Premium On Safety - Issue 17, 2015 - 6

LESSONS LEARNED
By the Book
BY DAVID JACK KENNY
reported seeing flames before
both the fire and the smoke
appeared to cease.
There was no response over
The natural impulse to return to the
field and land as quickly as possible
must be subordinated to the more
immediate emergency of simply
keeping the airplane flying.
In the fall of 2014, remarkably similar
accidents destroyed three twin-engine airplanes
in the space of two months. Each of
the pilots reported losing an engine immediately
after takeoff, then crashed while trying
to return to the airport. None survived.
In at least two, the landing gear was still
extended in the wreckage; the third report
doesn't specify.
While final determination of their causes
is probably still months away, all three
bear a strong resemblance to the fatal
crash of a Cessna 421C immediately after
takeoff from Sioux Falls, South Dakota, in
December 2011. The airplane was departing
for Rapid City on a Part 135 charter
flight with three passengers. Just over
one minute after clearing it for takeoff
on Runway 33, the controller advised the
pilot of "quite...a plume coming behind...
can't tell which motor it is," then added,
"Looks like it just stopped." Five witnesses
later confirmed that the left engine began
trailing white smoke, and three of them
6
the radio, but the airplane
began to turn left. Thinking
the pilot was trying to return
to the airport, the controller
cleared him to land. As the
twin Cessna came around to
a southerly heading, its nose
abruptly dropped, and the
airplane dove into the ground
from an altitude estimated
as 800 to 1,000 feet. A postimpact
fire began almost
immediately, consuming most
of the fuselage and parts of
both wings. No one on board
escaped.
Examination of the wreckage
determined that the left
engine's fuel selector had been
turned off, suggesting that the
pilot had shut it down after
becoming aware of the smoke.
However, the left propeller
had not been feathered. The
tachometer survived without
apparent damage; the left-engine needle
indicated 1,000 rpm while the right
showed about 2,250 rpm. Damage to the
right propeller likewise suggested that the
right engine was producing full power at
impact, while two of the left propeller's
three blades were essentially undamaged.
The landing gear remained down and
locked until it was collapsed by impact
forces, and the flaps were extended to
40 degrees.
Typical of most light twins, the Cessna
421C's emergency procedures checklist
for an engine failure after takeoff calls for
retracting the gear before attempting to
identify the faulty engine. That's considered
a memory item, one that the 3,850hour
commercial pilot-whose 1,320
hours of multiengine time included 360
in the C421-presumably knew by heart.
Next, the failed engine is identified, then
secured by closing the throttle and mixture
control and feathering the prop while
pitching for the best single-engine rateof-climb
speed of 111 knots and banking
five degrees toward the dead engine. The
remainder of the engine-securing checklist
(shutting off the fuel selector, magnetos,
alternator, etc.) can wait until the airplane's
been stabilized at a safe altitude.
Takeoffs are normally made with the flaps
retracted, so the fact that they were found
extended isn't readily explained.
There's some truth to the saying that
twins have two engines because they
need them. Even the most capable tend
to be marginal performers on a single
mill, and attaining anything close to book
performance depends on rigorous adherence
to the required procedures. Much of
multiengine training focuses on learning
to manage engine-out situations, of which
a power failure just after takeoff-when
full power on the good engine maximizes
asymmetry of thrust while low airspeed
diminishes the control authority available
to counter the resultant yaw and roll-is
among the most dangerous. The natural
impulse to return to the field and land as
quickly as possible must be subordinated
to the more immediate emergency of
simply keeping the airplane flying. That
requires cleaning it up completely: retracting
the gear and any flaps, feathering the
appropriate prop, and climbing straight
ahead at VYSE to pattern altitude. Only
after levelling off and, if possible, building
a little more airspeed is it safe to begin a
gentle turn to crosswind.
A common factor in all four of these
accidents-plus the horrific 2010 crash of
a Piper Seminole at West Palm Beach-is
that the pilots apparently tried to shortcut
that process by turning back before they'd
configured their airplanes for maximum lift
and minimum drag. The record suggests
that this particular emergency may warrant
more attention during recurrent training-whether
at altitude or in the simulator-and
that said training should stress
the importance of proceeding strictly by
the book.
David Jack Kenny is the Air Safety
Institute's statistician. He is a fixed-wing
ATP with commercial pilot privileges for
helicopters and the owner of a Piper Arrow.
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