Flight Manual: Saab 35 Draken FSX 4.1Updated: 2014-12-22

System description

Cockpit overview

Warning and indicator lights

Hydraulic system

Electrical system

Emergency Power Unit (EPU)

Fuel system


Landing gear

Flight data system

FLI 35 system

PN-594 navigation radar



Other instruments

Stall warning system

Oxygen system

Radar system


Cockpit overview

The instrument panel uses the metric system (altitude in meters, airspeed in km/h, distance in kilometers). All gauges have tooltips that present the reading in both metric and US units.

Tooltips will not appear in fullscreen view if the Preview DirectX 10 option is enabled.

Most instruments and controls are present both in the 2D cockpit and in the Virtual Cockpit, with a few exceptions: The oxygen valve is only found in the VC, and the weapon quick-select switches on the radar hand control were left out from the VC as they are on the back side of the handle.

Virtual Cockpit

Some of the instruments and controls in the Virtual Cockpit would not be easily accessible if I used a realistic viewpoint and field-of-view, or if I put every little detail in its exact place. But in general terms I believe this is a decent rendering of the real cockpit.

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Fig. 40 -  Virtual Cockpit view

2D Cockpit

The 2D cockpit is by now just a legacy feature. It has not seen any major improvement to the bitmaps or layout for years, and I personally see very little point in using it compared to using the VC in forward view at normal zoom. Your choice, of course.

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Fig. 41 -  Cockpit view

At the bottom of the main 2D panel you will find information about the current navigation settings, engine functions, trim settings, radar mode and range, etc.

The functions of the icons are explained in their respective tooltips.

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Fig. 42 -  Additional info in cockpit view

Mini panelchanged in 4.1

The additional "mini panel" view shows some (fictional) HUD type instruments, including the radar and flight director. I find it useful for training final approach and landing when the view from the cockpit is obstructed due to the very high angle of attack. If you don't like it, don't use it.

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Fig. 43 -  Mini panel explained

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Fig. 44 -  Final approach using mini panel

Warning and indicator lights

Warning lights panel

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Fig. 45 -  Warning lights panel overview


Engine fire


Afterburner pump fire (not simulated)


Autopilot off or faulty


Engine heater on


Fuel system pressure fault


Low pressure fuel pump off or faulty


Engine oil pressure low


Exhaust nozzle operation


Oxygen valve off or tank empty


DC bus failure


Hydraulic circuit 1 pressure low (<5 MPa)


Hydraulic circuit 2 pressure low (<15 MPa)


Cabin air pressure low


Canopy unlocked

  • At ground idle the hydraulic pressure may be insufficient to deflect the elevons fully. Large movements of the stick may then momentarily cause a HYDR II warning and extend the EPU.

  • The EBK warning light is not an indicator for afterburner, it indicates that the exhaust nozzle eyelids are changing position. See also Engine.

  • The STYRAUT warning light indicates autopilot failure, not that the autopilot is active. It will also be lit if you switch off the autopilot main switch.

Master Warning

The Master Warning light (red) will blink if any of the other warning lights are lit, with some exceptions:

  • The Engine Deice indicator light (MOTOR IS) will not cause a Master Warning.

  • The EBK warning light will normally not trigger a Master Warning.

  • When the emergency bus is switched on, the Electrical Failure (ELFEL) warning will still be lit, but the Master Warning will disappear.

  • The Fuel System (TANK LUFT) warning sometimes lights up for a few seconds when the system switches from external to main fuel tanks. This will not cause a Master Warning.

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Fig. 46 -  Master Warning light

Gear Warning

The Gear Warning Light light (orange) blinks while the main gear is being extended or retracted. It will also blink if the gear is not extended when airspeed is less than 450 kmh at less than 1450 m altitude, and throttle is less than 85–90%. See also Landing gear.

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Fig. 47 -  Gear Warning light

Hydraulic system

The hydraulic system has three pumps feeding two circuits:






1 + 2

210 kp/cm2 (20 MPa)

Gear, wheel brakes, nozzle, speed brakes, autopilot, control surface servos



210 kp/cm2 (20 MPa)

Nose gear steering, control surface servos

Each hydraulic circuit has a corresponding low pressure warning light:

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Hydraulic pressure in circuit I less than 5 MPa

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Hydraulic pressure in circuit II less than 15 MPa

When the engine is not running and the aircraft is motionless there is no hydraulic pressure. All control surfaces (including air brakes) are inoperable, and the elevons will be fully deflected downwards. When the engine spools up, the elevons will slowly rise to neutral position and all control surfaces become operable.

If the pressure in circuit II falls below 17.5 MPa, a backup hydraulic pump driven by a ram air turbine, the Emergency Power Unit (EPU), is automatically deployed. The backup pump will supply enough hydraulic pressure for the control surface servos (provided that the aircraft has enough airspeed). The EPU is automatically retracted when the pressure in circuit II exceeds 18.1 MPa.

