Don Johnson Aviation
WESTWIND 1 (1124) Study Guide
Limitations
Weights
Max Ramp Taxi Weight
23,000 lbs
Max Takeoff Weight
22,850 lbs
Max Landing Weight
19,000 lbs
Max Zero Fuel Weight
16,500 lbs
Speeds
Vmo / Mmo
Auto Pilot Disengaged
Vfe
12 Deg
20 Deg
40 Deg
Vle / Vlo
Alternate Extension
Vsb
250 kts
250 kts
180 kts
180 kts
140 kts
Vmo / Mmo
Max Tire Groundspeed
Va
20,700
19,000
17,500
15,000
13,500
DV Window Open
DJIC, INC.
360 kts / 0.765 Mach
/ 0.710 Mach
174 kts
230 kts
217 kts
204 kts
182 kts
170 kts
250 kts
Page 1
Operational Limits
Max Alt T.O. & LDG
10,000 ft
Max Enroute Altitude
45,000 ft
Max Alt. Flaps Extended
20,000 ft
Min Temp T.O. & LDG
-40 Deg C
Max Temperature
Min Temperature
ISA + 35 C
-54 C
Max Tailwind T.O/ LDG
10 kts
Max Runway Slope
2%
Max Fuel Imbalance
Enroute
Takeoff / Landing
800 lbs
300 lbs
Load Factor Limit
Flaps Up
Flaps Extended
+ 2.8 / -1.0 G
+ 2.0 /- 0.0 G
Avgas / Max Altitude
18,000 MSL
Max Alt / AP & YD Inop
Flaps 20 or More
10,000 MSL
Vmc & Crosswind
CROSSWIND (DEMONSTRATED)
VMCG
FLAPS 12 AND 20
VMCA
FLAPS 12 AND 20
DJIC, INC.
20 KTS
88 KTS
104 KTS
Page 2
Engine Limitations
Garrett TFE 731-3B
N2
ITT Deg C
Time
---
---
907 C
917 C
Abv 927
C
No Limit
10 Sec
Hot
Section
Takeoff
100.0%
101.0%
907 C
5 Minutes
Max
Continuous
100.0%
100.0%
885 C
30 Minutes
Max
Overspeed
101.5% to
103.0%
103.0% to
105.0%
103.0% to
105.0%
105.0%
------------
1 minute
5 Seconds
N1
Starting
START TIMES
10% N2 TO LIGHT-OFF
10 SEC
MAX
LIGHT-OFF TO IDLE
50 SEC
MAX
AIRSTART - FUEL FLOW
TO 60% N2
25 SEC
MAX
Engine Oil System Limitations
Max Oil Temp to 30,000 ft
above 30,000 ft
Transient ( 2 Min )
Max Oil Temp to open cap
Min Oil Temp for Start
Max oil consumption / 25 Hours
DJIC, INC.
127 C
140 C
149 C
30 C
-40 C
1 Quart
Page 3
STARTING / Lightoff --> Oil Press
10 Sec
IDLE
24 - 46 PSI
TAKEOFF, CLIMB CRUISE
38 - 46 PSI
Systems
Flight Controls
The ailerons and elevator and rudder on the Westwind are manually actuated by the pilots.
The aircraft does have an autopilot. The ailerons and elevator may be moved by the autopilot
servos, and the rudder is equipped with a yaw damper.
The flight controls on the Westwind Jet are operated by push / pull tubes and cables. They are
manually actuated by the pilot. They are servo controlled only when the auto pilot is in use. The
yaw damper system augments the displacement of the rudder, but may be easily overpowered by
the pilot. The trim systems, flaps, yaw damper and autopilot are electric.
Ailerons
The ailerons are located on the aft outboard section of each wing. Aileron trim is provided by a
DC electric motor that moves a tab located on the aileron itself. On the Westwind, as with most
airplanes equipped with a tiller for nosewheel steering, the co-pilot holds the aileron & elevator
controls on the takeoff until the rudder is effective enough for directional control on the ground.
