Ramp 18,800   Some are 17,800
Takeoff 25 deg Flap 18,500    Some are 17,500
Takeoff  0 deg Flap 16,800
Landing 16,000
Zero Fuel 12,340
Max Fuel imbalance 1000 lb


Vmo/Mmo 360 kts / .765 Mach
Vfe 160 kts  (Same for App & Full)
Vsb 360 kts / .765 Mach
Vlo/Vle 180 kts
Max Tire Speed 174 kts
Landing Lights 180 kts
Windshield Wipers 180 kts
Max Altitude 41,000 FT  (45,000 Crew only OX mask on)
Tire Pressure  125 psi - Mains
  40 psi - Nose
Gear Bottle press 1800 psi
Accumulator Precharge 1100 psi

General Electric CJ-610-1 or CJ-610-5

Max N1 
716 C

Climb speed schedule:    200 kts to 2500 AGL  *

   * FAR *               250 kts to 10,000 MSL
  "Aircraft Speed"
   200 kts in Class D Airspace, 250 kts below 10,000 MSL
265 kts till reaching 0.65 Mach,  0.65 Mach to cruise altitude

         Note: If trying to climb above 35,000 when heavy
         0.67 mach may give better climb rate, and avoid possible
        flamout at high altitude and high angle of attack.



 The 1121 electrical system consists of a 28 Volt DC system, a variable frequency AC system, and a constant frequency 115 volt 400 cycle AC system.

DC system:

 The DC system consist of 2 x 24 Volt Batteries, two starter/generators, an external power receptacle,  and a system of DC busses.

Left Gen Bus
Right Gen Bus
Tie Buss
Pilots Essential
No 3# Buss

Bus Tie Switches

 The "Bus Tie Switches" have 3 positions, Off, Normal and Alternate.  Select off, and there will be NO tie between any of the busses, and no battery charging will occur.  Select Normal, and the batteries will charge if the generator(s) are on line.  The system will operate normally until the left or right generator drops off line.  In Normal, the loss of a generator results in the respective generator bus being unpowered.  This may be referred to as "Auto Load Shed".
 If "Alternate" is selected, the entire DC system operates in parallel, therefore the loss of a generator Will Not cause the loss of any electrical equipment unless both generators are lost and the batteries become discharged.   For normal operations, place the bus tie switches to alternate and leave them there.  The only time you need them in Normal is during a GPU start, or when you want automatic load shed to occur in the event of a generator malfunction.  One generator can handle the DC load alone, so auto load shed is not normally necessary.

The Following is a list of the items powered each DC Bus:

# 1 DC BUS

Aileron Trim Actuator 
Anti-Skid control 
 LH bleed air valve 
 Cabin lighting 
 LH Eng inlet anti-ice valve 
 LH Eng inlet warning light 
 Fuel quantity gauge 
 LH Gen bearing fail light 
 LH landing light & actuator 
 LH low oil press light 
 Rear compartment lights 
 LH windshield wiper 
 Pilots pitch trim control 
Aileron Trim Indicator
Auto/Man temp select relay
 LH bleed air low light
Cabin temp HI limiter (auto)
 LH Eng ice valve control
  Flap position indicator
 LH Fuel inlet temp
 Fuel interconnect lights
 Normal airframe de-ice
 LH oil temp gauge
Windshield temp control
 Position lights
 Pilots map light

# 2 DC BUS

Anti-collision light 
RH bleed air lo light 
Cabin altitude warn light 
Cabin lights & signs 
Co-Pilot pitch trim switch 
RH eng inlet anti-ice cont 
Fuel tank temp 
RH eng anti-ice control 
RH eng heat warning light 
Pitch trim indicator 
RH landing light 
RH lo oil press light 
RH windshield temp control 
Rudder trim actuator 
Anti-Skid off light
RH bleed valve
Cabin door unsafe light
Cabin temp HI limit (Man)
Co-Pilots map light
RH eng anti-ice valve
RH fuel inlet temp
RH eng anti-ice valve
RH gen bearing fail light
Alternate pitch trim
Rear comp unsafe light
RH oil temp gauge
RH windshield wiper
Rudder trim indicator

# 3 DC BUS

AC System control 
AC Meter switch 
Edge lights 
RH Fire detection 
Fire bottles 
RH fuel filter bypass light 
Low fuel light 
Aft fuel interconnect 
RH fuel tank shutoff valve 
Guide vane heat warn light 
Icing cond exist light 
Landing gear position lights 
RH oil press low light 
RH speed sensor 
AC Boost pump control
RH DC Boost pump (cont & pwr)
EMGY Hyd low press light
RH fire handle
RH F/W shutoff valves
RH fuel heat
RH fuel press low light
Aft fuel intransit light
RH fuel s/o intransit light
RH hyd s/o valve
RH Igniter
Landing gear warning horn
RH pilot static heat
RH turn and bank


