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NTSB Identification: MIA00FA029 .
The docket is stored in the Docket Management System (DMS). Please contact
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14 CFR Part 91: General Aviation
Accident occurred Wednesday, November 24, 1999 in HELENA, AL
Probable Cause Approval Date: 4/18/2001
Aircraft: Hughes 369HS, registration: N395WM
Injuries: 2 Fatal.
The pilot called the FAA, Anniston FSS about 15 minutes before departure and requested a weather briefing for a flight from Montgomery to Birmingham. The pilot was told that there was an airmet in effect for instrument flight rules conditions from Birmingham northward and that visual flight rules flight was not recommended. The flight departed Montgomery at about 1855. About 1935, witnesses heard the helicopter flying from south to north at a low altitude, making ' a steady, loud, whining noise.' About 2-3 seconds later they heard a 'thump' crash sound and then heard no more sound from the helicopter. They went outside of their house and observed the fire from the wreckage of N395WM. The witnesses stated that at the time of the accident the weather was dark and slightly foggy. Post-crash examination of the wreckage showed the helicopter had impacted in a near nose down vertical descent, while on a 185-degree heading. All components of the helicopter, which are necessary for flight, were located on or around the main wreckage. A post-crash fire had consumed the fuselage of the helicopter. Examination of the remaining portions of the helicopter structure, flight controls, main and tail rotor systems, and engine showed no evidence of pre-crash failure or malfunction. Damage to the main rotor system and engine drive shaft was consistent with the engine and rotor system operating at the time of the accident.
The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The pilots continued visual flight rules flight into instrument meteorological conditions resulting in his becoming spatially disoriented and loosing control of the helicopter, which resulted in an uncontrolled descent and impact with the ground.
MIA00FA029
HISTORY OF THE FLIGHT
On November 24, 1999, about 1935 (all times central standard time), a Hughes
369HS, N395WM, registered to Vertical Air, Inc., crashed near Helena, Alabama,
while on a Title 14 CFR Part 91 business flight. Instrument meteorological
conditions prevailed at the time and no flight plan was filed. The helicopter
was destroyed and the commercial-rated pilot and one passenger were fatally
injured. The flight last departed Dannelly Field, Montgomery, Alabama, the same
day, about 1855.
A person identifying himself as the pilot of N395WM called the Federal Aviation
Administration (FAA), Anniston Automated Flight Service Station, at 1301:50,
stating he was visual flight rules from Birmingham to Montgomery, leaving around
1600, and flying in the area and coming back to Birmingham around 2000. The
pilot was told "the airmets for instrument flight rules do expire around three
o'clock today so it looks like you got a shot at that uh cold front pretty much
right on top of you right now drifting real slow to the east the progs do
indicate it's going to start to stall out here shortly though uh forecast for
Birmingham for that time frame calls for four thousand broken all the way
through ten pm tonight and Montgomery anywhere from three to five thousand
broken to scattered so looks pretty good for you." The briefing concluded at
1303:03. See transcripts of communications.
A person identifying himself as the pilot of N395WM called the FAA, Anniston
Automated Flight Service Station, at 1839:43, stating he was in Montgomery, and
would be leaving in the next 20 minutes, going toward Birmingham. The pilot was
told "we got clouds looks like rains a little bit off to the north and east of
your route of flight but ah with the front in the area it could be poppin up ah
we do have an airmet from Birmingham northward for instrument flight rules
conditions so visual flight rules not recommended but uh and right now
Birmingham is down they were clear below twelve earlier now they're calling it
eight hundred overcast with four miles in mist so they've dropped in a good bit
uh Montgomery is still clear below twelve with ten miles and calm." The pilot
was further told "the forecast is for cloud cover in the Birmingham area
generally to be uh fifteen hundred scattered occasional overcast another layer
at twenty five hundred feet six miles occasionally down to five light rain
showers and mist wind three forty at six and really that's as far south as the
airmet for instrument flight rules is right now." The pilot then asked "so if we
can get there in forty five fifty minutes we might be okay." The weather briefer
replied "right and if you do need to get back into visual flight rules
conditions head south." The briefing ended at 1841:28. See transcripts of
communications.
