Start here
A few places to begin, from the aircraft’s story to the people who fly it.
Aircraft and simulator background
The SF-37 is the reconnaissance member of Saab's Viggen family. Canards, retractable landing gear, one jet engine and a reversing system form the configuration represented by DeltaWing Simulations.
Saab SF-37 Viggen
DeltaWing Simulations · Read more ↗Hydraulic handling and SPAK
DeltaWing describes custom hydraulic handling and SPAK control augmentation for its SF-37. Its product also identifies CK37 and autopilot systems. Those features belong to the reconnaissance simulation; AJ37 and JA37 equipment are separate variant references.
Saab SF-37 Viggen
DeltaWing Simulations · Read more ↗Airframe configuration
The represented SF-37 has one jet engine, canards, retractable gear and a reversing system.
Saab SF-37 Viggen
DeltaWing Simulations · Read more ↗Meet Saab SF-37 Viggen
The SF-37 is the reconnaissance member of Saab's Viggen family. Canards, retractable landing gear, one jet engine and a reversing system form the configuration represented by DeltaWing Simulations.
The X-Plane 12 product describes custom hydraulic handling, SPAK augmentation, a CK37 computer and autopilot functions.
Saab SF-37 Viggen
Saab SF-37 Viggen
DeltaWing Simulations · SF-37 Viggen — DeltaWing Simulations reference ↗Aircraft type designators
No type designator selected for this reference.
History & design
A Swedish system, not just an airframe
Saab dates the decisive System 37 design choices to 1961–62. The first Viggen flew at Linköping on 8 February 1967, and deliveries began in 1971. The canard-delta configuration and onboard computer served a programme intended to combine demanding military roles with operation from short runways.
Saab · Viggen: three decades in Swedish service ↗Saab historical account, 22 June 2021; SF 37 distinguished from the wider family
The letters distinguish the mission
The family included the AJ 37 attack aircraft, SH 37 maritime reconnaissance aircraft and SF 37 photographic reconnaissance aircraft. The two-seat Sk 37 served training, while the JA 37 was the fighter development. This entry names the SF 37: equipment and mission claims from a JA or AJ variant should not automatically be transferred to it.
Saab · Viggen: three decades in Swedish service ↗Saab historical account, 22 June 2021; SF 37 distinguished from the wider family
Systems & details
Hydraulic handling and SPAK
DeltaWing describes custom hydraulic handling and SPAK control augmentation for its SF-37. Its product also identifies CK37 and autopilot systems. Those features belong to the reconnaissance simulation; AJ37 and JA37 equipment are separate variant references.
Airframe configuration
The represented SF-37 has one jet engine, canards, retractable gear and a reversing system.
In your simulator
Systems, equipment and documentation for each developer’s aircraft.
X-Plane 12DeltaWing Simulations SF-37 Viggen
DeltaWing Simulations · Released
DeltaWing Simulations SF-37 Viggen
DeltaWing Simulations · Released
Manuals & resources
Find your next read
Choose a topic for a short introduction and a link to the original source. Simulator references identify the developer and edition they cover.
Developer documentation
SF-37 Viggen — DeltaWing Simulations referenceSaab SF-37 Viggen
SF-37 product Description and Key Features; hydraulic handling, SPAK, custom computer and autopilot
DeltaWing Simulations · Read the source ↗Read the original documentation from the people who created it. Manuals open on their publisher’s website.
Developer documentation
SF-37 Viggen — DeltaWing Simulations referenceDeltaWing Simulations · SF-37 product Description and Key Features; hydraulic handling, SPAK, custom computer and autopilotManufacturer history
Viggen: three decades in Swedish serviceSaab · Saab historical account, 22 June 2021; SF 37 distinguished from the wider familyBuilt-in force-feedback profiles
Read the documentary basis, editable starting settings and remaining questions for the aircraft you fly. Each explanation refers to the exact profile revision shown.
