SEA02LA026

NTSB accident investigation · Robinson R22 Beta · Renton, WA · January 11, 2002

Accident · Minor injuriesLimited investigationFinal report
Date
January 11, 2002, 11:31 local (19:31 UTC)
Place
Renton, WA
Injuries
2 minor
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N7185ARobinson R22 Beta
Weather
Visual (VMC) · Day
Status
Completed · report February 25, 2003
Report
Approved by Office Director
Parties
FAA - Seattle FSDO
FAA report
20020111002309A
Case key
54010

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The NTSB’s determination of the probable cause, and any contributing factors.

The flight instructor's failure to ensure that adequate altitude/clearance above the ground was maintained during hovering flight, resulting in an inadvertent ground contact and subsequent loss of control of the helicopter. A factor was the flight instructor's failure to ensure adequate control of the aircraft was maintained in the hover.

Analysis

The accident occurred during a hover demonstration to a prospective student on an introductory helicopter flight. The dual student reported that at the time of the accident, they were hovering at 4 to 5 feet. The dual student reported that the instructor had a hold of the cyclic, and that "I had a loose grip on it and we tipped back." The student stated that "We went straight up in the air for ten to fifteen feet and immediately banked left, almost up side down." The instructor reported that after demonstrating hovering flight to the student, she had the student take hold of the cyclic control with her. She stated that while maintaining control of the collective and pedals, she verified cyclic control transfer with the student and let her hand loose around the cyclic grip. The instructor reported that the helicopter then began to drift slightly sideways, forward and backward. She stated that she then took the cyclic control back and stabilized the hover. She stated that she then briefly described hovering flight to the student again, then had him take hold of the cyclic with her again as she kept control of the collective and pedals. She stated that after verifying cyclic control transfer with the student, she again let her hand loose around the cyclic grip. She reported that the helicopter then started to move forward. She stated that the student "reacted by applying gradual aft cyclic at first, then quickly applied more aft cyclic." She stated that, "Before full correction could be applied, the aircraft hit the ground. The helicopter then lifted back up a little, and started spinning to the right before falling on its side." The operator's accident report to the NTSB indicated that no mechanical malfunction or failure was involved in the accident.

Factual narrative

The factual narrative449 words

On January 11, 2002, approximately 1131 Pacific standard time, a Robinson R22 Beta helicopter, N7185A, being operated by Classic Helicopter Corporation of Seattle, Washington, on a 14 CFR 91 instructional flight, was substantially damaged when it inadvertently contacted the ground and rolled over during an in-ground-effect hover demonstration in a vacant lot in a practice area in Renton, Washington. The certificated flight instructor (a commercial pilot) and a dual student receiving an introductory helicopter flight lesson received minor injuries. Visual meteorological conditions, with calm winds, were reported at Renton at 1053, and the local flight, which departed King County International Airport/Boeing Field, Seattle, Washington, about 1105, was not on a flight plan.

The dual student reported that at the time of the accident, they were hovering at 4 to 5 feet. The dual student reported that the instructor had a hold of the cyclic, and that "I had a loose grip on it and we tipped back." The student stated that "We went straight up in the air for ten to fifteen feet and immediately banked left, almost up side down."

The instructor reported that prior to flight, she gave the student a safety briefing in accordance with Special Federal Aviation Regulation (SFAR) No. 73, consisting of a discussion on the use of controls and transfer of controls, low G condition and mast bumping, RPM management, and safe altitude and airspeed pertaining to energy management. She stated that after demonstrating hovering flight to the student, she had the student take hold of the cyclic control with her. She stated that while maintaining control of the collective and pedals, she verified cyclic control transfer with the student and let her hand loose around the cyclic grip. The instructor reported that the helicopter then began to drift slightly sideways, forward and backward. She stated that she then took the cyclic control back and stabilized the hover. She stated that she then briefly described hovering flight to the student again, then had him take hold of the cyclic with her again as she kept control of the collective and pedals. She stated that after verifying cyclic control transfer with the student, she again let her hand loose around the cyclic grip. She reported that the helicopter then started to move forward. She stated that the student "reacted by applying gradual aft cyclic at first, then quickly applied more aft cyclic." She stated that, "Before full correction could be applied, the aircraft hit the ground. The helicopter then lifted back up a little, and started spinning to the right before falling on its side." The operator's accident report to the NTSB indicated that no mechanical malfunction or failure was involved in the accident.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

In flight collision with terrain/waterHover - in ground effect
Aircraft control - inadequatePilot in command(cfi)Factor
Altitude/clearance - not maintainedPilot in command(cfi)Cause
Loss of control - in flightHover - in ground effect
In flight collision with terrain/waterDescent - uncontrolled
Roll overDescent - uncontrolled

Aircraft

Registration
N7185A
Reported as
Robinson R22 Beta
Category
Helicopter
Serial number
2997
Airframe hours
1,862
Engine
Lycoming O-360-J2A, 180 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Registered owner
Classic Helicopter Corp.
Airworthiness certificate
Standard, Normal
Last inspection
100 hour · December 14, 2001 · 67.3 hours before
Departed
BFI · Seattle, WA

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew · 2

As NTSB recorded them. NTSB leaves out names.

Role
Flight instructor
Age
27
Injuries
Minor
Certificates
Flight instructor, Commercial
Medical
Class 2, Valid Medical--w/ waivers/lim
Last flight review
April 25, 2001
Seat
Left
Flight hours
475 total · 465 in this make and model · 395 as pilot in command · 88 in the last 90 days · 24 in the last 30 days · 2 in the last 24 hours
Role
Student pilot
Age
31
Injuries
Minor
Seat
Right

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
9,500 ft broken
Temperature
48 °F, dew point 45 °F
Altimeter
30.26 inHg
Observed at
RNT, 3 nm away

Docket · 4

The files NTSB released with the investigation on November 15, 2002, on NTSB’s docket system: statements, records, photos and specialists’ reports. 458 KB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.