This usually occurs between 80 and 100 knots. When this speed has been reached, the co-pilot
calls it out, and the captain responds, "I have the yoke".
Elevator
The Westwind is equipped with an elevator for pitch control, and a moveable horizontal
stabilizer for pitch trim. The elevator is moved manually by the pilot via push / pull tubes and
cables. When a pitch trim adjustment is desired, the horizontal stabilizer is moved by one of two
electric trim motors in the pitch trim system. The main pitch trim motor is activated by switches
on the pilot and co-pilot control yokes. If for any reason the main pitch trim does not function,
or runs without input from the crew, it may be disengaged by pressing the button on the inside
right portion of the captains control yoke. This not only turns off the main pitch trim, it makes
the alternate trim system available as well. This is indicated by the illumination of a red light on
the center pedestal. The toggle switch adjacent to the light now controls the pitch trim.
To test the pitch trim system, run the normal trim from each pilots yoke. When the trim is
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Page 4
running, depress the pitch trim cutout switch on the captains control wheel. This should
terminate any movement of the trim system. Now check the alternate pitch trim by moving the
alternate pitch trim switch. Press the red lighted button that is next to the alternate pitch trim
switch. This will restore normal pitch trim operation. Verify that the main pitch trim operates
again, and set it to the takeoff position. NEVER test any alternate or emergency trim system to
the limit of its travel. Alternate trim systems usually don't have electrical limit switches. The
system may jam, cost lots of money to fix, and the owner will be quite pissed off and you may
not be invited to fly that plane again.
Rudder
The rudder is actuated by tubes and cables via the rudder pedals on the cockpit floor. The
pedals are adjustable forward and aft with a hand crank on the lower forward panel in front of
each pilot. The yaw damper may be turned on after takeoff to enhance the yaw stability of the
aircraft. The yaw damper provides the most noticeable improvement in the ride when flying in
rough air.
Flaps
The flaps on the Westwind are operated by a 1.55 horsepower electric drive motor. The motor
is powered by the battery bus. The control circuit is on the # 1 DC Distribution Bus. Flaps may
be positioned UP, 12 deg, 20 deg at 250 Kts, and 40 deg at 180 Kts. The drive motor turns flex
cables that operate jackscrews, thus extending or retracting the flaps. A flap asymmetry
protection system compares the left and right flap positions. When a difference of 6.5 to 10
degrees exists, the flaps will stop moving. They are to be left in that position until repaired by
maintenance.
The flap asymmetry protection system may be checked by placing the flap unbalance switch
to the left or right position while the flaps are in motion. The flaps should stop until the switch is
released, then continue to the selected position. If the flap asymmetry system activates during
flap operation, return the flap selector to the last setting and land with whatever flap setting you
have. Add 15 knots to Vref for flaps up, 10 knots for flaps 10, and 5 knots for flaps 20 degrees.
Speedbrakes
The speedbrakes consist of single vented panels located on the top of each wing. They have the
vents in them to minimize buffeting. The speedbrakes are hydraulically actuated and electrically
controlled. There are no flight manual restrictions as to their use. They are deployed via a
switch in the cockpit. Speedbrakes on the Westwind are fully extended, or retracted. They
deploy when selected, and whenever the lift dump system is used.
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Lift Dump
The lift dump system consists of large inboard spoilers on the upper surface of the wing roots,
and the speedbrakes. In order for the lift dump system to deploy, both main gear squat switches
must indicate that the aircraft is on the ground, both throttles must be at idle, and lift dump must
be selected via the lift dump switch. Like the speedbrakes, the lift dump system is hydraulically
actuated and electrically controlled. Do not attempt to operate or even arm the lift dump system
in flight. Worst case, it will cause a crash, and in any case, the other pilot may want do
demonstrate the proper use of the crash ax on your head.
Landing Gear
The landing gear is hydraulically actuated and mechanically controlled. The only electrical
items related to the gear are the gear indication, warning, squat switch functions, and anti-skid.
