Accident Texas Helicopter M74L Wasp (Bell OH-13H) N1001N,
ASN logo
ASN Wikibase Occurrence # 162657
 
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information. If you feel this information is incomplete or incorrect, you can submit corrected information.

Date:Friday 6 December 2013
Time:16:30
Type:Silhouette image of generic B47G model; specific model in this crash may look slightly different    
Texas Helicopter M74L Wasp (Bell OH-13H)
Owner/operator:Spray Copter, LLC
Registration: N1001N
MSN: 81-037
Year of manufacture:1981
Total airframe hrs:7949 hours
Engine model:Lycoming VO-435 SERIES
Fatalities:Fatalities: 1 / Occupants: 1
Aircraft damage: Destroyed
Category:Accident
Location:near Sebring (KSEF), FL -   United States of America
Phase: Approach
Nature:Ferry/positioning
Departure airport:Sebring, FL
Destination airport:Sebring, FL (SEF)
Investigating agency: NTSB
Confidence Rating: Accident investigation report completed and information captured
Narrative:
After a day of aerial application flights, the pilot landed in a farm field and had the helicopter serviced with fuel from a truck before departing on the accident flight. A witness observed the helicopter descending toward an open field from an altitude about 150 feet above ground level. The helicopter then descended to about 50 feet, leveled briefly, then “fell” straight to the ground, and erupted in flames. The wreckage was partially consumed by a postimpact fire.
Examination of the wreckage following the accident revealed that the engine’s carburetor float bowl was absent of fuel and contaminated with a rust-colored powder, which contained both ferrous and non-ferrous metal. Detailed examination of particulate matter collected from the filter housing of the fuel truck used to service the helicopter showed those components to be similarly contaminated. Additionally, during a postaccident demonstration of the procedure used to fuel the helicopter, the initial fuel dispensed was brown and gold in color. The operator of the fuel truck noted that it was typical to continue dispensing fuel into a separate container until it “turned blue,” before beginning to fill the helicopter.
The extent to which the fuel onboard the helicopter at the time of the accident was contaminated could not be determined due to the extent of the post-impact fire and lack of available fuel samples from the helicopter. However; based on the powdered contamination recovered from the carburetor float bowl, it is likely that the fuel contamination was significant enough to result in a partial or total loss of engine power, which would have required that the pilot conduct an off-airport precautionary landing, or autorotation and forced landing.
The pilot’s toxicology testing revealed a carbon monoxide level that was consistent with the autopsy findings of abundant soot in the upper and lower airways and indicated exposure to combustion products in the postimpact fire. It was unlikely that an elevated level of carbon monoxide was present in the pilot’s blood before that crash. Toxicology testing also indicated that the pilot had used diphenhydramine before the accident. Diphenhydramine, a sedating antihistamine used to treat allergy symptoms and as a sleep aid. Diphenhydramine can cause marked sedation, altered mood, and impaired cognitive and psychomotor performance may. The pilot’s diphenhydramine levels were above the therapeutic range, but may have been redistributed following death. Thus, it is likely the pilot had therapeutic levels of diphenhydramine in his system at the time of the crash. The pilot’s time-critical decision-making and ability to perform an effective autorotation and/or landing were likely impaired by the use of diphenhydramine.

Probable Cause: A partial loss of engine power as a result of contamination of the engine’s fuel supply, and the pilot’s impaired performance due to his use of diphenhydramine, which resulted in his inability to complete a forced or precautionary autorotative landing successfully.

Accident investigation:
cover
  
Investigating agency: NTSB
Report number: ERA14FA066
Status: Investigation completed
Duration:
Download report: Final report

Sources:

NTSB

Location

Revision history:

Date/timeContributorUpdates
08-Dec-2013 01:16 Geno Added
08-Dec-2013 08:50 Alpine Flight Updated [Date, Location]
08-Dec-2013 15:38 TB Updated [Aircraft type, Location, Narrative]
09-Dec-2013 23:03 Geno Updated [Aircraft type, Registration, Cn, Operator, Departure airport, Destination airport, Source, Narrative]
10-Dec-2013 20:29 Alpine Flight Updated [Aircraft type, Operator, Location]
14-Dec-2013 07:29 Geno Updated [Time, Phase, Nature, Departure airport, Source]
13-Aug-2014 12:58 TB Updated [Aircraft type, Location, Destination airport, Source]
21-Dec-2016 19:28 ASN Update Bot Updated [Time, Damage, Category, Investigating agency]
29-Nov-2017 09:28 ASN Update Bot Updated [Operator, Other fatalities, Departure airport, Destination airport, Source, Narrative]

Corrections or additions? ... Edit this accident description

The Aviation Safety Network is an exclusive service provided by:
Quick Links:

CONNECT WITH US: FSF on social media FSF Facebook FSF Twitter FSF Youtube FSF LinkedIn FSF Instagram

©2024 Flight Safety Foundation

1920 Ballenger Av, 4th Fl.
Alexandria, Virginia 22314
www.FlightSafety.org