LAX04FA096 · Cessna 172K
Cessna 172K · Accident: in flight encounter with weather on approach
From O17 · Grass Valley, CA to Palo Alto Airport (PAO)
Event
- NTSB case
- LAX04FA096
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 2 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Instrument Meteorological Cond
Cessna 172K
- Aircraft type
- Cessna 172
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N99LR
- Operator
- Edward R. Castro · private individual
- Onboard fatalities
- Unknown
- Route
- From O17 · Grass Valley, CATo Palo Alto Airport (PAO), Palo Alto, CA
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Approach
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- In flight encounter with weather
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Visual flight rules (VFR) flight into instrument meteorological conditions (IMC); Tree(s)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Pilot in command › Clearance, not maintained
- Pilot in command › In-flight planning/decision, improper
- Pilot in command › VFR flight into imc, intentional
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The airplane collided with trees while attempting to land in IFR conditions of near zero visibility in fog. While en route to the destination airport on an IFR clearance, the TRACON controller observed the airplane's transponder discrete code change to 7600 (used by flight crews to indicate a communications failure). The TRACON controller determined that the pilot could hear them, but they could not hear his transmissions. Because of the requirement for full communications in controlled, Class B airspace, they suggested the pilot contact a nearby airport outside of the Class B airspace on the frequency they provided. The pilot contacted the suggested ATCT while 12 miles west of that airport, and the controller could barely hear the pilot's transmissions. The pilot advised the tower to cancel his IFR flight plan and he would proceed visual flight rules (VFR) back to his departure airport without VFR flight following. This was the last communication from the pilot. Witnesses heard the pilot make two approach attempts to land at original departure airport but they could not see the airplane because the airport had become zero visibility and zero ceiling in fog about 20 minutes prior to the airplanes arrival.
Probable cause
the pilot's continued visual flight into instrument meteorological conditions and failure to maintain an adequate terrain/object clearance altitude. Also causal was the pilot's improper in-flight decision to return to the origin airport in the face of deteriorating weather conditions instead of diverting to a more suitable alternate.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record LAX04FA096
- Event ID
- 20040122X00094
- Case number
- LAX04FA096
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: local date, investigation status, coordinates. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 2004-01-20.
- API snapshot SHA-256: f081c2725e3e7845ff4e4c88f1937fc309625a23e6ceb7f438d28b3cf02a4d0e; retrieved 2026-09-20T18:36:38.552Z.