NTSB Identification: ERA10TA142
14 CFR Public Use
Accident occurred Thursday, February 11, 2010 in Cheverly, MD
Aircraft: EUROCOPTER As 365 N2, registration: N61MD
Injuries: 2 Uninjured.
This
is preliminary information, subject to change, and may contain errors.
Any errors in this report will be corrected when the final report has
been completed.
On February 11, 2010, about 2236 eastern
standard time, a Eurocopter AS 365 N2, N61MD, operated by the Maryland
State Police (MSP), was substantially damaged during a takeoff attempt
from the ground-level helipad at Prince George's General Hospital
(1MD4), Cheverly, Maryland. The commercial pilot and the pilot-rated
flight paramedic were not injured. The public medical evacuation flight
was being operated in night visual meteorological conditions, and no
flight plan was filed.
About 2112, the helicopter departed
Andrews Air Force Base (ADW), Camp Springs, Maryland, under visual
flight rules (VFR), in order to retrieve and transport two patients
from an automobile accident site to 1MD4. The helicopter landed at the
automobile accident site, the patients were loaded, and about 2200, the
helicopter departed for 1MD4. While enroute to 1MD4, the pilot was
advised by hospital personnel to land on the ground-level helipad, due
to the presence of ice on the hospital's elevated helipad.
According
to the pilot, due to noise abatement procedures and the reported winds
at ADW, he approached 1MD4 from the south-southeast. He stated that
when he was on final approach to the pad, he observed that it was clear
of snow, but that it had snow banks around the perimeter. He also noted
that a paved path was cleared of snow to allow the hospital receiving
team to access the helipad from the hospital building. The pilot stated
that during the final approach, he was concerned about creating "white
out" conditions (blowing snow which would restrict visibility) as the
helicopter neared the ground. In addition, he wanted to position the
helicopter so that the clearance between the snow banks and the front
of the helicopter would permit the receiving team to maneuver around
the helicopter.
The pilot stated that "the approach was made
to a high hover with straight let down," and that it "was completed to
the center of the ground pad to ensure safe clearance for the hospital
personnel to safely maneuver to unload the patients." The helicopter
landed about 2209, facing slightly south of west. The pilot stated that
"the landing...was accomplished with no incidents detected." After
landing, the flight paramedic and the hospital receiving team offloaded
and transported the patients to the hospital emergency department,
while the pilot shut down the helicopter. The pilot reported that the
shut down was normal, and after he secured the helicopter, he joined
the flight paramedic in the hospital.
About 2229, when the crew
returned to the helicopter, the pilot noted that "the crew observed
that the aircraft’s fenestron was resting on top of an approximate
three foot high snow bank," and that "further inspection detected no
damage to the fenestron." According to the flight paramedic, he
suggested to the pilot that it might be appropriate to remove some of
the snow beneath the fenestron, in order to provide more clearance for
the takeoff.
The pilot determined that "since there was no
damage" and that "the tail rotor itself was clear of the snow, a
straight up take off with no yaw movement would be made." About 2234,
engine start was completed, without any anomalies. The pilot stated
that "a slow deliberate takeoff was then initiated," and when the
helicopter "became light on the wheels, but prior to takeoff, a
vibration was detected, emanating from the rear of the aircraft." In
response to the vibration, the pilot lowered the collective, shut down
both engines, and applied the rotor brake.
The pilot stated that
after he shut down and secured the helicopter, he and the flight
paramedic visually inspected the helicopter. The pilot stated that the
inspection revealed that "the fenestron was found to be severely
damaged by the tail rotor blades, the right tail rotor gear box cap
appeared to have been ingested by the tail rotor, and numerous tail
rotor blades were damaged." Preliminary examination by MSP and Federal
Aviation Administration (FAA) personnel revealed substantial damage to
the tail rotor blades, the fenestron, the tail rotor gear box (TGB),
the TGB drive coupling, and the TGB mounting structure.
FAA
records indicated that the helicopter was manufactured in 1993, and
registered to the MSP in 1995. It was equipped with two Turbomeca Ariel
turboshaft engines, a single main rotor system, and a shrouded tail
rotor referred to as a "fenestron." The landing gear was retractable,
tricycle-style, with wheels and tires. Manufacturer's published
technical data indicated an overall length of 45.05 feet, fuselage
length of 38.15 feet, pilot's station about 32 feet forward of the
fenestron, and fenestron ground clearance of 2.17 feet.
FAA
records indicated that 1MD4 was equipped with two separate helipads;
one at ground level, designated "H1," and one on the hospital rooftop,
designated "H2." Helipad elevation was listed as 297 feet above mean
sea level. The helicopter used the H1 pad, which was 67 feet square,
and equipped with perimeter lights and a lighted wind indicator. The H1
pad was oriented about 10 degrees counter-clockwise from true
north-south alignment. The paved pad surface was black in color, and a
white stripe, approximately 2 feet wide, was painted around the entire
perimeter. Photographs taken the night of the accident showed that the
snow had been cleared to expose the majority of the perimeter stripe,
and was pushed into snowbanks that bordered all four sides of the pad.
The snowbanks ranged from 2 to 5 feet in height. The path that was
cleared through the snow between the pad and the hospital joined the
pad near the south end of the west edge.
FAA records indicated
that the pilot held a commercial pilot certificate with rotorcraft
helicopter and instrument helicopter ratings. His most recent FAA
second-class medical certificate was issued in June 2009. The MSP
reported that the pilot had 2,452 total hours of flight experience,
including 360 hours in the accident helicopter make and model. He had
25 hours in the helicopter make and model in the 90 days prior to the
accident, and 6 hours in the 30 days prior to the accident.
FAA
records indicated that the flight paramedic held a private pilot
certificate with several ratings, including rotorcraft helicopter.
The
2255 automated weather observation at ADW, located 7 miles south of
1MD4, recorded winds from 310 degrees at 9 knots, 10 miles visibility,
clear skies, temperature -2 degrees C, dew point -7 degrees C, and an
altimeter setting of 29.88 inches of mercury.Index for Feb2010 | Index of months
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