With loss of electrical power, the gear may be extended normally, but will not retract because of
the down lock solenoid. If you are unfortunate enough to have a hydraulic failure, the gear may
free fall to the extended position if the fluid trapped in the uplocks leaks out. Prior to a long over
water flight, some operators check the uplocks by jacking the airplane, retracting the gear,
bleeding off the hydraulic pressure, and letting the aircraft sit for two or three hours to see if the
uplocks hold. Israeli Aircraft makes fine airplanes, however, there are a few things that indicate
some level of brain damage in one or more members of their design team. This is one of them.
The range and speed of the airplane is somewhat more limited with the gear down.
Brakes
The normal braking system requires main system hydraulic pressure. If electrical power is lost,
brakes will work, however, the anti-skid system will be inop, as it requires electrical power.
The emergency braking system uses an electric hydraulic pump to actuate the aft pads pucks
only. If the main hydraulic system fails, the emergency brake system will stop the airplane. The
emergency brakes need not be selected. When the main hydraulic system loses pressure, the
brake pedals will feel soft and will deflect to a much greater angle. Depressing the brake pedals
to this increased angle activates the emergency brakes. The emergency hydraulic pump is
activated whenever the gear is not on the uplocks. A pressure switch turns the pump on and off
to regulate the pressure from 750 to 1100 psi. Emergency brakes are not available without
electric power.
Thrust Reverse
The thrust reversers are electrically controlled and hydraulically actuated. They will not
function without electrical power. They are actuated by the main hydraulic system, or in the
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event that it fails, their own accumulator. If main hydraulic pressure is lost, and the hydraulic
low pressure light on the thrust reverser panel is not illuminated, the accumulator is charged and
you should get at least one cycle of thrust reverse. The reversers are locked in the stowed
position by a locking pin. When reverse is selected, the locking pin is retracted by the "BAS".
BAS stands for Big Ass Solenoid. The BAS is overriding a very powerful spring, and gets real
hot real quick. This is why reverse thrust is limited to 1 minute at a time.
Fuel System
Fuel Tanks
The fuel system on the Westwind Jet is fairly simple. Fuel is stored in the fuselage, wings, and
wing tip tanks. Fuel is pumped from the left and right fuselage tanks to their respective engines.
The fuselage tanks are connected by two interconnect manifolds and valves. The valves are DC
operated via a single rotating switch in the center of the lower overhead panel. When the valves
are open, fuel may flow freely between the left and right fuselage tanks. There is no way to
pump fuel from one side to the other. Gravity is the only help here.
The fuselage tanks are gravity fed from the wing tanks. The pilot has no control of this, as there
are no valves between the wings and fuselage. The wing tanks are replenished by the tip tanks.
First half of the tip tank fuel gravity feeds into the wings. The remaining fuel is pumped from
the tips to the wings via jet pumps. This fuel transfer may be selected by the crew, or set to
"Auto". In any case, if the transfer has not occurred by the time 6600 Lbs of fuel remain, place
the switch in transfer, and verify that the transfer is taking place. Landing with fuel in the tips is
prohibited.
FUEL CAPACITY
TANK
DJIC, INC.
US GAL
LBS
FUSELAGE
505.0
3,384
LEFT WING
282.5
1,893
RIGHT WING
282.5
1,893
LEFT TIP
115.0
770
Page 7
RIGHT TIP
TOTAL
AUX OPTIONAL
TOTAL
115.0
1,300.0
100.0
1,400.0
770
8,710
670
9,380
Fuel Pumps
The Westwind Jet has two electric boost pumps in each fuselage tank, a controllable jet pump in
each tip tank, and a jet pump in the lower forward section of each fuselage tank. Each engine is
equipped with a high pressure engine driven fuel pump. If this puppy does not work, find a hotel
because you're stuck!
Main Fuel Pumps
The main fuel pumps are 28 Volt DC Electric. The left main pump is powered by the #2 or
Right Main DC Bus, and the right main pump is powered by the #1 or Left Main DC Bus. They
should be operated from just prior to engine start, until the engine has spooled down to below
10% N2 RPM on shutdown. If the fuel pressure drops to below 7 PSI, indicating failure of the
main fuel boost pump, the alternate boost pump will come on. The alternate and main pumps are
powered from different electrical busses, so loss of one bus will not disable both boost pumps on
the same side.
