WPR12CA056

NTSB accident investigation · Robinson Helicopter R22 Beta · Waipahu, HI · December 7, 2011

Accident · No injuriesData collectionFinal report
Date
December 7, 2011, 08:30 local (18:30 UTC)
Place
Waipahu, HI
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N817ABRobinson Helicopter R22 Beta
Defining event
Landing-flare/touchdown: Hard landing
Weather
Visual (VMC) · Day
Status
Completed · report February 6, 2012
Report
Approved by Office Director
NTSB office
Western Pacific Region
Parties
Federal Aviation Administration
FAA report
20111207029299A
Case key
82476

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

On this page

Probable cause

The certified flight instructor's delayed remedial action and inadequate supervision during a practice autorotation. Contributing to the accident was the student pilot's excessive application of the throttle.

Findings · 4

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Attention/monitoring: monitoring other personPersonnel issues › Psychological · Instructor/check pilotRobinson Helicopter R22 BETA: 15 casesAll aircraft: 200 casesProbable cause
Action: delayed actionPersonnel issues › Action/decision · Instructor/check pilotRobinson Helicopter R22 BETA: 35 casesAll aircraft: 894 casesProbable cause
Action: incorrect action performancePersonnel issues › Action/decision · Student/instructed pilotRobinson Helicopter R22 BETA: 18 casesAll aircraft: 1,386 casesProbable cause
Engine controlsAircraft › Aircraft power plant · Incorrect use/operationRobinson Helicopter R22 BETA: 2 casesAll aircraft: 51 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The certified flight instructor (CFI) and a student pilot, who held a foreign-issued fixed-wing certificate, were on a local training flight to practice autorotations. The CFI demonstrated the first autorotation. Prior to letting the student take the controls, she reviewed the recovery procedure again. The CFI remained on the controls while the student made the control applications. One autorotation was performed successfully. The student entered his second autorotation, and, at 1,000 feet above ground level, the CFI requested that the student perform a recovery. Rather than cracking the throttle as demonstrated, the student rolled on the throttle, and the CFI felt a yaw to the right. The CFI took control of the helicopter and countered the yaw with left pedal. The CFI noted that the engine rpm and rotor rpm were excessively high, so she decreased the throttle to lower the engine rpm. She began to raise the collective to lower the rotor rpm, but neither of the rpm needles decreased. The helicopter was maintaining a level attitude, but it was descending. During the landing, the low rotor rpm horn sounded, the helicopter touched down hard, and the tail boom separated. The CFI reported no preimpact mechanical malfunctions or failures with the helicopter that would have precluded normal operation.

Factual narrative

The certified flight instructor (CFI) and a student pilot, who held a foreign-issued fixed-wing certificate, were on a local training flight. The purpose, in part, was to practice autorotations. The CFI demonstrated the first autorotation. The CFI entered the autorotation after saying "…entering autorotation in 3-2-1" and lowered the collective while simultaneously adding right pedal for trim. Once the collective was all the way down, she closed the throttle. The CFI began to recover at an altitude of approximately 1,000 feet by cracking open the throttle and letting the governor take over after 80 percent revolutions per minute (RPM). Prior to letting the student take the controls, she reviewed the recovery procedure again. The CFI remained on the controls while the student did the control applications. One autorotation was performed successfully. The student entered his second autorotation and at 1,000 feet above ground level, the CFI requested that the student perform a recovery. The student rolled on the throttle and the CFI felt a yaw to the right. The CFI countered with left pedal and stated "I have the controls" and the student relinquished all controls. The CFI noted that the engine and rotor RPMs were excessively high so she decreased the throttle to lower the engine RPMs. She began to raise the collective to lower the rotor RPM, but neither of the RPM needles decreased. The helicopter was maintaining a level attitude but got closer to the ground. As they neared the ground, she looked for a place to land. During the landing, the low rotor RPM horn sounded and the helicopter touched down on the ground. They exited the helicopter and saw that the tail boom had separated. The CFI reported no preimpact mechanical malfunctions or failures with the helicopter that would have precluded normal operation.

Aircraft

Registration
N817AB
Reported as
Robinson Helicopter R22 Beta
Category
Helicopter
Serial number
1258
Airframe hours
6,810
Engine
Lycoming Engines O-320-B2C, 180 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Operator
Mauna Loa Helicopters
Registered owner
Stasys Aviation Leasing LLC
Airworthiness certificate
Standard, Normal
Last inspection
100 hour · August 8, 2011 · 65 hours before
Departed
HNL · Honolulu, HI
Destination
HNL · Honolulu, HI

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
39
Injuries
None
Certificates
Commercial, Flight instructor
Instrument ratings
Helicopter
Medical
Class 2, Without waivers/limitations
Last flight review
May 13, 2011
Seat
Left
Flight hours
489 total · 465 in this make and model · 53 in the last 90 days · 34 in the last 30 days
Role
Student pilot
Age
45
Injuries
None
Certificate
Foreign
Airplane ratings
Single-engine land
Medical
Class 2, Without waivers/limitations
Seat
Right
Flight hours
456 total · 6 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
Variable at 6 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
72 °F, dew point 64 °F
Altimeter
30.04 inHg

Docket · 1

The files NTSB released with the investigation on December 20, 2011, on NTSB’s docket system: statements, records, photos and specialists’ reports. 212 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.