EMB-120 Pressurização

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FlightSafety internatinnal & EMB-120 PILOT TRAINING MANUAL CHAPTER 12 PRESSURIZATION INTRODUCTION The EMB-120 pressurization system provides crcw and passengcr comfort and survival through- out thc cntirc aircraft opcrating envelope. Pressurization is achicvcd and controllcd using outflow valves to restrict the air-conditioning system airflow exiting the cabin. GENERAL Thc pressurization system is designed to maintain the cabin altitude at a comfortable and safe levei for the passengers and crew. The system is capable of maintaining a sca-lcvcl cabin to 16,800 feet, and an 8,000-foot cabin at 32,000 feet. Normal cabin differential pressure is 7 psi. Cabin outflow is controlled by an electropneumatic and a pneumatie outflow valve. Thc pressurization system may be operated in two modes: auto- matic or manual. In the automatic mode, the elcctropncumatic outflow valvc is used, with the pneumatie outflow valve slaved to it. In the manual mode, the electropneumatic outflow valve is closcd, and cabin outlet flow is controllcd only by the pneumatie outflow valve. Both outflow valves are located in the center of the rear pressure bulkhead inside the pressurized cabin. They are each capable of maintaining the proper cabin pressure independently. Air is directed into the cockpit and the passenger cabin through the air conditioning distribution system. Air- flow from the cockpit exits through an air sump exhaust in the cockpit floor, and airflow from the passenger cabin exits through foot-level grills. Revision 2 FOR TRAINING PURPOSES ONLY 12-1

description

aeronave Brasilia

Transcript of EMB-120 Pressurização

FlightSafety i n t e r n a t i n n a l &

E M B - 1 2 0 PILOT TRAINING M A N U A L

CHAPTER 12 PRESSURIZATION

INTRODUCTION T h e E M B - 1 2 0 p r e s s u r i z a t i o n s y s t e m p r o v i d e s c r c w a n d p a s s e n g c r c o m f o r t a n d su rv iva l t h r o u g h -ou t t h c c n t i r c a i r c r a f t o p c r a t i n g e n v e l o p e . P r e s s u r i z a t i o n i s a c h i c v c d a n d c o n t r o l l c d u s i n g o u t f l o w v a l v e s t o r e s t r i c t t h e a i r - c o n d i t i o n i n g s y s t e m a i r f l o w e x i t i n g t h e c a b i n .

GENERAL T h c pressurizat ion sys tem is des igned to main ta in the cabin altitude at a comfortable and safe levei for the passengers and crew. T h e sys tem is capable of maintaining a sca-lcvcl cabin to 16,800 feet, and an 8 ,000 - foo t cab in a t 32 ,000 fee t . N o r m a l cab in differential pressure is 7 psi.

Cabin outflow is controlled by an electropneumatic and a pneumat ie outf low valve. Thc pressurization s y s t e m m a y b e o p e r a t e d i n two m o d e s : a u t o -m a t i c o r m a n u a l . I n t he a u t o m a t i c m o d e , t h e e l cc t ropncumat i c ou t f low valvc i s used , wi th t he pneumatie outflow valve slaved to it. In the manual m o d e , t he e l e c t r o p n e u m a t i c o u t f l o w v a l v e i s

closcd, and cabin outlet f low is control lcd only by the p n e u m a t i e ou t f low valve .

Both outf low valves are located in the center of the rear pressure bulkhead inside the pressurized cabin. They are each capable of maintaining the proper cabin pressure independently.

Air is directed into the cockpit and the passenger cabin through the air conditioning distribution system. Air-f low f r o m the cockpit exits through an air s u m p exhaust in the cockpi t f loor, and a i r f low f r o m the passenger cabin exits through foot-level grills.