At ground idle, large stick movements may cause the pressure in circuit II to momentarily fall below the threshold value, which will set off the HYDR II warning light and extend the EPU. This is normal and not a hydraulic system fault.

Wheel brakes

The wheel brakes are hydraulic self-adjusting anti-lock disk brakes. Normal brake pressure is 210 kp/cm2 (20 MPa). At least 60 kp/cm2 (5.9 MPa) is needed for effective braking. Brake pressure is provided by hydraulic pumps 1 and 2.

The hydraulic pressure in the brake circuit is shown by the brake pressure indicator on the right knee panel.

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Fig. 48 -  Brake pressure indicator

Extending gear at high airspeed may damage the wheel brake hydraulics.

In FSX the anti-skid brake function is for some reason disabled unless you specifically switch it on. In this simulation it is automatically enabled.

Electrical system


Electrical system specifications


200 VAC/400 Hz/20 kVa

Emergency alternator

200 VAC/400 Hz/3.5 kVa

Power consumption (typical)

16 kVa


24 V/6.5 Ah

Bus name Voltage BATT ALT


Hot Battery Bus

24 VDC




DC Main Bus

29 VDC




DC Normal Bus

29 VDC




AC Main Bus

3 x 200 VAC




AC Normal Bus

3 x 200 VAC




Instrument Bus

3 x 45 VAC




The alternator is connected directly to the engine turbine shaft and has a regulator which keeps AC voltage and frequency constant regardless of engine speed.

Before the engine has been started, electrical power is normally supplied by an APU (Auxiliary Power Unit). Starting can also be done using only the aircraft battery as power source. In this version the APU is not implemented, and the battery is used for starting.

A backup alternator driven by a ram air turbine supplies power to the Main and Instrument buses in case of engine failure. See Emergency Power Unit (EPU).

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Fig. 49 -  Engine control panel – electrical bus switches

Electrical failures

DC bus failures are indicated by the ELFEL warning light on the warning lights panel. This warning light will also be lit when the backup alternator is connected.

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Fig. 50 -  DC bus failure warning light

AC bus failures are indicated by a mechanical indicator on the Airspeed/Mach Indicator. A white field means that AC power is not available.

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Fig. 51 -  AC bus failure indicator

Electrical panels

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Fig. 52 -  Electrical system control panels


Navigation lights. Four-way switch, center position is OFF. HEL = bright, HALV = dimmed, BLINK = blinking (seldom used).


Dimmer for all warning and indicator lights.

HALVLJUS = dimmed, HELLJUS = normal.


Push to test all warning and indicator lights.


Emergency electrical bus.

See also Emergency Power Unit (EPU).


Engine de-ice. Use only before take-off.

MOTOR IS warning light is lit when activated.


Canopy de-ice. Three-way switch, center position is OFF. Should be switched on during descent and approach.


Air conditioning control panel. Not implemented in this version.

Circuit breakers

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Fig. 53 -  Circuit breaker panel

All electrical circuit breakers should be ON (up) at startup, although only three of them have any function in this version. The first four should be switched off at shutdown, the rest are normally always left on.

Speed Brake Trim engages the upper speed brakes to work in conjunction with the elevons. This enables higher G load in the transsonic speed range, where the high dynamic pressure limits elevon movement. When Speed Brake Trim is active, adjusting pitch trim will affect the position of the upper speed brakes.

Speed Brake Trim is not implemented in this version.

Interior lights

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Fig. 54 -  Interior lights panel


Interior lights


Direct lighting of panels (not implemented)


Backlighting of panels and instruments

The dimmers work only as on/off switches in this version.

Emergency Power Unit (EPU)

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Fig. 55 -  Emergency power unit

The Emergency Power Unit (EPU) is a ram-air turbine driving a backup alternator and a hydraulic pump.

The backup alternator supplies 3.5 kVA and is tied automatically to the main AC bus when the EPU is deployed. The backup hydraulic pump has enough capacity to supply the most crucial functions.

The EPU will deploy automatically when the pressure in hydraulic circuit drops below the threshold value and/or the AC bus is powerless (engine stopped).

The EPU can also be deployed manually by toggling the Emergency Bus (NÖDSTRÖM). When the switch is on, the electrical system warning light is lit on the warning lights panel. The switch should always be off under normal flight conditions.

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Fig. 56 -  Emergency bus switch

The EPU will only supply electrical and hydraulic power if airspeed is sufficiently high. In this simulation the lower limit is set to 100 kmh (54 kts).

Fuel system

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Fig. 57 -  J 35J with 4 external tanks

The fuel system consists of a low pressure system which includes the fuel tanks, fuel pumps and distribution system, and two high pressure systems that include fuel injection pumps, regulators and nozzles for the engine and afterburner.

The low pressure fuel system is controlled with valve switches on the engine control panel while the high pressure system is controlled by the throttle handle.

