Section X
Safety Information
Symbol
VMCA
VSSE
VYSE
VXSE
~ft
Twin Engine (Piston)
Description
Airspeed below which directional con-
trol cannot be maintained
Airspeed below which an intentional
engine cut should never be made
Airspeed that will give the best single
engine rate-of-climb (or the slowest
loss of altitude)
Airspeed that will give the steepest
angle-of-climb with one engine out
AIR MINIMUM CONTROL SPEED
(VMCA)
VMCA is designated by the red radial on the airspeed indica-
tor and indicates the minimum control speed, airborne at
sea level.
YMCA
is determined by FAA regulations as the
minimum airspeed at which it is possible to recover direc-
tional control of the airplane within 20 degrees heading
change, and thereafter maintain straight flight, with not more
than 5 degrees of bank if one engine fails suddenly with:
• Takeoff power on both engines
• Rearmost allowable center of gravity
• Flaps in takeoff position
• Propeller windmilling in takeoff pitch configuration
However, sudden engine failures rarely occur with all factors
listed above, and therefore, the actual
VMCA in any particu-
lar situation may be a little slower than the red radial on the
airspeed indicator. Most airplanes with an inoperative eng-
ine
will not maintain level flight at maximum power at speeds
at or near
YMCA. Consequently, it is not advisable to fly at
speeds approaching
VMCA, except in training situations or
during flight tests. Adhering to the practice of never flying at
or below the published
VMCA speed for your airplane does
not eliminate loss of directional control as a problem in the
10-44
May, 1994
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