"DC" System
    Vast, but Reliable.  A good way to describe the Jetstar electrical system.  Now I will start using complete sentences.  The DC system on the Jetstar has a Main bus, an Essential bus, a Start bus, and an ignition bus.       With battery power only the Essential bus is powered.  Some aircraft are equipped with a "Ground Bus Tie" switch.  This allows the entire airplane to be powered by the batteries on the ground.  Use this for short periods of time only, or you will discharge the batteries in minutes.
    In normal operations, the APU is started to provide electrical and air.  The battery is then turned off prior to starting the first engine.  In this situation, the APU powers the electrical system, and the batteries connect themselves in series to start the first two engines.  The two generators are put on line, the battery switch is turned on, and the remaining engines are started.
    Generators connect to the Main Bus, and the main bus powers the Essential bus which charges the batteries.  If Main bus power is lost, the main bus is load shed, and the Essential Bus reverts to battery power.  Then, one of the generators may selected and placed in the emergency mode, powering the Essential Buss through the Start Bus.  Sounds complicated, but it's not.  Things have to get pretty bad in order to be without electrical power in this airplane.
"AC" System
    The AC requirements on the Jetstar are met with 3 inverters.  The # 1 inverter powers the Main and Essential AC busses.  The Windshield inverter provides power for windshield heat.  The # 2 inverter is a standby unit that can do the job of either of the other inverters.
    If one of the 3 inverters fails, the entire system can be operated with any of the remaining two inverters.  If two of the three inverters fail, you have some choices to make.  You can power the Capt.'s. instruments and heat the left forward windshield,  or power both sets of pilot instruments and have no window heat.  You are then limited to 225 kts below 10,000 msl.  This is true unless the only operating inverter is the" Windshield" inverter.  In that case, you can get the Capt.'s. instruments and his / her window heated, or normal window heat and no attitude and heading information for the pilots.  The # 2 inverter, and the transfer circuits are powered by the Essential DC Bus.
 

    The Jetstar is equipped with one of  two types of APU's, Airesearch, or Solar.  These small gas turbine engines, located in the tailcone, provide electrical power, and bleed air.  Both are limited to ground use only.  The APU must be off, and the APU door closed prior to starting the takeoff roll, and may be started on the landing roll below 140 kts.  The 140 kt limit protects the APU exhaust door.  The APU generator is rated at 300 amps, and has a current limiter between it and the Main DC bus that will blow if 325 amps is exceeded for more than a moment.  These current limiters cost $ 12.50 if you need to replace one.  If you have the APU generator online, and the battery switch ON, and try to start an engine, you will get an update on current limiter prices
    The APU air switch has three positions.  Main, which provides air to the air-conditioning units, Alternate which provides air to the cabin, bypassing the air-conditioning units, and off, which provides nothing.  You will use the APU almost always when on the ground, as the engines don't do a very good job of providing bleed air on the ground.

Ground Power
    Two ground power receptacles are found on the Jetstar.  They are located inside the ground power access door on the right side of the forward fuselage.  The oval shaped one allows the GPU to power the aircraft's main and essential busses, much the same as a ships generator would.  The rectangular one connects the GPU directly to the start bus.  If the rectangular plug is used, the engines start from GPU power only.  If the oval plug is used, the GPU powers the airplane systems, and the batteries start the engines by themselves.
 

Ailerons
    Roll control is achieved with boosted ailerons.  An electric trim tab is located on the left aileron, and a ground adjustable tab is on the right aileron.  Ailerons are powered by both hydraulic systems, or may be operated manually.
Elevator
    Pitch control is via an elevator, and a trimable horizontal stabilizer.  The elevator is boosted by both hydraulic systems, and may also be operated manually.  The horizontal stabilizer is used for pitch trim.  There are two pitch trim motors.  The normal trim is powered by the Main DC bus, and the emergency trim by the Essential DC bus.  A trim cutout button is provided to stop all trim on the airplane.  It can be reset after the offending system has been isolated.
Mach Trim
     A mach trim system is installed on all Jetstars.  This system compensates for the aircraft's tendency to pitch slightly nose down as the mach number increases, due to a shift in the center of pressure on the wing. (Initial formation of shock wave as you approach "Transonic" speed range.  Without the mach trim system operating, you are limited to 0.76 mach in the -6 & -8, and 0.72 mach in the 731 powered airplanes.
 

