time of 749.4 total hours of operation. The hour meter was located at the crash site and read 760.2 hours. According to FAA records, the helicopter was issued a standard airworthiness certificate on October 21, 2011.

According to the helicopter logbook, the manufacturer's order form indicated that both spindle bearings were replaced, refurbished, and installed on the new rotor blades. When this was completed, the new rotor blades automatically incurred a reduced service life when installing used spindles. The remaining time on the new rotor blades was reduced from 2,200 hours or 12 years, whichever comes first, to match the used spindles which had about 1,439 hours or 5 years remaining, whichever came first. The rotor blades and spindles expire as a pair.

The mechanic was hired to conduct the re-installation of the main rotor blades on the helicopter on April 3, 2013. The course of the day was spent installing the blades, making adjustments to the pitch change links, and performing a track and balance procedure that adjusts the rotor blades for the smoothest operation on the rotor system. An approximate, uneventful 1 hour test flight was conducted prior to the accident flight. METEOROLOGICAL INFORMATIONThe TMB 1553 weather observation, located 1.5 miles west of the accident site, reported wind from 120 degrees at 12 knots, gusting to 18 knots, visibility 10 statute miles, scattered clouds at 3,000 feet above ground level, temperature 29 degrees Celsius, dew point 20 degrees Celsius, and an altimeter setting of 30.00 inches of mercury. AIRPORT INFORMATIONThe four-seat, skid-type landing gear helicopter, serial number 1610, was manufactured in 2006. The helicopter was powered by a Lycoming O-540-F1B5, 225 horsepower engine, serial number L-26556-40A. Review of the aircraft and engine logbooks revealed the last annual inspection was conducted on December 04, 2012 at an hour meter time of 749.4 total hours of operation. The hour meter was located at the crash site and read 760.2 hours. According to FAA records, the helicopter was issued a standard airworthiness certificate on October 21, 2011.

According to the helicopter logbook, the manufacturer's order form indicated that both spindle bearings were replaced, refurbished, and installed on the new rotor blades. When this was completed, the new rotor blades automatically incurred a reduced service life when installing used spindles. The remaining time on the new rotor blades was reduced from 2,200 hours or 12 years, whichever comes first, to match the used spindles which had about 1,439 hours or 5 years remaining, whichever came first. The rotor blades and spindles expire as a pair.

The mechanic was hired to conduct the re-installation of the main rotor blades on the helicopter on April 3, 2013. The course of the day was spent installing the blades, making adjustments to the pitch change links, and performing a track and balance procedure that adjusts the rotor blades for the smoothest operation on the rotor system. An approximate, uneventful 1 hour test flight was conducted prior to the accident flight. WRECKAGE AND IMPACT INFORMATIONThe helicopter was located upright in a parking lot on the corner of southwest 128th street and southwest 122nd avenue in Miami, Florida, and came to rest on a heading of 105 degrees magnetic (M). The debris field was 110 degrees at a distance of about 500 feet. A postcrash fire had consumed a majority of the wreckage. Several helicopter components were located on the roofs of several industrial buildings.

The red main rotor blade exhibited thermal damage about 7 feet from the hub outward towards the rotor tip, and the entire blade was upside down. The red main rotor blade data plate was missing and the alternate number was found on the inside of the tip cap as blade 3043. There was a paint scuff on the top surface of the spindle adjacent to the hub. There were impact marks on the hub from the pitch horn boot and impact marks from the pitch horn to the hub leading edge face with the leading edge, 60 degrees upward from normal orientation. The spindle was torn and there was deformation of the leading edge of the spindle bolt hole. There was a fracture from the leading edge aft, to 2.7 inches with the aft face having a journal impression. The pitch horn was fractured and deformed with impact marks immediately adjacent to the fracture surface. The pitch change link assembly remained attached to the pitch horn by the appropriate hardware. There was a torque stripe on one side of the pal nut. The rod end at the opposite end of the link assembly was unremarkable. The blade was cut 13 feet 7 inches inboard of the rotor tip for recovery. The spindle was connected and rotated roughly.

The blue main rotor blade exhibited thermal damage from the hub outward about 8 feet towards the rotor tip and the entire blade was bowed down. The data plate was found installed on the blade as number 3034. Blade delamination was consistent with thermal damage. There was impact damage 4 feet 6 inches, 6 feet 6 inches, and 10 feet 10 inches from the blade tip. The blade was cut 13 feet inboard of the rotor tip for recovery. The blade tip cover and weight was in place with no chord wise scoring noted from the tip inboard on the lower surface. There was compression wrinkles on the lower surface 1 foot 7 inches inboard from the rotor tip. The blade was displaced aft about the mid span and was bowed up 3 feet inboard from the tip. There was a compression wrinkle on the upper surface 6 feet 8 inches inboard from the rotor tip. The leading edge of the upper surface exhibited chord wise scratches from the tip inboard to 7 feet that corresponded to a ground scar in the asphalt at the crash site. The upper skin was delaminated from the root of the rotor to 9 feet outboard. Upward bending started 14 feet inboard of the blade tip. The spindle was connected and rotated roughly.

The upper swash plate fork remained connected to the swash plate. The yolk remained connected to the fork by the dog bone. The yolk was connected to the dog bone on both sides. The yolk was fractured on the weighted sides and was recovered from the roof top of a building. The weights were in place but damaged due to impact with the gravel roof of the industrial park building.

The tail boom exhibited a vertical scuff with white paint transfer 25.25 inches forward of the aft bulkhead, adjacent to the tail rotor blade tip arch. The intermediate flex coupling was deformed slightly, but still connected. There was rotational contact by the flex coupling with the upper frame. The tail cone was severed by the main rotor system between bays five and six during flight and came to rest 275 M about 300 feet from the initial impact point. The empennage remained attached to a 32-inch section of the tail boom, and exhibited damage to the trailing edge of the horizontal stabilizer. The tail rotor blades remained attached to the tail rotor gear box with one blade partially severed 9 inches outboard from the attachment point. The tail rotor rotated freely. There was fragmentation of bays five, six, and seven, at the left side where the danger sticker was adhered. This was consistent with a leading edge strike from a main rotor blade.

The tail rotor driveshaft was cut 8 inches aft of the flex coupling. The tail rotor gearbox rotated freely with no abnormal noise. Tail rotor flight control continuity was examined from the pedals to the tail rotor. Several separations wer...