NYC89FA073 · Grumman GA-7
Grumman GA-7 · Accident: in flight encounter with weather en route
From Lancaster Airport (LNS) to MBS International Airport (MBS)
Event
- NTSB case
- NYC89FA073
- 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
- 4 · 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
- Instrument Meteorological Cond
Grumman GA-7
- Aircraft type
- Grumman GA-7
- 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
- N115DS
- Operator
- David W. Sweigart · private individual
- Onboard fatalities
- Unknown
- Route
- From Lancaster Airport (LNS), Lancaster, PATo MBS International Airport (MBS), Saginaw, MI
- 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
- In flight encounter with weather
- 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
- Stall
- 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 › Airspeed, not maintained
- Pilot in command › Flight into known adverse weather, attempted
- Pilot in command › Stall, inadvertent
- Pilot in command › Weather forecast, disregarded
- Wing › Ice
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
AFTER RECEIVING A WEATHER BRIEFING FROM FSS THE PILOT DECIDED TO FLY INTO KNOWN ICING CONDITIONS WITH AN AIRCRAFT THAT WAS NEITHER CERTIFIED NOR EQUIPPED FOR FLIGHT INTO ICING CONDITIONS. THE AIRCRAFT WAS AT 6,100 FEET WHEN THE PILOT TOLD ATC THAT HE WAS PICKING UP ICE AND NEEDED A HIGHER ALTITUDE. HE WAS CLEARED TO 8,000 FEET. ACCORDING TO ATC RADAR DATA, THE AIRCRAFT REACHED 6,500 FEET, AND 12 SECONDS LATER IT WAS AT 3,500 FEET WHEN RADAR CONTACT WAS LOST. THE AIRCRAFT WAS SEEN IN A HIGH SPEED DIVE AT FULL POWER JUST PRIOR TO IMPACT WITH THE GROUND.
Probable cause
THE PILOTS DECISION TO DISREGARD THE WEATHER FORECAST AND ATTEMPT FLIGHT INTO KNOWN ICING CONDITIONS. AFTER THE WINGS STARTED TO ICE UP, THE PILOT INITIATED A CLIMB BUT COULD NOT MAINTAIN AIRSPEED AND INADVERTANTLY STALLED THE AIRCRAFT WHICH ENTERED AN UNCONTROLLED HIGH SPEED DESCENT TO THE GROUND.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record NYC89FA073
- Event ID
- 20001213X27647
- Case number
- NYC89FA073
- 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: 4171bc42725008d1ec7ec844be4faf7c6e0b8fa3532c3f72eb9de1eaf5f8ec7a; retrieved 2026-09-21T03:25:11.112Z.