Please Read This Flight Manual

Document conventions

Credits and acknowledgments

End User License Agreement (EULA)


Installing Draken

Installing in Flight Simulator X

Uninstalling Draken

First startup

Texture resolution

About the model

Interior model

Exterior model

Repaint kit

Flight dynamics

Limits and restrictions

Inverted flight


Normal operating procedures

Before starting the engine

Starting the engine

Taxi and takeoff




Final approach and landing

Emergency procedures


Hydraulic system failure

Engine fire

Superstall recovery


Cockpit layout overview

Flight data system

Backup altimeter

Backup attitude indicator

Backup airspeed indicator

AOA indicator

G-force indicator


Cabin pressure indicator

Warning and indicator lights

Warning lights panel

Master Warning Light

Gear Warning Light

Communication radios

Radio control panel ME3

Radio control panel ME1

Radio control panel ME2

PN-837/A SSR transponder

PN-79 IK transponder

Navigation systems

FLI 35 system

PN-594/A system

Manual tuning unit


Autopilot modes

Trim knobs

Override conditions

Radar and weapons

Radar system



Hydraulic system

Electrical system

Emergency Power Unit (EPU)

Fuel system


Landing gear

Stall warning system

Oxygen system

Features and special effects

Options panel




Drop tanks

Drag chute

Contrails and smoke

Chocks and covers

Pilot animations

About Saab 35 Draken



Export versions

Appendix 1: J 35J check lists

Appendix 3: FR28 Radio channels

Appendix 4: PN-594 Nav stations

Appendix 5: Technical data

Appendix 1: Cockpit glossary

Electrical panels and switches

Engine panel

Warning lights


Radar and weapons panels

Circuit breakers

Appendix 6: Prepar3D commands

Flight Manual: Bookmark J 35J Draken 5.12021-04-24

Flight dynamics

The flight characteristics simulation or FDE (Flight Dynamics Engine) of this add-on is the result of many years of development by Bookmark Simulations, with the active participation and help of a number of former Draken pilots, mechanics and engineers.

As there are endless possible combinations of hardware and program settings out there the FDE will always be a compromise, and you probably need to customize the flight dynamics by editing the aircraft.cfg file to suit your own particular hardware setup.

There are a number of museums and event companies in Sweden that are using real Draken cockpits in their simulators with modified FDE files and special software. If you are planning to start your own cockpit project (non-profit or commercial), please contact Bookmark for further information about customization, licensing, and technical support.

Limits and restrictions

Draken is an excellent aerobatics performer provided that you understand the limitations of the design.

The double delta wing has good characteristics throughout the speed range, but it creates an exceptional amount of drag at high angles of attack. At AOA >15 the aircraft will typically not accelerate even with the afterburner engaged.

The use of combined elevators and ailerons - elevons - also means that maximum lateral (roll) authority is only available when the stick is pitch center, and vice versa.

In the transsonic speed range (M ~0.95–1.05) control response will be sluggish because of the high dynamic pressure on the large elevons. At low altitude you may be unable to pull more than 3 G.

To regain control response, reduce or increase your speed to get out of the transonic range.

Do not manoeuver close to the ground at transsonic speed.

Do not attempt split-S maneuvers above M 0.9 or 700 kmh. You may not be able to achieve enough angle of attack to recover from the dive.

Inverted flight

Flying inverted or with negative G is restricted to max 15 seconds to prevent fuel flow problems. Draken has buffer fuel tanks that will aid in keeping the fuel flow uninterrupted, but prolonged inverted flight may cause flameout. See also Fuel system.


Draken can go from stationary to supersonic in less than a minute. On the downside, speed bleeds off just as fast with rising angle of attack. When AOA approaches 15 you will lose speed and gain alpha at an alarming rate and may eventually end up in a deep stall/spin condition called Superstall.

Deep stall means an unrecoverable condition where all lifting surfaces on the aircraft have stalled (lost lift). Superstall is basically a deep stall with a spin component.

A delta wing does not stall gradually, like a straight wing does. At a certain angle of attack the whole wing area will lose lift without much warning. Delta winged aircraft therefore have a stall warning system that will alert the pilot before the critical AOA is reached.

When the stall warning is heard, pitch down immediately to reduce AOA and prevent superstall.

Superstall is not realistically simulated in this simulation due to limitations of the Prepar3D flight model, it is more a sort of tumbling spin. But close enough.