NTSB Factual Report

On May 27, 2011, about 1800 central daylight time, a Bell OH-58C, N82772, operated by the Bay County (Florida) Sheriff's Office, was substantially damaged while hover-taxiing out of a hangar at a recently-closed airport in Panama City, Florida. The certificated commercial pilot and the observer incurred minor injuries. Visual meteorological conditions prevailed. No flight plan had been filed for the local flight, from the former Panama City-Bay County International Airport (PFN), Panama City, Florida. The public use flight was departing on an aerial observation mission.

According to a Federal Aviation Administration (FAA) inspector, the helicopter was one of two sheriff's department helicopters that were temporarily housed in the old hangar, and ground support equipment, including wheel dollies, had been moved to the unit's new location at a new airport. The helicopter had flown in and out of the hangar on numerous occasions, and a photograph of the accident scene showed an open-ended hangar with the accident helicopter at one end, and a similar helicopter parked inside, at the other end.

According to the pilot, he was hover taxiing the helicopter straight out of the hangar about 3 feet above the ground. When the helicopter was almost out, except for possibly the last few feet, the pilot heard a loud bang. He started lowering the collective to land, but the helicopter began rotating and he had no control. The helicopter ended up on its left side, facing 180 degrees from the original direction of flight.

The onboard observer stated that while the helicopter was exiting the hangar, and was mostly out or had just cleared it, she heard a "loud thud" from what sounded like something striking the top of the helicopter. She started to turn toward the pilot when the helicopter began abruptly rotating, then impacted the ground on its left side. The observer confirmed that the helicopter had been taxiing straight out at the time at what she considered was a lower than normal taxi height.

The accident scene resided in the geographical area of the Birmingham Flight Standards District Office (FSDO). The FSDO did not respond to the accident scene.

Photographs were provided by the Bay County Sheriff's Office. Photographs indicated that the helicopter came to rest on its left side, with the main rotor blades separated from the rotor head and impact-damaged. The tail boom was twisted about 120 degrees, almost upside down, and the tail rotor drive shaft within the boom was separated. An additional photograph provided by the pilot showed rotational scoring of the tail rotor drive shaft aft of the separation point.

Several photographs also showed the bottom side of the overhead hangar door frame, a horizontal steel I-beam with the underside, outside corner covered by a lip of heavy aluminum. Remnants of electrical conduit, which normally would have been secured above the hangar door frame, were also present. However, some of the conduit was drooped below the I-beam, and appeared to have been separated and coiled in the vicinity of hangar door frame damage.

The photographs also revealed several sets of scrape marks, all relatively narrow, on the underside of the I-beam. The first set of marks was an estimated 2 to 3 feet to the right of the hangar door center. Another set of scrape marks was an estimated 2 to 3 feet right of the first marks, again on the underside of the I-beam, with the aluminum doorframe lip deformed slightly upward. A third set of marks, about 3 to 4 feet right of the second set, had scraping at the inside, underside edge of the I-beam that disappeared, then reappeared where the outside aluminum lip was torn downward.

The order in which the sets of marks were made could not be determined. None of the sets was perpendicular to the I-beam; the first set noted was angled about 30 degrees to the right, while the other two sets noted were angled 20 to 25 degrees to the left.

Other photographs showed the vertical fin and the tail rotor blades. The top of the vertical fin, which extended above the rotational plane of the tail rotor blades, exhibited scraping. The leading edge of the vertical fin also exhibited scraping, along with an almost horizontal line several inches from the top of the fin. The tail rotor blades were pristine.

The pilot also noted that the old hangar had been vandalized, with vandals having removed conduit from several areas. He did not note any preexisting mechanical anomalies with the helicopter, and when asked to turn the tail rotor to ensure continuity through the 90-degree and intermediate gear boxes, he reported that everything appeared to turn normally.

NTSB Probable Cause

The drooping electrical conduit, which snagged the vertical fin and resulted in the pilot's inability to control the helicopter. Contributing to the accident was the operator's decision to have the pilot fly the helicopter out of the hangar.