CHI87IA061 · Nihon YS-11A-500
Nihon YS-11A-500 · Incident: airframe, component or system failure while maneuvering
From Indianapolis International Airport (IND) to Purdue University Airport (LAF)
Event
- NTSB case
- CHI87IA061
- 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
- Incident
- 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
Nihon YS-11A-500
- Aircraft type
- Nihon YS-11
- 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
- N906TC
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Indianapolis International Airport (IND), Indianapolis, INTo Purdue University Airport (LAF), Lafayette, IN
- 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
- 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
- Minor
Cause areas
- Pilot in command › Powerplant controls, improper use of
- Pilot in command › Procedures/directives, not followed
- Pilot in command › Wheels up landing, intentional
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
THE FLIGHT CREW FAILED TO ADHERE TO APPROPRIATE PROCEDURES AND DIRECTIVES WHEN THEY FAILED TO SELECT THE HP COCK LEVERS TO THE HSWL (LOCK OUT) POSITION WHILE PERFORMING AN APPROACH TO LANDING STALL DURING A TRAINING/TEST FLIGHT. WHEN STALL RECOVERY WAS INITIATED, BOTH PROPELLERS 'HUNG UP' WHEN THE HIGH (CRUISE PITCH) STOPS OF EACH PROPELLER FAILED TO WITHDRAW. AS THE POWER LEVERS WERE ADVANCED, TURBINE GAS TEMPERATURES (TGT'S) EXCEEDED LIMITATIONS; THE LEFT PROPELLER AUTO-FEATHERED, THE RIGHT PROPELLER WAS LATER FEATHERED BY THE CAPTAIN. RESTART PROCEDURES WERE ATTEMPTED WITHOUT SUCCESS, AND A FORCED LANDING IN A PLOWED CORNFIELD ENSUED. EXAMINATION OF THE ENGINES REVEALED THAT THE TURBINES HAD BEEN 'SUBJECTED TO SEVERE (AND DESTRUCTIVE) THERMAL DEGRADATION DURING OPERATION' AS A RESULT OF THE PROPELLERS BEING CONSTRAINED DURING LOW SPEED OPERATIONS. TESTING OF THE RELAYS REVEALED THAT THE HIGH STOP WITHDRAWAL RELAY FOR THE RIGHT PROPELLER FUNCTIONED INTERMITTENTLY.
Verbatim NTSB analysis from the NTSB dataset
Sources
NTSB record CHI87IA061
- Event ID
- 20001213X30050
- Case number
- CHI87IA061
- 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: bb957e30b668f23cac5c12905d8e8b6e21288ec258d2aadf524d5b737e5d911c; retrieved 2026-09-23T13:37:40.239Z.