CEN20LA037

The student pilot and flight instructor completed an instructional flight, after which the instructor exited the helicopter to watch the student conduct a solo flight. The instructor explained to the student that the helicopter was going to "pick up" differently without his weight onboard, like the student's initial solo flight the day before, and the student "concurred and understood." The instructor watched the helicopter take off from the dry asphalt; however, the helicopter was "sliding back and right" as it took off. The right rear skid tube contacted the ground, the student did not correct for the ground contact, and the helicopter entered a dynamic rollover sequence. The main rotor blades impacted the ground, and the helicopter came to rest on its right side. The helicopter sustained substantial damage to the main rotor system, fuselage, tailboom, and empennage. The flight instructor reported that there were no preaccident mechanical failures or malfunctions with the airframe and engine that would have precluded normal operation. It is likely that the student applied improper cyclic input during the takeoff, which resulted in the right rear skid tube contacting the ground and a subsequent dynamic rollover.

On December 19, 2019, about 1510 central standard time, a Robinson R22 helicopter, impacted the ground during takeoff from the Beeville Municipal Airport (BEA), Beeville, Texas. The solo student pilot sustained no injury. The helicopter sustained substantial damage. The helicopter was registered to and operated by Prestige Air Worldwide, LLC, dba Ace High Helos, under the provisions of Title 14 Code of Federal Regulations Part 91 as an instructional flight. Day visual meteorological conditions prevailed at the time of the accident, and no flight plan was filed. The flight was intended to depart from and remain in the traffic pattern at BEA. The student pilot successfully conducted a solo flight in the same helicopter the day prior to the accident. The certificated flight instructor reported, that after three takeoffs, three landings, and various in ground effect hover work with the student pilot, the flight instructor felt comfortable with the student pilot to conduct another solo flight. The flight instructor exited the helicopter and positioned himself to watch the solo student pilot. As the flight instructor exited the helicopter, he explained to the solo student pilot that the helicopter was going to "pick up" differently with the absence of the flight instructor's body weight similar to the initial solo flight the day prior, and the solo student pilot "concurred and understood." The flight instructor observed the helicopter take off from the dry asphalt; however, the flight instructor reported the helicopter was "sliding back and right" as it came up. The right rear skid tube contacted the ground, the solo student pilot did not correct for the ground contact, and the helicopter entered a dynamic rollover sequence. The main rotor blades impacted the ground and the helicopter came to rest on its right side as shown below in figure 1. The solo student pilot executed an emergency shutdown and egressed from the helicopter without further incident. Figure 1 - View of the front of the helicopter (courtesy of the certificated flight instructor). The helicopter sustained substantial damage to the main rotor system, the fuselage, the tailboom, and the empennage. The flight instructor reported there were no preaccident mechanical failures or malfunctions with the airframe and engine that would have precluded normal operation. The flight instructor reported the solo student pilot was taking off from a "solid airport asphalt tarmac" and there were "no known pivot points" for the helicopter to get into a dynamic rollover sequence. The flight instructor reported the wind was from 120° at 8 kts and the helicopter was positioned into the wind before the flight instructor departed the helicopter. The previous flight operations with the flight instructor were performed to runway 12 and the solo student pilot was intending to also utilize runway 12. Robinson Helicopter Company (RHC) has published Safety Notice SN-9 Many Accidents Involve Dynamic Rollover. Thisdocument defines and discusses how to avoid dynamic rollover and states in part: A dynamic rollover can occur whenever the landing gear contacts a fixed object, forcing the aircraft to pivot about the object instead about its own center of gravy. The fixed object can be any obstacle or surface which prevents the skid from moving sideways. Once started, dynamic rollover cannot be stopped by application of opposite cyclic alone. For example, assume the right skid contacts an object and becomes the pivot point while the helicopter starts rolling to the right. Even with full left cyclic applied, the main rotor thrust vector will still pass on the left side of the pivot point and produce a rolling moment to the right instead of to the left. The thrust vector and its moment will follow the aircraft as it continues rolling to the right. Quickly applying down collective is the most effective way to stop a dynamic rollover. The flight instructor reported that with one occupant onboard, the Robinson R22 takes off from the ground with the "toes" of the skids first. RHC has published the Flight Training Guide (FTG) which contains detailed training syllabi for initial training, transition/qualification training, and flight reviews for the Robinson R22, the Robinson R44, and the Robinson R66. This document also contains a separate maneuver guide, which includes a purpose, description, and performance standards for various maneuvers. This document discusses the takeoff characteristics for the Robinson R22 with two occupants onboard, with no mention of the takeoff characteristics with one occupant onboard, and states in part: Since the R22 normally hovers in a nose low attitude with two occupants, the heels of the skids will break ground first. After a discussion with the National Transportation Safety Board investigator-in-charge, RHC agreed to incorporate additional information about the Robinson R22 takeoff characteristics with one occupant onboard to the next published edition of the FTG.