ANC23LA009

NTSB accident investigation · Beech 77 · Lihue, HI · December 15, 2022

Accident · Serious injuriesClass 3 · LimitedFinal report
Date
December 15, 2022, 12:05 local (22:05 UTC)
Place
Lihue, HI
Injuries
1 serious, 1 minor
Damage
Substantial damage
Phase of flight
Takeoff
Aircraft
N991ABBeech 77
Defining event
Takeoff: Aerodynamic stall/spin
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 3
NTSB office
Alaska Regional Office
Parties
FAA
FAA report
20221215019539A
Case key
106474

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 airplane’s exceedance of its critical angle of attack after encountering a downdraft during departure, which resulted in an aerodynamic stall and impact with terrain.

Findings · 2

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.

Wind: downdraftEnvironmental issues › Conditions/weather/phenomena · Awareness of conditionBeech 77: 1 caseAll aircraft: 178 casesProbable cause
Aircraft capability: climb capabilityAircraft › Aircraft oper/perf/capability · Capability exceededBeech 77: 2 casesAll aircraft: 183 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 pilot reported that, during departure, he could not climb the airplane, which stalled toward the end of the runway and descended into terrain at the edge of the airport property, resulting in substantial damage to both wings and fuselage. The pilot of a commercial airplane that departed shortly before the accident airplane reported poor climb performance during departure. A review of the topography for the runway that was used for both takeoffs indicated the possibility of downdraft conditions on the departure path of the runway. It is likely that the airplane encountered a downdraft during departure that exceeded the climb capability of the airplane and resulted in the airplane exceeding its critical angle of attack, entering an aerodynamic stall, and descending into terrain.

Factual narrative

On December 15, 2022, about 1205 Hawaii-Aleutian standard time, a Beech 77 airplane, N991AB, sustained substantial damage when it was involved in an accident at Lihue Airport (PHLI), Lihue, Hawaii. The pilot sustained serious injuries and the passenger sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot stated that he conducted a preflight inspection and an engine run-up with no anomalies noted. The airplane departed from runway 21 at PHLI. The automatic terminal information service (ATIS) information reported that the wind was from 170° at 12 knots, the tower assigned him runway 21 and not runway 17. During climbout, when the airplane was about 100 to 200 ft above ground level (agl), the airplane stopped climbing. The pilot noted no change in engine noise and reported that all cockpit indications were normal except for the vertical speed indicator, which was moving between 0 and 100 ft per minute and possibly below zero. Toward the end of the runway, the airplane stalled, descended, and impacted a fence at the edge of the airport property. The airplane came to rest just past the airport fence into a storage yard. The airplane sustained substantial damage to both wings and the fuselage. In the NTSB Pilot/Operator Accident Report (Form 6120.1), the pilot reported no preimpact mechanical malfunctions or failures with the airplane that would have precluded normal operation. The airplane was equipped with a JPI-700 engine data monitor. The data revealed engine exhaust gas temperatures and cylinder head temperatures were increasing throughout the flight with no signs of decreasing temperatures. A review of the Airport Facility Directory information for PHLI indicated no warning or notices for any potential turbulence or wind shear conditions for departures on runway 21. A review of the topography indicated an east-to-west ridge that rises to about 2,297 ft about 4 miles southwest of the centerline of runway 21; the ridge could produce downdraft conditions with strong southerly low-level wind on the departure path for runway 21. Departures on runway 17 at PHLI would not result in any turbulence or downdrafts because there is no terrain directly south of the airport. A pilot for a commercial operator departed from runway 21 about 20 minutes before the accident airplane. This pilot reported that his airplane was “always” at or above 800 ft agl at the end of the runway; on this departure, the airplane was only at 300 ft agl. The pilot also reported that downdrafts from the mountain (when using runway 21) are not detected by airport wind sensors. In addition, this pilot reported that company pilots are now required to use runway 17 and avoid runway 21.

Aircraft

Registration
N991AB
Reported as
Beech 77
Category
Airplane
Serial number
WA-79
Built
1980
Airframe hours
3,503
Engine
Lycoming O-235 SERIES, 115 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Standard, Normal
Last inspection
Annual · December 1, 2022 · 3 hours before
Destination
Same as departure
Airport
PHLI · Lihue Airport, runway 21, 6,500 × 150 ft, asphalt
Equipment
ADS-B, Angle of attack indicator, Stall warning system

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
43
Injuries
Serious
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, Without waivers/limitations
Last flight review
July 29, 2021
Seat
Left
Flight hours
255 total · 40.4 in this make and model · 222 as pilot in command · 4 in the last 90 days · 4 in the last 30 days · 0 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
160° at 10 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
81 °F, dew point 68 °F
Altimeter
29.82 inHg
Turbulence
Unknown
METAR
SA 15/12/2022 02:53-> METAR PHLI 150253Z 09006KT 10SM FEW022 BKN029 26/20 A2986 RMK AO2 SLP109 T02610200 55002 $=

Docket · 8

The files NTSB released with the investigation on November 7, 2023, on NTSB’s docket system: statements, records, photos and specialists’ reports. 11.8 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.