Catalogue programme-20261011-v3 · 1 profile choice
DeltaWing Simulations SF-37 Viggen
DeltaWing Simulations · Free and Pro · Revision 2 · Inherited starting point
X-Plane 12
The reconnaissance Viggen, with canards, a single jet engine and a thrust-reversing system.
DeltaWing Simulations SF-37 Viggen
The reconnaissance Viggen, with canards, a single jet engine and a thrust-reversing system.
Aircraft and simulator scope
- DeltaWing Simulations SF-37 Viggen · DeltaWing Simulations · X-Plane 12 · Add-on starting point
The simulator model and controls
DeltaWing Simulations SF-37 Viggen is the selected DeltaWing Simulations configuration.
How this profile feels
Spring resistance builds with the selected airspeed response. A separate aerodynamic term adds speed-dependent control load.
Pitch-trim relief is off. Autopilot following is off.
Aircraft and configuration
The SF-37 is the reconnaissance member of Saab's Viggen family. Canards, retractable landing gear, one jet engine and a reversing system form the configuration represented by DeltaWing Simulations.
Hydraulic handling and SPAK
DeltaWing describes custom hydraulic handling and SPAK control augmentation for its SF-37. Its product also identifies CK37 and autopilot systems. Those features belong to the reconnaissance simulation; AJ37 and JA37 equipment are separate variant references.
Airframe configuration
The represented SF-37 has one jet engine, canards, retractable gear and a reversing system.
About the values
Strengths are normalized hardware-feel settings. They set the effect balance; hand force depends on the device and its limits. The IAS reference is a tuning value.
Documentary review and sources
These decisions describe the documentary basis and remaining gaps for this revision. Aircraft documentation and a starting setting describe different kinds of evidence.
Aircraft and variant
InheritedDeltaWing Simulations SF-37 Viggen is the selected DeltaWing Simulations configuration.
Flight controls
InheritedThe reconnaissance Viggen, with canards, a single jet engine and a thrust-reversing system.
Trim
InheritedThe profile uses the trim behaviour configured below. Pitch relief is off, with stored authority 0; roll authority is 0.
Autopilot and stability
InheritedAutopilot following is off; the configured spring and load retain the hardware feel.
Equipment
InheritedThe SF-37 is the reconnaissance member of Saab's Viggen family. Canards, retractable landing gear, one jet engine and a reversing system form the configuration represented by DeltaWing Simulations.
Speeds and limits
InheritedThe indicated-speed references set the profile response scale; they are separate from aircraft operating limits.
Simulator integration
InheritedThe profile targets xplane12. Add-on-specific controls use only the supported references configured by this profile.
Force-feedback settings
InheritedThe settings define the profile’s effect balance. Device output limits affect physical hand force.
Starting settings and their rationale
These configured values are starting estimates. The explanations describe what each setting controls; physical validation appears separately below.
| Setting | Starting value | What it controls and why |
|---|---|---|
| Spring strength | Starting value0.74 | What it controls and whyDeltaWing describes custom hydraulic handling and SPAK control augmentation for its SF-37. The baseline spring is 0.74. Low-speed spring blending is off. |
| Master force gain | Starting value0.85 | What it controls and whyScales overall profile strength while preserving effect balance, subject to device and output limits. |
| Profile force gain | Starting value0.25 | What it controls and whyThe aerodynamic-load gain is 0.25 with an indicated-speed reference of 280 KIAS. The hydraulic-load factor of 0.35 scales that modeled term; it is a selected artificial-feel approximation. |
| Force tuning speed/reference | Starting value280 kt | What it controls and whySets the IAS reference for aerodynamic loading. It is an estimate, not published cruise TAS or a flight limit. |
| Spring response reference speed | Starting value45 kt | What it controls and whySets the IAS where the low-speed blend reaches baseline strength; high-speed stiffening also uses it. |
| Aileron force scale | Starting value0.72 | What it controls and whyRoll and pitch aerodynamic scales are 0.72 and 1, respectively. They set the aerodynamic axis balance. No custom spring-travel curve is enabled. |
| Elevator force scale | Starting value1.0 | What it controls and whyScales pitch aerodynamic loading; pitch spring travel and trim responses are separate settings. |
| Trim feel | Starting valueDisabled | What it controls and whyRetained for compatibility and group membership. Trim relief, rather than this flag, controls centre movement. |
| Trim relief | Starting valueDisabled | What it controls and whyAllows trim relief with supported control law and valid telemetry. Axis authorities set its amount. |
| Autopilot follow | Starting valueDisabled | What it controls and whyAutopilot following is off; the configured spring and load retain the hardware feel. |
| Autopilot neutral hold | Starting valueDisabled | What it controls and whyPermits centering hold during a supported AP state, separate from following a moving target. |
| Output force limit | Starting value0.55 | What it controls and whyCaps directed-force output. Native spring effects and device limits remain separate. |
All 44 starting settings and their rationale
The settings define the profile’s effect balance. Device output limits affect physical hand force.
