NYC99LA148 · Adams ROTORWAY EXEC-90 ROTORWAY E
Adams ROTORWAY EXEC-90 ROTORWAY E · Accident: on ground/water collision with terrain/water during landing
From No airport to an unrecorded destination
Event
- NTSB case
- NYC99LA148
- 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
Adams ROTORWAY EXEC-90 ROTORWAY E
- Aircraft type
- Adams ROTORWAY EXEC-90
- Category
- Helicopter
- 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
- N8235W
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From No airportTo 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
- Landing · landing roll
- 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
- On ground/water 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 › Unsuitable terrain or takeoff/landing/taxi area, selected
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot was approaching to land in his homebuilt helicopter. He was applying maximum power, but did not have sufficient rotor RPM. In an attempt to increase RPM, he lowered the collective, causing the helicopter to undershoot the intended landing point. The pilot could not touchdown at this point, because the field was at a 9 to 10 degree slope angle. Additionally, he did not have enough rotor RPM to hover up-slope. He made a 180 degree turn and flew down-slope. After the turn, the forward momentum plus the 1 to 2 knot headwind slightly increased rotor RPM. However, the pilot still did not have enough power to hover. He decided to perform a slide-on landing. During the landing, the right skid struck a mound of dirt, causing the helicopter to roll left. The main rotor blades struck the ground and tailboom. On July 22, 1999, the engine was inspected and operated at the manufacturer's facility. No interruptions, abnormalities, or discrepancies were found. The pilot reported a total flight experience of 110.5 hours, which 98.5 hours were in the accident helicopter. He received his private pilot license on December 4, 1998.
Probable cause
The pilot's selection of unsuitable terrain for a run on landing. A factor was the dirt bank.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record NYC99LA148
- Event ID
- 20001212X19100
- Case number
- NYC99LA148
- 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: c1ed0248c4c489286491986a1a147e08be68fe6101cf29adb10054eb2389f135; retrieved 2026-09-22T14:50:34.311Z.