Alternate pumps must be on before selecting main pumps. Selecting main pumps first will
result in the alternate pump turning on when the main is selected. The only way to get a main
pump on line without the alternate pump operating first is to pull the "Alternate Boost Pump"
circuit breaker. The pressure switch is then disabled because it is on the same circuit breaker as
the alternate pump itself.
Alternate Fuel Pumps
The alternate fuel pumps are also 28 Volt DC Electric. The left alternate pump is powered by
the #1 or Left Main DC Bus, and the right alternate pump is powered by the #2 or Right Main
DC Bus. They are selected just prior to engine start. The alternate boost pumps must be on prior
to selecting the main pumps, as the 7 PSI fuel pressure switches will turn on the "Alternate" if
the main pumps are selected first. When the main pumps are turned on when no pressure exists
in the fuel system, the pressure switches turn on the alternate pump prior to the main pumps
having enough time to build up the fuel pressure.
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Jet Pumps
The jet pumps get their power from the boost pumps. The jet pumps in the fuselage tank are for
the purpose of keeping the electric fuel pumps supplied with fuel during nose down attitudes
when the fuel level is low. These pumps are on whenever the boost pumps are operating. The
jet pumps in the tip tanks perform two functions. They transfer fuel form the wing tips into the
wings. They are also used to dump fuel if necessary.
Normal Operation
Prior to engine start, the fuel pump switches are set to "Main". This will cause the alternate
pumps to come on, as indicated by their amber annunciator lights. "Alternate" is then selected.
After the engines are started, the boost pumps are then selected to "Main". The switch must be
moved quickly from alternate to main through the off position, or the 7 PSI pressure switch will
put you right back into alternate. If this happens, you may say a bad word.
The "Fuel Transfer Switch" controls the transfer of the tip tank fuel into the wings. It should be
placed to Open, Closed, then to "Auto". This verifies the operation of the jet pump valves in the
fuel transfer system. This should cause the fuel to transfer from the tips to the wings at the
proper time. If the fuel transfer has not begun by the time the fuel quantity is down to 6600 Lbs,
the pilot should place the transfer switch to the open position. Once the transfer is complete, the
switch should be placed in the "Close" position.
Fuel Additive
There are no required fuel additives for the Westwind. The inside of the fuel system is coated
with a substance called Bunna N. It is non nutrient and does not allow the fungus to grow upon
it. The fuel icing issue is resolved through the use of fuel heaters. There operation is entirely
automatic. It is not required, but nonetheless a good idea to add Prist once every third or fourth
fueling to keep the water from accumulating in the fuel.
Refueling
There are two ways to refuel the Westwind. Single point refueling is the preferred method. If
this is not available, the aircraft may be fueled through two fuel caps located on the top of the
fuselage. Manual refueling valves are located between the wings and the wing tip tanks. These
valves are opened by pulling down on the metal rods protruding from under the wing, where it is
joined to the tip. When the valves are open, fuel may flow from the wing into the tip. When
the valve is closed (UP) the fuel may flow only from the tip to the wing. These valves must
always be closed prior to flight, otherwise a serious fuel imbalance may result. Maximum
pressure for single point refueling is 55 PSI.
Fuel Dump
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When it is necessary to dump fuel, verify that a fuel pump is operating on each side, then
depress the fuel dump switches on the overhead panel. This will open the fuel dump valves in
the bottom of the tip tanks. It also activates the tip tank jet pumps to boost the fuel dump. After
the tip tanks are empty, the motive flow fuel that was powering the jet pump is pumped
overboard through the fuel dump valve. If both the main and alternate pump on one side are
inop, open the interconnect valve to prevent a fuel imbalance. If no other pilot action is taken
and the system works properly, the dump should terminate at 950 pounds per side, or about 1900
lbs total.
