Piper cherokee WARRIOR Pilots Operating Manual page 23

CHEROKEE WARRIOR
VACUUM SYSTEM*
The vacuum system is designed to operatc the air driven gyro instruments. l'his includes
t h c d i r c c t i o t t a l n r t d u t t i t u d c g y r o s w h c n i n s t a l l c d . T h e s y s t e m c o n s i s t s o f a n e n g i n e < l r i v e r r
\ l r c u u n l p t l n l l ) . i l v i r c u i l r n r c g t t l l r t r l r , i l l - i l t c r l r r r r l t l r c l l c c e s s i t r y l l l t u r t b i n g .
The vacuum pump is a dry' type pump whrclt eliminates the nced for an air/oil separator
and its plunrbing. A sltear drive protects the pump from damage. If the drive shears. thc'gyros
w i l l h e c o n r c i n o p e r r t i v c .
A vacuum gauge. mounted on the far right instrument panel provides a pilot check for the
system during operation. A decrease in pressure in a system that remained constant over an
extended period mav indicate a dirty filter. dirty screens, possibly a sticky vacuum regulator or
leak irt thc systent (a low vacuum indicator light is provided in the annunciator panel**). Zero
pressure would indicate a sheared pump dnve. detective pump, possibly a defective gauge or
collapsed line. In the c'vent of any gauge variation from the norm, the pilot should have a
mechanic check the system to prevent possible damage to the system components or eventual
failure of the system.
A vacuum regulator is provided in the system to protect the gyros. The valve is set so the
normal vacuurn reads 5.0 + .l inchc's of mercury, a setting which provides sufficient vacuum to
opcrate all the gyros at their rated RPM. Higher settings will damage the gyros and with a low
setting the gyros will be unreliable. The regulator is located behind the instrument panel.
INSTRUMENT PANEL
Thc instrument panel is designed to be firnctiorral and professional, accommodating
complete instruments and avionics equipment for VFR and IFR flights. A wide range of
optional instmments and avionics pennit an equipment selection to suit individual needs.
A natural scparation of the flight groul'r and power group is provided by placing the fligltt
group in the upper instrument panel and thc power group in the center and lower instrument
panels. The radios and the- circuit breakers are located on the upper and lower right panel
respective'ly. and havt' circuits provided for a complete line of optional radio equipment. An
engine cluster is located to tht-' right of the pilot control wheel and includes a fuel pressure
gauge. a rig}t and let't main fuel quantity gauge. an oil temperature gauge and an oil pressure
gallge.
Standard instruments on the Warrior panel include a compass, an airspeed indicator, a
tachometer. an altimeter, an ammeter, an engine cluster. and an annunciator panel**. The
conlpass is mounted to thc top of the instrument panel in clear view of the pilot. The
annunciator panel is mounted in the upper instrument panel to warn the pilot of a possible
nrall'unction in the alternator. oil pressure. or vacuum systems.
r \ r ' o t n ; l l t ' t c l t t t e < l l i l t s t r t n r r e n l o l l t i o u s u v r r i l u h l c l ' r l r t l r c p a n e l i r t c l r r d e s u s u c t i r ) n g a u g c ,
v t r l r t r r l s P 1 ' q ' 1 1 r r t t l i t r r l o t . r r l l r t t t t l t ' g y l o , t l i r t : c t i o r r ; r l
9 1 , r t - 1 .
c l o c k . t r u - s p c e i t l i l r d i c a t o r a n d a t u r n
r r r r t l s l i P i n t l i e u t o r o l t u r r r e o r l r u l i n a t o l ' .
- [ - l r c
a t t i t u d c g y r o a n c l d i r e c t i o n a l g y r o a r e v a c u u m
o p e r a t c d t h r o r r g l t t h e u s e o l a v u c u u m p u m p i n s t a l l c d o n t h e e n g i n e , w h i l e t h e t u r n a n d s l i p
i n d i c a t o r i s e l e c t r i c a l l y ' o p e r a t e d .
T h e v a c u u m s u c t i o n g a u g c i s o n t h e f a r r i g h t o f t h e i n s t r u m e n t
panel
*Optional equipment
* * S e r i a l n o s . 7 5 1 5 0 0 1 a n d u p
AIRPLANE AND SYSTEMS
REVISED: JUNE 14.1974
2 - t 3