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FlightSafety I n t e r n a t i o n a l *

STATIC P O R T S

APU B L E E D

C O N D I T I O N E D AIR

T R I P L E INDICATOR

T l •

CABIN P R E S S U R E

CABIN P R E S S U R E

S E N S O R

CABIN P R E S S U R E

AIR FILTER

R A T E O F CLIMB S E L E C T O R

CABIN ALTITUDE S E L E C T O R

E L E C T R O N I C C O N T R O L L E R

B A R O M E T R I C C O R R E C T I O N

S E L E C T O R

M O D E S E L E C T O R

S W I T C H

P O W E R S L E V E R S S W I T C H

CABIN P R E S S U R E

MANUAL P A N E L

S E L E C T O R

a

MANUAL C O N T R O L L E R

CABIN ALTITUDE LIMITATION

CABIN P R E S S U R E

N E G A T I V E

P R E S S U R E R E L I E F

CABIN P R E S S U R E

O V E R P R E S S U R E R E L I E F

P N E U M A T I C R E L A Y \

CABIN P R E S S U R E

N E G A T I V E P R E S S U R E R E L I E F \

R E F E R E N C E P R E S S U R E

LANDING G E A R

S W I T C H

V A C U U M

CABIN P R E S S U R E

O V E R F L O W P R E S S U R E R E L I E F

E N G I N E B L E E D

LEGEND | CABIN P R E S S U R E

~ ~ | H G H - P R E S S U R E B L E E D AIR

| C O N T R O L P R E S S U R E

~ ~ | S T A T ' C P R E S S U R E

~ ~ | R E F E R E N C E P R E S S U R E

JET PUMP

STATIC P R E S -S U R E

STATIC P R E S -S U R E

Figure 12-1. Pressurization System Schematic

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E M B - 1 2 0 PILÜT TRAINING M A N U A L

F R O N T P R E S S U R E BULKHEAD

NORMAL V E N T S (TYPICAL)

O U T F L O W VALVES (2)

REAR P R E S S U R E BULKHEAD

LEGEND ] P R E S S U R I Z E D

] U N P R E S S U R I Z E D

Figure 12-2. Pressurized Areas

T h e ai r f low f r o m the cockpi t and passenger cabin produces an underf loor flow. This f low is partially recirculated by fans and partially exhausted over-board th rough the out f low valvcs.

C O M P O N E N T S The pressurization system consists oi" lhe fol lowing componen t s (Figure 12-1):

• E lec t ropneumal ie out f low valve

• P n e u m a t i e out f low valve

• E jee to r je t p u m p

• Blowout paneis

ELECTROPNEUMATIC OUTFLOW VALVE T h e e lec t ropneumat ic out f low valve, localed in the rear pressure bulkhead, eontrols the outf low of air f r o m the a i rp lane ' s p re s su r i zed zone to the cabin exterior through the unpressur ized lail cone (Figure 12-2).

T h e e lec t ropneumat ic outf low valve operates only when the pressurizat ion sys tem is in the au tomat ic mode. It is operated electrically by a torque motor that is control led by the electronic controller.

The diaphragm chamber of the electropneumatic out-flow valve is connected to the d iaphragm chamber of the pneumatie outflow valve. Therefore, when the e lec t ropneumat ic out f low valve is operat ing, the p n e u m a t i e o u t f l o w va lve i s a lso opera t ing and slaved to it.

The electropneumatic outflow valve is equipped with the fo l lowing safe ty devices:

• Overpressur izat ion relief valve

• Negat ive-pressure relief valve

• Cabin al t i tude l imiter

Overpressure Relief Valve An overpressure relief valve is built into the elec-tropneumatic outflow valve. It senses both cabin and static pressures . W h e n the p ressure d i f fc rent ia l be tween the two reaches 7.2 psid, i t opens the out -f low valve to relieve the excess cabin pressure.

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Negat ive-Pressure Relief Valve A ncgativc-prcssurc relief valve is also built into the electropneumatic outflow valve. When the pressure different ial exceeds - 0 . 3 psid, the valve opens to cqual izc thc cabin pressure.

Cabin Altitude Limiter T h c cabin al t i tude l imiter is only on thc c lcctrop-neumatic outflow valve. When cabin altitude reach-es approximately 13,000 feet, the limiter closes the e lcc t ropncumat ic ou t f low valve (and thc slavcd pneumatie outflow valve), limiting further cabin climb. The cabin altitude will be maintained at 13,000 feet only if the packs are operat ing.

If the cabin is depressurized in the manual mode of operation, there is no limitation on how high the cabin will cl imb.

PNEUMATIC OUTFLOW VALVE Thc pneumatie outflow valve, locatcd next to thc elec-t ropneumat ic out f low valve in the rear pressure bulkhead , opera tes independent ly only when the manua l m o d e of operat ion is seleeted. Othcrwisc , it is slaved to the e lec t ropneumat ic out f low valve.