| Setting | Starting value | What it controls and why |
|---|---|---|
| Spring strength | Starting value0.74 | What it controls and whyDeltaWing describes custom hydraulic handling and SPAK control augmentation for its SF-37. The baseline spring is 0.74. Low-speed spring blending is off. |
| Spring deadband | Starting value0.04 | What it controls and whySets travel around the centre before the baseline spring resists. Smaller values engage it sooner. |
| Profile force gain | Starting value0.25 | What it controls and whyThe aerodynamic-load gain is 0.25 with an indicated-speed reference of 280 KIAS. The hydraulic-load factor of 0.35 scales that modeled term; it is a selected artificial-feel approximation. |
| Master force gain | Starting value0.85 | What it controls and whyScales overall profile strength while preserving effect balance, subject to device and output limits. |
| QBlend Enabled | Starting valueDisabled | What it controls and whyAllows baseline spring strength to rise with indicated airspeed where the control law permits it. |
| QSpring Minimum Factor | Starting value0.55 | What it controls and whySets low-speed spring strength as a fraction of baseline when blending is enabled. One keeps full strength. |
| QSpring Start Knots | Starting value10 kt | What it controls and whySets the IAS where the low-speed spring blend starts rising. This is a feel threshold, not a flight limit. |
| Spring response reference speed | Starting value45 kt | What it controls and whySets the IAS where the low-speed blend reaches baseline strength; high-speed stiffening also uses it. |
| Force tuning speed/reference | Starting value280 kt | What it controls and whySets the IAS reference for aerodynamic loading. It is an estimate, not published cruise TAS or a flight limit. |
| Airspeed spring stiffening gain | Starting value0.15 | What it controls and whyThe high-speed spring-stiffening gain is 0.15. It strengthens the permitted spring response above 45 KIAS, with the squared-speed ratio capped at 5. |
| Airspeed spring stiffening limit | Starting value5 | What it controls and whyLimits the squared airspeed ratio used for high-speed spring stiffening; it is not a device-force cap. |
| Aileron force scale | Starting value0.72 | What it controls and whyRoll and pitch aerodynamic scales are 0.72 and 1, respectively. They set the aerodynamic axis balance. No custom spring-travel curve is enabled. |
| Elevator force scale | Starting value1.0 | What it controls and whyScales pitch aerodynamic loading; pitch spring travel and trim responses are separate settings. |
| Output force limit | Starting value0.55 | What it controls and whyCaps directed-force output. Native spring effects and device limits remain separate. |
| Trim feel | Starting valueDisabled | What it controls and whyRetained for compatibility and group membership. Trim relief, rather than this flag, controls centre movement. |
| Trim relief | Starting valueDisabled | What it controls and whyAllows trim relief with supported control law and valid telemetry. Axis authorities set its amount. |
| Elevator Authority | Starting value0 | What it controls and whyThe profile uses the trim behaviour configured below. Pitch relief is off, with stored authority 0; roll authority is 0. |
| Aileron Authority | Starting value0 | What it controls and whyScales supported roll-trim relief and permitted centre movement. Zero removes roll response. |
| Force Trim Enabled | Starting valueDisabled | What it controls and whyEnables local force trim, separate from aircraft-owned trim and add-on integration qualification. |
| GLoad Enabled | Starting valueEnabled | What it controls and whyAllows load-factor changes to modify permitted spring laws. Passive fly-by-wire feel can suppress it. |
| Rate Damping Enabled | Starting valueEnabled | What it controls and whyEnables rate damping with the configured coefficients and control law. |
| Autopilot follow | Starting valueDisabled | What it controls and whyAutopilot following is off; the configured spring and load retain the hardware feel. |
