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LAX96LA343 · Aero Commander 690

20 Sept 1996 · Truckee, CA, United States

Aero Commander 690 and Burkhart Grob 102 · Accident: midair collision en route

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Event

NTSB case
LAX96LA343
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

Aircraft 1 · Aero Commander 690

Aircraft type
Aero Commander 690
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
N840DC
Operator
Unknown
Onboard fatalities
Unknown
Route
From Truckee Tahoe Airport (TRK), Truckee, CATo Mammoth Yosemite Airport (MMH), Mammoth Lakes, 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 · climb to 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
Midair collision
DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
Substantial

Aircraft 2 · Burkhart Grob 102

Aircraft type
Grob 102
Category
Glider
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
N22ZB
Operator
Soar Truckee
Onboard fatalities
Unknown
Route
From Juwata International Airport / Suharnoko Harbani AFB (TRK)To not recorded
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
Maneuvering
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
Midair collision
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

  • Pilot in command › Visual lookout, inadequate
  • Pilot of other aircraft › Visual lookout, inadequate

Approximate · Estimated position: the centre of Truckee, CA, the place the record names. Not the accident site.

NTSB narrative

The Aero Commander 690, N840DC, collided with the Grob 102 glider, N22ZB, while climbing through 10,000 feet msl 4 miles south of the airport. The Aero Commander pilot had announced his departure on runway 28 on the unicom frequency of 122.8 Mhz while taxiing. After departing, the pilot turned left and was heading southeast in a climb. The glider had departed the airport about 1 hour earlier via aero tow and was orbiting left in a thermal. The glider pilot was monitoring the frequency 123.3 Mhz, an air-to-air frequency used by glider pilots. Moments before the collision, the Aero Commander pilot was tuning a navigation radio. He looked up and saw the glider in his windshield, but was unable to avoid the collision. The glider pilot never saw the Aero Commander. The left wing of the Aero Commander struck the left wing and fuselage of the glider about 9,800 feet msl. Both pilots were able to safely land their airplanes at the Truckee Airport after the collision.

Probable cause

The inadequate visual lookout by both pilots while in the vicinity of the airport. A factor was that each aircraft was on a different frequency at the time.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record LAX96LA343
Event ID
20001208X06780
Case number
LAX96LA343
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: 4a14ed1bf469bd3e7261de60edea7a1f431bd6feb131ce5760061f00c8444757; retrieved 2026-09-22T21:06:27.107Z.