If you are going to dump a bunch of fuel, do not do it in a holding pattern, as you may fly
back through the fuel vapor. This can cause you engines to do strange things, from overtemp to
a flameout. Notify ATC so another airplane does not fly through your vaporized fuel.
Hydraulic System
The Westwind Jet is equipped with a single hydraulic system. Skydrol is the type of fluid used.
Two engine driven hydraulic pumps power the system. An electric hydraulic pump is available
for emergency braking, and to set the parking brake. The pressure gauge for the emergency
system is direct reading, thus requires no electrical power. If you can remember only one thing
about this airplane, PARKING BRAKE DOES NOT HOLD IF ANTI-SKID SYSTEM IS
ON!
Hydraulic Systems
Main
Emergency
Nosewheel
Steering
Emergency
Brakes
Landing Gear
Parking Brake
Normal Braking
Speedbrakes
Thrust
Reversers
The main system can operate on one engine driven hydraulic pump. If for any reason, the
main system is inop, you have the following ways to deal with this tragedy:
System
Nosewheel Steering
DJIC, INC.
Alternate Procedure
Differential Brakes
Page 10
Landing Gear
Blow Down Bottle
Normal Brakes
Emergency Brakes
(No Anti-Skid)
Speedbrakes
Inop - Plan Ahead
Thrust Reversers
Accumulator
If the hydraulic pump on a failed engine is still good, a windmilling engine will provide some
hydraulic pressure. Motoring of a failed engine may provide some hydraulic pressure for normal
braking. If you have a main hydraulic system failure, don't be a hero. Stop the airplane, exit the
runway only if it is safe to do so, and call for a tow.
Normal Operation
Do not forget to bleed the thrust reverser accumulator pressure prior to checking the fluid
quantity. If you fail to bleed the accumulator, you will over fill the system, and get a reminder
that skydrol is an effective paint remover. If you are going to add fluid, bleed off the reservoir
head pressure so you don't get a face full of hydraulic fluid when you remove the cap
Turn the battery switch on, let the emergency hydraulic pump pressurize its system, and set the
parking brake. During the first engine start, rest your feet on the brake pedals and feel the main
hydraulic system pressure come up. Another way to determine that the hydraulic system
pressure is up is to watch the thrust reverser low pressure annunciator light. It will go out when
the main system charges the thrust reverser accumulator. Check the hydraulic pressure gauge.
It will indicate properly only when an inverter is on, because it is AC Powered. The pressure
gauge for the emergency hydraulic system is direct reading, and requires no electrical power
unless it is dark and you need a flashlight. A match may work in an emergency. Use the fire
extinguisher located in the cockpit if things get out of hand.
Nosewheel Steering
The nose wheel steering is controlled with a wheel type tiller located on the left side panel of the
cockpit. It will work any time there is hydraulic pressure in the main system and the nose gear is
down. You will find it fairly touchy to operate. Go easy at high speeds. On the preflight, you
did hook up the nose steering, didn't you? If not, the nose wheel may not come down when
requested, or it may come down with the wheels facing other than straight ahead. In this case,
you have a real problem. If there is any doubt, get out and check it before you inadvertently sign
up for a potentially wild and dangerous ride, and an interesting interlude with the Feds after your
release from the local emergency room!
During the takeoff roll, start using the rudder early. Use the nose steering to fulfill any
steering needs that the rudder won't handle. Doing this will really smooth out the ride. Ride
through one takeoff in the back of the airplane if you can. This will show you that the people in
the back don't get the sensation of radical movement that you experience in the cockpit when the
steering is in use. When you reach between 80 and 90 knots, the rudder should be sufficient. If
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this is so, the Captain places his (her if female, their if multiple personality or Siamese twins) left
hand on the control yoke. At V1, the right hand leaves the thrust levers and finds a new home on
the yoke as well. Do not play with the tiller in flight.
On the landing roll, the copilot takes the yoke at 80 to 90 knots. Roll corrections that were in
place are maintained or adjusted as appropriate. The Captain then rests his hand on the tiller, and
steers with the rudder until the rudder is no longer effective. Then the tiller is used for the
remainder of the landing roll and taxi.
