- Location: Spring Branch, Texas
- Accident Number: CEN24FA167
- Date & Time: April 29, 2024, 15:12 Local
- Registration: N829SH
- Aircraft: Vertical Aviation Technologies
Hummingbird
- Aircraft Damage: Destroyed
- Defining Event: Unknown or undetermined
- Injuries: 2 Fatal
- Flight Conducted Under: Part 91: General aviation - Air drop
https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/194169/pdf
https://data.ntsb.gov/Docket?ProjectID=194169
On April 29, 2024, about 1512 central daylight time, a Vertical Aviation Technologies
Hummingbird 260L helicopter, N829SH, was destroyed when it was involved in an accident
near Spring Branch, Texas. The airline transport pilot and the pilot-rated passenger sustained
fatal injuries. The helicopter was operated as a Title 14 Code of Federal Regulations Part 91 air
drop flight.
The pilot departed in the experimental helicopter with a pilot-rated passenger to perform a golf
ball drop for a charity event. Flight track data showed that the beginning of the flight was not
captured, as the first data point indicated the helicopter was in flight and was approximately
4.3 miles to the northeast of the departure airport and about 1.8 miles to the northwest of the
planned golf ball drop location. The data showed the helicopter flying to the southwest of the
first data point. The helicopter continued to travel to the southwest, and it then turned to the
southeast where the data terminated shortly thereafter at the accident site, which was located
about 1.4 miles to the northwest of the departure airport.
Multiple witnesses near the accident site heard the engine produce sputtering and coughing
noises just prior to impact. Security camera footage showed the helicopter impact a grass
field in a residential area, in front of a house. A postimpact explosion and fire occurred, which
consumed the wreckage.
While no mechanical anomalies were found during the airframe and the engine examination,
the examination was limited due to the extensive fire damage present. Multiple golf balls were
found in the wreckage, which is indicative that the golf ball drop was not completed. The
recovered flight track data showed that the helicopter was possibly flying back to the
departure airport; however, the intended flight path was not established.
The pilot had previously contacted the helicopter kit manufacturer about ethanol in fuel “eating
up” the fuel bladder in the helicopter and causing the fuel lines to “clog.” The kit manufacturer
offered to sell the pilot a new fuel bladder to install in the helicopter, but they never heard back
from the pilot. According to the FAA, ethanol in automobile fuel is not compatible with the rubber seals and other materials used in aircraft, which could cause fuel system deterioration
and malfunction.
The current helicopter maintenance records were not available for review, and the investigation
was unable to determine what maintenance had been performed on the airframe and the
engine in the several years prior to the accident.
Based upon the statements of multiple witnesses, the engine likely sustained a total loss of
engine power, which resulted in a forced landing and a subsequent impact with terrain. While it
is possible that the cause of the loss of the engine power may have been due to the
deterioration of the fuel system from the presence of ethanol in fuel, the extensive fire damage
precluded examination.
Due to heart disease, the pilot was at increased risk of a sudden impairing or incapacitating
cardiac event, including angina, arrhythmia, or heart attack. There is no autopsy evidence that
such an event occurred. However, such an event does not leave reliable autopsy evidence if it
occurs immediately before death.
The pilot’s toxicological results indicated use of gabapentin, which the FAA considers a “do not
fly” medication. Based on the gabapentin levels measured in the pilot’s heart blood, he was
possibly experiencing some effects from his use of the gabapentin; however, specific effects
are uncertain and whether he may have been impaired could not be determined based on the
level detected alone.
- Probable Cause: A total loss of engine power for undetermined reasons, which resulted in a forced landing and a subsequent impact with terrain.