T h e pneumat ie outf low valve is physical ly similar to the e lec t ropneumat ic valve except that it uses a pneumat ie relay (actuated by pressure differential) rather than a torque motor (powered electrically) for operat ion.

T h e pneumat ie outf low valve is equipped with the fo l lowing safe ty devices:

• Overpressur iza t ion relief value

• Ncgat ivc-prcssurc relief value

Overpressure Relief Valve Like thc electropneumatic outf low valve, thc pneu-mat ie ou t f low valve has an ove rp re s su re relief valve that opens w h e n the pressure d i f ferent ia l rcachcs 7.2 psid.

Negat ive-Pressure Relief Valve As on the electropneumatic outf low valve, the neg-ative-pressure relief valve on the pneumatie outflow valve opens to equalize the cabin pressure when the pressure differential exceeds - 0 . 3 psid.

EJECTOR JET PUMP An ejector jet pump , operated by engine bleed-air pressure, creates the vacuum supplied to the manual controllcr and used for control of the outflow valves.

An additional ejector jet pump is included when an A P U is installcd.

BLOWOUT PANELS B l o w o u t pane i s a re ins ta l led to equa l i ze e x c e s -s ive p r e s s u r e d i f f e r e n t i a l s b e t w e e n t he p r e s -s u r i z e d c o m p a r t m e n t s .

In the event of a rupture of the pressure vessel , the blowout paneis prevent structural damage to the air-craf t by provid ing quick equalizat ion of pressure be tween the var ious pressur ized zones.

T h e blowout paneis are located in the fo rward and aft partit ions, aft pressure bulkhead lining, cockpit flooring, and under the skirting panei (Figure 12-2).

T h e cargo c o m p a r t m e n t has an equal izer valve installed. It actuates in both directions, maintaining the same pressure in the cargo compartment and the cabin.

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A U T O

CABIN

E M E R G / P A R K P R A K E

Figure 12-3. Pressurization Control Panei

C O N T R O L A N D MONITORING The controls and indicator for the pressurization sys-tem are located on the center pedestal be tween the pilots (Figure 12-3).

T h e con t ro l s , u sed to ope ra t e the two o u t f l o w valves, are:

• M o d e selector switch

• Electronic control ler

• Manua l control ler

Ali of the pressurizat ion indications are displayed on a triple indicator.

MODE SELECTOR SWITCH T h e func t ions of the three-posi t ion m o d e selector switch (Figure 12-3) are as fol lows:

• AUTO—Selects the automatic mode of oper-ation. The electronic controller operates the e lec t ropneumat ic out f low valve which , in tum, drives the slaved pneumatie outflow valve.

• M A N — S e l e c t s the manua l m o d e of opera-t ion. T h e manual control ler provides inputs to the pneumat ie out f low valve only.

• D U M P — ( S a f e t y g u a r d mus t be l i f t e d . ) Rapidly depressur izes the aireraft by open -ing both outflow valves. Cabin rate of c l imb is a p p r o x i m a t e l y 14,400 feet per minu te ( fpm) . Al t i tude l imiter limits cabin alt i tude to approximate ly 13,000 feet .

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Figure 12-4. Electronic Controller

ELECTRONIC CONTROLLER T h e electronie control ler (Figures 12-3 and 12-4) is used in conjunction with the AUTO mode. It elec-trically controls thc clcctropncumatic outflow valve through the to rque motor.

Paramctcrs for operat ing thc pressurization sys tem i in the A U T O m o d e may be preset us ing the three knobs and scales on the electronic controller:

• ALT knob and scales

• R A T E knob

• B A R O knob and scale

ALT Knob and S c a l e s T h e ALT knob on the electronic controller (Figure 12-4) rotates thc nccdlc on thc instrument to seleet:

• Cabin al t i tude on the outer C A B I N scale ( - 1 , 5 0 0 to 10,000 feet) , or

• Airplane flight levei on the inner FLIGHT ALT scale

T h e lixed scales display the re la t ionship be tween cabin altitude and aireraft altitude at the normal oper-ating pressure differential of 7 psid. For example : 0 cabin altitude (outer scale) corresponds to approx-imatcly 17,000 feet a i reraf t al t i tude ( inner scale), and 8,000 feet cabin altitude corresponds to approx-imately 32 ,000 feet aireraft alti tude.

RATE Knob T h e R A T E knob selecls the cabin rale of c l imb or dcsccnt in thc A U T O mode .

