# NTSB NYC99LA148: Adams Rotorway EXEC-90, N8235W, Evington, VA, June 13, 1999

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: June 13, 1999, 09:30 local (13:30 UTC)
- Place: Evington, VA
- Coordinates: 37.229995, -79.279533 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=37.2300&lon=-79.2795&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report April 18, 2001
- Report: Approved by Office Director
- NTSB case key (mKey): 46599
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC99LA148
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/46599/pdf
- Page: https://openairdocs.org/ntsb/NYC99LA148

## Probable cause

The pilot's selection of unsuitable terrain for a run on landing. A factor was the dirt bank.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- On ground/water encounter with terrain/water, landing - roll
  - terrain condition - dirt bank/rising embankment (contributing factor)
  - unsuitable terrain or takeoff/landing/taxi area - selected, pilot in command (cause)

## Analysis

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.

## Factual narrative

On June 13, 1999, about 0930 Eastern Daylight Time, a homebuilt Rotorway Exec-90, a helicopter, N8235W, was substantially damaged while landing at a private helipad at Evington, Virginia.  The certificated private pilot was not injured.  Visual meteorological conditions prevailed for the local flight.  No flight plan was filed for the personal flight conducted under 14 CFR Part 91.

According to his written statement, the pilot was approaching to land, traveling through transnational lift.  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.

The pilot further stated that the engine may not have been developing full power.  Additionally, his neighbors told him that they observed smoke emanating from the engine.

On July 22, 1999, the engine was inspected and operated at the manufacturer's facility, in the presence of a Federal Aviation Administration Inspector.  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.

## Aircraft

- Registration: [N8235W](https://openairdocs.org/aircraft/N8235W), registered now, S/N 5041, built 1996 (OpenAirDocs)
- Reported make and model: Adams ROTORWAY EXEC-90 (ROTORWAY E)
- Registry model: [Adams Gary W ROTORWAY EXEC-90](https://openairdocs.org/model/adams-gary-w-rotorway-exec-90) (registry code 05628TL) (OpenAirDocs)
- Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs)
- Category: Helicopter, amateur-built
- Serial number: 5041
- Airframe hours: 82
- Engines: Rotorway RI-162 150 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Gary W. Adams
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Unknown, March 13, 1999, 7 hours before
- Departed: NONE
- Airport: NONE

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 37; private; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 110 total, 98 in this make and model, 46 as pilot in command, 7 in the last 90 days, 3 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: variable at 5 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 73 °F, dew point 63 °F
- Altimeter: 30.00 inHg
- Observed at: LYH, 7 nm away

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19990613006959A](https://openairdocs.org/incident/19990613006959A), Jun 13, 1999: Ebington, VA, Substantial damage. Exp. Rotorway executive helicopter rotor RPM dropped after take-off, and the acft struck a bump while trying to land and then rolled over onto its side, other…

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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