LAX99LA170

NTSB accident investigation · Wsk Pzl Warzawa-Okecie PZL-104 Wilga 80 · Reno, NV · May 6, 1999

Accident · No injuriesLimited investigationFinal report
Date
May 6, 1999, 10:30 local (17:30 UTC)
Place
Reno, NV
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N4UUWsk Pzl Warzawa-Okecie PZL-104 Wilga 80
Weather
Visual (VMC) · Day
Status
Completed · report November 22, 2000
Report
Approved by Office Director
FAA report
19990506004669A
Case key
46261

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 flight instructor's improper supervision of the pilot trainee and his failure to make timely control inputs in order to maintain aircraft control.

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.

Loss of control - on ground/waterLanding - roll
Weather condition - tailwind
Rudder - improper use ofDual student
Remedial action - delayedPilot in command(cfi)Cause
Supervision - inadequatePilot in command(cfi)Cause
Ground loop/swerve - encountered
Nose overLanding - roll

Analysis

The flight instructor reported that they were landing on runway 26 and the aircraft touched down on the runway centerline with a slight crab to the left. The flight instructor stated that the pilot trainee 'overcorrected with right rudder input causing a swerve to the right.' The pilot trainee applied left rudder but the aircraft continued to veer to the right. The flight instructor reported that he took the flight controls in an effort to correct the drift, but realized that the 'swerve had become uncontrollable.' He stated that he felt it was too late to recover by applying engine power, so he began to apply control inputs for a ground loop. As the aircraft began to ground loop, the left wing contacted the runway surface. The flight instructor reported that the tail of the aircraft began to rise, and the combination of a slight tail wind, a left wing heavy fuel load, and possible excessive braking resulted in the aircraft pitching over and coming to rest inverted on the runway. The flight instructor reported that the automated weather observation service (AWOS) at the airport indicated that the winds were from the east at 4 knots at the time of the accident.

Factual narrative

On May 6, 1999, at 1030 hours Pacific daylight time, a WSK-PZL Warzawa-Okecie PZL-104 Wilga 80, N4UU, (a Polish manufactured airplane), ground looped while landing at the Reno-Stead Airport, Reno, Nevada. The experimental aircraft, owned and operated by the private pilot, sustained substantial damage. Neither the airline transport licensed flight instructor nor the private pilot trainee were injured. The local area instructional flight was conducted under the provisions of 14 CFR Part 91 and originated about 0830 from the Reno-Stead Airport. Visual meteorological conditions prevailed and no flight plan was filed.

The flight instructor reported that they were landing on runway 26 and the aircraft touched down on the runway centerline with a slight crab to the left. The flight instructor stated that the pilot trainee "overcorrected with right rudder input causing a swerve to the right." The pilot trainee applied left rudder but the aircraft continued to veer to the right. The flight instructor reported that he took the flight controls in an effort to correct the drift, but realized that the "swerve had become uncontrollable." He stated that he felt it was too late to recover by applying engine power, so he began to apply control inputs for a ground loop. As the aircraft began to ground loop, the left wing contacted the runway surface. The flight instructor reported that the tail of the aircraft began to rise, and "the combination of a slight tail wind, approximately 8 gallon fuel imbalance (left wing heavy), and possible excessive braking resulted in the aircraft pitching over and coming to rest inverted on the runway." The flight instructor reported that the automated weather observation service (AWOS) at the airport indicated that the winds were from the east at 4 knots at the time of the accident.

Aircraft

Registration
N4UU
Reported as
Wsk Pzl Warzawa-Okecie PZL-104 Wilga 80 (PZL-104 WI)
Category
Airplane
Serial number
CF21910927
Airframe hours
459
Engine
Pzl-Kalisz AI-14KA, 262 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Registered owner
Thomas Irwin
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Annual · July 12, 1998 · 67 hours before
Departed
4SD
Airport
4SD · Reno-Stead, runway 26, 7,600 × 150 ft, asphalt

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

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
40
Certificates
Flight instructor, Airline transport, Commercial
Airplane ratings
Single-engine sea, Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--no waivers/lim.
Seat
Right
Flight hours
7,093 total · 33 in this make and model · 5,835 as pilot in command · 10 in the last 90 days · 5 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
None
Temperature
64 °F, dew point 27 °F
Altimeter
30.00 inHg
Observed at
RNO, 12 nm away

FAA reports on this event · 1

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