Robinson R22 BETA N4072T

Summary

On 2 July 2002 at about 21:45 local time, a Robinson R22 BETA registered N4072T, operated by Group 3 Aviation, was involved in an accident near Chatsworth, California, United States. 2 people were on board and one was seriously injured, 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

2 July 2002 at 21:45

Classification

Accident

Location

Chatsworth, California, United States

Coordinates

34.2808, -118.6096

Aircraft

Robinson R22 BETA

Registration

N4072T

Category

Helicopter

Engines

1

Operator

Group 3 Aviation

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Van Nuys → Unknown

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

LAX02LA213

1 person was seriously injured.

The pilot's inadequate flare resulting in rotor blade contact with the ground. Contributing factors were the high altitude and the airframe vibration for an undetermined reason.

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

Read the full NTSB narrative

The 2,155-hour pilot reported that the helicopter developed an abnormal vibration while en-route to a local practice area. The pilot added that he became concerned about the unusual vibration and elected to land the helicopter as soon as possible to investigate the source of the vibration. The pilot executed a power-on approach to a terraced paved area located to the right of his intended course. While on the approach on a northerly heading, as the pilot was flaring the helicopter for a landing, control was lost after the main rotor blades came in contact with the terraced terrain to his right-front. The pilot stated that the engine was performing "normally" and he did not experience a loss of engine power. He added that at the time of the accident, the winds at the accident site were from the south at an estimated 10 to 13 knots. On June 25, 2002, the Robinson Helicopter Company issued an R22 Safety Alert Letter dealing with unusual vibrations and the possibility of a main rotor blade crack. The letter states that "IF MAIN ROTOR VIBRATION INCREASES RAPIDLY OR BECOMES SEVERE DURING FLIGHT, LAND IMMEDIATELY." The pilot recalled receiving this letter three days prior to the accident and indicated this as the reason for his landing attempt. Both tail rotor blades were broken off about 3 ½ inches from their outboard mount points with severe leading edge damage to both blades. One main rotor blade was bent aft and up from its normal position leaving the trailing edge buckled. The other main rotor blade was bent aft and down from its normal position leaving the trailing edge buckled. Small cracks were observed on both main rotor blades near the root fitting and spar cover area. Due to the observed cracks in the main rotor blade root area, the sealant was removed from both blades and they were subjected to a dye penetrate inspection per Robinson Helicopter Company Service Letter 21A. No indications of cracks in the root fitting material of both blades were found.

Quoted verbatim from the NTSB record.