LH AC control 
Annunciator panel test 
Bus tie switches 
Emgy air temp high light 
Emgy hydraulic pump 
LH fire s/o valve 
Fire test 
Flap control valve 
LH fuel filter bypass light 
LH fuel press low light 
FWD fuel interconnect 
Pitch trim override switch 
Landing gear override 
Nose gear steering 
Oxygen control 
Dome light & ram air valve 
Windshield heat warning 
LH AC boost pump control
Attitude gyro warning
DC Gen off lights
Emgy bleed valve
LH fire detection
LH fire handle
Fire bottles
Flap override switch
LH fuel heat
LH fuel s/o valve
FWD intransit light
DC Pitch trim motor
Mach warning
Override de-ice
Speedbrake control
Pitot static heat
Speed sensor & turn & bank

Variable Frequency AC

 The variable frequency or "Wild AC" system consist of two engine driven alternators which produce variable frequency AC power.  This "Wild AC" powers the following:

Left Var Freq AC BUS
Right Var Freq AC BUS
LH Main fuel boost pump  RH Main fuel boost pump
LH Windshield  RH Windshield heat
Main pitch trim motor RH constant freq converter
LH constant freq Converter

  Note: Some of the first aircraft had "Wild AC" engine inlet heat, however this system has been replaced with a system that heats the inlets with 8th stage engine bleed air.

Constant Frequency AC System:

   The constant frequency AC system consist of two constant frequency converters which take "Wild AC" and convert it to constant frequency 400 hz 115 Volt AC power to power the gyros, engine pressure instruments, main hydraulic system pressure gauge, fuel flow meters and counter, radar, and radio altimeter.  The 400 HZ 26 VAC power is obtained from transformers which get their power from the constant frequency busses.  In the event of the loss of one Constant Frequency Converter, leave the AC system switches in the "ON" position to preserve the automatic load transfer.  The main hydraulic pressure and engine pressure gauges do not operate until 400 hz AC power is available.  Remember the old rule
"AC lies and DC dies."  When they become unpowered, AC gauges stay at the value that existed when power was removed, and DC gauges die, or read zero.  The electrical busses listed below are all constant frequency 400 HZ (cycles per second) regulated AC power.

Left 115 VAC
Right 115 VAC
LH EPR gauge RH EPR gauge
LH ADI (Horizon) RH ADI (Horizon)
LH HSI (Directional gyro) RH HSI (Directional gyro)
Auto Pilot WX Radar
L & R Fuel flow & counter
Cabin temp control (Auto)
Water separator temp control
Ice detector power

Left 26 VAC 
Right 26 VAC
LH Fuel pressure gauge RH Fuel pressure gauge
LH Fuel pressure sensor RH Fuel pressure sender
LH Oil pressure gauge RH Oil pressure gauge
LH Oil pressure sensor RH Oil pressure sensor
Main Hydraulic press gauge


   The fuel system consists of wing tanks, and fuselage tanks, two AC, and two DC fuel pumps, and two  DC electric motor driven valves interconnecting the bladder type fuselage tanks.  The wing tanks are coated with a compound known as buna N.  It is a non nutrient surface that does not support the growth of fungus in the fuel system.  Fuel heat is provided by engine bleed air, thus, fuel additives are permissible, but not required.
   The fuel is added to the wing tanks, and gravity flows into the respective fuselage tank.  Jet pumps (driven by the main or alternate boost pumps) transfer fuel from the forward sump of the center tanks to the main sumps in the lower aft portion of the fuselage tanks.  This assures that the main sumps will remain full during nose low attitudes when fuel quantity is low.  The engines are started with the DC fuel pumps, then switched to the AC pumps for the remainder of the flight.  In the event the AC pump fails, the fuel pressure dropping to less than 7 PSI will cause the DC fuel boost pump to come on, keeping the fuel pressure within limits.
   The fuel boost pump check (after engine start, and when the AC system is powered) is as follows:
        1) Fuel pump OFF - Low fuel pressure light ON
        2) Fuel pump ON  - Low fuel pressure light OUT and DC boost pump ON
        3) Fuel pump mode switch to RESET - DC fuel boost
       light OUT, AC fuel pump maintaining fuel pressure within limits.
  A hard landing may cause the DC Fuel Boost pumps to come on, due   to a pressure surge in the system.  This does not damage the pumps    or the fuel system, but may have an adverse effect on the pilots ego.


