Special Controls

Special Controls is a fun part of Plane Maker that can be used to add a variety of unrelated technologies and gimmicks to your aircraft.

to do... can we make the article content wrap around the table of contents, so the TOC is on the left, and the article begins immediately upper-right?

Jet assisted take-off

Jet assisted take-off or JATO is actually a strange military term for single-use rockets that are fired (typically) on take-off to reduce the ground run. These are usually solid-propellant rockets, but historically liquid-fueled rockets have been used, too.

The data fields are:

• For geometry JATO long arm, JATO vert(ical) arm, JATO angle
• JATO thrust
• JATO duration
• JATO specific weight

Note on the geometry: You should make sure that the thrust line of the JATO unit runs approximately through the centre-of-gravity of your aircraft! Else lighting and burn-out of the JATO rocket will introduce a trim change - the more powerful the rocket, the worse the trim change.

Note on the weight: Duration is in seconds, specific weight is in pounds per pound-force per hour. If you know that a JATO unit delivers 4400 lb(f) (=pound-force) of thrust and burns for 6 seconds, and that its weight is 73.3 lbs, you can calculate the specific weight as follows:

• 73.3 lbs / (4400 lb(f) * 6 s/3600) = 10.0 lbs/(lb(f)*s) - after all, there are 3600 seconds in an hour
• Alternative method: Enter something remotely sensible for specific weight, then check the resulting JATO weight as indicated on the Weight and Balance sheet, then go back to Special Controls and make a better guess ...

Don't forget to add a JATO button on the Panel, too!

Equipment Options

Tick any checkbox here to add a certain type of equipment to the aircraft.

Auto speedbrake on touchdown

This enables the aircraft to deploy the aerodynamic brakes automatically on landing gear ground contact, if the automatic deployment is armed by putting the Speed Brake handle in the full-up 'ARMED' position. The Speed Brake handle (han_sbrake2) has to be added on the Panel in order to use this feature.

Auto wheelbrake on touchdown

This enables the aircraft to use the wheelbrakes automatically to achieve certain hard-coded decelerations, depending on the position of the Auto Brake switch that has to be added on the Panel in order to use this feature.

The Auto Brake switch has the following positions:

• RTO: Rejected Take-Off
• Off: Nothing happens
• 1: deceleration -0,124 G
• 2: deceleration -0,155 G
• 3: deceleration -0,224 G
• Max: deceleration -0,37 G or -0,43 G

Rejected Take-Off: Autobrakes armed to RTO will engage the wheelbrakes when a significant drop of thrust occurs. On a rejected take-off, that drop of thrust would of course be caused by the pilot pulling back the throttles!

Auto reverse on touchdown

This enables the aircraft to employ reverse thrust automatically on touch-down. To use auto-reverse in the simulation, it has to be enabled using the Auto Reverse selector on the Panel. There are also three required settings in PlaneMaker:

1. The Auto-Reverse Switch button must be added to the Panel.
2. The max reverse throttle setting under Engine Specs must be set to a value other than 0
3. The all engines reverse-thrust available checkbox under Special Equipment must be selected.

Gear extend protect

This will prevent the aircraft from extending the landing gear at speeds exceeding the Maximum Landing Gear Extended Speed (V_LE) defined on the Viewpoint screen.

Flap extend protect

This will cause the aircraft to prevent flap deployment at speeds exceeding the maximum defined on the Viewpoint screen.

Flap Retract Protect

This will cause the aircraft to retract flaps if the maximum speed defined on the Viewpoint screen is exceeded.

Auto-lock tailwheel elevator fully aft

This simulates automatic tail wheel locking, as for example used by the North American P-51 Mustang or the Dornier Do 217. It allows locking the tail wheel to the center if the stick is aft of the center position.

Note: In X-Plane 8.xx and early 9.xx versions, the tail wheel was locked only with the stick fully aft. The current version X-Plane 9.67 has been fixed and works as desired.

Auto slats near stall

This causes the slats to be deployed at a certain angle of attack. The angle of attack at which the slats are deployed depends on the value entered as stall warning angle on the Viewpoint screen. If the stall warning angle is too close to the actual stall angle, there will be no benefit from auto slats, so a certain margin between warning and actual stall is required.

If a slat extension greater than 0.0 is set in the Control Geometry menu, this overrides auto slat deployment when the flaps are deployed. (ToDo: Find out if it also overrides when the flaps are not deployed.)

To have freely operating slats with the flaps deployed, the slat figure on the Control Geometry screen has to be set to 0.0. This configuration was for example used by the Messerschmitt Me 262 jet fighter.

To have the slats locked open with the flaps deployed, the slat figure on the Control Geometry screen has to be set to a figure greater than 0.0. This configuration was for example used by the Savoia-Marchetti S.M.79 trimotor bomber.

Auto flaps near stall

This causes the flaps to be deployed at a certain angle of attack. The angle of attack at which the flaps are deployed depends on the value entered as stall warning angle on the Viewpoint screen. If the stall warning angle is too close to the actual stall angle, there will be no benefit from auto flaps, so a certain margin between warning and actual stall is required.

Auto-trim pitch loads

This is used for gradually and automatically loading helicopter pitch trim upon application of joystick pitch such as on the Comanche helicopter.  It is not for fixed-wing aircraft.72.49.207.62 09:12, November 29, 2020 (UTC)Reticuli

Anti-ice equipped

(ToDo: Find out if this is necessary at all if the appropriate switches are on the panel.)

Arresting gear equipped

This makes the aircraft capable of performing arrested landings on an aircraft carrier. To activate the arresting gear, push the arrestor gear button that has to be added on the Panel to make this work.