Normal Cabin Climb Rate T h e d e t e n t p o s i t i o n o f t h e R A T E k n o b s e t s 650 f p m cabin rate of c l imb or 450 f p m cabin rate of descent . This is the bes t c o m p r o m i s e be tween passenger comfor t and t ime fo r cabin cl imb and descent dur ing normal operat ions.

Maximum Cabin Climb Rate The fully clockwise position of the RATE knob sets 1,450 f p m cabin rate of c l imb or 1,000 f p m cabin rate of descent .

Minimum Cabin Climb Rate T h e ful ly counterc lockwise posit ion of the R A T E knob sets 200 f p m cabin rate of c l imb or 150 f p m cabin rate of descent .

BARO Knob and S c a l e T h e B A R O (baromet r ic ) knob ad jus t s the e lec-tronic controller between 29.00 and 31.00 inches Hg. T h e B A R O S E T scale is located at the 10 o ' c lock position of the inner scale on the electronic controller (Figure 12-4).

MANUAL CONTROLLER The manual controller (Figure 12-5) pneumatical ly controls the pneumat ie out f low valve during oper -ation i n thc M A N mode . The M A N m o d e should be used only in the event of an electrical power failure o r A U T O m o d e failure.

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W h e n an A U T O m o d e fai lure oceurs, the manua l control ler knob should be placcd in the l o ' c lock posi t ion be fo re swi tching the m o d e selector f r o m A U T O t o M A N .

T h e c o n t r o l l e r s e l e c t s v a r i a b l e c a b i n c l i m b o r d e s c e n t r a t e s b e t w e e n 2 , 5 0 0 f p m ra te o f c l i m b ( U P p o s i t i o n ) a n d 1 , 5 0 0 f p m r a t e o f d e s c e n t ( D N p o s i t i o n ) .

T h e manua l control ler is not provided with a scale for sett ing cabin rate or alti tude. It requires moni -tor ing the t r iple indica tor cabin ra te and cabin al t i tude indicat ions until the dcsircd rate and alti-tude are obtained.

Figure 12-5. Manual Controller

TRIPLE INDICATOR T h e tr iple indica tor (F igure 12-6) inc ludes the fo l lowing indicators:

• Cabin rate needle

• Cabin alt i tude needle

• Different ia l pressure needle

T h e t r i p l e i n d i c a t o r a l s o t r i g g e r s a c a b i n a l t i t u d e w a r n i n g .

M A N U A L

Figure 12-6. Triple Indicator

Cabin Rate Needle The cabin rate needle indicatcs the cabin rate of climb or descent on the left scale.

Cabin Altitude Needle T h e cabin al t i tude needle, marked ALT, indicates the cabin pressure al t i tude in thousands of feet on the right inner scale.

Differential Pressure Needle T h e different ial pressure needle, marked AP, indi-cates the pressure differential (delta P) between cabin pressure and outs ide air pressure in pounds per squarc inch on the right outcr scale.

Cabin Altitude Warning An al t imetr ic switch within the tr iple indica tor closes when the cabin al t i tude reaches approxi -mate ly 10,000 feet. It sends a signal to the aircraft w a r n i n g s y s t e m w h i c h t r i g g e r s t he f o l l o w -ing i n d i c a t i o n s :

• A 3 -ch ime aural alert sounds.

• The voice warn ing " C a b i n " is given.

• T h e r ed C A B I N A L T l i g h t o n t h e M A P i l l u m i n a t e s .

• T h e mas ter W A R N I N G lights f lash .

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E M B - 1 2 0 PILÜT TRAINING M A N U A L

A L T I T U D E (FT)

L A N D I N G G E A R S W I T C H I N - F L I G H T P O S I T I O N

O

- 1 0 0 -

- 2 0 0 -

- 3 0 0 -

F U L L T H R O T T L E

T I M E

D E L A Y ( 1 5 S E C O N D S )

Figure 12-7. Automatic Pressurization during Takeoff

OPERATION Thc pressurization sys tem maintains the passenger cabin and cockpi t pressure by control l ing air-con-di t ioning out f low to the a tmosphere .

AUTOMATIC MODE T h e electronic control ler is powered by DC bus 2 when the m o d e selector is posi t ioned to A U T O .

On the ground, the control ler keeps both out f low valves open (cabin depressurized). The cabin is pres-surizcd automatically during takeoff and depressurized af ter landing.