The purpose of the low pressure fuel pumps is to raise the fuel pressure to a suitable level for the engine injection pump. They are powered from the AC bus and will only work when either the alternator or the EPU are providing power. A separate pump powered from the DC battery bus is used when starting the engine.

Flying inverted or with negative G more than 20 seconds may result in flameout due to uneven fuel pressure.

Fuel tankschanged in 4.1

J 35J has two internal tank groups, forward and rear, with a total capacity of approximately 2700 litres. Each tank group also has a small buffer tank that will facilitate fuel flow in inverted flight. Two external (drop) tanks with 525 litres each can be fitted under the fuselage.

J 35J could also be fitted with two additional drop tanks on the wet outer wing pylons. Wing tanks are not implemented in this version.

The external tanks can be jettisoned with the FSX key command Drop Tanks 1. See also Drop tanks.

In the FSX fuel dialog the forward and rear tank groups are listed as Center and Center 2, the buffer tanks as Center 3, and the fuselage drop tanks as External 1.

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Fig. 58 -  FSX fuel dialog

Fuel control

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Fig. 59 -  Fuel system controls

The Main Fuel Valve and Reheater Fuel Valve switches on the Engine Panel control the low pressure fuel valves for engine and afterburner. Both switches must be ON during flight. The LT warning light will be lit when either of these switches are OFF.

The Drop Tanks Indicator shows two white fields when the External Fuel Valve switch is ON and there is fuel in the external tanks.

The External Fuel Valve switch, or fuel mode switch (MÄTSYSTEM FTANK), controls the low pressure fuel valves for the external tanks.

When the External Fuel Valve switch is OFF, fuel is supplied from the main tanks, alternating between front and rear groups to maintain the center of gravity. The fuel gauge needles for the forward (F) and rear (B) groups should not differ more than 5%.

When the switch is ON, fuel is supplied from the external tanks. The fuel gauge indicates the level of remaining fuel in the external tanks, with 40% as maximum (80% with wing tanks). When the external tanks are empty or the External Fuel Valve switch is OFF, the external fuel valves close and the main tank valves open. The fuel gauge will automatically switch to measuring the main tanks, and the white fields on the Drop Tanks Indicator will disappear.

If the External Fuel Valve switch is ON when the engine is started, the external fuel tanks will not be available after starting.


The engine in J 35J is a Volvo Flygmotor RM6C, which is an upgraded license-built Rolls-Royce Avon 300 Mk. 60 turbojet with a Swedish single-stage EBK-67 afterburner.

The afterburner adds thrust to the engine by injecting additional fuel into the exhaust section. The ignited fuel raises the exhaust gas temperature, which increases the exhaust gas volume and speed. The exhaust nozzle area is widened when the afterburner is active to prevent the exhaust gas speed from exceeding Mach 1.

The engine control panel is located beside your left knee in the cockpit, just in front of the throttle lever. The panel is described in Before starting and Starting the engine.

The alternator switch is spring-loaded. Push UP and hold for 1–2 seconds to switch the alternator ON. Push DOWN to switch it OFF.

The AC bus relay will only be actuated when engine speed is above 30 %. If engine speed falls below 27 %, the relay will drop and an AC bus error is indicated.

Engine control panel

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Fig. 60 -  Engine control panel – overview

Exhaust temperature control

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Fig. 62 -  Exhaust temperature control

Exhaust gas temperature regulator (MAX TEMP)

The exhaust gas temperature regulator automatically reduces fuel flow to the engine if EGT exceeds 750° C to protect the engine from damage by overheating.

The regulator should normally be enabled (TILL), but can be disabled (FRÅN) to prevent loss of thrust during combat or under critical conditions.

Exhaust nozzle regulator (RAT)

The exhaust nozzle regulator opens the exhaust nozzle eyelids fully to prevent overheating when the aircraft is on the ground and the throttle is at ground idle. The EBK warning light will be constantly lit in this mode. The nozzle will revert to the normal position once the throttle is above ground idle.

The RAT function should normally be enabled (TILL). It is automatically disabled when the aircraft is airborne.

The RAT function should not be confused with the ram air turbine, which in other circumstances is usually abbreviated RAT.

Landing gear

The landing gear consists of a main gear, a nose gear, and a spurwheel. The spurwheel protects the tail end as Draken has a very high attitude on landing. The landing gear is normally extended and retracted using hydraulic pressure from hydraulic circuit I, see Hydraulic system.

The main and nose gear are locked mechanically in both the extended and retracted positions. The spurwheel is hydraulically locked in the extended position and held in place by the spurwheel hatches when retracted.

A mechanical lock prevents the gear lever from being moved from the "gear extended" position if the throttle is at less than 90%.

The lights on the Gear Indicator are lit when the respective gear mechanisms are locked in the extended position.

