Casualties unknown

1998-05-18: Bell 206L-1 (N41BL) — Arlington Hgts, IL

Arlington Hgts, IL, US

On May 18, 1998, a Bell 206L-1 (registration N41BL) was involved in an aviation accident near Arlington Hgts, IL. Investigators recorded the probable cause as: Loss of helicopter control for unknown reasons. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

Witnesses reported a helicopter banking sharply before descending nose-first. Examination found no mechanical anomalies; pilot's urine tested positive for chlorpheniramine.

Witness Observations

A witness observed a helicopter flying over his apartment building at an altitude of less than 100 feet. The helicopter then traveled away from the building on a southwesterly heading in a level attitude, with the witness estimating its altitude at approximately 350 feet above the ground. The witness reported seeing the helicopter initiate a slow banked turn to the left toward a southerly heading. The bank angle increased from 30 degrees to 90 degrees, after which the helicopter pitched down and descended at a nose-down angle of 70 to 80 degrees. The witness lost sight of the helicopter when it descended below the tree tops.

Another witness in the same building stated that as the helicopter was moving westward, it was getting closer to the tree tops. This witness reported that the helicopter "banked real hard [to the] south, so that the [main rotor] blades were perpendicular to the ground." The helicopter then "went straight down in a dive, nose first." The witness said the helicopter was only 15 feet above the tree tops when it dove in.

Examination Findings

Examination of the wreckage revealed no anomalies.

Toxicology Results

FAA toxicology testing of specimens from the pilot detected 0.007 (ug/ml, ug/g) chlorpheniramine in urine.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001211X09996. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.