National Transportation Safety Board
Aviation Accident Final Report

 

 

Location:

Nelsonia, VA

Accident Number:

NYC04LA035

Date & Time:

11/16/2003, 1119 EST

Registration:

N999GC

Aircraft:

Northam RAF 2000

Aircraft Damage:

Destroyed

Defining Event:

 

Injuries:

1 Fatal

Flight Conducted Under:

Part 91: General Aviation - Personal

Analysis

The pilot was observed to initiate a takeoff in his homebuilt gyroplane, and then abort the takeoff.  He pulled clear of the runway, and held for about 10 minutes with the engine idling, after which he pulled onto the runway again, and took off.  He was next observed about 40 minutes later by a witness who reported that the nose of the gyroplane was oscillating up and down.  The oscillations steadied out and the gyroplane disappeared from the view of the witnesses.  Additional witnesses saw the gyroplane about 2 miles further long, still flying in the same direction.  Three of the witnesses reported the gyroplane was in straight and level fight when it rolled inverted, and descended to the ground.  One witness reported the gyroplane made a vertical climb, and reversed course to impact the ground.  The main rotor blades exhibited damage consistent with low rotor, and had struck the vertical stabilizer.  Marks were also found on the underside of the main rotor blades that were consistent with propeller contact.  Flight control continuity was not confirmed due to fire and impact damage.  The pilot's total flight experience was in excess of 14,550 hours, which included about 70 hours in make and model.

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
A loss of control for undetermined reason(s).

Findings

 

Occurrence #1: LOSS OF CONTROL - IN FLIGHT
Phase of Operation: MANEUVERING

Findings
1. (C) REASON FOR OCCURRENCE UNDETERMINED
----------

Occurrence #2: IN FLIGHT COLLISION WITH TERRAIN/WATER
Phase of Operation: DESCENT - UNCONTROLLED

Findings
2. TERRAIN CONDITION - OPEN FIELD

 

Factual Information

On November 16, 2003, at 1119 eastern standard time, a homebuilt RAF 2000 gyroplane, N999GC, was destroyed when it struck the ground in Nelsonia, Virginia.  The certificated airline transport pilot was fatally injured.  Visual meteorological conditions prevailed for the personal flight that originated from Accomack County Airport (MFV), Melfa, Virginia.  No flight plan had been filed for the local flight that was conducted under 14 CFR Part 91.

Personnel at the departure airport reported that the pilot had initiated a takeoff, and then aborted the takeoff for unknown reasons.  He pulled clear of the runway and stayed there for about 10 minutes with the engine idling.  He then pulled back on the runway and departed about 1028.  That was the last he was seen at the airport.

The gyroplane was next observed by a witness, who was located about 2 miles northwest of the accident site.  The witness reported that when she first observed the gyroplane, the nose was oscillating up and down.  The oscillations smoothed out, and the gyroplane continued in straight and level flight to the southeast.  Shortly after the gyroplane disappeared from view, she observed a rising column of black smoke coming from the direction the gyroplane was headed.

Additional interviews of witnesses in the area revealed that three of the witnesses reported that the gyroplane was in level flight when it rolled left to the inverted position, and then descended in a nose down attitude and impacted the ground.  One other witness thought that the gyroplane had first pitched up to a near vertical attitude, and then reversed course and impacted the ground in a nose down attitude.  The witnesses agreed that the gyroplane burst into flames after the impact.

The examination of the wreckage revealed that both main rotor blades had red paint transfer marks on the top and bottom side of the blades, 67 inches from the end of the blade straps, consistent with the location of the vertical stabilizer.  In addition, there were strike marks on underside of both blade tension straps, consistent with the location of the engine propeller.

One main rotor blade was straight, while the other was bent up about 20 degrees at the mid-span location.  There was no evidence of rearward bending of the blades.

A portion of the rudder was consumed in the fire.  However, the upper portion of the rudder was separated from the aircraft and found outside of the burn area.  There was impact damage on the left side of the separated piece.

