Sikorsky S-76A N521AC

Summary

On 14 September 1983 at about 23:23 local time, a Sikorsky S-76A registered N521AC was involved in an accident near Chicago, Illinois, United States. 6 people were on board and 3 had minor injuries. The aircraft was destroyed. No probable cause statement is available for this record.

Date

14 September 1983 at 23:23

Classification

Accident

Location

Chicago, Illinois, United States

Coordinates

41.8801, -87.6410

Aircraft

Sikorsky S-76A

Registration

N521AC

Category

Helicopter

Engines

2

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Executive/Corporate

Phase of flight

Not recorded

Route

Chicago → Grand Rapids

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

CHI83FA428

3 people had minor injuries.

The NTSB has not published a probable cause for this record. No probable cause statement is present in the source data.

Nothing about the cause is stated here that is not in the source record.

Read the full NTSB narrative

WHILE CRUISING AT 2000 FT MSL & 150 KTS, THE CREW HEARD A LOUD NOISE, AND SIMULTANEOUSLY, THE HELICOPTER YAWED APRX 30 TO 40 DEG TO THE RIGHT & PITCHED NOSE DOWN. THE AIRCREW BEGAN AN AUTOROTATION & ACTIVATED THE EMERGENCY FLOATS. THE HELICOPTER CONTINUED IN A RIGHT DESCENDING TURN DURING THE AUTOROTATION. TOUCHDOWN IN THE WATER (LAKE MICHIGAN) OCCURRED WITH A FORWARD SPEED OF ABOUT 40 TO 50 KTS. AFTER CONTACTING THE WATER, THE HELICOPTER TURNED AN ADDITIONAL 180 DEG, THEN LISTED ABOUT 10 DEG TO THE LEFT. THE OCCUPANTS DONNED THEIR LIFE VESTS & EXITED THE HELICOPTER. ABOUT 11 TO 13 MINUTES AFTER LANDING, THE ACFT ROLLED OVER IN THE WATER & EVENTUALLY SUNK. THE OCCUPANTS WERE RESCUED BEFORE THE HELICOPTER SANK. AN INVESTIGATION REVEALED THAT THE LEFT SIDE TAIL ROTOR CABLE. PN 76400-03191-043, HAD FAILED WHERE IT HAD BEEN RUBBING. THE RUBBING WAS ATTRIBUTED TO INCORRECT ROUTING OF THE CABLE.

Quoted verbatim from the NTSB record.