Bell 206L-1 N37AE

Summary

On 31 August 2008 at about 17:20 local time, a Bell 206L-1 registered N37AE, operated by Air Evac EMS Inc., was involved in an accident near Greensburg, Indiana, United States. 3 people were on board and 3 died. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

31 August 2008 at 17:20

Classification

Accident

Location

Greensburg, Indiana, United States

Coordinates

39.3322, -85.6203

Aircraft

Bell 206L-1

Registration

N37AE

Category

Helicopter

Engines

1

Operator

Air Evac EMS Inc.

Operating rule

Part 91: General Aviation

Purpose of flight

Positioning

Phase of flight

Not recorded

Route

Burney → Rushville

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

CHI08FA269

3 people died.

The in-flight separation of a main rotor blade due to a fatigue failure of the blade spar, rendering the helicopter uncontrollable, and the manufacturer's production of main rotor blades with latent manufacturing defects, which precipitated the fatigue failure of the blade spar.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

The emergency medical services crew had attended a local fundraising event and was returning to the helicopter/crew base when the accident occurred. Witnesses reported that the helicopter made a normal departure. They subsequently reported seeing components separate from the helicopter before it descended and impacted the ground. The helicopter came to rest in a corn field approximately 1.2 miles from the departure point. A postaccident examination of the helicopter revealed that an 8-foot section of one of the main rotor blades separated in-flight rendering the helicopter uncontrollable. Metallurgical examination determined that the blade failed as a result of fatigue cracking. The origin of the fatigue crack coincided with a large void between the blade spar and an internal lead weight. Further investigation determined that the presence of residual stresses in the spar from the manufacturing process, in combination with excessive voids between the spar and the lead weight, likely resulted in the fatigue failure of the blade. The manufacturer issued an alert service bulletin that identified main rotor blades that may have been affected by the combination of residual stresses and excessive voids between the spar and the lead weight. The service bulletin also called for supplemental inspections in order to maintain the continued airworthiness of the affected blades.

Quoted verbatim from the NTSB record.