Piper ARCHER II - Descent

SECTION
4
PIPER
AIRCRAFT
CORPORATION
NORMAL
PROCEDURES
PA-28-181,
ARCHER
II
Use
of
the
mixture
control
in
cruising
flight
reduces
fuel
consumption
significantly,
especially
at
higher
altitudes.
The
mixture
should
be
leaned
during
cruising
operation
above
5000
ft.
altitude
and
at
pilot’s
discretion
at
lower
altitudes
when
75%
power
or
less
is
being
used.
If
any
doubt
exists
asto
the
amount
of
power
being
used,
the
mixture
should
be
in
the
full
RICH
position
for
all
operations
under
5000
feet.
To
lean
the
mixture,
disengage
the
lock
and
pull
the
mixture
control
until
the
engine
becomes
rough,
indicating
that
the
lean
mixture
limit
has
been
reached
in
the
leaner
cylinders.
Then
enrich
the
mixture
by
pushing
the
control
towards
the
instrument
panel
until
engine
operation
becomes
smooth.
If
the
airplane
is
equipped
with
the
optional
exhaust
gas
temperature
(EGT)
gauge,
a
more
accurate
means
of
leaning
is
available
to
the
pilot.
Best
economy
mixture
is
obtained
by
moving
the
mixture
control
aft
until
peak
EGT
is
reached.
Best
power
mixture
is
obtained
by
leaning
to
peak
EGT
and
then
enrichening
until
the
EGT
is
100°F.
rich
of
the
peak
value.
Under
some
conditions
of
altitude
and
throttle
position,
the
engine
may
exhibit
roughness
before
peak
EGT
is
reached.
If
this
occurs,
the
EGT
corresponding
to
the
onset
of
engine
roughness
should
be
used
as
the
peak
reference
value.
Always
remember
that
the
electric
fuel
pump
should
be
turned
ON
before
switching
tanks,
and
should
be
left
on
for
a
short
period
thereafter.
In
order
to
keep
the
airplane
in
best
lateral
trim
during
cruising
flight
the
fuel
should
be
used
alternately
from
each
tank.
It
is
recommended
that
one
tank
be
used
for
one
hour
after
takeoff,
then
the
other
tank
be
used
for
two
hours;
then
return
to
the
first
tank,
which
will
have
approximately
one
and
one
half
hours
of
fuel
remaining
if
the
tanks
were
full
at
takeoff.
The
second
tank
will
contain
approximately
one
half
hour
of
fuel.
Do
not
run
tanks
completely
dry
in
flight.
The
electric
fuel
pump
should
be
normally
OFF
so
that
any
malfunction
of
the
engine
driven
fuel
pump
is
immediately
apparent.
If
signs
of
fuel
starvation
should
occur
at
any
time
during
flight,
fuel
exhaustion
should
be
suspected,
at
which
time
the
fuel
selector
should
be
immediately
positioned
to
the
other
tank
and
the
electric
fuel
pump
switched
to
the
ON
position.
4.29 DESCENT
NORMAL
To
achieve
the
performance
on
Figure
5-29
the
power
on
descent
must
be
used.
The
throttle
should
be
set
for
2500
RPM,
mixture
full
rich
and
maintain
an
airspeed
of
122
KIAS.
In
case
carburetor
ice
is
encountered
apply
full
carburetor
heat.
REPORT: VB-1120 ISSUED: JULY 2, 1979
4-18 REVISED: JULY 5, 1985