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action is taken in the event of an engine failure. The
pilot should be thoroughly familiar with the airplane’s
performance capabilities and limitations in order to
make an informed takeoff decision as part of the preflight
planning. That decision should be reviewed as
the last item of the “before takeoff” checklist.
In the event of an engine failure shortly after takeoff,
the decision is basically one of continuing flight or
landing, even off-airport. If single-engine climb
performance is adequate for continued flight, and
the airplane has been promptly and correctly configured,
the climb after takeoff may be continued. If
single-engine climb performance is such that climb
is unlikely or impossible, a landing will have to be
made in the most suitable area. To be avoided above
all is attempting to continue flight when it is not
within the airplane’s performance capability to do
so. [Figure 12-6]
Takeoff planning factors include weight and balance,
airplane performance (both single and multiengine),
runway length, slope and contamination, terrain and
obstacles in the area, weather conditions, and pilot
proficiency. Most multiengine airplanes have
AFM/POH performance charts and the pilot should
be highly proficient in their use. Prior to takeoff, the
multiengine pilot should ensure that the weight and
balance limitations have been observed, the runway
Ch 12.qxd 5/7/04 9:54 AM Page 12-8
length is adequate, the normal flightpath will clear obstacles
and terrain, and that a definitive course of action has
been planned in the event of an engine failure.
The regulations do not specifically require that the
runway length be equal to or greater than the accelerate-
stop distance. Most AFM/POHs publish
accelerate-stop distances only as an advisory. It
becomes a limitation only when published in the
limitations section of the AFM/POH. Experienced
multiengine pilots, however, recognize the safety
margin of runway lengths in excess of the bare minimum
required for normal takeoff. They will insist
on runway lengths of at least accelerate-stop distance
as a matter of safety and good operating
practice.
50 ft
Brake VR / VLOF
Release
Accelerate-Stop Distance
Accelerate-Go Distance
500 ft
Brake VLOF
Release
5,000 ft
10:1 or 10 Percent Climb Gradient
Figure 12-5. Accelerate-stop distance, accelerate-go distance, and climb gradient.
Figure 12-6. Area of decision.
12-9
VXSE
VYSE
Gear Up and Loss of One Engine
Best Rate of Climb
Best Angle of Climb
Decision Area
VR / VLOF
Brake
Release
ENGINE FAILURE AFTER LIFT-OFF
Ch 12.qxd 5/7/04 9:54 AM Page 12-9
The multiengine pilot must keep in mind that the
accelerate-go distance, as long as it is, has only
brought the airplane, under ideal circumstances, to a
point a mere 50 feet above the takeoff elevation. To
achieve even this meager climb, the pilot had to instantaneously
recognize and react to an unanticipated
engine failure, retract the landing gear, identify and
feather the correct engine, all the while maintaining
precise airspeed control and bank angle as the airspeed
is nursed to VYSE. Assuming flawless airmanship thus
far, the airplane has now arrived at a point little more
than one wingspan above the terrain, assuming it was
absolutely level and without obstructions.
With (for the purpose of illustration) a net 150 f.p.m.
rate of climb at a 90-knot VYSE, it will take approximately
3 minutes to climb an additional 450 feet to reach
500 feet AGL. In doing so, the airplane will have
traveled an additional 5 nautical miles beyond the
original accelerate-go distance, with a climb gradient
of about 1.6 percent. Aturn of any consequence, such
as to return to the airport, will seriously degrade the
already marginal climb performance.
Not all multiengine airplanes have published accelerate-
go distances in their AFM/POH, and fewer still
publish climb gradients. When such information is
published, the figures will have been determined under
ideal flight testing conditions. It is unlikely that this
performance will be duplicated in service conditions.
The point of the foregoing is to illustrate the marginal
climb performance of a multiengine airplane that
suffers an engine failure shortly after takeoff, even
under ideal conditions. The prudent multiengine
pilot should pick a point in the takeoff and climb
sequence in advance. If an engine fails before this point,
the takeoff should be rejected, even if airborne, for a
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