Brakes
The brakes on the Westwind are hydraulic. Normal brakes use pressure from the main
hydraulic system. This pressure is used to operate forward and aft calipers for each wheel.
Brake pressure is modulated with the brake pedals. Anti skid protection is provided by an
electrical anti skid system. This system is good, but does not like to share the stage with the
parking brake. If the parking brake is set, and the anti skid is on, or is turned on, the brakes get
very unhappy and give up. Yes, the anti skid thinks the wheels are locked, because they are, and
releases brake pressure. This can be a real pain in the ass if you forget at the wrong time.
Landing Gear
The landing gear is hydraulic. What a surprise! It is powered by the main hydraulic system.
The normal extension and retraction of the gear is not dependent upon electrical power, as in
many aircraft. The gear handle on the Westwind actually moves a hydraulic valve that operates
the gear. Indication and anti-skid protection is all that is lost if an electrical failure occurs after
the gear is retracted. If you have an electrical failure prior to retracting the gear, the ground
safety solenoid will not let you move the gear handle out of the down position. It does take
electrical power to override this. The most likely use for the override would be the failure of a
squat switch followed by an engine failure after V1, but prior to gear retraction, as leaving the
gear down would result in a substantial loss of climb performance.
Alternate extension of the gear is done by placing the gear handle in the down position,
unlatching the emergency gear handle and rotating it 90 degrees aft, and pulling it up to
discharge the nitrogen into the down side of the forward main landing gear actuators. The nose
wheel is extended by a bunge.
If the main hydraulic system is not providing pressure to the brakes, the brake pedals can be
depressed farther by the pilot's feet. This activates the emergency braking system. The
emergency brake system takes fluid from a standpipe in the main hydraulic system reservoir. An
electric hydraulic pump supplies brake pressure to the aft brake calipers only. There is no anti
skid protection when using the emergency brake system. The emergency brake system is what
you use to set the parking brake prior to starting engines, as you most likely will not have main
system hydraulic pressure until one of your engines is started.
Speedbrakes
The speedbrakes and lift dump system are hydraulically powered and electrically controlled.
The speed brakes have no restrictions on their use. They may be extended with the speedbrake
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switch whenever you have electrical and hydraulic power available. The lift dump system
consists of the speedbrakes and another panel on the inboard section of each wing. The lift dump
system is allowed only on the ground during landing roll. In order to operate, both main gear
squat switches must be compressed, both thrust levers must be at idle, and the lift dump switch
must be placed in the lift dump position. The lift dump system deploys the speedbrakes and the
inboard lift dump panels.
Thrust Reverse
The thrust reversers are hydraulically actuated and electrically controlled. The must be armed
with switches beneath the thrust levers, and will then deploy when the reverse levers are moved
upward and back by the pilot. Limit the use of reverse thrust to one minute. This is because a
large solenoid must retract the thrust reverser locking pins. This solenoid draws lots of power
and will overheat if used for more than one minute at a time. You are limited to idle power in
thrust reverse below 70 knots. The thrust reversers require main system hydraulic pressure, and
electrical to operate. They have their own accumulator that will deploy them once after the
failure of the main hydraulic system.
HYDRAULIC SYSTEM LIMITATIONS
MAX PRESSURE
2,200
PSI
MIN PRESSURE
1,400
PSI
MAX EMERGENCY
PRESSURE
1,300
PSI
MIN EMERGENCY
PRESSURE
750
PSI
Electrical System
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Westwind Electrical System
The electrical system on the Westwind Jet consists of two batteries, two generators, and a system
of electrical busses. Engine starting may be performed using the aircraft batteries, or an external
power unit.
The starter generators on the Westwind are powered by 28 Volt DC when an external power
unit is used. During a battery start, the batteries are connected in series, providing 48 Volt DC
for engine start. When using an external power source, start one engine only, disconnect the
external source, and start the other engine with the aircraft batteries. During the second engine
start, the operating generator powers some of the aircraft's busses, but does not assist, or "cross
generator start" the other engine. The second engine is started with the batteries in series, the
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same as the first. It does not matter which engine you start first. The right engine is the norm, as
the entry door is on the left side.