CAUTION

    When you run the mach trim test on the ground, make sure the system performs the entire test before you turn it off.  This is because if the test is not completed when the system is turned off, it will finish the test the next time it is turned on, like just after takeoff.  This is a major problem, unless of course, you want to die.  All kidding aside, this mistake can kill you if you make it, so don't.

Rudder
    The  rudder is equipped with a yaw damper, and on the 731 powered airplanes, a "Rudder Bias" system.  The Rudder Bias uses HP bleed air to actuate pneumatic servos that deflect the rudder toward the side of the airplane that is producing the most thrust in the event of engine failure or asymmetric thrust.  Rudder trim is via a moveable tab on the rudder itself.  The rudder trim tab is DC electric.
Speedbrake
    Do not use the speedbrake on the ground, unless you don't mind some of it being gone by the time you stop the airplane.  It is electrically controlled, and hydraulically actuated via the main hydraulic system.  You will get a flashing red warning if you have the speedbrake and the landing gear extended at the same time.
 

Engine Limitations
Jetstar - 6  & - 8

    The Jetstar fuel system consists of six fuel tanks, four internal, and two external.  The internal "Wing" tanks are located in the inboard and outboard section of each wing.  The outboard wing tanks hold 375 gal and the inboard wing tanks hold 390 gal each.  The engines are numbered 1 thru 4 starting from the left, and they feed form their respective wing tanks in the same manner.  Each internal tank has it's own electric fuel boost pump.  The "External" tanks are attached to the wings but extend a bit forward of the leading edge of the wing.  They each hold 565 gal on -6 and -8 airplanes, and 601 gal on the 731 and Jetstar II.  The external tanks each have an electric fuel boost pump.  On the 731 powered airplanes they have two pumps in each external tank.  If there is any fuel in the external tanks, the pumps must be turned on for 10 minutes prior to takeoff to properly distribute the fuel inside the tank.  Max external fuel for landing is 2,250 lbs per tank.  The external tanks on the 731 powered airplanes are mounted a bit lower as compared to the earlier models.  This was done to correct an airflow problem that caused problems with the outboard engines.
    The fuel system is designed such that any tank may feed any engine, or all the engines if need be.  The fuel pumps in the external tanks are of somewhat higher pressure, so to use the external fuel, after takeoff, make sure all the fuel pump switches are on, and open the crossfeed valves.  When the external fuel is consumed, turn off the pumps in those tanks and close the crossfeed valves.
    A separation valve is installed between the left and right sides of the fuel system.  This allows the left engines to feed from the right tanks, or the other way around.  Tanks 1 & 2 have an interconnect, as do tanks 3 & 4.  This allows gravity transfer between those tanks, but the tank receiving the fuel must be down to about 300 lbs fuel remaining.  Again, sounds complicated but it's not once you look at it in the airplane.
 

    The Jetstar has two hydraulic systems, a main and a standby.  The main system has an engine driven hydraulic pump on the # 2 engine, and an electric hydraulic, or "AUX" pump.  The engine driven pump provides pressure whenever the engine is turning, and the AUX pump provides pressure during Gear Retraction, Flap Extension, and whenever you turn it on with the switch.  The standby hydraulic system is powered by an engine driven hydraulic pump on the # 3 engine.  As you can see from the chart below, the flight controls are powered by both systems.  They can also be operated unboosted.  This is like driving a Cadillac through a slalom course without power steering, but it will allow you to land the airplane safely.
    Note:  To get the standby Nosewheel Steering, Flaps and Brakes, you must throw a guarded switch on the left side of the copilots forward panel.  Alternate brakes have no anti-skid protection.
 

