LAX98LA025 · Ciernia GLASAIR-III GLASAIR-II
Ciernia GLASAIR-III GLASAIR-II · Accident: total loss of engine power (non-mechanical) en route
From Phoenix Sky Harbor International Airport (PHX) to San Luis County Regional Airport (SBP)
Event
- NTSB case
- LAX98LA025
- 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
- 0 · all aircraft and ground
- Ground fatalities
- 0
- 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
- Visual Meteorological Cond
Ciernia GLASAIR-III GLASAIR-II
- Aircraft type
- Ciernia GLASAIR-III
- 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
- N153JC
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Phoenix Sky Harbor International Airport (PHX), Phoenix, AZTo San Luis County Regional Airport (SBP), San Luis Obispo, 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
- En route · cruise
- 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
- Total loss of engine power (non-mechanical)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Electrical system, battery › Discharged
- Pilot in command › Aircraft preflight, inadequate
- Pilot in command › Alternator, not set
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The aircraft is equipped with dual electronic ignition instead of magnetos. After leveling off on top, the pilot noticed that his panel indicated a loss of electrical power. After the battery was depleted, the engine quit and the aircraft descended into IMC conditions. After breaking out, he initiated a forced landing. The aircraft struck a berm and slid to a stop. The pilot stated that the alternator switch was on and that the alternator out warning light had not illuminated prior to his electrical loss. After recovery, the batteries were charged and the engine was started. When the alternator switch was moved to the off position, the alternator out warning light did not illuminate. The continuity of the light bulb was confirmed. The light socket failed a similar continuity check. The flight instructor who checked the pilot out in the aircraft reported that he did not always use the checklist and had forgotten to turn the alternator switch on before starting on several occasions.
Probable cause
A loss of engine power due to the eventual loss of electrical power which resulted from the pilot's failure to ensure the alternator switch was on as specified in the before starting checklist. The inoperative alternator out warning light was a factor in this accident.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record LAX98LA025
- Event ID
- 20001208X09068
- Case number
- LAX98LA025
- 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: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: b96a25106f816a193f495575ce8aea653cee4dec66942033a39e67f3ef24218a; retrieved 2026-09-22T18:23:29.174Z.