The left and right main DC Busses are located in the fuselage aft of the passenger
compartment. Three feeder lines connect each main bus to its respective distribution bus in the
cockpit. These feeder lines have circuit breakers on each end. A remote 50 amp CB is located
adjacent to the main DC Bus, and a 35 amp CB is in the cockpit. A distribution bus tie breaker is
can connect the left and right distribution busses if all three feeder lines are disabled on one side.
This "Distribution Bus Tie" is normally pulled. It is "set", or pushed in only in the event one of
the main busses is not powering it's respective distribution bus.
The main busses power fuel boost pumps, inverters, windshield, and baggage heat. The
distribution busses power most of the other items on the aircraft. The flap motor is powered by
the battery bus, and flap control is on the #1 DC distribution bus.
The loss of one main bus will not result in the loss of both fuel boost pumps on one side. The
loss of one generator will cause the load shedding of the baggage heat, the respective windshield
heat, and the loss of some other minor items. The windshield heat may be reactivated by placing
the battery switch to the "Override Load Reduct" position. This works ONLY if both batteries
are connected. This would normally be the case unless one of the batteries overheated and was
disconnected by the crew.
The generator control units on the Westwind incorporate a feature that is common to many other
aircraft. The voltage is regulated to 27 Volts DC for the first 2 minutes after the first engine is
started. This is to reduce the likelihood of a battery overheat, as it reduces the initial charging
rate. After two minutes, the voltage returns to 28.5 Volts, which can be confirmed by the
increase in voltage, and the rise in amps on the generator load meter.
Voltage
28.5 Volt
Generators 300 Amps
Batteries
24 Volt / 23 Amp
Hour
Ice Protection
The Westwind is certified for flight into known or forecast icing conditions. The engines are
anti iced by bleed air. The bleed air heats the nacelle lip and stators. If the engines are equipped
with the old "Bullet Nose" spinners, they are also heated with bleed air. The P2/T2 probe is
heated electrically. The conical spinners do not require heat due to their shape. Turn on the
ignition prior to turning on engine anti ice, and leave it on until after the engine anti ice is turned
off. Do no operate the engine anti ice on the ground for more than 10 sec if the ambient
temperature is more than 40 deg F.
The pitot / static system is electrically heated. On the older airplanes you have an ON / OFF
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switch, and on the newer ones, a switch with OVERIDE, AUTO, and OFF. Override is "ON",
"AUTO" is on whenever the nosewheel strut is extended, and "OFF" is off.
The windshields are heated electrically. The High and Low settings are merely different
temperature settings for the thermostats that control the windshield temperature. With loss of
one generator, the respective windshield heat will be load shed, along with the baggage heat. As
long as both batteries are online, windshield heat may be restored by placing the battery switch
to the "Override Load Reduct" position.
The forward baggage compartment is electrically heated, unless the extended range fuel tank
is installed. It is controlled with a switch in the cockpit. The switch has three positions, OFF,
ON and Test. When you turn the baggage heat ON, the heating elements come on only if the
temperature is cold enough to require heat. If you do not see a rise in amps on the generator
when turning on the baggage heat, select "TEST", and you will see an increase in amps,
indicating operation of the heating elements. The "TEST" position overrides the thermostat and
powers the heating elements regardless of the temperature.
The wings and tail of the Westwind are equipped with De-Ice boots. When a quarter to a half
an inch of ice has formed, cycle the boots and remove it. Do not cycle the boots during takeoff
and landing, or when performing intentional stalls. Also, if you want to cycle the boots once in a
while to check them, do it when the wing and tail are nice and warm as it is easier on the boots
that way.
ENVIRONMENTAL
The Westwind is heated, cooled, and pressurized by engine bleed air. Bleed air is extracted
from both engines. LP and HP bleed air is supplied to the "Bleed Switching Valve" or BSV.