The Gear Warning light (orange) blinks while the gear is being extended or retracted. It will also blink if the gear is not extended when airspeed is less than 450 kmh at less than 1450 m altitude and throttle is less than 85–90%.

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Fig. 63 -  Landing gear indicator and warning lights

If hydraulic pressure in the gear circuit is lost, the gear can be extended using gravity and then locked using compressed air from an accumulator. The pneumatic lock is activated with a lever on the left side console. See also Hydraulic system failure.

Flight data system

The final version of Draken was a combination of old-school aircraft engineering and high-tech military avionics. The navigation, communication, flight control and weapons delivery systems in J 35J were closely integrated, interacting with ground mission control (STRIL) via data link.

The flight data system in J 35J consists of a data I/O unit, a Central Processing Unit (CPU), sensors, monitors, control panels and indicators for airspeed, altitude, navigation and targeting data. The CPU processes the signals from the sensors and monitors, radar and data link, and presents information on the various indicators and on the radar screen.

Airspeed/Mach indicator

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Fig. 64 -  Airspeed/Mach indicator unit

The Airspeed/Mach Indicator is controlled by the CPU, which reads the nose pitot tube pressure.

The Mach scale is linear between M 0.5–2.0, with an index at cruise Mach (M 0.9).

The Vi scale is linear from 150–350 kmh and logarithmic from 350–1400 kmh. The scale has indices for V2 (270 kmh), Vref (375 kmh), and VNE (1350 kmh).

A white rectangular field on the lower part of the airspeed scale indicates AC bus failure. The indication disappears when the engine speed exceeds 27 % and the alternator bus is switched on.

Distance/Altitude/Command indicator

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Fig. 65 -  Distance/Altitude/Command indicator unit

The left scale shows the distance to the currently selected navaid in ranges 0–40 km or 0–400 km depending on the setting on the PN-59 control panel, see PN-594 navigation radar.

The right scale shows the standard pressure altitude in meters at 1013.25 hPa (QNE). The tape indicator indicates thousands, the dot indicates hundreds.

The small arrow indicates target altitude (not implemented in this version).

The window at the top shows STRIL mission control information (not implemented in this version).


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Fig. 66 -  Altimeter

The altimeter shows the pressure altitude in meters, calculated by the flight computer. The needles are driven by an electrical stepper motor, which means that needle movement is not fluid but in small increments and the reaction can be slightly delayed.

To set the altimeter, place the cursor on the pressure setting knob and rotate the mouse wheel. Pressure setting is in millibars (hPa).

FLI 35 systemChanged in 4.1.1

The FLI 35 system is a spatial data processing/presentation system comprising the main gyro, the attitude and horizontal situation indicators, and a waypoint navigation system. FLI 35 processes data from the gyro, sensors and monitors, and presents information to the pilot. The system automatically compensates for magnetic deviation and gyro drift.

Ten navigation waypoints (in Sweden) can be stored by entering their waypoint codes. The computer will calculate course, distance and estimated fuel consumption to the active waypoint and present it on the FLI 35 Indicator unit.

In this simulation, 45 pre-set waypoint codes are available. See Appendix 3: PN-594 Navigation channels.

Attitude indicator

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Fig. 67 -  Main attitude indicator

The main attitude indicator is electrical and is connected to the main gyro via the FLI 35 processor. In case of a malfunction in the FLI 35 system there is also a backup attitude indicator which is connected to a separate gyro. See Other instruments.

Course/Heading indicator

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Fig. 68 -  Course and heading indicator

The Course and heading indicator is basically a HSI without any VOR indication. It has a rotating scale showing the magnetic heading, and a course indicator needle which is either commanded by the flight computer or set manually with the Course selector.

The instrument is powered by the AC bus. The scale and needle will freeze when AC power is off.

Unlike in previous versions of this simulation, the instrument does no longer indicate bearing to navaids or waypoints. Course commands from STRIL are not simulated.

Course selector

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Fig. 69 -  Course selector

The Course selector is used to set the course on the Course and heading indicator. It basically corresponds to the OBS setting in VOR navigation.

FLI 35 Indicator unit

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Fig. 70 -  FLI 35 Indicator unit


Press repeatedly to cycle through waypoints 1–10.


Calculated distance/bearing to the selected waypoint is shown alternatingly for 2 seconds. To avoid confusion, course is always shown with three digits (000–359).


Estimated fuel consumption to the WP is shown as a percentage of total capacity, external tanks included.


Updates WP with the current position (not implemented).

FLI 35 Control unit

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Fig. 71 -  FLI 35 Control unit

The FLI 35 Control unit is used to select the FLI 35 Indicator unit presentation mode and for entering waypoints. See Appendix 3: PN-594 Navigation channels for a list of available waypoints.

    Storing FLI 35 waypoints
  1. On the FLI 35 Control unit, set the Mode Selector to IN B/LS.