    The main system can operate with the  # 2 engine driven hydraulic pump, or the "AUX" electric hydraulic pump.  If for any reason, the main system is inop, you have the following ways to deal with this tragedy:
 

    The pressurization on the Jetstar is regulated pneumatically, using the same system as most other aircraft of that era.  It is a good reliable system.  Cabin pressure can be dumped, or bled off through the use of a needle valve if the main controller fails.  Not much to go wrong here.
    All series of Jetstars have two refrigeration units, that take bleed air from the engines, cool it, and send it to the cabin and cockpit.  You have four bleed switches, one per engine.  Normal operation is with all 4 switches on, however for long range cruise, one may be turned off as long as cabin pressure can be maintained.  If the normal systems fail, the aircraft can be pressurized by the emergency system.  This system takes bleed air (LP on the 731), and pumps it through a heat exchanger and into the cabin.  Temperature control is achieved by a moveable door that regulates the amount of ambient air that is allowed to flow through and cool this little radiator.  This system is rarely used, but works great when you need it.  Most other aircraft are miserably hot when using emergency pressurization.  The Jetstar is much better than the rest of the pack here.
    On the 731 powered airplanes, designers of the bleed air system were born while their mothers standing up.  Why would I say such a thing?  Because the 731 has two bleed sources, LP, an HP.  Just about all other users of the 731 engine use a bleed valve that takes both air sources and gives you whatever air you need.  Great!  Not the Jetstar.  You are stuck with LP bleed, and you must leave one engine up at around 85% N1 on descent, if you have the unreasonable expectation that the airplane should remain pressurized on descent.  This is, however one of the few things about this airplane that is a pain in the ass.  Other than this, it's a pleasure to fly.
 

    The anti-ice systems on the Jetstar consist of DC powered Pitot / Static and AOA probe heat, AC powered windshield heat, and bleed air for the engines and nacelles.  The wings and tail are de-iced with inflatable boots.
    All of the systems except the engines and nacelles require electrical power to function.  The engines and nacelles anti-ice system fails ON in the event Essential DC electrical power is lost.  The electric power to control the de-ice boots comes from the "Main" DC bus.
 

    Here are some basic flight profiles that I have used over the years.  They are not the only way to fly the airplane, but have worked for me since I started giving training and checkrides in biz jets  little over 20 years ago.  In the event of a difference between this and the Aircraft Flight Manual, the flight manual is the document to follow.

Steep Turns

1.  Enter at 250 KTS indicated AIRSPEED.
2.  Bank aircraft 45 deg.  As you pass 30 deg of bank, pitch up 2 deg.  Add power to maintain AIRSPEED.
3.  Lead roll out by 15 deg.  Passing 30 deg bank, pitch down 2 deg  to maintain  altitude.
4.  Maintain 250 KTS and assigned heading.

Stall - Cruise Configuration

1.    Compute Vref & set AIRSPEED bugs.
2.    Maintain assigned altitude and set power to 50% N1.
3.    Trim for level flight until passing 160 KTS.  Maintain altitude with necessary back pressure.
4.    At first indication of a stall,  throttles to " MAX POWER "
5.    Call " MAX  POWER Flaps Approach.
6     Reduce pitch ONLY to the extent necessary to eliminate symptoms of the stall.
7.    Reestablish assigned altitude.
8.    At Vref + 30 KTS, call " Flaps Up, After Takeoff Checklist.  "
9.    Maintain AIRSPEED and altitude as directed.

Stall - Takeoff Configuration

1.  Compute Vref, set AIRSPEED bugs & select flaps approach.
2.  Maintain assigned altitude and set power to 50% N1.
3.  Trim for level flight until passing 160 KTS.
4.  Establish 25 deg bank angle and maintain altitude with necessary back pressure.
5.  At first indication of a stall, advance throttles & call " MAX POWER ".
6.  Level wings and reduce pitch ONLY to the extent necessary to eliminate symptoms of the stall.
7.  Reestablish assigned altitude.
8.  At Vref + 30 KTS, call " Flaps Up, After Takeoff Checklist.  "
9.  Maintain AIRSPEED and altitude as directed.

