IAD04LA008 · Rockwell 112A
Rockwell 112A · Accident: partial loss of engine power (mechanical failure) during an emergency descent
From Cape Cod Gateway Airport (HYA) to Nashua Airport / Boire Field (ASH)
Event
- NTSB case
- IAD04LA008
- 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
- Unknown
- 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
Rockwell 112A
- Aircraft type
- Rockwell 112
- 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
- N1381J
- Operator
- GPW Aeroservices
- Onboard fatalities
- Unknown
- Route
- From Cape Cod Gateway Airport (HYA), Hyannis, MATo Nashua Airport / Boire Field (ASH), Nashua, NH
- 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
- Emergency descent
- 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
- Partial loss of engine power (mechanical failure)
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Tree(s)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Engine assembly, connecting rod cap › Failure
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
While descending through 5,500 feet on a moonless night, thick black smoke filled the cabin. The two pilots' initial assessment was that the smoke may have been the result of an electrical fire, so the pilot in command shut off the master switch and vented the cabin. The second pilot grabbed his flashlight and in checking the engine gauges, found there was no oil pressure. The pilots felt they were about to lose engine power, so the second pilot turned on the master switch to notify approach control, and requested vectors to a nearby airport. Approximately 1 minute later, about 4,500 feet, the engine began to vibrate, and lost power. The vibration intensified, and the engine began to shake violently. The pilot in command shut down the engine so it wouldn't break the engine mounts. The second pilot flew the airplane at best glide airspeed, and about 5-6 miles north of the airport, both pilots realized that they were not going to be able to reach it. They looked for a place to land, and found an area that did not appear to have people or homes in it. Approaching the ground, the pilots saw trees in the landing light, and the second pilot maneuvered the airplane to avoid any direct tree hits. Just before ground impact, the pilot in command turned off the master switch. After hitting several trees, the airplane came to a stop, and became engulfed in flames. Because the doors wouldn’t open, the pilots climbed out an opening where the windshield had been. A post-accident engine examination revealed that the #2 piston connecting rod cap had separated, and that there was a hole in the side of the engine case. The number 1, 3, and 4 cylinders were covered with black residue, and the number 2 cylinder was coated with white residue. The engine was last overhauled in September 1990, about 700 operating hours earlier. A service instruction recommended that an engine be overhauled in the 12th year after the previous overhaul, if it had not accumulated the recommended hourly time between overhauls (1,800 hours for that model engine) by that time.
Probable cause
Failure of the #2 piston connecting rod cap, which resulted in a hole in the engine crankcase and a loss of engine power. A factor was dark night lighting condition.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record IAD04LA008
- Event ID
- 20040128X00120
- Case number
- IAD04LA008
- 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: local date, investigation status, coordinates. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 2004-01-25.
- API snapshot SHA-256: a57d6d17a0a40fb87b8e0d8119bd26f21517c0b45883665ab51ab3e3d3b62789; retrieved 2026-09-21T19:17:54.761Z.