| Autopilot follow authority | Starting value0.1 | What it controls and whySets admitted AP-follow gain, not a percentage of travel. Runtime ownership and input limits still apply. |
| Autopilot neutral hold | Starting valueDisabled | What it controls and whyPermits centering hold during a supported AP state, separate from following a moving target. |
| Autopilot neutral hold strength | Starting value0.6 | What it controls and whySets admitted AP neutral-hold strength; inactive while neutral hold is disabled. |
| Enabled | Starting valueEnabled | What it controls and whyEnables aerodynamic cues; each still needs nonzero strength and its simulator conditions. |
| Gain | Starting value0 | What it controls and whySets stall-buffet strength. Zero removes the cue without changing simulator stalls or warnings. |
| Gain | Starting value0 | What it controls and whySets high-Mach buffet strength; onset and full-strength thresholds are separate. |
| Gain | Starting value0 | What it controls and whySets flap buffet at the configured position and speed gates. Flap movement texture is separate. |
| Maximum flap index | Starting value3 | What it controls and whySets the final flap index for detent normalization. UP plus three detents uses maximum index3. |
| Minimum flap index | Starting value2 | What it controls and whySets the first flap detent that admits buffet; this is a handle index, not degrees. |
| Gain | Starting value0 | What it controls and whySets gear aerodynamic buffet; movement and ground-contact cues are separate. |
| Shaker Enabled | Starting valueDisabled | What it controls and whyPermits shaker at supported warning conditions; the switch does not establish aircraft equipment. |
| Stick shaker amplitude | Starting value0.5 | What it controls and whySets triggered shaker strength; inactive while the shaker feature is disabled. |
| Enabled | Starting valueEnabled | What it controls and whyEnables ground effects; each still needs its own strength and contact or motion telemetry. |
| Gain | Starting value0.4 | What it controls and whySets rolling texture strength, modified by speed, surface and undercarriage configuration. |
| Gain | Starting value0.25 | What it controls and whySets gear-bump texture during ground motion, separate from touchdown impact. |
| Gain | Starting value0.65 | What it controls and whySets landing-impact strength; landing telemetry and response shape determine the pulse. |
| Gain | Starting value0 | What it controls and whySets reverse-thrust vibration with valid reverser and engine conditions. Zero removes the cue. |
| Enabled | Starting valueEnabled | What it controls and whyEnables engine cues with nonzero settings and valid running-engine telemetry. |
| Gain | Starting value0.12 | What it controls and whySets estimated engine vibration using configured telemetry and response, not measured cockpit vibration. |
| Enabled | Starting valueEnabled | What it controls and whyEnables accessory cues with configured strengths and observed accessory movement. |
| Gain | Starting value0 | What it controls and whySets texture from observed flap movement; a command without movement does not establish the cue. |
| Gain | Starting value0.02 | What it controls and whySets texture from observed gear movement, separate from aerodynamic and touchdown effects. |
Limits and open questions
- This is SF37 reconnaissance variant, not AJ37/JA37. Full control manual remains an evidence gap. Custom CK37/SPAK/AP state is unqualified. Nominal profile does not claim full fidelity.
- Nominal force gains, damping and speed references are estimates. Physical and installed-aircraft acceptance deferred.
- No custom AP following, control-law switching or unqualified failure effect.
Physical validation
No physical force validation is recorded in this public catalogue for this revision. Documentary review and software checks do not establish how a particular device feels.
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