A line serviceman for Montgomery Aviation, at Dannelly Field, Montgomery,
Alabama, stated that N395WM arrived on the ramp with the pilot in the left front
seat and the passenger in the right front seat. The pilot asked that he fuel the
helicopter by adding 30 gallons of Jet-A fuel. The pilot also stated he was in a
hurry because the weather was getting bad and the ceilings were going down.
At 1850:51, the pilot of N395WM called the local controller at the FAA,
Montgomery Air Traffic Control Tower, stating "we're over at ah Montgomery
Aviation we're ready to depart ah toward ah the city and up sixty five to
Birmingham." At 1854:35, the flight was cleared for takeoff on taxiway alpha
with a left turn out. At 1855:46, the pilot was told to contact the FAA,
Montgomery Departure Control. The pilot made contact with the departure
controller, and when asked what his destination was, the pilot responded Shelby
County. At 1915:47, the departure controller stated to the pilot that radar
service was terminated, squawk visual flight rules code, and frequency change
approved. The pilot did not respond to this transmission. See transcripts of
communications.
Recorded radar data from the FAA, Montgomery Approach Control, showed that after
takeoff, the flight climbed to 1,800 feet msl, and flew a north-northwest
heading. The flight was last observed on the Montgomery Approach Control radar
at 19:14:27, while at a bearing of 335 degrees at 26 nm from Montgomery, at an
altitude of 1,800 feet, on a heading of 327 degrees, and at a ground speed of
107 knots. See radar data.
Witnesses located in a house near the crash site stated that shortly after 1930,
they heard the helicopter fly over their house at a very low altitude, from
south to north, making a steady, loud, whining noise. About 2-3 seconds later
they heard a "thump" crash sound and then heard no more sound from the
helicopter. They went outside and observed the fire from the helicopter wreckage
on the hill to the north of their house. They stated the weather at the crash
site was dark and slightly foggy.
PERSONNEL INFORMATION
The pilot held a FAA commercial-pilot certificate, with a rotorcraft-helicopter
rating, last issued on December 30, 1993. The pilot held a FAA second-class
medical certificate, with no limitations, issued on January 20, 1999. The
pilot's wife stated he lost his pilot logbook in 1996, and started a new logbook
at that time. She further stated that he carried his pilot logbook with him when
he flew the helicopter and that it would have been destroyed in the post crash
fire. The pilot reported on his application for his second-class medical
certificate on January 20, 1999, that he had 680 total flight hours, and had
flown 45 flight hours in the previous six months. A flight instructor reported
to NTSB that he had given the pilot a biennial flight review on January 15,1999.
The pilot completed an aircraft standardization course for the McDonnell-Douglas
model 500 helicopter, conducted by the University of North Dakota, on May 15,
1999. According to the University of North Dakota, the pilot was not signed off
for a biennial flight review after the training. See University of North Dakota
records.
AIRCRAFT INFORMATION
The helicopter was a Hughes model 369HS. Maintenance records showed the
helicopter had accumulated 5,483 total flight hours at the time of the accident.
The helicopter was last inspected on May 17, 1999, 97 flight hours before the
accident, when it received an annual inspection. See maintenance records.
METEOROLOGICAL INFORMATION
The National Weather Service, Surface Analysis Chart for 1800 indicated a cold
front extending from the northeastern United States through western North
Carolina, northwestern Georgia, and southeastern Alabama into the Gulf of
Mexico. Station plots on the chart showed mostly overcast cloud conditions west
of the front over Alabama, Mississippi, and Tennessee. In addition, the station
plots indicated northerly-northwesterly winds, diminishing temperatures, and
patchy restricted visibilities west of the front.
The Alabaster-Shelby County Airport, 1953 surface weather observation was winds
340 degrees at 5 knots, visibility 6 miles, mist, few clouds at 1,000 feet,
temperature 64 degrees F, dew point temperature 62 degrees F, altimeter setting
30.11 inches hg. Alabaster-Shelby County Airport is located about 9 miles
east-southeast of the accident site.
The Birmingham International Airport, 1953 surface weather observation was winds
350 degrees at 8 knots, visibility 2 miles, mist, clouds 800 feet overcast,
temperature 57 degrees F, dew point 66 degrees F, altimeter setting 30.13 inches
hg. The Birmingham International Airport is located about 20 miles
north-northeast of the accident site.
