Lake LA 4 accident near Byron, California, July 25, 2017
On July 25, 2017 at about 8:10 pm local time, a 1969 Lake LA 4, registered N7628L, was substantially damaged in an accident during landing (flare/touchdown) near Byron, California (Byron airport). It was a personal flight under general aviation rules (Part 91). No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot’s failure to activate the hydraulic system during the approach, and his failure to ensure that the landing gear was down and locked before touchdown. Contributing to the accident was the pilot's decision to operate the airplane with an inoperative landing gear position indicator light.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 25, 2017 · about 8:10 pm local time
- Place
- Byron, California · Byron · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Lake LA 4 UNDESIGNAT, built 1969 · all LA 4s on the register
- Registration
- N7628L · registry record · serial 401
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
During landing, the nose landing gear and right main landing gear collapsed, and the airplane veered off the runway. The pilot stated that it was likely that he switched the hydraulic pump off during the accident flight. Although both the hydraulic switch position and checking the hydraulic system pressure were included in his before-landing checklist, he could not recall their position and indication, respectively, during the accident approach. The pilot also reported that he had been experiencing issues with the landing gear microswitches, and the airplane's landing gear indicator light was inoperative as a result. Postaccident examination of the airplane and landing gear system revealed no evidence of mechanical malfunctions or anomalies that would have precluded normal operation. It is likely that the pilot's failure to properly configure the hydraulic switch, and his subsequent failure to recognize the error during his before-landing check, resulted in inadequate hydraulic pressure to extend and lock the landing gear. The airplane's inoperative landing gear indicator light likely contributed to the pilot's failure to recognize that the landing gear was not fully extended and locked before landing.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
What happened, in order
- Landing gear collapse during landing (flare/touchdown) defining event
- Runway excursion during landing (landing roll)
The NTSB's findings
- Aircraft › Aircraft systems › Hydraulic power system › Hydraulic, main system › Incorrect use/operation
- Aircraft › Aircraft systems › Landing gear system › Gear position and warning › Not serviced/maintained
- Personnel issues › Task performance › Use of equip/info › Use of equip/system › Pilot
- Personnel issues › Action/decision › Info processing/decision › Decision making/judgment › Pilot
- Aircraft › Aircraft systems › Landing gear system › (general) › Incorrect use/operation
Pilot
- Certificate: private
- Ratings: single-engine land; single-engine sea
- Flight time: 790 hours in all
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: left
- Injury: no injuries
Passenger
- Seat: rgt
- Injury: no injuries
The aircraft
- Landing gear: retractable
- Engine: Lycoming O-360 (piston); 0 hours total
The flight
- Departed from: LVK Livermore CA at 8:00 pm
- Destination: C83 Byron CA
- Flight plan: none
- Runway 30, 4,500 ft by 100 ft
Weather at the time
- Light: daylight
- Wind: from 210° at 9 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 81°F (27°C), dew point 52°F (11°C)
- Altimeter: 29.92 inHg
- Observation at 7:53 pm from KLVK, 12 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
3 documents, released by the NTSB on January 5, 2021. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | FAA Examination Notes | PDF, 3 pages | View Download |
| 2 | Pilot Statement | PDF, 5 pages | View Download |
| 3 | Photo Array | PDF, 5 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.