CHI93LA365 · Grumman AA5B
Grumman AA5B · Accident: airframe, component or system failure en route
From Dupage Airport (DPA) to an unrecorded destination
Event
- NTSB case
- CHI93LA365
- 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
Grumman AA5B
- Aircraft type
- Grumman AA5
- 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
- N55VL
- Operator
- Van Loon, John A.
- Onboard fatalities
- Unknown
- Route
- From Dupage Airport (DPA), West Chicago, ILTo 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
- 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
- Airframe, component or system failure
- 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
- Propeller system/accessories, blade › Failure, total
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
THE PILOT DEPARTED FOR A LOCAL PLEASURE FLIGHT, AND WAS ABOUT 5 MILES SOUTH OF THE DEPARTURE AIRPORT WHEN THERE WAS A LOUD POP AND THE AIRPLANE BEGAN TO '...VIBRATE VIOLENTLY.' THE PILOT STATED THE VIBRATION BECAME MANAGEABLE WHEN HE REDUCED ENGINE POWER TO IDLE. HE REPORTED THE ENGINE LOST POWER COMPLETELY AS THE AIRPLANE GLIDED TOWARD THE SELECTED FORCED LANDING SITE. THE AIRPLANE LANDED HARD AND FLIPPED OVER DURING THE LANDING ROLL, COMING TO REST INVERTED. POSTACCIDENT INVESTIGATION REVEALED THE OUTBOARD 13.75 INCHES OF ONE PROPELLER BLADE SEPARATED DURING FLIGHT. THE SEPARATED PORTION WAS RECOVERED, AND BOTH PIECES OF THE FAILED BLADE WERE EXAMINED BY THE NTSB'S MATERIALS LAB. THE LAB'S EXAMINATION REVEALED THE CRACK ARREST POSITIONS EMANATED FROM A CAVITY ON THE FLAT FACE OF THE PROPELLER BLADE. THE PROPELLER WAS CHECKED FOR BALANCE, BLADE TRACK AND ANGLE, AND WAS PAINTED 9 1/2 MONTHS BEFORE THE ACCIDENT. THE CAVITY CONTAINED PAINT SIMILAR TO THE REST OF THE FLAT FACE OF THE BLADE.
Probable cause
the fatigue failure and separation of a portion of propeller blade during cruise flight. Related factors are the damage to the flat face of the blade, and inadequate maintenance inspection of the propeller.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI93LA365
- Event ID
- 20001211X13378
- Case number
- CHI93LA365
- 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: adf817818425dbe6d4ae97507a05fe2e38a80b2ba1b9a6a866ec9f3fdff1c5a2; retrieved 2026-09-23T01:37:35.803Z.