Robinson R22 BETA N7188J

Summary

On 12 December 2007 at about 23:15 local time, a Robinson R22 BETA registered N7188J, operated by Tim Bias, was involved in an accident near Plant City, Florida, United States. One person was on board and one had minor injuries. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

12 December 2007 at 23:15

Classification

Accident

Location

Plant City, Florida, United States

Nearest airport

Plant City Municipal Airport (PCM)

Coordinates

28.0000, -82.1586

Aircraft

Robinson R22 BETA

Registration

N7188J

Category

Helicopter

Engines

1

Operator

Tim Bias

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Lakeland → Plant City

Aircraft damage

Substantial

Weather

VMC

Light

Night/Dark

NTSB number

NYC08LA060

1 person had minor injuries.

A loss of rotor drive due to excessive slack and breakage of the drive belts. Contributing to the accident was the pilot departing in the helicopter after the rotor engagement time during engine start exceeded the time outlined in the pilot's operating handbook.

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

Read the full NTSB narrative

Shortly after departure, the pilot noted that more than "usual" forward cyclic and collective application was required to maintain the helicopter's desired airspeed, but that a scan of the instruments assured him that "All was okay." While cruising at 700 feet, and 70 knots, the pilot detected a strong odor of burning rubber, a loss of power, illumination of the clutch warning light, and yawing of the helicopter. The pilot entered autorotation, turned to a "dark, open area," and descended into trees. Examination of the helicopter at the scene revealed that the drive belts were twisted, torn, and off of their respective pulleys. Examination and testing revealed that the clutch actuator functioned as designed, but the alignment of the drive belt sheaves and pulleys could not be determined due to impact damage. In a follow-up interview, the pilot stated that during engine start, 10 to 15 seconds transpired between the times that he actuated the clutch switch, and the main rotor blades turned. According to the pilot's operating handbook starting engine checklist, the rotor blades should turn less than 5 seconds after engagement of the clutch switch. According to a note in the manufacturer's maintenance manual, V-Belt Installation, "A delay of more than 5 seconds between clutch switch engagement and rotor turning indicates excessive slack."

Quoted verbatim from the NTSB record.