The gyroplane was equipped with a fixed incident, horizontal stabilizer, which had winglets that were canted 20 degrees outboard of vertical.  The condition of the right winglet was consistent with a main rotor blade strike.

Flight control continuity was not confirmed due to impact and fire damage.

In addition, the main mast was separated below the rotor hub, and one propeller blade was found separated from the remainder of the blade.

Re-examination of the impact site revealed that all items found away from the main impact area were light items and subject to lateral movement from wind.  The direction of movement of the objects did not match the flight path described by witnesses.

The gyroplane had been modified with the addition of a fixed incident horizontal stabilizer.  This was not recommended by the kit manufacturer.  However, the experimental airworthiness certificate of the gyroplane did not preclude additions, deletions, or modifications from the original kit design.

The pilot was reported to have accumulated about 70 hours in make and model.  This included 20 hours of dual instruction in another RAF 2000, and then 50 hours in his own RAF 2000.

The pilot's flight experience was reported to be in excess of 14,550 hours.  He held ratings for airplanes single and multi-engine, and instrument airplane.  He did not posses a rotorcraft, gyroplane, category and class rating, nor was he required under existing rules from the Federal Aviation Administration (FAA).

Toxicological testing conducted by the FAA Toxicology Accident Research Laboratory, Oklahoma City, Oklahoma, revealed the following:

 17 mg/dl ethanol detected in urine

 2 mg/dl acetaldehyde detected in urine

 2 mg/dl n-propanol detected in urine

 86.36 ug/ml acetaminophen detected in urine

 452 ug/ml salicylate detected in urine

 No ethanol in lung

 No ethanol in brain

The toxicological report also noted that the samples were received in putrefied condition.

The toxicological report received from the State of Virginia reported an alcohol content of 0.01 percent ethanol by volume.  In addition, ethanol was not detected in vitreous fluid.

 

On November 18, 2003, an autopsy was conducted by Wendy Gunther, MD, Assistant Chief Medical Examiner, Tidewater District, State of Virginia.

According to the FAA-H-8083-21 Rotorcraft Flying Handbook, Chapter 21, Gyroplane Emergencies, pilot induced oscillations (PIO) can occur in both the longitudinal and lateral axis.  The publication further stated:

"...As with most other rotor-wing aircraft, gyroplanes experience a slight delay between control input and the reaction of the aircraft.  This delay may cause an inexperienced pilot to apply more control input than required, causing a greater aircraft response than was desired.  Once the error has been recognized, opposite control input is applied to correct the flight attitude. Because of the nature of the delay in aircraft response, it is possible for the corrections to be out of synchronization with the movements of the aircraft and aggravate the undesired changes in attitude.  The result is PIO, or unintentional oscillations that can grow rapidly in magnitude...."

"...the stability of a gyroplane is greatly influenced by rotor force.  If rotor force is rapidly removed, some gyroplanes have a tendency to pitch forward abruptly.  This is often referred to as a forward tumble, buntover, or power pushover.  Removing the rotor force is often referred to as unloading the rotor, and can occur if pilot-induced oscillations become excessive, if extremely turbulent conditions are encountered, or the nose of the gyroplane is pushed forward rapidly after a steep climb."

"A power pushover can occur on some gyroplanes that have the propeller thrust line above the center of gravity and do not have an adequate horizontal stabilizer.  In this case, when the rotor is unloaded, the propeller thrust magnifies the pitching moment around the center of gravity.  Unless a correction is made, this nose pitching action could become self-sustaining and irreversible. An adequate horizontal stabilizer slows the pitching rate and allows time for recovery."

"Since there is some disagreement between manufacturers as to the proper recovery procedure for this situation, you must check with the manufacturer of your gyroplane. In most cases, you need to remove power and load the rotor blades.  Some manufacturers, especially those with gyroplanes where the propeller thrust line is above the center of gravity, recommend that you need to immediately remove power in order to prevent a power pushover situation.  Other manufacturers recommend that you first try to load the rotor blades.  For the proper positioning of the cyclic when loading up the rotor blades, check with the manufacturer."

