FTW98FA186 · Foster/Hilsman Q2
Foster/Hilsman Q2 · Accident: partial loss of engine power (mechanical failure) en route
From Smith Field (SLG) to an unrecorded destination
Event
- NTSB case
- FTW98FA186
- 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
- 2 · 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
Foster/Hilsman Q2
- Aircraft type
- Foster/hilsman Q2
- 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
- N996DT
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Smith Field (SLG)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
- 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
- Partial 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
- Destroyed
Cause areas
- Pilot in command › Aircraft control, not maintained
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The amateur-built experimental Quickie airplane, occupied by a commercial pilot and a pilot-rated passenger, who were the co-owners/builders of the airplane, impacted the ground in a steep left bank during a forced landing following a partial loss of engine power. Disassembly of the engine revealed that six cylinder head hold-down nuts were loose, and combustion gases had been leaking between the cylinder heads and the barrels of the #2, #3, and #4 cylinders. The escaping gases cut a passage about 3/4 inch in diameter through the #4 cylinder head, resulting in the partial loss of engine power. Maintenance records indicated new cylinder heads were installed 33 hours before the accident in May 1997. A condition inspection of the airplane, which would have included a cylinder compression check, was due in November 1997, but had not been performed. According to a family member, the two owners were in the process of performing a condition inspection on the day of the accident; however, neither owner held a repairman certificate for the airplane or was a certificated airframe and powerplant mechanic.
Probable cause
The pilot's failure to maintain aircraft control during the forced landing. Factors were the failure of the #4 cylinder head which resulted in a partial loss of engine power and the co-owners/builders' failure to perform a condition inspection of the airplane, which would have detected the leaking cylinder heads prior to the failure of the #4 cylinder head.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record FTW98FA186
- Event ID
- 20001211X09844
- Case number
- FTW98FA186
- 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. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 1998-04-19.
- API snapshot SHA-256: 0debbd7fc00538f83961c7ca10e7a2e4975e483c4a1e7717ded530841ead5ce5; retrieved 2026-09-20T22:37:22.782Z.