Note: There is no visible indication of the arrestor gear being deployed. To create a visible tailhook, you'd have to use Objects. Simulating the hook with extra landing gear legs or Misc Bodies is not recommended as it changes the geometry of the landing gear and does not represent the tailhook status accurately anyway.

See also: Carrier Operations

Gear warning horn equipped

This will sound a warning signal if the throttle is retracted beyond a certain point when the gear is not extended. (ToDo: Does it really work that way in X-Plane, or does it require a minimum altitude or flap deployment as well?)

Parachute

This will equip the aircraft with a parachute. The most common use is as a brake chute for landing (sometimes referred to as a drogue parachute), but some plane builders have also used it to simulate a Ballistic Recovery System or a dive brake. The parachute activation requires a button on the Panel.

Note: In X-Plane, the parachute can be recovered and re-used in flight. Brake chutes usually can be used only once and at the end of the landing run are separated from the aircraft and recovered by the ground crew. However, some aircraft had chutes capable of in-flight recovery, for example the Dornier Do 217 which used a parachute as dive brake.

The data fields for the parachute are:

• Parachute longitudinal arm
• Parachute vertical arm
• Parachute front area

Tip: When including a parachute for use as a landing brake chute, be sure that the longitudinal arm is at a location greater than (further aft of) the aircraft's center of gravity (CG), and preferably near or below the vertical CG.

Special Control Deflections

This section serves to generate control deflections beyond the traditional control of "stick lateral = aileron, stick longitudinal = elevator, rudder pushed = rudder".

The tickbox "additive control deflections can go beyond basic deflections" refers to the basic deflections as defined in the Control Geometry menu.

Differential elevator & stabilator with roll

Here the maximum deflection for tail surfaces in response to aileron input is entered. This feature is also sometimes called "taileron" and used by many modern jet fighters. Some jet fighters like the English Electric Lightning use taileron in combination with the "aileron cut-out" feature described below.

Differential elevator & stabilator with yaw

Here the maximum deflection for tail surfaces in response to rudder input is entered. This feature is required for V-tails to work.

Ailerons with pitch

This deflects the ailerons symmetrically (like flaps) when the stick is pulled back to increase the camber of the wing and thus generate more lift. While Plane Maker states Austin Meyer is not aware of any aircraft to use this, the Hirth Acrostar aerobatic aircraft actually used this for symmetric flight behaviour under positive and negative G's.

Two data fields are provided, one for each set of ailerons as defined in Control Geometry.

Ailerons with flaps

This lowers the ailerons when the flaps are deployed so that they serve as auxiliary flaps. This feature is for example used by the Messerschmitt Me 109E and also on the Bell XV-15, both of which lower the ailerons by about half the flap deflection angle for landings.

Two data fields are provided, one for each set of ailerons as defined in Control Geometry.

Rudder with aileron

This feature deflects the rudder when the ailerons are deflected in an attempt to maintain coordinated flight automatically. This feature was for example used by the first Wright Flyer and was part of the original patents of the Wright brothers.

Cutout speeds

To switch off certain sets of ailerons or roll spoilers above a certain speed, enter the cutout speed here. This feature is used for example by the English Electric Lightning to switch off aileron control at high speeds in order to avoid overstressing the thing wing - roll control is then achieved by taileron alone.

Differential Thrust for Maneuvering

This section serves to configure the use of engine thrust for flight control.

Thrust vector with pitch/roll/yaw input

These three data fields describe how far the thrust vector of the engines is tilted when the respective control is fully deflected.

The tick box "full on at 0°" makes thrust vectoring fully active when the thrust vector is aligned with the aircraft design axis.

The tick box "full on at 90°" makes thrust vectoring fully active when the thrust vector is perpedicular to the aircraft design axis.

The two tick boxes can be used to make thrust vectoring effective either in forward flight or in VTOL mode, or under both circumstances. (ToDo: Someone who has more experience with VTOLs should check this :-)

Note: Typically, roll control by thrust vectoring requires at least two engines, with the one on the downgoing side tilting its thrust axis upwards and the other one tilting it downwards.

Throttle with pitch/roll/yaw input

These three fields describe by how much thrust is modulated to achieve flight control. This is typcially used by VTOLs. An example for the use differential thrust is the Dornier Do 31 VTOL transport, which uses its wing-pod lift engines to achieve roll control while in hover.

Wing tilt for maneuverering

This section describes how far the wing can be tilted for achieve control. Ultralight trikes often use wing tilt for control.

There are two data fields, one for lateral control and one for longitudinal control.

Auto-deflections

This section describes automatic control deflections that are usually used to trim the aircraft on a configuration change.

The field "stabilizer with flaps" typically serves to counteract the trim change induced by lowering or raising the flaps. An example for this feature is the Messerschmitt Bf 110.

Note: Only the default horizontal stabilizer will move through the angle specified. If other wings are used to emulate the horizontal stabilizer, this feature will not work.

The field "rudder with engine failure" serves to counteract the trim change induced by the loss of an engine that is laterally off the centreline of the aircraft.

Dynamic flap actuation

This section serves to re-use the flaps for manoevering purposes.

The two data fields "Flaps with pitch input" are used to deflect the the two sets of flaps when the stick is pulled back to increase the camber of the wing and thus generate more lift.

The two data fields Flaps with roll input" are used to deflect the the two sets of flaps asymmetrically in response to aileron input to roll the plane.

Each tick box "hi-dep" restricts the use of flaps of the respective feature to control inputs above 50% of the maximum, letting the flaps cut in only at high deflections.

Note: Dynamic flap actuation is not subject to damage even if the flaps are deflected at speeds exceeding the limit set on the Viewpoint screen. However, if the flaps are damaged by exceeding that speed while they are used as standard flaps, dynamic flap actuation can make the aircraft uncontrollable on landing. It's recommended that you set a very high speed limit for flap damage to avoid this effect.