Airspeed Indicator - Piper Cherokee Six Service Manual

PIPER CHEROKEE SIX SERVICE MANUAL
TABLE IX-V. ALTIMETER (cont)
Cause
Trouble
Remedy
Altimeter sticks at
altitude or does not
change with change of
altitude.
Altimeter changes
reading as aircraft
is banked.
Altimeter requires
resetting frequently.
Water or restriction in
static line.
Water in static line.
Temperature compensator
inoperative.
Remove static lines
from all instruments,
blow line clear from
cockpit to pitot head.
Remove static lines
from all instruments.
and blow line clear from
cockpit to pitot head.
Change instrument.
NOTE
When. any connections in the static system are opened for
check, system must be rechecked per F.A.R. 23.1325.
9-33. REMOVAL AND REPLACEMENT. Refer to Paragraph 9-74 of
this section.
9-34. AIRSPEED INDICATOR.
9-35. GENERAL. The airspeed indicator provides a means of indicating
the speed of the
airplane passing through the air. The airspeed indication is the differential
pressure reading
between pitot air to pressure and static air pressure. This instrument
has the diaphragm
vented to the pitot air source and the case is vented to the static air
system. As the
airplane increases speed, the pitot air pressure increases, causing the diaphragm
to expand.
A mechanical linkage picks up this motion and moves the instrument
pointer to the
indicated speed. The instrument dial is calibrated in knots and miles per
hour, and also has
the necessary operating range markings for safe operation of the airplane.
INSTRUMENTS
Revised: 6/18/76
2K19