  2. On the FLI 35 Indicator unit, press B/LS to select a waypoint.

  3. On the FLI 35 Control unit, press CLR.

  4. Use the keypad to enter a waypoint code (e.g. 9010 for Ängelholm AB).

  5. Press ENT to store the waypoint.

  6. Press B/LS to select another waypoint and repeat steps 3–5 as needed.

  7. When finished, set the Mode Selector to NORM.

PN-594 navigation radarChanged in 4.1

J 35J did not have standard VOR/ILS capability, but used query/response signaling systems between the aircraft and ground stations for long-range navigation and landing guidance, respectivelly nicknamed Anita and Barbro. The aircraft transceiver queried the ground station, and the response signals were processed by the on-board computer and fed to the Flight Director.

Draken 4.1 includes a scenery with VOR/ILS navaids that simulate Anita and Barbro. The scenery must be activated after installation.

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Fig. 72 -  Barbro and Anita scenery objects

The Anita station basically works as a long-range DME. The maximum range is 400 km (216  NM), the actual range of course depends on altitude and terrain.

Unlike an ILS localizer, the Barbro station is located slightly offset from the runway. The approach path deviates from the centerline by a few degrees and intersects it at a point 800 m out from the touch-down point. The glide path is 2.86°, not 3.0° as in standard ILS. The maximum range of the Barbro station is 30 km (16  NM).

To fly an approach, set the desired Barbro station on the LANDN dial of the PN-59 unit and select LANDN40, then keep the vertical crossbar centered. You will be guided in an optimal turn to a point intersecting the centerline. To capture the signal you need to be within a 72° sector of the approach and within range of the Barbro station.

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Fig. 73 -  Flying a LANDN 40 approach

PN-59 Control Panel

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Fig. 74 -  PN-59 control panel

The NAV dials are used in combination to select the two-letter ANITA station code.

The LANDN dial selects the BARBRO station. As the BARBRO stations have a relatively short range, a one-letter code is sufficient for separation.

See Appendix 3: PN-594 Navigation channels for a complete list of ANITA/BARBRO codes and frequencies.

When standard navigation is selected (see Manual tuning unit), the Distance Indicator and the Flight Director will use standard VOR/DME/LLZ/ILS, and the NAV/LANDN dials are ignored.

STRIL (ground control) commands are not implemented in this version.

Mode DME scale Vertical FD bar Horiz FD bar












In reality: STRIL.










NAV 400

400 km



NAV 40

40 km




40 km

BARBRO/LLZ intercept

BARBRO/ILS glide slope


40 km

BARBRO/LLZ deviation


The distance indicator shows the distance to the ANITA station in NAV40/400 mode but to the TDZ in LANDN40 and BARBRO modes.

Flight director

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Fig. 75 -  Flight director crossbars

In BARBRO mode the vertical bar will act like a standard LLZ indicator, while in LANDN40 mode it will guide you into an optimal turn to the final approach. The position of the vertical bar will change as you switch between these modes, unless you are exactly on the localizer course.

Test button

To test the Flight Director, select NAVRIKTN and push the TEST button on the PN-59 control panel. The vertical crossbar should move to the center.

Manual tuning unit

Navigation with standard FSX navaids is facilitated with a Collins-style tuning unit, which here is also used to switch between PN-59 and manual tuning.

This unit is completely fictious as the real J 35J had no VOR/ILS equipment.

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Fig. 76 -  Navigation radio selector / manual tuning unit

Radioschanged in 4.1

Draken has two radio transceivers for voice and data communication: FR28 (UHF/VHF) and FR21 (VHF). FR28 is used for voice communication. FR21 is normally used for data but can also be used for voice as backup. In this simulation, FR28 basically corresponds to COM1 and FR21 to COM2.

FR28 also had independent monitoring on the emergency channel 121.50 MHz. In this simulation we use COM2 for that (see table below).

The radios are connected directly to the main electrical bus and have no master switch. The radio control panels ME1, ME2 and ME3 are used in combination to control FR28/FR21 (COM1/COM2) as follows:


Real J 35J







Voice - set by ME1

121.50 MHz monitored

Data - set by ME2

ATC set by ME1

121.50 MHz


Set by ME1


ATC set by ME1

Receiving only



Set by ME3

Receiving only

ATC set by ME3

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Fig. 77 -  J 35J radio stack

The real FR-28 used frequency ranges 103.000–159.975 MHz in VHF and 225.000–339.950 MHz in UHF. FSX only supports VHF frequencies 118.00–121.75 MHz.

Radio control panel ME1

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Fig. 78 -  Radio control panel ME1

On this panel you can select one of 350 preset channels for TWR, TMC, etc. at 69 Swedish air bases. See Appendix 2: FR28 Radio channels for a list of airfields and channels.

When the minus key (–) is pressed, the frequency can be set manually with the two knobs to the left of the LED frequency display.

