WPR16LA156

NTSB accident investigation · Robinson R22 · Prescott, AZ · August 2, 2016

Accident · Minor injuriesLimited investigationFinal report
Date
August 2, 2016, 10:27 local (17:27 UTC)
Place
Prescott, AZ
Injuries
2 minor
Damage
Substantial damage
Phase of flight
Emergency descent
Aircraft
N22UHRobinson R22
Defining event
Autorotation: Loss of control in flight
Weather
Visual (VMC) · Day
Status
Completed · report September 10, 2018
Report
Approved by Office Director
NTSB office
Western Pacific Region
Parties
Federal Aviation Administration
FAA report
20160802012759A
Case key
93744

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 flight instructor’s delayed remedial action to address a low rotor rpm condition, which resulted in an excessive descent rate and a subsequent hard landing.

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.

Performance/control parameters: descent/approach/glide pathAircraft › Aircraft oper/perf/capability · Not attained/maintainedRobinson Helicopter R22: 4 casesAll aircraft: 809 casesProbable cause
Use of equip/info: aircraft controlPersonnel issues › Task performance · Student/instructed pilotRobinson Helicopter R22: 18 casesAll aircraft: 9,295 casesProbable cause
Attention/monitoring: monitoring other personPersonnel issues › Psychological · Instructor/check pilotRobinson Helicopter R22: 3 casesAll aircraft: 200 casesProbable cause
Action: delayed actionPersonnel issues › Action/decision · Instructor/check pilotRobinson Helicopter R22: 7 casesAll aircraft: 894 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 flight instructor and student pilot were practicing straight-in autorotations in the helicopter. During the autorotative descent, about 400 ft above ground level with the student at the controls, the instructor noticed a high rate of descent and a decay in main rotor rpm. The instructor told the student that he had the controls and started applying collective and throttle to recover rpm. He felt the collective go up and again told the student that he had the controls. The instructor was unable to arrest the descent before the helicopter landed hard and rolled over. The instructor reported that there were no pre-impact mechanical malfunctions or failures with the airframe or engine that would have precluded normal operation. He further stated that the accident could have been prevented if he had stayed ahead of his student and the helicopter.

Factual narrative

On August 2, 2016, about 1027 mountain standard time (MST), a Robinson R22 helicopter, N22UH, landed hard at Ernest A Love Field Airport, Prescott, Arizona. The certificated flight instructor and student pilot received minor injuries. The helicopter sustained substantial damage to the fuselage and the tail boom. The helicopter was registered to Alba Leasing Services and operated by Universal Helicopters under the provisions of Title 14 Code of Federal Regulations (CFR) Part 91 as an instructional flight. Visual meteorological conditions prevailed, and no flight plan was filed. The local flight departed Prescott, Arizona, about 0950. The student pilot and the flight instructor were practicing straight in autorotations. During the glide, with the student pilot at the controls, about 400 feet above ground level, the flight instructor noticed a fast rate of decent and a decay in rotor RPM. The flight instructor stated to the student that he had the controls and started applying collective and throttle control to recover RPM. The instructor felt the collective go up and stated again to the student that he had the controls. The flight instructor was unable to arrest the decent or recover RPM prior to the hard landing. During touchdown, the landing skids collapsed, the main rotor blades connected with and severed the tail boom. The helicopter came to rest on its left side. The flight instructor reported no pre-impact mechanical malfunctions or failures with the airframe or engine that would have precluded normal operation.

Aircraft

Registration
N22UH
Reported as
Robinson R22 (BETA)
Category
Helicopter
Serial number
4676
Built
2015
Airframe hours
882.7
Engine
Lycoming O-360-J2A, 145 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Airworthiness certificate
Standard, Normal
Last inspection
100 hour · June 28, 2016 · 30 hours before
Departed
PRC · Prescott, AZ
Destination
PRC · Prescott, AZ
Airport
PRC · Ernest A Love Field, runway 21R, 4,846 × 60 ft, asphalt
Equipment
Satellite tracking device, ADS-B

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
34
Injuries
Minor
Certificates
Flight instructor, Commercial
Instrument ratings
Helicopter
Medical
Class 2, Without waivers/limitations
Last flight review
October 2, 2014
Seat
Left
Restraint
3-point
Flight hours
1,119.4 total · 779.9 in this make and model · 1,046.5 as pilot in command · 123.8 in the last 90 days · 71 in the last 30 days · 2 in the last 24 hours
Role
Student pilot
Age
26
Injuries
Minor
Certificate
Student
Medical
Class 1, Without waivers/limitations
Seat
Right
Restraint
3-point
Flight hours
56 total · 56 in this make and model · 56 in the last 90 days

Weather

Conditions
Visual (VMC) · Day
Wind
140° at 3 knots
Visibility
10 statute miles
Temperature
75 °F, dew point 64 °F
Altimeter
30.26 inHg
Observed at
KPRC, 1 nm away

Docket · 2

The files NTSB released with the investigation on July 5, 2018, on NTSB’s docket system: statements, records, photos and specialists’ reports. 3.4 MB 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.