Autopilote working

[Simon1279]

You need the latest version of DCS World 2.5 open beta for it to be working, DCS World 1.5.8 it's discontinued

[GoosemanF7]

ok, thanks.

Are there versions on Steam other than 1.5.8 or open beat 2.5?

2.0 or somehting like that?

[Eldur]

How good is the AV8B's autopilot IRL?

 

I suppose it's better still than what we have here which seems to be WIP.

 

2.16.2 Automatic Flight Control

The two AFC mode selection controls are the AFC and ALT HOLD solenoid held switches. All three SAS switches must be engaged in order to engage the AFC mode selection switches. Also, an interlock with the weight-on-wheels switch on the main gear inhibits engagement of the AFC mode switches on the ground and disengages the switches upon main gear touchdown on landings.

 

The AFC switch has three positions which provide the following functions:

AFC – Solenoid held position. Engages the AFC mode.

OFF – AFC mode is off.

RESET – Momentary position. SAAHS reset.

The ALT HOLD switch has two positions which provide the following functions:

ALT HOLD – Solenoid held position. Engages altitude hold option of AFC mode.

OFF – Altitude hold is off.

The AFC switch must be engaged with the INS switch in NAV or IFA in order to engage the ALT HOLD switch. The AFC mode may be disengaged by turning the AFC switch off. Disengaging the AFC switch also causes the ALT HOLD switch to return to the OFF position if it is engaged. Disengaging any of the three SAS switches will disengage the AFC mode. The AFC and ALT HOLD switches will return to the off position if they are engaged. Pressing the paddle switch also disengages the AFC and ALT HOLD switches if they are engaged. Both switches will remain in the off position when the paddle switch is released. The technique of “clicking” the paddle switch may be used to revert from the AFC mode to the SAS mode. Attitude references are to the aircraft waterline.

2.16.2.1 AFC Mode - AFC Switch Only Engaged

When the AFC switch is engaged and the ALT HOLD switch is in the off position, the AFC mode provides pitch attitude hold, roll attitude hold and heading hold. At airspeeds above 50 knots, the AFC will capture and hold pitch attitudes in the ±30° range and roll attitudes within ±60° which are outside of the ±5° range about wings level. Heading hold is provided inside the ±5° roll attitude range for airspeeds above 140 knots if gear and flaps are up or above 0.3 Mach if the gear is down or if STOL flaps are selected (but not both). Heading hold is inhibited at all airspeeds if both the gear is down and STOL flaps are selected. With heading hold inhibited, roll attitudes within ±5° are rolled to wings level. Neither pitch nor roll attitude capture will occur for attitudes which exceed one or both of the ±30° pitch attitude or the ±60° roll attitude ranges. The AFC switch will remain engaged, however, the pilot must control the aircraft in both pitch and roll as in the SAS mode until the attitudes are within both limits. No cockpit indication is given to the pilot when he has maneuvered the aircraft outside the attitude capture limits. With the AFC engaged, mild stick vibration or chatter in pitch may occur during landing approach due to abrupt movement of the forward reaction control valve caused by flight control computer noise. This is normal and should be disregarded.

 

At airspeeds below 50 knots, the roll attitude range is restricted to ±20° and the roll to wings level action extends to the full ±20° range. The pitch attitude capture and hold action is restricted to the +3° to +12° range. Pitch attitudes outside this range but within -15° to +20° will be driven to the nearest of the +3° to +12° range boundaries. The AFC switch will disengage and reversion to the SAS mode will occur if either the ±20° roll attitude range or the -15° to +20° pitch attitude range is exceeded. If the true angle of attack exceeds +15° with the airspeed greater than 60 knots, the AFC mode will be disengaged and reversion to the SAS mode will occur.

 

Automatic pitch and roll trim are provided the AFC mode. The automatic trim tracks the aircraft pitch and rollchanges to keep the series servo actuators close to their neutral positions an effort to minimize disengage transients. On aircraft with departure resistance, the lateral stick to aileron interconnect may prevent the roll auto trim from keeping the aileron series servos near the center of the ±6° range. The automatic trim rates correspond to approximately 0.25° per second stabilator and aileron surface rates and cause the control stick to move in the direction the trim change.

 

2.16.2.2 AFC Mode - AFC and ALT HOLD Switches Engaged

The ALT HOLD switch permits selection of altitude hold in place pitch attitude hold in the AFC mode. The AFC switch must be engaged in order for the ALT HOLD switch to be engaged. In addition, the airspeed must be greater than 160 knots and the climb or descent rate must be less than 2,000 feet per minute for the ALT HOLD switch to be engaged. Altitude hold may be manually disengaged by “clicking” the pitch manual trim button as well as by turning the panel switch off. The operation of the roll attitude hold, heading hold and automatic pitch and roll trim is identical that with the AFC switch only engaged. If either the pitch attitude limits of ±30° or the roll attitude limits of ±60° are exceeded, the ALT HOLD switch will be disengaged and reversion to the AFC mode without altitude hold will occur. The ALT HOLD and AFC switches will also disengage if the displayed AOA exceeds +16° ±1°.