Accepting a frequency change in ATC will always override the current preset or manual setting.

The FM/AM switch has no function in this version.

The left dial and the numerical keys on the lower half of the panel are for tactical radio channels. They are not functional in this version.

Radio control panel ME2

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Fig. 79 -  Radio control panel ME2

The ME2 control panel has eight keys and a dial to select STRIL data communication channels for the FR21 radio transceiver.

The + key sets automatic channel selection (default).

The - key disables the channel selector. ME3 is then used to set the frequency for FR21.

As STRIL is not implemented in this version, the ME2 panel has no actual function.

Radio control panel ME3

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Fig. 80 -  Radio control panel ME3

This panel is used to select communication radio modes and as a frequency selector for FR21 when the - key on the ME2 control panel is pressed.


Radio mode select, see table above.


Toggles between omni and rear-facing antenna.


Press for 1 KHz test signal.


Wired ground com (not implemented).

The red warning light indicates radio failure. Push the lamp to test.

PN-837/A SSR transponder

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Fig. 81 -  PN-837/A SSR transponder

The PN-837/A SSR transponder operates in the civilian modes 3/A and C.  


Normal mode (default)


Transponder on but not transmitting


Transponder sensitivity reduced with -14dB


Push to enhance signal from aircraft for identification


Indicates query/reply transmission


MON = RPLY indicator lit on query/reply

0 = RPLY indicator disabled

TEST = Test RPLY indicator (steady light)


Mode C altitude transmit on/off (not used)

PN-79 IK transponder

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Fig. 82 -  PN-79 transponder

The PN-79 transponder is a military IFF unit operating in encrypted mode.

IFF is not implemented in this simulation, this panel is just a dummy.

Autopilotchanged in 4.1

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Fig. 83 -  Autopilot control panel

The SA-05 autopilot has only three modes: Altitude Hold (HÖJD), Attitude Hold (ATTITYD), and Pitch Damping (DÄMPN).

Unlike the standard FSX autopilot, the SA-05 autopilot is engaged automatically when you load the aircraft, although none of its hold modes are active. In the real Draken the master switch was actually sealed in the ON position (TILL) and only switched off (FRÅN) in an emergency.

The reason for this is that the autopilot in Draken handles the pitch damping function, making the aircraft less susceptible to PIO (pilot induced oscillation) that plagued the early versions of Draken. The damping mode was supposed to be switched on at all times. In this simulation pitch damping is actually a part of the FDE and can not be disabled.

The altitude and attitude hold modes will disconnect automatically under certain flight conditions, see Autopilot override conditions. No acoustic warning is given.

Altitude hold mode (HÖJD)

In this mode the aircraft will lock to the current altitude. If the bank angle is less than 15 degrees when this mode is activated, the wings will also be leveled. The HÖJDV indicator light (altitude hold) will flash until altitude is stable, then it will show a steady light. The SVÄNG (turn setting) knob on the autopilot control panel will bank the aircraft left/right in 15 degree increments.

In the transsonic speed range (M 0.95–1.05) the autopilot will change temporarily to attitude hold mode, and the HÖJDV warning light will flash. When the aircraft exits the transsonic speed range, the autopilot will change back to altitude hold mode. The mode indicator on the autopilot panel will not change.

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Fig. 84 -  Altitude hold light

Attitude hold mode (ATTITYD)

In this mode the aircraft will hold the current pitch attitude. If the bank angle is less than 15 degrees when this mode is activated, the wings will also be leveled. The Pitch Adjust lever will adjust pitch up/down in 1 degree increments. The Turn Setting knob will bank the aircraft left/right in 15 degree increments.

Damping mode (DÄMPN)

Pitch and yaw damping. This is the default mode which should always be on in manual flight to prevent PIO (Pilot Induced Oscillation).

Trim knobs

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Fig. 85 -  Roll and yaw trim

The Roll Trim and Yaw Trim knobs will adjust roll and yaw trim in 10 % steps. Trim setting will affect the control surfaces regardless of the autopilot status, and is added to the current roll/yaw attitude in altitude/attitude hold modes.

Autopilot override conditions

In altitude and attitude hold modes the autopilot will disconnect automatically if the joystick is moved abruptly, if one of the attitude indicators is caged, or if G force is above 4 G or below -0.5 G. The autopilot warning light STYRAUT and the master warning light will then light up. There is no acoustic warning.

To reconnect the autopilot and reset the warning lights, press one of the mode select buttons on the autopilot control panel.

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Fig. 86 -  Autopilot warning light

The G force override function can be tested with the PROV ACC BRYT switch located on the far right knee panel. Pressing the switch upwards (+) simulates a high positive G condition, and vice versa.

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Fig. 87 -  Autopilot override test switch

Autopilot test panel

A test panel for the autopilot is located on the right wall of the cockpit. Its functions are not implemented in this simulation.

