- 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.
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.