On July 18, 1993, a Hiller UH-12E (registration N4028M) operated by Bonanza Valley Aviation was involved in an aviation accident near Milbank, SD. Investigators recorded the probable cause as: The helicopter began spinning after the pilot heard a bang during hover, leading to an impact with obstacles and a post-crash fire; no pre-impact mechanical malfunction could be determined due to severe damage. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 3 related events involving the same aircraft type or operator are linked below.
A helicopter began spinning after the pilot heard a bang during a landing hover. The aircraft struck obstacles, rolled, and burned upon impact.
What happened
The pilot reported hearing an audible bang while the helicopter was in a hover phase during a landing maneuver. Immediately following this event, the aircraft began to spin uncontrollably. As it settled toward the ground, the rotorcraft struck various obstacles located near the intended landing area. The impact caused the helicopter to roll over and subsequently catch fire.
The investigation
An FAA inspector examined the wreckage to determine the cause of the incident. The inspector noted that the damage resulting from the impact was extensive. Additionally, a post-crash fire further compromised the airframe. Due to the severity of these damages, the inspector was unable to identify any pre-impact mechanical malfunctions.
Probable cause
The helicopter began spinning after the pilot heard a bang during hover, leading to an impact with obstacles and a post-crash fire; no pre-impact mechanical malfunction could be determined due to severe damage.
A SkyWalk Join't 3 paraglider crashed into the ground near Las Vizcachas, Chile, on September 1, 2024. The pilot and passenger sustained serious spinal…
PARAPENTE (ULTRALIVIANO NO MOTORIZADO)·2024-09-01DGAC Chile
A Cessna 172N struck electrical cables while on final approach to land at Aucó Aerodrome in Chile. The pilot was uninjured, but the aircraft sustained damage…
A Bombardier DHC-8-402 suffered a tail strike during landing at Puerto Williams on September 9, 2024. All 76 occupants were unharmed, but the aircraft…
A MYD JS-MD 3 glider veered off the runway and struck a wall at Vitacura Aerodrome on January 6, 2025. The pilot was uninjured, but the aircraft sustained…
A recreational paraglider flight in Puchuncaví, Chile, ended with the pilot sustaining serious injuries after a rapid descent and impact with a hillside on…
PARAPENTE (ULTRALIVIANO NO MOTORIZADO)·2025-03-29DGAC Chile
A Tecnam P2006T landed on its belly at an aerodrome in Poland after the crew failed to confirm landing gear deployment. The incident resulted in no injuries…