Robinson R22 N8413Q

Summary

On 4 March 1992 at about 22:35 local time, a Robinson R22 registered N8413Q, operated by Wesley F. Morris, was involved in an accident near Maricopa, Arizona, United States. One person was on board and one died. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

4 March 1992 at 22:35

Classification

Accident

Location

Maricopa, Arizona, United States

Coordinates

Not recorded

Aircraft

Robinson R22

Registration

N8413Q

Category

Helicopter

Engines

1

Operator

Wesley F. Morris

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Unknown → Chandler

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

LAX92FA137

1 person died.

DESTRUCTIVE MAST BUMPING FOR AN UNDETERMINED REASON(S).

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

Read the full NTSB narrative

THE WRECKAGE WAS LOCATED ON FLAT DESERT TERRAIN ALONG A DIRECT COURSE LINE BETWEEN THE DEPARTURE & DESTINATION AIRPORTS. THE TAIL BOOM HAD SEPARATED IN FLIGHT. DAMAGE WAS CONSISTENT WITH A LOW 'G' EVENT RESULTING IN A RAPID RIGHT ROLL & SUBSEQUENT MAIN ROTOR BLADE STRIKE ON THE LEFT SIDE OF THE CABIN. THE DESIGN STRENGTH OF THE TAIL CONE'S ATTACHMENT POINTS WAS EXCEEDED. ACCORDING TO THE MANUFACTURER'S PAPER ON LOW 'G' MAST BUMPING, BOTH LATERAL CONTROL AND DAMPING IN ROLL ARE PROPORTIONAL TO G-LOAD; IN A TWO G PULLUP THEY BOTH DOUBLE, AND IN A ZERO G PUSHOVER THEY BOTH GO TO ZERO. WHEN THEY ARE ZERO, THE PILOT HAS NO LATERAL CONTROL, AND THE HELICOPTER HAS NO DAMPING IN ROLL. THE PILOT WAS REPORTEDLY KEENLY AWARE THAT ONE SHOULD NOT PLACE THE R22 INTO A NEGATIVE 'G' SITUATION, OR EVEN A LOW 'G' SITUATION, AND WAS VERY KNOWLEDGEABLE OF THE R22'S STRUCTURE AND SYSTEMS.

Quoted verbatim from the NTSB record.