Takeoff During takeoff with both air-conditioning packs oper-ational, the pressurizat ion control panei should be set up as fol lows:

• M o d e selector s w i t c h — A U T O

• Manua l control ler s e l e c t o r — D N

• R A T E knob—de ten t

• B A R O k n o b — C u r r e n t al t imeter

• ALT k n o b — A s s i g n e d cruise alt i tude

As the power levers are advanced for takeoff , a microswitch in the left control stand sends a signal to the electronic controller. The controller initiates cabin prepressurization at a descent rate of 450 f p m (Figure 12-7). This is done to avoid the sudden cabin pressurizat ion, or "bump," that wou ld occur if the out f low valves rapidly closed at rotation.

W h e n the a i rplane rotates, the landing gear p rox-imity UP switch sends a signal to the electronic con-troller to initiate a cabin climb of 650 fpm. The climb begins 15 seconds af ter rotation (Figure 12-7).

Climb and Cruise T h e electronic control ler senses cabin pressure as an input. During aireraft climb, it compares the rate of change of cabin pressure to the programmed cabin rate of c l imb (RATE knob) . The control ler ma in -t a i n s t he c a b i n c l i m b a t t h e p r o g r a m m e d r a t e

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ALTITUDE (FT)

- 1 0 0 - -

- 2 0 0 - -

CABIN ALTITUDE

LANDING G E A R S W I T C H INFLIGHT P O S I T I O N

O U T F L O W V A L V E S F U L L O P E N

/ 1 0

?í>0

20, 3 0 4 0 5 0 6 0 TIME ( S E C O N D S )

- 3 0 0

Figure 12-8. Automatic Depressurization after Touchdown

by m o d u l a t i n g the signal to the electropneumatic out f low valve torque motor.

Onee the cabin altitude set by the ALT knob is reached, it is mainta ined by the electronic controller.

With a cabin differential p ressure of 7 .0 ps id du r -ing cruise and the m a x i m u m differential pressure of 7 .2 psid, the a i reraf t m a y deviate up to 200 feet above the selected flight levei without causing a cabin bump.

Descent and Landing During dcsccnt, the ALT knob on the electronic con-troller should be set to 300 feet be low the landing lield elevation and the B A R O knob should be set to the current altimeter setting. Once set, the electronic controller mainta ins a cabin rate of descent of 450 f p m (Figure 12-8).

The electronic controller requires two signals to depres-surize the cabin af ter landing. T h e first is received f rom a microswitch in the left power lever quadrant w h e n the p o w e r levers a re r educed dur ing the

landing f lare. T h e second is f r o m the landing gear squat switches at touchdown. Once both signals are received, the control ler depressur izes the cabin at a rate of 6 5 0 f p m (Figure 12-8).

Once the cabin is depressurized (cabin altitude equal to outside altitude), the outflow valves are fully open.

MANUAL MODE The manual mode should be used only in the event o f a n e l e c t r i c a l p o w e r f a i l u r e o r a n A U T O m o d e f a i l u r e .

In M A N only, the pneumatie outflow valve operates.

T h e manua l m o d e is selected as fo l lows:

• Manua l control ler se lec tor—1 o ' c lock

• Wait 15 seconds

• M o d e s e l e c t o r — M A N

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E M B - 1 2 0 PILÜT T

T h e manua l control ler is used lo selecl lhe desired ra te of cab in c l imb or descen t . I t is sc lcc tab le be tween - 1 , 5 0 0 f p m (DN) and +2 ,500 f p m (UP).

Manua l mode operation requircs cont inuous mon-itoring of the triple indicator to keep the desired rate and maintain a comfor tab le cabin.

DEPRESSURIZATION

AUTO Mode In the automatic mode, the aireraft is depressurized by posit ioning the m o d e selector switch to DUMP. The cabin rate of climb is approximately 14,400 fpm.

At aireraft al t i tudes above 13,000 feet , cabin alti-tude is limited to 13,000 ±1,500 feet altitude by action of thc cabin altitude limiter on thc electropneumatic out f low valve.

MAN Mode In the manual mode, the aireraft is depressurized by the c lockwise actuation of the manual controller to the stop (UP). This opens the pneumatie outflow valve only and depressurizes the cabin at a rate of 2 ,500 f p m .

