NYC99IA239 · Israel Aircraft Industries 1124
Israel Aircraft Industries 1124 · Incident: total loss of engine power (mechanical failure) en route
From Nantucket Memorial Airport (ACK) to Montgomery County Airpark (GAI)
Event
- NTSB case
- NYC99IA239
- 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
Israel Aircraft Industries 1124
- Aircraft type
- Israel 1124
- 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
- N666K
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Nantucket Memorial Airport (ACK), Nantucket, MATo Montgomery County Airpark (GAI), Gaithersburg, MD
- 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
- Total loss of engine power (mechanical 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
- Turbine assembly, turbine wheel › Fractured
Approximate · Estimated position: the centre of Nantucket, MA, the place the record names. Not the accident site.
NTSB narrative
While in a climb after departure, the left engine failed. All procedures were accomplished to secure the engine and the airplane landed uneventfully. Examination of the airplane revealed extensive damage to the left engine nacelle and turbine section. The first stage low pressure turbine rotor disk was found separated from the low-pressure turbine shaft, and had penetrated the inner stage transition liner. The engine was removed from the airplane and disassembled. The disassembly revealed the first stage low-pressure turbine (LPT) had a piece of the web and rim, missing outboard of the curvic coupling. Metallurgical examination of the ruptured first stage LPT disk revealed a high cycle fatigue failure that originated from the subsurface location. The disk's dimensions adjacent to the fracture and the disk's material properties conformed to engineering specifications.
Probable cause
A fractured turbine wheel.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record NYC99IA239
- Event ID
- 20001212X19855
- Case number
- NYC99IA239
- 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: 2eb32d6c7f941c4c985748288ad1623ac317018e4b236b3df81b80f35a5c2060; retrieved 2026-09-22T13:59:41.993Z.