by Octal450 » Sun Oct 16, 2016 8:05 pm
The controls only move alot when I took over when the gears touch down.
The yoke moved alot because my joystick was not calibrated properly, and is slightly damaged.
It basically works like this:
50ft most G/S stops working good, so at that alt gear-agl-ft, I use a special V/S controller (separate from normal V/S) which takes the command from an internal prop, that is not accessible to the pilot.
It is set to -500, and the plane maintains that through out the align phase.
On 50ft, the target touchdown rate is -150fpm, the V/S controller has been setup to have a slow steady correcting curve, which happens when the autothrottle (or in case of the A340, the pilot) retards the throttle to idle. If the throttle is left in, the flare happens around 10-5ft due to I don't know. But it works.
Notice how the annunciator changed: THRUST changed to RETARD when the A/THR goes to IDLE, and G/S changes to FLARE when the V/S curve starts. I have improved it to make the landing smoother, now it goes from G/S to LAND first, so Land mode is engaged first, and holds the V/S longer, to keep the aircraft more stable for the pitch mode, and then to FLARE when the custom V/S takes over. I also made the A/THR wait before disengaging until the gears touch down, so that a pilot input (or joystick issue) won't break autoland.
As for the roll, it doesn't work with crosswinds yet. I only touched Pitch and Thrust modes. I am currently working on a system that will at 50ft, level the wings, and use the rudder to stay on LOC. Right now it just follows the LOC down with ailerons.
I waited to add in the rudder system because it is tied to the rollout phase, which is separate, and not finished yet. it's still a WIP.
Because it's designed to work on many aircrafts, I didn't set a pitch directly, since it's different for different aircraft, landing weights, conditions, etc. So I use a target touchdown V/S.
Josh
Last edited by
Octal450 on Thu Feb 15, 2024 8:41 am, edited 1 time in total.
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