 The 1121 hydraulic system consists of a 1.2 gal reservoir located just aft of the baggage compartment,  two engine driven hydraulic pumps, and one emergency electric hydraulic pump which operates only the emergency braking system.  The system uses Skydrol 500A hydraulic fluid and operates at about 1800 psi with relief at 2250 psi.
 The hydraulic system operates the Main Wheel Brakes, Landing Gear, Nosewheel Steering, Speedbrakes, Flaps, and the optional thrust reversers if installed.

Main Wheel Brakes

 The brakes are operated using pressure from the engine driven hydraulic pumps.  An Anti-Skid system provides skid protection for each main wheel when there is electrical power available and the system is turned on.  A hydraulic fuse located downstream of the power brake valve protects the main system from fluid loss in the event of a leak in the brakes.
Emergency Brakes

 The emergency braking systems electrically driven hydraulic pump supplies pressure for emergency braking and for setting the parking brake prior to engine start.  This pump cycles between 750 and 1000 PSI when the gear is not up and locked.  It operates only the aft set of brake calipers, and is less effective than the normal braking system.  One pint of hydraulic fluid in the main system reservoir is reserved for the emergency braking system via a stand pipe. Anti skid is not available when the emergency braking system is used.  The pilot need not do anything but depress the brake pedals to activate the emergency system.  Emergency braking is done using the same brake pedals as the main system.  When the main brakes are not able to function, the pedals will allow themselves to be pressed further down, thus engaging the emergency brakes.  Loss of DC electrical means loss of the Emergency Brakes!  If no braking occurs when the brake pedals are fully depressed, then no wheel brakes are available.  In that case, I hope your aircraft has thrust reverse, Drag Chute, or something soft and cheap to hit at the end of the runway.

 Nosewheel Steering

 Nose steering is hydraulically actuated, and is controlled with a tiller located on the left side of the cockpit.  A nose gear ground contact switch will open the steering bypass valve when the nose strut is fully extended, allowing a centering spring to center the nosewheel assembly, when the nose wheels are off the ground, or when there is no steering signal (Input from the pilot via the tiller,) being sent to the steering control valve.

Landing Gear

 To retract the landing gear, place the gear handle in the up position.  This releases the downlocks, and provides hydraulic pressure to the up side of the nose gear and main gear actuators.  A solenoid operated pin will lock the gear handle in the down position when the main gear struts are compressed.  In the event of squat switch failure, the solenoid can be overridden by the override button on the landing gear control panel.  This will allow the gear handle to be placed in the up position even if the aircraft "thinks"
it is on the ground.  Use with extreme caution, as this may cause severe humiliation and significant expense.
 Normal gear extension is performed by placing the gear handle to the down position.  This mechanically repositions the landing gear control valve, thus releasing the uplocks, and supplying hydraulic pressure to the nose gear actuator, and each aft main gear actuator.  Gear uplocks are released even if no system pressure exists as the pressure that keeps them engaged is ported to the return line.
 Emergency gear extension is achieved by placing the gear handle in the down position, then discharging the landing gear blowdown bottle (1800 psi nitrogen) into the forward main gear actuators with the emergency gear handle located on the left side of the throttle quadrant.  The nose gear is extended by spring bungees.  Loss of electrical power has no effect on landing gear operation, however, it does disable the landing gear indicating system.


 The wing flaps on the 1121 are of the split flap type. They are hydraulically actuated and electrically controlled.
A torque tube interconnects them to prevent an asymmetric flap condition.  The normal flap control, (# 2 DC Bus) allows flaps 0, Take-Off & Approach (25 deg) and Full.  Alternate flap control, (Pilots ESS DC Bus),  will allow the flaps to be placed in any desired position.   Loss of electrical power will result in loss of flap control.


 The 1121 speedbrakes are hydraulically actuated, and electrically controlled.  They have only positions, retract, and extend.  The speedbrakes will extend only partially at speeds in excess of 250 kts due to the high load imposed by the airflow.  There are no restrictions on use of speedbrakes with flaps on the 1121.  The loss of power to the Pilots Essential DC Bus will result in loss of the speedbrakes.

