Accident Narrative
On May 2, 2018, about 1000 central daylight time, a Robinson R-22 Mariner helicopter, registration N923SM, operated by N923SM LLC, was substantially damaged during a forced landing near Panama City Beach, Florida. The commercial pilot received minor injuries. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a positioning flight. Visual meteorological conditions prevailed, and no flight plan was filed. The helicopter departed Perry-Foley Airport (40J) in Perry, Florida, at 0830, destined for Destin Executive Airport (DTS) in Destin, Florida.
The pilot reported that about 90 minutes after departure, while cruising at 80 knots and 800 feet mean sea level, the helicopter slowly lost airspeed. He pushed the cyclic forward, but airspeed continued to decrease and altitude was lost. The cyclic reached its forward stop, and the pilot realized he had no cyclic authority. The helicopter continued descending with nearly zero forward airspeed and little flare, impacting the water. The helicopter floated briefly until waves struck its side, causing it to invert.
A coworker flying in formation at about 700 feet mean sea level observed the accident helicopter decelerate from 80 knots to 30 knots in about 15 seconds. He reported that the helicopter descended in a reverse gliding attitude and struck the water tail boom first before rolling upside down.
Investigation Findings
Prior to the flight, the pilot removed blade tie-down ropes and associated blade tip socks during preflight inspection. He thought he placed the ropes under the left cockpit seat storage container. The flight was conducted with the cockpit doors removed.
Ground witnesses from the United States Coast Guard and a salvage company reported that the tie-down ropes used for the rotor blades were found wrapped around the rotor head assembly, swash plate, and pitch control rods. The ropes remained in place when the recovery team arrived.
Examination by a Federal Aviation Administration inspector revealed that the main rotor blades were deformed, the fuselage was substantially damaged, and the tail boom was partially separated. A tiedown rope and blade sock were tightly wrapped around the swash plate and pitch change links of the main rotor.
The pilot held a commercial pilot certificate with rotorcraft-helicopter rating and a flight instructor certificate for rotorcraft-helicopter. He reported 467.7 total flight hours, all in the accident helicopter make and model, with about 50 hours in the previous 90 days and 20 hours in the previous 30 days.
The helicopter, serial number 1923M, was manufactured in 1991 and issued a standard airworthiness certificate. It was equipped with floats and powered by a 160-horsepower Lycoming O-320-B2C engine. As of the most recent annual inspection on December 28, 2017, the engine had 4,988.6 hours total time and the airframe had 6,988.7 hours. The airframe and engine logbooks were on board at the time of the accident and were lost.
Weather recorded at 0953 at Northwest Florida Beaches International Airport (ECP), about 12 miles north of the accident site, included no clouds, visibility of 10 statute miles, wind from 140° true at 9 knots, temperature 20°C, dew point 18°C, and altimeter setting 30.27 inches of mercury.