Accident Overview
On May 1, 2018, at about 1709 Pacific daylight time, a Robinson R-22 Beta II helicopter, registration N7526S, sustained substantial damage in an accident near Scappoose/Sauvie Island, Oregon. The commercial pilot, who was the sole occupant, was seriously injured. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a personal flight.
Flight Tracking and Witnesses
According to Federal Aviation Administration (FAA) radar and communications data, shortly after takeoff the pilot contacted air traffic control and requested visual flight rules (VFR) flight following while at an altitude of about 1,400 ft mean sea level and a ground speed of 70 knots. Approximately twenty minutes later, the pilot cancelled flight following, and radar contact was lost soon after. The pilot did not provide a statement about the accident, and no witnesses were identified.
Wreckage Examination
An FAA inspector responded to the accident site and found the wreckage in an open, level, grassy field. There was no evidence of a post-crash fire. The helicopter came to rest upright with both main and tail rotor blades still attached to their hubs. One tail rotor blade was intact; the other was bent at midspan. The main rotor blades were mostly intact and displayed only minor impact damage. The throttle linkage control integrity was confirmed, with the throttle control arm in the open position at the carburetor and the mixture control set to full rich.
Post-Recovery Evaluation
Following recovery, control continuity was verified from the cockpit through the flight control systems to both the main and tail rotors. Manual rotation of the clutch shaft produced corresponding rotation of the main rotor hub. Both main rotor blades appeared bent down approximately 20 degrees. The tail rotor drive shaft was straight with no signs of bending, twisting, or binding. The oil dipstick indicated about 6 quarts of oil. Approximately 3 gallons of fuel were drained from the main tank, and some fuel was drained from the auxiliary tank sump. The fuel bowl was clean, and no particles were observed in the filter. The spark plugs were removed and exhibited normal operating signatures. The rocker box covers were removed, and the engine was rotated manually, confirming valve and drive train continuity throughout the engine. The right magneto had become impact-separated from the engine, while the left magneto remained attached. Both magnetos produced spark when rotated. The oil screen was free of obstructions.