Stall - Landing Configuration

1.    Slow to flap speed, set 60% N1 & Set bug to Vref.
2.    Maintain assigned heading & altitude.
3.    Below 200 KTS, " Flaps Approach".
5.    Below 180 KTS, " Gear Down Landing Check ".
6.    Below 180 KTS, " Full flaps. " trim to Vref. Establish a 400-700 feet/min sink rate at Vref.
7.    Level off at designated altitude  W I T H O U T increase in power
8.    Maintain altitude until  first indication of a stall.
9.    Apply MAX power lower nose only as much as required to eliminate the stall.
       At Vref minus 10 KTS   M I N I M U M  speed, call for " Flaps Approach", and increase the
       pitch attitude to 10 deg nose up at about 1 deg / sec.
10.  When VSI & Altimeter indicate positive rate of climb call " Positive rate, Gear Up ".
11.  Establish 7.5 deg nose up attitude.
12.  At Vref + 30 KTS, Call " Flaps Up, After Takeoff Checklist ".
13.  Return to entry heading and altitude or as directed.

ILS Approach - Normal & One Engine Inop

1.    Intercept LOC at 140-160 KTS and Flaps Approach.
2.    One dot prior to intercepting Glide Slope, call " Gear Down Landing Check ".
3.    When ON the glidepath, call " Full Flaps ".
4.    Establish Vref to Vref + 5 KTS & track LOC & GS until Minimums.

ILS Approach - Two Engines Inop

 1.  Intercept LOC at 160 KTS and Flaps Approach.
 2.  Intercepting Glide Slope, call " Gear Down Landing Check ".
 3.  Establish Vref  + 25 KTS & track LOC & GS
 4.  At 100 Ft AGL, Full flaps, power idle & land.

Non Precision Approach

1.    Intercept Final Approach Course at 150 KTS and Flaps Approach.
2.    Crossing Final Approach Fix, call " Gear Down Landing Check ".
3.    Descend to and maintain MDA until Field in Sight or MAP is initiated. ( As Appropriate ).
4.    If Landing is to be made, call " Full Flaps " when intercepting a glidepath appropriate for a
       normal landing.  For one engine INOP, Vref + 5 KTS until 100 feet AGL, then " Full
       Flaps" so as to descend thru 50 ft AGL at Vref as in a normal landing.

No Flap Approach

1.  Vref + 40 KTS until established on Final Approach.
2.  Vref + 30 KTS on final.
3.  Approach angle NORMAL.  A flat approach will usually result in a longer landing roll.

Go Around or Missed Approach

1.  "Max Power", Rotate to 10 deg nose up, " Flaps Approach"
2.  Positive Rate of Climb, " Gear Up ", Vref + 30, " Flaps up, After Takeoff Checklist ".
3.  Climb at 200 KTS.
4.  Engine Failure or Fire Checklist if Appropriate.

Takeoff

1.  Set V2 on Capt. Airspeed & V1 on Co-Pilots Airspeed.
2.  At 80 kts, left hand moves from tiller to Yoke.
3.  At V1, right hand moves from throttles to Yoke.
4.  Vr, Rotate to 15 deg
5.  Climb at 15 deg pitch, or at V2 if engine failure
6.  At 400 ft & V2+30 KTS, "Flaps Up After T.O. Check ".
7.  Engine Failure or Fire Checklist if Appropriate.
8.  Climb  200 KTS to 3000 AGL then 250 Kts.

Rejected Takeoff

1.  Proceed as in normal takeoff until malfunction dictates that the takeoff be rejected.
2.  Capt. calls "Abort" (Co-Pilot may call Abort if Capt elects to delegate that authority).
3.  Thrust levers to idle
4.  Wheel brakes as necessary.
5.  Thrust Reverse deploy.
6.  If another takeoff is contemplated consider brake energy & appropriate turnaround time.

Emergency Descent

 1.    Oxygen masks on within 5 sec of cabin pressure loss.
 2.    Check passenger oxygen masks deployed.
 3.     Select Oxygen mask microphone.
 4.    Ignition ON.
 5.    Thrust levers to idle.
 6.    Speedbrake Extend.
 7.    Auto Pilot OFF.
 8.    Initiate 45 deg bank if desired.
 9.    Vmo/Mmo minus 10 kts to 14,000 or MEA as required.
10.  Clean up & proceed to nearest suitable airport if appropriate.

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