Sun and Moon data show that at the time and location of the accident the sun was
at an altitude of -35.4 degrees on a 268-degree bearing. The moon was at an
altitude of 14 degrees, on a bearing of 75.8 degrees, and had a 95 percent
illumination. See NTSB Meteorological Group Chairman Factual Report.
Witnesses near the accident site stated the weather was dark and slightly foggy
at the time of the accident.
COMMUNICATIONS
At the time of the accident there were no known contacts with the pilot by
ground persons. Personnel from Dent Aviation at the Shelby County Airport stated
they were closed at the time of the accident and there would not have been
anyone at the airport to answer the radio set to the airport Unicom frequency.
The last known contact with the pilot was at 1902, when the pilot communicated
with the departure controller at the FAA Montgomery Approach Control. See
transcripts of communications.
WRECKAGE AND IMPACT INFORMATION
The helicopter crashed in a wooded area to the northeast of a house located at
2680 Coalmont Road, Helena, Alabama. The accident site was on a 30-degree sloped
hill. Examination of the accident site indicated the helicopter crashed while in
a near vertical, nose down descent. The 60 to 70 foot tall trees above the
impact point had very little branch damage. The final impact heading was about
185 degrees. All components of the helicopter necessary for flight were located
on or around the main wreckage. Wreckage was scattered over a 75 feet long by 30
feet wide area, which extended from the main wreckage and impact point, westerly
down the sloped terrain. A postaccident fire had erupted and consumed the main
wreckage.
The forward portion of the left and right landing gear skids were found embedded
in the ground about 90 degrees downward from the normal direction of flight,
which is perpendicular to the ground. The skid portions were about 7.5 feet
apart. The cockpit, cabin area, main rotor transmission, and main transmission
were located about 10 feet to the south of the embedded front portion of the
landing gear skids. The engine was located about 12 feet downhill, toward the
west, from the initial impact point. The tailboom, with tail rotor gearbox, tail
rotor hub assembly and blades, and the vertical and horizontal stabilators
attached, was located about 25 feet downhill, toward the west, from the initial
impact point. One main rotor blade was located about 75 feet downhill, toward
the west, from the initial impact point.
Examination of the cockpit, cabin, and fuselage area showed they were completely
consumed by fire. Examination of the tailboom indicated it had separated from
the fuselage due to overload compression. The horizontal and vertical
stabilators had ground impact damage. The tail rotor blades showed no rotational
damage. The tail rotor pitch change assembly and drive assembly operated
normally after the accident. The tail rotor drive shaft had separated at the
point the tail boom separated from the fuselage, due to overstress.
Examination of the main rotor transmission and rotor system showed the
transmission and rotor head rotated freely. The main rotor head and main rotor
blades showed evidence of extensive rotational damage. One main rotor blade
separated during ground impact due to overload fractures of the strap pack
laminates. The upper main rotor system flight controls showed evidence of
multiple overstress fractures and bends typical of a power on condition during
sudden stoppage.
Examination of the engine to transmission drive shaft showed overload fractures
due to sudden stoppage. The overrunning clutch showed normal wear when examined
after the accident.
The engine sustained extensive ground impact and post-crash fire damage.
Post-crash examination of the engine did not evidence any internal or external
failures that were not a result of ground impact and postcrash fire damage. See
Boeing Helicopter and Rolls-Royce reports.
MEDICAL AND PATHOLOGICAL INFORMATION
Dr. Stephen Pustilnik, State Medical Examiner, Birmingham, Alabama, performed
postmortem examination of the pilot and passenger. The cause of death for each
was attributed to multiple blunt force trauma. No findings that could be
considered causal to the accident were reported. Postmortem toxicology tests
were performed on specimens obtained from the pilot by Dennis V. Canfield,
Ph.D., Manager, Toxicology and Accident Research Laboratory, Federal Aviation
Administration, Oklahoma City, Oklahoma. The tests were positive for ethanol,
acetaldehyde, and n-butanol in muscle. These findings were attributed to
postmortem ethanol formation. The tests were negative for drugs.
ADDITIONAL INFORMATION
The aircraft wreckage was released by NTSB on November 27, 1999, to Tom Dilbeck,
Claims Representative, AIG Aviation, Inc. Components retained by NTSB for
further examination were returned to Atlanta Air Salvage, Griffin, Georgia.
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