WHAT'S
GOING WITH ALL THESE KING AIR CRASHES?
Two deadly Beechcraft King Air accidents at the end of June helped propel
business aviation safety into one of its darkest periods. The fact that both
accidents occurred shortly after takeoff-and several recent similar
events-might be cause for alarm for this popular twin turboprop.
Combined, these two crashes-one in Hawaii, the other in Texas-accounted for 21
of the 57 business aviation fatalities during the first half of 2019. That's a
sixfold increase from the same period last year.
Since October 2014 there have been at least five King Air accidents during
takeoff or initial climb. During each of these events, including the two most
recent crashes, the pilot lost control of the aircraft shortly after takeoff.
In four of these events, the aircraft wreckage hit structures on or near an
airport.
Earlier this month, the NTSB released preliminary reports on the two most
recent crashes. Each report provides information related to each event and
signifies the beginning of an extensive investigation to determine probable
cause; the more conclusive final reports are typically published within 12
months of an accident.
In the first of the two fatal King Air accidents this year, a King Air A90
collided with terrain after takeoff from Dillingham Airfield in Mokuleia,
Hawaii. A commercial-rated pilot and 10 passengers were killed on this local
skydiving flight.
According to the preliminary report, a witness (employed by the operator)
stated he could hear "the engines during the initial ground roll and
stated the engines sounded normal, consistent with the engines operating at
high power." He then observed the aircraft at an altitude between 150 and
200 feet above ground level. It appeared to be turning and he could see the
belly of the airplane and the cabin facing the ocean to the north.
Shortly afterward, the aircraft "struck the ground in a nose-down
attitude, and a fireball erupted." The report continued that a preliminary
review of video from an airport surveillance camera revealed "that just
before impact, the airplane was in an inverted 45-degree nose-down
attitude."
On June 30, nine days after the Hawaii crash, a King Air 350 collided with a
hangar and terrain after takeoff from Addison Airport in Texas. Two pilots, one
an ATP and the other commercial-rated, and eight passengers died. The Part 91
cross-country flight was planned to depart Addison and fly to St. Petersburg,
Florida.
The NTSB is investigating the June 31 tragedy, which killed eight passengers
and two crewmembers.
According to the preliminary report, the takeoff and departure of the airplane
were captured by several video cameras and radar and observed by witnesses. One
witness stated that as the aircraft went down the runway, "it seemed
quieter than normal and sounded like it didn't have sufficient power to
takeoff."
After takeoff, witnesses observed the airplane drift to the left and then roll
to the left before colliding with the hangar. The report added that several
security cameras captured the drift to the left after takeoff and "one
camera showed the airplane roll completely inverted before it collided with the
hangar." The aircraft was equipped with a cockpit voice recorder. The report
stated that eight seconds before the end of the recording, a crewmember
commented on a problem with the left engine. Three seconds before the end of
the recording, three automated "bank angle" aural alerts were
recorded.
Final reports have been published on the other three takeoff events involving
King Airs-two in the U.S., the other in Australia. Examining each of these past
events might provide some hints of what happened in the most recent events. Of
interest: in each of these earlier cases, investigators cited pilot performance
as an issue rather than aircraft performance.
On Oct. 30, 2014, a King Air B200 crashed into a FlightSafety International
(FSI) simulator building at Wichita Eisenhower Airport (KICT). The ATP-rated
pilot was killed along with three people in the FSI facility; two others on the
ground received serious injuries. This flight was planned as a Part 91
repositioning flight from KICT to Mena, Arkansas.
During takeoff, the pilot declared an emergency and stated that the airplane
"lost the left engine." According to the report, the aircraft climbed
to about 120 feet above ground with its landing gear extended, continued a left
turn, and descended into the building.
Post-accident examination did not identify any anomalies with the airplane,
engines, or propellers that would prevent normal operation. It was determined
that the left engine was developing low to moderate power while the right
engine was developing moderate to high power. Neither propeller was feathered.
A "sideslip thrust and rudder study" completed by the NTSB determined
that during the last second of flight, the airplane had a nose-left side slip
of 29 degrees. The report concluded that the pilot likely applied substantial
"inappropriate" left rudder input (remember the pilot reported a
"lost" left engine) and failed to maintain lateral control of the
airplane. Other contributing factors included the pilot's failure to follow
emergency procedures-including feathering the propeller and retracting the
landing gear-for an engine failure.
On Jan. 23, 2017, a King Air 300 crashed shortly after takeoff in Tucson,
Arizona. The ATP-rated pilot and a passenger were fatally injured. According to
the NTSB final report, after takeoff the aircraft "reached an altitude of
about 100 to 150 feet above the runway in a nose-high pitch attitude, the
airplane rolled left to an inverted position as its nose dropped, and it
descended to terrain impact on the airport (coming to rest against a concrete
wall), consistent with an aerodynamic stall."
Post-accident examination of the aircraft found no evidence of preexisting
anomalies that would preclude normal operations. However, post-accident
toxicology testing of the pilot revealed the use of multiple psychoactive
substances that included over-the-counter, prescription, and illicit drugs. The
NTSB determined probable cause as "the pilot's exceedance of the
airplane's critical angle of attack during takeoff, which resulted in
aerodynamic stall. Contributing to the accident was the pilot's impairment by
the effects of a combination of psychoactive substances."
On Feb. 21, 2017, a King Air B200 crashed into a shopping mall seconds after
taking off from Essendon Airport in Melbourne, Australia. The charter flight
was scheduled to carry four American passengers to King Island to play golf;
all five people on board, including the Australian pilot, were killed in the
crash. An investigation by the Australian Transport Safety Board (ATSB)
determined that the accident was the result of a flight control trim tab being
set incorrectly before takeoff.
The ATSB could not identify any preexisting faults with the aircraft.
Investigators determined that the mis-set rudder trim caused a longer takeoff
roll and that once the airplane was airborne, this caused it to slip and yaw to
the left. After takeoff, the pilot made two "mayday" calls and
falsely identified the issue as an engine failure.
During the investigation, the ATSB also determined that the aircraft was above
its maximum allowable takeoff weight during the takeoff but did not cite this
weight discrepancy as a contributing factor.
Analysis of recent and past King Air accidents during takeoff and initial climb
suggest that each event is unique. All three accidents examined that have a
final report published identify specific pilot actions-use of the wrong rudder,
loss of control due to impairment, or a mis-set trim-as probable causes and
none identify any mechanical issues with the aircraft.
These pilot actions (other than the impaired pilot) can be mitigated through
better training or employing safeguards (such as checklists) to ensure that
items such as the trim is properly set. Not mentioned in either of the final
reports was the fact that these aircraft were flown single-pilot; of all the
accidents-only the Addison one had a pilot in the right seat.
A lack of familiarity or experience with an aircraft might have contributed to
one recent (Addison) and two past accidents (Wichita and Tucson); those events
involved either newly purchased aircraft or a "ferry" flight by a
contract pilot. In the past, the insurance industry has served as the "de
facto" regulator and has mandated minimum flight experience, recency, or
proficiency in type.
Following the most recent King Air accidents, there will be a lot of interest
when the NTSB publishes the respective final reports. From this brief analysis,
the airframe, engines, and propellers appear to be sound (7,500 examples have
been flying since the 1960s), but more intense scrutiny on the operators and
pilots (training, qualifications, and so on) might be in order.
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