Thrust Reversers

 The optional thrust reversers are electrically controlled and hydraulically actuated.  They have their own accumulator which provides enough pressure for at least one full cycle if main hydraulic system pressure is lost.  Loss of electrical power disables the thrust reversers.
Environmental System

 The engines provide bleed air for pressurization and temperature control.  During normal operation, both engines provide bleed air which flows from the engines, thru heat exchangers, and finally thru a cooling turbine and into the cabin.  A bypass valve is installed that allows hot bleed air to bypass the heat exchanger and cooling turbine and mix with the air that has been cooled in order to regulate the temperature of the air entering the cabin.  The emergency pressurization is provided by the right engine bleed.  The heat exchanger & cooling turbine are bypassed when Emergency pressurization is selected.
 Additional cooling is available on the ground, and in flight below 18,000 FT through the use of an electrically driven freon air conditioning system.  Freon system should be off during takeoff.
Ice Protection


De-Ice Boots
Pneumatic with electric control.
Pitot Static
DC electric heat
Bleed air heat for stator and cowl
Fails "ON" with loss of electric power
Windshield Heat
Variable Frequency AC
Min 10 minutes LO before HI selected
HI only when LO is not effective

NOTE: To turn engine anti ice OFF, press ignitor button and reduce engine power to 90%, then turn engine anti ice switch to the off position.  Power may then be returned to 98% for the remainder of the climb.  Deviation from this procedure may result in engine flameout.  The flameout is caused by a pressure spike that results when the anti ice valves close.  This problem is most common when turning anti ice off above 15,000 to 20,000 feet.
Flight Profiles

    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 a 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 65% N1.
3.    Trim for level flight until passing 150 KTS.  Maintain altitude with necessary back pressure.
4.    At first indication of a stall,  throttles to " MAX POWER "
5.    Call " MAX  POWER Flaps 25 deg.
6     Reduce pitch ONLY to the extent necessary to eliminate symptoms of the stall.
7.    Reestablish assigned altitude.
8.    At Vref + 10 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 25 deg.
2.  Maintain assigned altitude and set power to 65% N1.
3.  Trim for level flight until passing 150 KTS.
4.  Maintain altitude and establish 25 deg bank angle.
5.  At first indication of a stall, advance throttles & call " MAX POWER ".
6.  Level wings & reduce pitch ONLY to the extent necessary to eliminate symptoms of the stall.
7.  Reestablish assigned altitude.
8.  At Vref + 10 KTS, call " Flaps Up, After Takeoff Checklist.  "
9.  Maintain AIRSPEED and altitude as directed.

Stall - Landing Configuration

1.    Slow to flap speed, set 80% N1 & Set bug to Vref.
2.    Maintain assigned heading & altitude.
3.    Below 160 KTS, " Flaps 15 deg".
4.    Below 180 KTS, " Gear Down Landing Check ".
5.    Flaps 25 deg
6,    Flaps - Landing
7.    Trim to Vref.  Establish a 400-700 feet/min sink rate at Vref.
8.    Level off at designated altitude  W I T H O U T  increase in power
9.    Maintain altitude until  first indication of a stall. (Shaker or aerodynamic buffet)
10.  Apply MAX power , call for "Flaps 25 deg, lower nose as required to eliminate the stall warning.
       then slowly 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 + 100 KTS, Call " Flaps Up, After Takeoff Checklist ".
13.  Return to entry heading and altitude or as directed.

ILS Approach - Two Engines

1.    Intercept LOC at 140-160 KTS and Flaps 25 deg.
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 - One Engine

1.  Intercept LOC at 140-160 KTS and Flaps 25 deg.
2.  Intercepting Glide Slope, call " Gear Down Landing Check ".
6.  Establish Vref + 15 KTS & track LOC & GS
7.  At 50 Ft AGL, Full flaps if desired, power as necessary & land.

Non Precision Approach - One or Two Engines

1.    Intercept Final Approach Course at 140 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 + 15 KTS until 50 feet AGL, then " Full
       Flaps" so as to perform a normal landing.

No Flap Approach

1.  Vref + 20 KTS until established on Final Approach.
2.  Vref + 10 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 pitch up, " Flaps Takeoff".
2.  Positive Rate of Climb, " Gear Up ", Vref + 10, " Flaps up, After Takeoff Checklist ".
3.  Climb at 200 KTS.
4.  Engine Failure or Fire Checklist if Appropriate.


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 ( 2 eng ) 10 deg ( 1 eng ).
5.  Climb at 15 deg pitch, ( 2 eng ) or V 2 ( 1 eng ).
6.  At 400 ft & V2 + 10 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.  Speedbrakes extend.
5.  Brakes as necessary.
6.  Thrust Reverse OR Dragchute deploy.  (Never Both!)
7.  If another takeoff is contemplated consider brake energy & appropriate turnaround time.

Note:  I do not recomend that you initiate a practice aborted takeoff at more than 40 knots, as it adds nothing to the value of the training, and may cause damage to the brakes and tires if performed imperoperly.

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.    Extend Speedbrakes
 7.    Initiate 45 deg bank if desired.
 8.    Vmo/Mmo minus 10 kts to 14,000 or MEA as required.
 9.    Clean up & proceed to nearest suitable airport if appropriate.  Condition of aircraft or
        reduced range due to low altitude may make flight to original destination unwise.

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