 

Altitude hold is also monitored by logic which will disengage the ALT HOLD switch and revert to AFC without altitude hold if any of the following events occur:

1. The altitude hold does not lock on to an altitude reference within ±250 feet following manual engagement of the trim switch or following interruption of altitude hold by longitudinal stick forces exceeding 1 pound. An altitude reference is established when the altitude rate is driven below 500 feet per minute by the altitude hold synchronization.

2. An excursion in altitude which differs by more than ±250 feet from the altitude reference.

3. The altitude changes due to stick or trim inputs by a cumulative total of more than ±250 feet following establishment of an altitude reference.

4. The altitude rate exceeds 2,000 feet per minute or the airspeed falls below 160 knots.

2.16.2.3 Maneuvering Flight In AFC Mode

The AFC mode includes a pitch and roll control stick steering (maneuvering) capability with the AFC switch engaged. The pilot can use the control stick and the manual trim switch to maneuver the aircraft and lock the AFC onto new pitch attitude, roll attitude and heading references without disengaging the AFC switch during the maneuvers. Pilot applied longitudinal and lateral stick forces in excess of approximately 1 pound interrupt the attitude and heading hold functions and inhibit the pitch and roll automatic trim allowing the aircraft to be maneuvered as in the SAS mode. Just as in SAS mode maneuvering, the pilot must trim out any stick forces prior to releasing the stick. This is important because the auto trim capability may have been exceeded when significant trim changes were made as a result of maneuvering.

 

Small attitude changes can be made with stick forces below the 1 pound level by inducing aircraft motion with small stick inputs and “clicking” the manual trim switch. Activating the pitch and roll manual trim switch interrupts the attitude and heading hold functions and automatic trim so that “clicking” the trim switch has the effect of updating the attitude hold references to the current aircraft attitudes. If altitude hold is engaged, changes in the roll attitude can be made in the same manner. “Clicking” the pitch manual trim switch disengages the ALT HOLD switch which provides a convenient method for reverting to pitch attitude hold for making altitude changes. ALT HOLD shall be disengaged whenever any pitch maneuvering is done. The ALT HOLD switch must be turned back on to re-engage altitude hold at the new altitude.

 

Heading changes can be made by banking outside the ±5° roll attitude range to interrupt the heading hold and rolling to wings level on the new heading. Small heading changes of a few degrees can be made without banking by sideslipping the aircraft to the new heading with the rudder pedals, “clicking” the roll manual trim switch to capture the new heading reference, and slowly releasing the rudder pedal input to minimize the heading transient. A tendency to hold a heading in a slight bank is indicative of a steady heading sideslip due to rudder mis-trim. This can be corrected by trimming the rudder.

 

AFC mode interrupts by stick force and manual trim switch inputs operate independently in pitch and roll within the AFC mode attitude limits of ±30° in pitch and ±60° in roll above 50 knots and -15° to +20° in pitch and ±20° in roll below 50 knots. The pilot can maneuver the aircraft in pitch without affecting the roll attitude hold and heading hold functions or maneuver in roll without affecting pitch attitude or altitude hold.

 

During significant aircraft trim changes, such as those produced by engine nozzle rotation and aileron droop, the action of the AFC mode is to hold the aircraft pitch and roll attitudes. The automatic pitch trim adjusts for the longitudinal trim change and the automatic roll trim adjusts for any roll trim changes due to asymmetric effects. If the pilot opts to control the aircraft manually during such trim changes, the attitude hold and automatic trim functions will be inhibited and it will be necessary to retrim the aircraft manually in pitch and roll to smoothly restore the attitude hold functions. Rapid acceleration or deceleration with asymmetric loaded stores may cause aircraft roll rates that exceed the response capability of AFC roll trim. If this happens the pilot should take control of the aircraft until the acceleration or deceleration is over, manually trim the aircraft and then reengage AFC. On aircraft with departure resistance, at the AOA where departure resistance becomes effective, a slow transition between AFC and departure resistance occurs.

 

Especially the part saying that even the stick can be used to control while the AFC is running to make corrections is interesting - this doesn't work in our module yet and would make things a lot easier.

[noisy_lightning]

I suppose it's better still than what we have here which seems to be WIP.

 

 

 

Especially the part saying that even the stick can be used to control while the AFC is running to make corrections is interesting - this doesn't work in our module yet and would make things a lot easier.

Using the trim hat does work when AFC is enabled as I use that quite a bit when searching for targets to control my orbit. But you are correct that moving the stick does not work yet.

[Raz_Specter]

it would be great if we could have some audible tones to signify that either had been engadged. Bit like the A10

[Eldur]

Yes, trimming with AFC on works pretty well at least in cruise flight. But it's totally oversensitive in pitch. For stabilizing a hover or trying to stay on a tanker though it's absolutely useless. Especially in a hover it's impossible to translate. Trim hat left or right, nothing happens, but then out of a sudden you get a 45° insta-bank that is utterly hard to recover. And thanks to the overly high sensitivity of the pitch component, it's practically impossible to null out the forward/back speed. I take it as WIP, patience is the key. I'm sure the devs will get this right eventually

 

At the moment it's a great help already for cruising and when trying to find and lock up things on the DMT

[Sarge55]

I don't think you are suppose to use AFC in Hover or AAR.

[davidp57]

Well I use it in the first phase of an AAR, while I position my plane behind the tanker for pre-contact. It sets my trim automatically for the tanker speed and that spares me a few seconds...