T h e r e i s no cab in a l t i tude l imi te r ins ta l led on the pneumat ie outf low valve. There fore , when the

M A N U A L

ai reraf t is depressur ized in the manua l m o d e , the cab in a l t i tude wil l c l imb unt i l i t equa l i ze s wi th a i re ra f t a l t i tude.

SAFETY DEVICES F o l l o w i n g is a s u m m a r y of the p re s su r i za t i on sys tem safe ty dev ices ins ta l led on the e l ec t ro -pneumat i c and pneumat i e out f low valves. Protec-t ions are ove rp re s su re re l ief , nega t ive -p ressure rel ief , and cabin al t i tude l imitat ion.

An overpressurization relief valve is installed on each outflow valve. When the valve senses thc cabin max-i m u m d i f fe ren t i a l p re s su re of 7 .2 ±0 .1 psid, i t opens and c l imbs (depressur izes) the cabin.

A negative-pressure relief valve is also installed on each outflow valve. Consisting primarily of a check valve, the valve o p e n s w h e n i t s enses a cabin negative differential pressure o f - 0 . 3 psid.

T h e cabin al t i tude l imiter is instal led on the e lec-t ropneumat ic out f low valve only. I t actuates w h e n it senses a cabin altitude of 13,000 ±1,500 feet. When the cabin al t i tude l imiter actuates , i t c loses the e lec t ropneumat ic ou t f low valve and, th rough the pneumat ie line connect ion, the pneumat ie outf low valve also.

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M O D E S E L E C T O R S W I T C H A U T O — S e l e c t s t h e m o d e o f o p e r a t i o n . E l e c t r o n i c c o n t r o l l e r o p e r a t e s t h e e l e c t r o p n e u m a t i c o u t f l o w v a l v e w h i c h , i n t u r n , d r i v e s t h e s l a v e d p n e u m a t i e o u t f l o w v a l v e ( n o r m a l o p e r a t i n g m o d e ) . M A N — S e l e c t s t h e m a n u a l m o d e o f o p e r a t i o n . M a n u a l c o n t r o l l e r p r o v i d e s i n p u t s t o t h e p n e u m a t i e o u t f l o w v a l v e o n l y . D U M P — ( S a f e t y g u a r d m u s t b e l i f t e d . ) R a p i d l y d e p r e s s u r i z e s t h e a i r e r a f t b y o p e n i n g b o t h a p p r o x i m a t e l y 1 4 , 4 0 0 f p m . A l t i t u d e l i m i t e r l imi t s c a b i n a l t i t u d e t o a p p r o x i m a t e l y 1 3 , 0 0 0 f t .

C A B I N C L I M B N E E D L E — I n d i c a t e s c a b i n r a t e o f c l i m b o r d e s c e n t . I n d e p e n d e n t o f m o d e o p e r a t i o n .

M A N U A L C O N T R O L L E R — P n e u m a t i c a l l y c o n t r o l s p n e u m a t i e o u t f l o w v a l v e i n M A N m o d e .

D N : C a b i n r a t e o f - 1 , 5 0 0 f p m U P : C a b i n r a t e o f + 2 , 5 0 0 f p m

B A R O S E T S C A L E — I n d i c a t e s t h e b a r o m e t r i c s e t t i n g .

A L T K N O B — R o t a t e s n e e d l e t o s e l e c t a l t i t u d e b e t w e e n - 1 , 5 0 0 f t a n d + 1 0 , 0 0 0 f t ( o u t e r s c a l e ) , o r a i r e r a f t f l i g h t a l t i t u d e ( i n n e r s c a l e ) .

C A B I N A L T I T U D E N E E D L E — I n d i c a t e s c a b i n p r e s s u r e a l t i t u d e o n t h e i n n e r s c a l e . I n d e p e n d e n t o f m o d e o p e r a t i o n .

C A B I N À P N E E D L E — I n d i c a t e s p r e s s u r e d i f f e r e n t i a l b e t w e e n c a b i n p r e s s u r e a n d o u t s i d e a i r p r e s s u r e o n t h e o u t e r s c a l e . I n d e p e n d e n t o f m o d e o p e r a t i o n .

R A T E K N O B — M a r k e d d e t e n t p o s i t i o n : S e l e c t s 6 5 0 f p m c a b i n c l i m b o r 4 5 0 f p m c a b i n d e s c e n t .