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Other instruments

AOA indicator

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Fig. 89 -  AOA indicator

The AOA indicator shows the current alpha angle of attack, which is the angle between the wing chord line and the current movement vector. Drag increases quickly with increasing alpha angle, so this indicator is crucial for maintaining control of the aircraft.

The Stall warning system will alert the pilot if the angle of attack exceeds a limit value.

Superstall (total loss of lift) will occur at AOA >18.

G-force indicator

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Fig. 90 -  G-force indicator

The G-force indicator, or G-meter, shows acceleration force in the range -1.5 to +11.5 G. The indicator has a maximum needle which is reset by pushing the reset button on the right side of the meter.

An acoustic warning signal is triggered at approximately +6 G.

The G-force indicator is disconnected when the aircraft is on the ground.


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Fig. 91 -  Chronometer

The aircraft chronometer is electrical and shows the current local time in hours/minutes. It has a stopwatch function and a moving index used to monitor flight time.

Before take-off, turn the index ring to align the index with the minute hand. The duration of the flight can then be read from the position of the minute hand vs. the index.

The stopwatch pushbutton will successively start, stop, and reset the stopwatch.

Backup attitude indicator

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Fig. 92 -  Backup attitude indicator

The backup attitude indicator is connected to a separate gyro and provides attitude information in case of a malfunction of the FLI 35 system.

Backup altimeter

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Fig. 93 -  Backup altimeter

The backup altimeter is located on the left knee panel. The indicator is mechanical and directly fed from an aneroid. It is completely separate from the main altimeter and has its own pressure setting.

Backup airspeed indicator

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Fig. 94 -  Backup airspeed indicator

The backup ASI is located on the left knee panel. It shows indicated airspeed from 150–1200 kmh. The backup ASI is completely mechanical and is connected to the stab fin pitot tube, while the main ASI via the flight computer is connected to the nose pitot.

Pitot tube heating is controlled separately for the nose and fin pitots. Make sure that you enable both when needed.

Cabin pressure indicator

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Fig. 95 -  Cabin pressure indicator

The cabin pressure indicator is located on the left knee panel. It shows the pressure difference between ambient pressure and cabin pressure.

Cabin air pressure is regulated by a pressure regulator. The pressure difference should be zero up to 3000 m altitude, and then increase with altitude to a maximum of ~0.25 kp/cm2 (24.5 kPa) at 6400 m.

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If the pressure difference exceeds 26 kPa, the KABINTRYCK warning light will be lit.

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Fig. 97 -  Cabin pressure warning light

Stall warning system

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Fig. 98 -  Stall Warning System

The Stall Warning System will warn the pilot when the angle of attack of the wing is approaching a critical value.

The system has two modes: NORMAL and EARLY. In NORMAL mode, the stall warning alert will sound at AOA = 15.5, and in EARLY mode at AOA = 14.

Stall warning test

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To test the stall warning system, press the STALLV. TEST button on the left side console. The angle of attack indicator will move first to zero, then climb to just below the selected stall warning value (Normal or Early). Applying back pressure at this point should trigger the stall warning.

Oxygen system

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Fig. 100 -  Oxygen control panel

The oxygen system supplies a mixture of oxygen and air to the pilot's breath mask. The mixture is automatically regulated depending on the cockpit air pressure. At an air pressure corresponding to 9000 meters altitude the system will supply pure oxygen.

The oxygen pressure indicator on the right side console indicates the pressure in the oxygen tanks, which should be at least 80 kp/cm2.

The oxygen shut-off valve is located to the left of the oxygen pressure indicator. If the oxygen valve is closed, or if the oxygen tank is empty, the SYRGAS warning light will be lit.

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Fig. 101 -  Oxygen warning light

Radar system

The radar in J 35J was an Ericsson PS-011/A radar, which was a major upgrade of the older Ericsson PS-01/A system used in J 35F.

The radar functions in this simulation are not even close to the real radar system, although the range and scan modes are roughly similar. The radar screen will display AI and multiplayer aircraft, but no ground or sea objects. Targeting functions and weapons delivery are not implemented.

The radar will only transmit when the aircraft is off the ground. When the nose gear is compressed, the radar will automatically be switched to silent (non-transmitting) mode.

Radar screen

The radar screen presentation mode is either B-scope or Tactical Mode (F-scope). Mode switching was automatic during a mission depending on the situation and data from mission control (STRIL). In this simulation you toggle manually between F-scope and B-scope modes with the KONTR switch on the Radar control panel (this switch was in reality only for testing purposes).

The radar has two distance ranges, 16 km and 40 km, and two sweep widths, 40 and 120. Antenna elevation can be adjusted, although it has no effect in this simulation.

An artificial horizon is displayed on the screen when the radar is active or in standby mode. The gain (brightness) of the CRT screen can be adjusted with LJUSSTYRKA F-SKOP on the Weapons control panel.

