A report released by the NTSB Thursday stated, "It is likely that the pilot inadvertently encountered localized icing conditions, which resulted in his subsequent in-flight loss of helicopter control."
The helicopter was carrying pilot Gene Grell, nurse Shelly Lair-Langenbau and paramedic Russ Piehl. They were on their way to pick up a patient in Emmetsburg when the helicopter crashed into a farm field.
According to the final NTSB report, observations from the nearest Automated Surface Observing System, located about 7 miles east of the accident site, indicated visibility appeared to be adequate for nighttime helicopter operations and did not detect any freezing precipitation.
Although an advisory for icing conditions was current for the route of flight, and several pilot reports of icing conditions had been filed, "none of the reports were in the immediate vicinity of the intended route of flight," the report stated.
Witnesses and first responders reported mist, drizzle and icy road conditions at the time of the accident, according to the report.
The helicopter had heated ports but the rotor blades were not equipped with ice protection, according to a preliminary NTSB report released in August 2014.
"The helicopter was not certified for intentional flight into known icing conditions," that report stated.
Lair-Langenbau's husband, Jay Langenbau, two minor children and her parents, Gerald and Karen Lair, filed a lawsuit in Cerro Gordo County District Court in July 2013. It was moved to federal court the next month.
The defendant in the case is Med-Trans Corp., Lewisville, Texas, which operates the helicopter service under contract to Mercy Medical Center-North Iowa.
The family is alleging negligence on the parts of Med-Trans Corp. and pilot Grell for taking off in icy conditions.
A jury trial has been set for Nov. 9 in the U.S. Courthouse in Sioux City.
The suit claims Med-Trans knew that Bell 407 helicopters were not safe to operate in certain weather conditions, including icing.
Story and photo: http://globegazette.com
NTSB Identification: CEN13FA122
14 CFR Part 91: General Aviation
Accident occurred Wednesday, January 02, 2013 in Clear Lake, IA
Probable Cause Approval Date: 02/12/2015
Aircraft: BELL HELICOPTER 407, registration: N445MT
Injuries: 3 Fatal.
NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
GPS tracking data revealed that, after departure, the helicopter proceeded westbound about 600 ft above ground level (agl), following a roadway. About 6 minutes after liftoff, when the helicopter was about 3/4 mile south of the accident site, it turned right and became established on a northerly course. The helicopter subsequently turned left and appeared to be on a southerly heading at the final data point. Shortly before beginning the left turn, the helicopter entered a climb, reached an altitude of about 1,800 ft agl, and then entered a descent that continued until impact. Weather observations from the nearest Automated Surface Observing System, located about 7 miles east of the accident site, indicated that the ceilings and visibility appeared to be adequate for nighttime helicopter operations and did not detect any freezing precipitation. Although an airmen’s meteorological information advisory for icing conditions was current for the route of flight, and several pilot reports of icing conditions had been filed, none of the reports were in the immediate vicinity of the intended route of flight. Witnesses and first responders reported mist, drizzle, and icy road conditions at the time of the accident. It is likely that the pilot inadvertently encountered localized icing conditions, which resulted in his subsequent in-flight loss of helicopter control. A postaccident examination of the helicopter revealed no preimpact failures or malfunctions. The engine control unit recorded engine torque, engine overspeed, and rotor overspeed events; however, due to their timing and nature, the events were likely a result of damage that occurred during the impact sequence. Evidence also indicated that the cyclic centering, engine overspeed, and hydraulic system warning lights illuminated; it is also likely that their illumination was associated with the impact sequence. Further, the engine anti-ice status light was illuminated, which was consistent with the activation of the anti-ice system at some point during the accident flight.
The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The pilot’s inadvertent encounter with localized icing conditions and his subsequent in-flight loss of helicopter control.
Here is the full text of the report: http://www.ntsb.gov
http://registry.faa.gov/N445MT
http://www.med-trans.net/aircraft
Gene Grell
Shelly Lair-Langenbau
Russ Piehl
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