The BSV modulates or mixes the low and high pressure air in order to provide between 18.5 and
27 PSI bleed air to the environmental system.
The air travels through the "ACM" or air cycle machine. This consists of a heat exchanger, a
compressor, another heat exchanger, an expansion turbine. A temperature control valve may be
opened or closed to regulate the amount of air that goes through the ACM, and the amount that
goes around it. Since the bleed air is hot, and it was not cooled by going through the air cycle
machine, the cabin temp will increase. If for some reason the normal mode of heating & airconditioning is not available, emergency bleed air may be provided for pressurization from the
right engine's LP compressor section. This air will be hot; kind of like riding in a black station
wagon in the Arizona desert in the summer. It won't kill you but it ain’t much fun.
The cabin temperature control valve is positioned electrically. Both manual, and automatic
temp control require electrical power. Manual allows the "Cold / Hot" switch to move the valve
to the desired position. "Auto" on a Westwind positions the temperature control valve in
accordance with instructions from a thermostat. The auto system works about as well as Jane
Fonda as a goodwill ambassador to the VFW. I suggest you use manual temp control.
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The Westwind is equipped with an oxygen system. The oxygen valve must be turned on and
the system checked prior to flight. If the system pressure reaches zero, it must be inspected,
cleaned, and serviced by an appropriate repair facility.
GROUND PRESSURIZATION CONTROL
The "Ground Pressure Control switch causes the outflow valves to migrate slowly to the closed
position to smooth out the pressure spike that results when the bleed air switch is placed from
"Ram" to "Normal" after liftoff. You may elect to takeoff with the bleed air on if you are not
performance limited. Bleed air on has the same effect on the aircraft's performance as an
additional 300 Lbs of weight. If you make a bleeds off takeoff, and turn the bleeds on right after
liftoff, the transition usually not a problem.
Pay attention to this light if it illuminates other than during the test of the annunciator pannel.
This malfunction can hurt you if you don't deal with it properly.
BLEED AIR
LEAK
The Westwind has two bleed air leak lights. One for the left, and one for the right. These lights
tell you that hot bleed air is going somewhere that it does not belong. The first step to deal with
this light is to select "Emergency" with the bleed air selector switch. This closes both bleed
switching valves, and opens the emergency pressurization valve, supplying hot bleed air from the
right LP compressor section to pressurize the cabin. To regulate the temperature, adjust the
throttle as flight conditions permit.
If the bleed air leak light goes out, this tells you that you can control the problem with the
valves. The checklist will guide you through the process of selecting left an right bleed sources
to isolate the problem and possibly restore normal air conditioning with one bleed source.
If the bleed air leak light does not go out, you may have a leak that can't be controlled with
the valves. This could mean that the leak is between the engine and the bleed switching valve, or
that the bleed air valve will not close. In this case, you must retard the thrust levers one at a
time, and possibly shut down one of the engines. This could be a real bugger if you are
somewhere between the west coast and the Hawaiian Islands.
If it is necessary to operate the pressurization system in the emergency mode, you may get an
"Emergency Air Temp Hi" light. If this occurs, retard the right thrust lever to the extent
necessary to extinguish the light.
AIR CONDITIONING SMOKE
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If you should happen to experience air conditioning smoke, you should first don your oxygen
mask and smoke goggles, then, if necessary, raise the cabin altitude to the extent necessary for
visibility. Deploy the passenger oxygen masks if necessary. Now you may attempt to isolate the
source of the smoke as follows:
1) Bleed air switch to left engine:
Smoke stops, Leave in Left Engine.
Smoke continues, Perform step # 2
2) Bleed air switch to right engine:
Smoke stops, Leave in right Engine.
Smoke continues, Perform step # 3
3) Bleed air switch to Emergency:
Smoke stops, Leave in Emergency and Land.
Smoke continues, Depressurize cabin. When
cabin differential = 0, bleed air switch to "Ram".
The engines and the ACM are the most likely sources of air conditioning smoke, as they contain
oil. The above mentioned procedure should prevent any additional smoke from entering the
cabin.
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