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Fig. 102 -  Radar screen

In the 2D cockpit view, the selected range and mode settings are also displayed in the panel icons area at the bottom of the main panel.

Radar control panel

The radar control panel is located on the left side wall of the cockpit. Only two of the switches are functional in this simulation.

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Fig. 103 -  Radar control panel

The B-scope/F-scope toggle switch was in reality a test mode switch, but in this simulation we use it to manually select presentation mode.

Weapons control panel

The weapons control panel on the right side wall of the cockpit contains the radar master switch and the CRT gain (brightness) control. The FPLF switch selects whether the antenna should be gyro-stabilized (always horizontal) or fixed (moving with the aircraft).

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Fig. 104 -  Weapons control panel

Radar control handlechanged in 4.1

The radar control handle is a joystick located on the left side. Moving the control handle would move the cursor on the radar screen (not implemented in this version). The switches on the handle are used for quick-selecting targeting modes and weapons, see Selecting and deploying weapons

The antenna height adjustment has no effect in this version except for moving the antenna height marker on the scope.

The target aquire and targeting mode switches are not functional in this version.

The weapon quick-select switches are only functional on the 2D panel, as they are partly obscured in the Virtual Cockpit.

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Fig. 106 -  Radar control handle


Loadout configuration

The weapons shown in the exterior model can be changed using the Loadout Configuration panel.

Earlier versions of Draken (J 35A/B/D) had two 30 mm Aden cannons, but to make space for more avionics the left cannon was removed in models F/J. The 35J had a total of 6 hardpoints for Sidewinders, IR/RR Falcons and air-to-air rockets. Air-to-ground rockets and free-fall bombs could also be fitted, although AFAIK they were never used with 35J.

In this simulation there are 9 preset loadout configurations available, named J1 to J9. You can choose between three different Sidewinder models for each of the base configurations.

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Fig. 107 -  Loadout configuration panel




Clean aircraft (no loadout)


2 Rb 27 (Radar-homing Falcon), 2 Sidewinders


1 Rb 27, 1 Rb 28 (IR-homing Falcon), 2 Sidewinders


2 Rb 28, 2 Sidewinders


1 Rb 28, 3 Sidewinders


1 Rb 27, 3 Sidewinders


Wing tanks, 2 Sidewinders (separate model)


6+6 13.5cm A-G rockets, 2 Sidewinders


2+2 13.5 cm A-G rockets, 2 Sidewinders


19+19 7.5 cm A-A rockets (pods), 2 Sidewinders

Rb 24

AIM-9B Sidewinder

Rb 24J

AIM-9J Sidewinder

Rb 74

AIM-9Li (Swedish modified AIM-9L)

Selecting and deploying weaponschanged in 4.1

Selection and configuration of ordnance is carried out using the Weapons Control Panel and the Radar Control Handle. Deployment is aided by the Radar system and Gunsight.

The Radar Control Handle has two switches for quick-selecting the cannon or RR/IR targeting missiles. Quick-select will work while the Weapons Selector is in any position except FRÅN (off). Press the Reset switch on the hand control to revert to the previously selected mode. Changing the setting of the Weapons Selector will also cancel quick-select.

The Weapons Indicator to the left of the gunsight shows which weapon is currently selected. Indicator lights R and I will be disabled if RR or IR targeting missiles are not mounted.

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Fig. 108 -  Weapons selection and indication






Fire control system off

RB 24


Sidewinders on belly hardpoints



Automatic cannon



Radar targeting only



Falcons, radar targeting



Falcons, infra-red targeting

RAK + RB 24


Rocket pods/Sidewinders on wing hardpoints

All weapons can be mounted and selected in this version, but only the cannon can be fired. It will not cause damage to AI or multiplayer aircraft.


The S-7B3/31 reflector gunsight in J 35J was integrated with the avionics and radar systems, and could be used in either radar-aided or optical mode. It provided aiming information for A/A missiles in radar-aided mode, and for the cannon and A/G missiles in optical mode.

This simulation only includes the optical mode with gyro aiming (diamonds and pipper). Targeting is not implemented. The gunsight will be activated if the Weapons Selector is set to either AKAN (cannon) or any of the missile launch modes, see Selecting and deploying weapons.

The targeting range (radius of the circle of diamonds) can be changed with the adjusting knob on the right side of the gunsight assembly.

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Fig. 109 -  Gunsight in J 35J

Cannonadded in 4.1

The 30 mm Aden automatic cannon is the only functioning weapon in this version. It is only a visual/sound effect and will not cause damage to AI or multiplayer aircraft.

The cannon is fired using the FSX APU START command, which can be assigned to a key or button on your controller (assign it as Repeated).

To enable the cannon, select AKAN on the Weapons Selector or use the quick-select (SNAK) on the Radar Control Handle.

The fire control system is disabled until the landing gear has been retracted.

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Fig. 110 -  Cannon firing tracer ammo