SEA99LA079 · Snow S2C
Snow S2C · Accident: in flight collision with terrain/water during takeoff
Event
- NTSB case
- SEA99LA079
- 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
- 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
Snow S2C
- Aircraft type
- Snow S2
- 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
- N1665S
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From not recordedTo 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 137: Agricultural
- 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
- Takeoff
- 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 collision with terrain/water
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Pilot in command › Aircraft weight and balance, inaccurate
- Pilot in command › Altitude, inadequate
- Pilot in command › Load jettison, delayed
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot reported that after the airplane lifted off, it was not flying as well as it had on the previous six flights that morning. The pilot immediately opened the emergency dump which also controls the rate of application. The pilot reported that as he flipped the metal tab out of the way of the dump handle, the tab would not flip clear of the handle because of interference with the seat frame. The pilot was aware of this problem, however, he stated that he could hold the stop up with one finger and force the handle around the stop. The airplane continued to fly in ground effect as the pilot continued to try to dump the load. About one mile off the end of the airstrip, the airplane collided with a slight rise in the terrain. The pilot stated that he thought that he could have cleared the rise if he could have dumped the load more quickly. The type certificate data sheet for this aircraft indicates a gross weight of 4,400 pounds. The pilot reported that he was not aware of the requirement, and had not demonstrated the maximum set gross weight for the conditions to the FAA per Part 137 certification. The pilot reported that he estimated the weight of the load based on visual volume that had been previously weighed (approximately 1,000 to 1,100 pounds). The density altitude was estimated and determined to be approximately 5,684 feet at the time of the accident which utilized the pilot's estimated temperature. The weather reporting facility closest to the accident site reported a temperature 10 degrees warmer than the pilot's estimate. Utilizing the weather reporting facility, the density altitude would have been about 6,277 feet.
Probable cause
The pilot's inaccurate weight and balance calculations, and his delay in jettisoning the load which resulted in his failure to clear rising terrain. Contributing to the accident was the high density altitude, and the pilot's intentional operation with known deficiencies in equipment.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA99LA079
- Event ID
- 20001212X19111
- Case number
- SEA99LA079
- 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: 1efae97895f5235e63346c37fedef5557de324f334898243c27fb257651ff51d; retrieved 2026-09-22T15:00:17.536Z.