Ful l C C W : - 1 5 0 f p m c a b i n d e s c e n t o r + 2 0 0 f p m c a b i n c l i m b

Ful l C W : - 1 , 0 0 0 f p m c a b i n d e s c e n t o r + 1 , 4 5 0 f p m c a b i n c l i m b

B A R O K N O B — S e t s b a r o m e t r i c p r e s s u r e o n t h e B A R O S E T s c a l e b e t w e e n 2 9 . 0 0 a n d 3 1 . 0 0 i n H g .

E L E C T R O N I C C O N T R O L L E R N E E D L E — I n d i c a t e s t h e s e l e c t e d c a b i n a l t i t u d e o n o u t e r s c a l e , o r s e l e c t e d f l i gh t a l t i t u d e o n t h e i n n e r s c a l e .

Figure 12-9. Pressurization System Controls and Indicators

Rev is ion 4 FOR TRAINING PURPOSES ONLY 12-11

FlightSafety I n t e r n a t i o n a l '

E M B - 1 2 0 PILOT TRAINING M A N U A L

QUESTIONS 1. T h c ai rplanc is pressur izcd by mcans of:

A. R a m air en le r ing the cabin f rom wing scoops

B . C o n d i l i o n e d air f r o m a i r - cond i t ion ing sys tem

C. Pressurizat ion air p u m p D. Gasper fan outlets

2. Pressur izat ion is controlled in:

A. Sequcnce m o d e B. Automat ic m o d e C. Manual m o d e D. Both B and C

3. W h i c h of the fo l lowing is not pressur ized?

A. Flight deck B. Cabin C. Baggage compar tmen t D. Avionics compar tment

4. T h e m a x i m u m pressurizat ion differential is:

A. 6.5 psid B. 7.0 psid C. 7.2 psid D. 8.0 psid

5 . H o w m a n y o u t f l o w v a l v e s c o n t r o l a i r d i s c h a r g e ?

A. One B. Two C. Three D. Four

6 . I n t h e A U T O m o d e , w h i c h v a l v e s a r e o p e r a t i o n a l ?

A. Elec t ropneumat ic out f low valve B. Pneumat i e out f low valve C. Both A and B D. Ei ther A or B, depend ing on alt i tude

7. In manual mode, which valvc(s) are operational?

A. Elec t ropneumat ic out f low valve B. Pneumat i e out f low valve C. Both A and B D. Ei ther A or B, depending on alt i tude

8. T h e C A B I N warning light comes on at:

A. 9 ,000 f t B. 10,000 ft C. 12,000 ft D. 12,500 ft

9. Wi th the engines and electrical sys tem off:

A. Thc electropneumatic valve is closcd and the pneumat ie valve is open.

B. The electropneumatic valve is open and the pneumat ie valve is closed.

C. Both valves are open. D. Both valves are closed.

10. T h e absolute cabin al t i tude limit is:

A. 11,500 ft B. 13,000 ft C. 14,500 ft D. 15,000 ft

11. T h e cabin c l imb rate may be set be tween:

A . 5 0 - 1 , 0 0 0 f p m B. 100-1 ,000 f p m C . 2 0 0 - 1 , 4 5 0 f p m D. 2 0 0 - 1 , 5 0 0 f p m

12. T h e cabin descent rate may be set be tween:

A . 5 0 - 1 , 0 0 0 f p m B. 100-1 ,000 f p m C . 150 -1 ,000 f p m D. 150—1,450 f p m

12-12 FOR TRAINING PURPOSES ONLY Rev is ion 4

FlightSafety I n t e r n a t i o n a l *

E M B - 1 2 0 PILÜT TRAINING M A N U A L

13. On the g round , engines runn ing , electrical power on , power lcvcrs a t G N D I D L E :

A. T h e e lec t ropneumat ic valve is open. B. T h e pneumat ie valve is open. C. Both valves are closed. D. Both valves are open.

15. D u r i n g descen t , i f the con t ro l l e r is set as r c commendcd , the cabin should dcsccnd at:

A. 250 f p m B. 400 f p m C. 450 f p m D. 500 f p m

14. The A U T O mode of setting the pressurization is a lways used unless:

A. T h e f l ight is to be m a d e below 5 ,000 ft. B. There is an electrical failure. C . T h e A U T O system fails . D. Ei ther B or C is correct.

16. U p o n l and ing , t he cab in i s a u t o m a t i c a l l y depressur ized.

A. True B. False

FOR TRAINING PURPOSES ONLY 12-13