WPR25FA277

NTSB accident investigation · Lawson Thomas O Lancair Super ES · Mount Hamilton, CA · September 12, 2025

Accident · FatalClass 3 · FieldPreliminary report
Date
September 12, 2025, 14:21 local (21:21 UTC)
Place
Mount Hamilton, CA · NE Lick Observatory on hillside
Injuries
1 fatal
Damage
Destroyed
Phase of flight
Enroute
Aircraft
N905ETLawson Thomas O Lancair Super ES
Defining event
Enroute-descent: Loss of control in flight
Weather
Visual (VMC) · Day
Status
Investigation ongoing
Investigation class
Class 3
NTSB office
Western Pacific Region
Parties
Federal Aviation Administration
FAA report
20250912015629A
Case key
200993

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

On this page

Preliminary report

What NTSB knew early in the investigation. It may change in the final report.

On September 12, 2025, about 1421 Pacific daylight time, an experimental amateur-built Lancair Super ES, N905ET, was destroyed when it was involved in an accident near Mount Hamilton, California. The pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot’s sister reported that the pilot was due to depart from Ryan Field Airport (RYN), Tucson, Arizona, with the intended destination of the Norman Y Mineta San Jose International Airport (SJC), San Jose, California. Hunters near the accident site reported observing the airplane circling their location at high speed about 1,000 ft above them. During a subsequent circling pattern, the airplane had descended to about 300 ft above ground level, then made a sharp right turn overflying their location. The airplane continued to bank to the right and “went straight down into the hillside at what sounded like full engine power.” The recorded ADS-B flight track showed that at 1300:12, the airplane was on a northeast heading at an altitude of about 8,900 ft mean sea level (msl). ADS-B contact was lost about 242 miles southwest of the accident site. Examination of the accident site revealed that the airplane impacted mountainous terrain along the western edge of a valley about 5 miles northeast of Mount Hamilton. The first identified point of contact (FIPC) was a 12 ft tall tree that had damaged limbs near the top of the tree. The debris path was oriented on a heading of about 250° magnetic and was about 90 ft in length from the FIPC. Various portions of airplanes flight control surfaces, and propeller fragments were observed throughout the debris path. The fuselage came to rest inverted on a heading of about 250° magnetic at an elevation of 2,148 ft msl.

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.

Aircraft

Registration
N905ET
Reported as
Lawson Thomas O Lancair Super ES
Category
Airplane, amateur-built
Serial number
148
Built
2006
Airframe hours
566
Damage
Destroyed
Flight
Personal · Part 91
Airworthiness certificate
Special, Experimental (Special)
Departed
RYN · Tucson, AZ
Destination
SJC · San Jose, CA
Equipment
Unknown

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.

Weather

Conditions
Visual (VMC) · Day
Wind
310° at 5 knots, gusting 14
Visibility
10 statute miles
Lowest ceiling
None
Temperature
79 °F, dew point 57 °F
Altimeter
29.95 inHg
Observed at
KRHV, 12 nm away
METAR
KRHV 122047Z 31005G14KT 10SM SKC 26/14 A2995

FAA reports on this event · 1

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