History of Flight
On October 15, 2009, at approximately 1751 eastern daylight time, a Robinson R44 helicopter (N3038W) was substantially damaged during a forced landing near La Belle, Florida. The commercially-rated pilot and two passengers sustained minor injuries, and one passenger sustained a serious injury. The personal flight was conducted under Part 91 of the Federal Aviation Regulations. Visual meteorological conditions prevailed, and no flight plan was filed.
According to the pilot, the flight was a personal sightseeing trip with a friend and two acquaintances. He flew from the helicopter's base airport to a private farm in Punta Gorda, Florida, to pick up the passengers. The helicopter departed the farm about 1730. None of the helicopter's four doors were installed, and most of the flight was conducted at or below 300 feet above ground level (agl). After about 30 minutes, while in cruise flight at approximately 60 knots and 150 feet agl, the pilot heard a noise he described as a "light tapping" or a "thump," followed by an aural warning horn. He did not observe any other annunciations. The helicopter began to lose altitude, and the pilot initiated an autorotation toward a pasture. The tail struck trees, and the pilot reported losing anti-torque pedal control. He continued the autorotation to the ground.
Two passengers provided a different account. They stated that most of the flight was conducted "below tree top level" at a "slow" airspeed, and the flight was uneventful until the helicopter began to spin and descend. The front-seat passenger reported that the helicopter struck "something," after which the pilot briefly pulled up on the collective control and then pushed it down. Neither passenger noticed any warning horns or lights.
After ground impact, the helicopter spun approximately 180 degrees to the right and rolled onto its left side. The engine was not running; the pilot shut off the fuel and master switch. The pilot and two passengers exited; the remaining passenger, who seriously injured his foot, remained in the helicopter until assistance arrived. The pilot called 911 but could not effectively communicate the situation. He then called an acquaintance familiar with the area, who led law enforcement to the site. An EMS helicopter arrived approximately 2 hours after the accident and airlifted the injured passenger about 3 hours post-accident.
Personnel Information
FAA records showed the pilot held a commercial pilot certificate with a rotorcraft-helicopter rating and a private pilot certificate with an airplane single-engine land rating. His most recent FAA second-class medical certificate was issued in October 2009, and his last flight review was completed in June 2009. He had about 3,000 total flight hours, including approximately 900 hours in rotary-wing aircraft and 720 hours in the R44. About 4 months after this accident, the pilot was fatally injured while piloting another R44 in the Dominican Republic. The owner of N3038W was also fatally injured in that accident.
Aircraft Information
The helicopter was manufactured in 2007 and equipped with a Lycoming O-540 series piston engine. It was registered to a corporation. The pilot stated the owner allowed him to fly the helicopter for personal use. The most recent 100-hour inspection was completed in July 2009, and the helicopter had 720.8 total hours at the time of the accident. Maintenance records were not provided.
Meteorological Information
The 1753 recorded weather observation at Southwest Florida International Airport (RSW), Fort Myers, Florida, about 21 miles south-southwest of the accident site, included winds from 260 degrees at 8 knots, 10 miles visibility, few clouds at 3,500 feet, temperature 30°C, dew point 22°C, and altimeter setting 29.83 inches of mercury.
Wreckage and Impact Information
The helicopter came to rest in a grassy field bordered by a treeline, about 10.5 miles southeast of the flight's origination point. Substantial damage occurred to the tail boom, main rotor system, and fuselage. One tail rotor blade, the horizontal and vertical stabilizer tailplane assembly were fracture-separated. The tailplane assembly was found at the treeline about 120 feet from the helicopter. The left side of the fuselage was crumpled, main rotor blades bent, and main rotor mast deformed. Control rods and other main rotor control system components were bent or damaged. One drive belt was broken; the remaining three had come off at least one sheave. All drive belts exhibited frayed tie bands. The landing skids showed no significant deformation.
Additional Information
Global Positioning System (GPS) Data
The pilot's handheld Garmin GPS unit was operating during the accident flight. Data download revealed multiple flights, including the accident flight. GPS data indicated departure from Punta Gorda farm at about 1626 and the accident at about 1751, a total flight duration of about 90 minutes. The entire flight was conducted below 300 feet GPS altitude, most between 50 and 150 feet. The ground track was highly irregular and circuitous, with multiple turns, course reversals, and circuits of varying diameters (many less than 500 feet, some about 150 feet). Most of the flight was at ground speeds below 50 mph, averaging about 30 mph.
Telatemp Decals
The helicopter was equipped with heat-sensitive "Telatemp" decals factory-installed on critical components. The decals indicate temperature exposure by darkening squares irreversibly. The decal on the upper clutch actuator bearing had four black squares and one gray square, with a reference line to the left of the left-most square, indicating all six squares were initially white. The installed decal was part number "-3" (temperature range 180°F to 230°F), showing the component reached about 215°F. No indications of bearing distress or malfunction were noted.
Main Rotor RPM
The R44 Pilot Operating Handbook stated the helicopter had a single aural warning horn that activated when main rotor rpm dropped to 97% or less, and a low rotor rpm warning light that illuminated at the same threshold. The preflight checklist required verification of the horn and light before every flight. The warning unit received a signal from one of two Hall Effect transducers on the input yoke of the main rotor gearbox; the other transducer provided a signal to the rotor tachometer. The POH cautioned that installation of electrical devices could affect tachometers, low RPM warning system, and governor. The manufacturer defined "installed" as "set up for use or service," and stated that any electrical device present and operating in flight required explicit approval; all approved devices were console-mounted. Handheld GPS units were not approved, but no reports of interference had been received.
Drive Belts
Power transfer from the engine to the rotor system was via four flexible vee-belts linking engine and rotor sheaves. Each belt consisted of two V-shaped belts joined by a continuous tie-band. The upper sheave had an overrunning clutch. An electric actuator maintained belt tension. The manufacturer's representative stated that the damage signature on the tie bands was typical of belts displaced from sheave grooves. Displacement could occur from loose belts, abrupt maneuvering, or ground impact with the engine running. A failing drive belt can become loose, and displacement of one belt can affect others. When a drive belt starts to fail, it tends to make a repetitive thumping or tapping noise, and failure could result in low rotor rpm.