"When compared to other aircraft, the gyroplane is just as safe and very reliable.  The most important factor, as in all aircraft, is pilot proficiency.  Proper training and flight experience helps prevent the risks associated with pilot-induced oscillation or buntover...."

 

 

 

Pilot Information

Certificate:

Airline Transport; Flight Instructor; Commercial; Flight Engineer

Age:

51, Male

Airplane Rating(s):

Multi-engine Land; Single-engine Land

Seat Occupied:

Left

Other Aircraft Rating(s):

None

Restraint Used:

Seatbelt, Shoulder harness

Instrument Rating(s):

Airplane

Second Pilot Present:

No

Instructor Rating(s):

None

Toxicology Performed:

Yes

Medical Certification:

Class 1 Valid Medical--w/ waivers/lim.

Last FAA Medical Exam:

09/29/2003

Occupational Pilot:

 

Last Flight Review or Equivalent:

03/19/2003

Flight Time:

14550 hours (Total, all aircraft), 70 hours (Total, this make and model)

 

 

Aircraft and Owner/Operator Information

Aircraft Make:

Northam

Registration:

N999GC

Model/Series:

RAF 2000

Aircraft Category:

Gyroplane

Year of Manufacture:

 

Amateur Built:

Yes

Airworthiness Certificate:

Experimental

Serial Number:

H2-02-13540

Landing Gear Type:

Tricycle

Seats:

2

Date/Type of Last Inspection:

07/07/2003, Condition

Certified Max Gross Wt.:

1540 lbs

Time Since Last Inspection:

50 Hours

Engines:

1 Reciprocating

Airframe Total Time:

50 Hours at time of accident

Engine Manufacturer:

Subaru

ELT:

Not installed

Engine Model/Series:

EJ 22

Registered Owner:

On file

Rated Power:

130 hp

Operator:

On file

Operating Certificate(s) Held:

None

 

Meteorological Information and Flight Plan

Conditions at Accident Site:

Visual Conditions

Condition of Light:

Day

Observation Facility, Elevation:

WAL, 40 ft msl

Distance from Accident Site:

10 Nautical Miles

Observation Time:

1054 EST

Direction from Accident Site:

57°

Lowest Cloud Condition:

 

Visibility

10 Miles

Lowest Ceiling:

Overcast / 5000 ft agl

Visibility (RVR):

 

Wind Speed/Gusts:

9 knots /

Turbulence Type Forecast/Actual:

/

Wind Direction:

180°

Turbulence Severity Forecast/Actual:

/

Altimeter Setting:

30.23 inches Hg

Temperature/Dew Point:

14°C / 6°C

Precipitation and Obscuration:

 

Departure Point:

Melfa, VA (MFV)

Type of Flight Plan Filed:

None

Destination:

 (MFV)

Type of Clearance:

None

Departure Time:

1028 EST

Type of Airspace:

Class G

 

 

Wreckage and Impact Information

Crew Injuries:

1 Fatal

Aircraft Damage:

Destroyed

Passenger Injuries:

N/A

Aircraft Fire:

On-Ground

Ground Injuries:

N/A

Aircraft Explosion:

None

Total Injuries:

1 Fatal

Latitude, Longitude:

37.821667, -75.610278

 


 


Administrative Information

Investigator In Charge (IIC):

Robert L Hancock

Report Date:

09/01/2004

Additional Participating Persons:

Arthur Munns; Federal Aviation Administration; Richmond, VA

Publish Date:

 

Investigation Docket:

NTSB accident and incident dockets serve as permanent archival information for the NTSB’s investigations. Dockets released prior to June 1, 2009 are publicly available from the NTSB’s Record Management Division at pubinq@ntsb.gov, or at 800-877-6799. Dockets released after this date are available at http://dms.ntsb.gov/pubdms/.