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MSFS fully free castering tailwheels...

jcomm

jcomm

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portugal
using the new variables, how would you model an aircraft with no mechanical steering available - totally free castoring wheel ?

max_speed_full_steering = x ; Defines the speed under which the full angle of steering is available (in feet/second).
max_speed_decreasing_steering = y ; Defines the speed above which the angle of steering stops decreasing (in feet/second).
min_available_steering_angle_pct = z ; Defines the percentage of steering which will always be available even above max_speed_decreasing_steering (in percent over 100).
max_speed_full_steering_castering = w ; Defines the speed under which the full angle of steering is available for free castering wheels (in feet/second).
max_speed_decreasing_steering_castering = r ; Defines the speed above which the angle of steering stops decreasing for free castering wheels (in feet/second).
min_castering_angle = 0.04236 ; Defines the minimum angle a free castering wheel can take (in radians).
max_castering_angle = 3.14159265358979 ; Defines the maximum angle a free castering wheel can take (in radians).

plus the required , which I set to 180 degrees...

point.0 = 1, -10.5, 0, -2.08, 750, 0, 0.523, 180.0, 0.114, 2, 0.7, 0, 0, 0, 165, 165, 2

I interpret the variables in such a way that those not mentioning "castering" should refer only to the cases where some sort of mechanical interconnection exists between the tailwheel and the rudder, while those that have "castering" in their name refer to "free castering" tailwheels ?

So, if I want to model an aircraft where no links exist between the talwheel and the rudder controls I would make:

x = 0 ; because I don't want to be able to steer directly using a rudder control interlink
y = 0 ; or a very high value, way above takeoff speed ?
z = 0.0 ; because I don't want any steering available whatsoever ( mehanically )
w = value_of[takeoff speed + 10] ; What do you think ?]
r = 0 ; I want to have full castering steering capabilities right from brakeoff

min and max catering angles can be left that way, and in point.0 I set the 8th field to 280, to allow the wheel to swevel 140 º either side ( should I set it to 180 º instead ? )

Thx for any sugestions / comments ...
 
Last edited:
Well, :-/

can't really figure out how to properly model the free castering tailwheel in MFS ...

Have tried a few combinations of the above with no success, unless it's also something with the visuals that doesn't correctly portray
the tailwheel freely castering.

Any ideas really welcomed !
 
I replied on this via Avsim. I haven't tried any value other than the standard "180". Maybe a larger or smaller angle will work. too. When I have time to tweak a tail dragger I'll give it a go.
 
Tailwheel steering has a complex set of effects.
First, a tailwheel airplane is unstable in yaw when taxying and a lot of the effort by the pilot involves trying to follow the centreline of the taxiway.
You steer the airplane by using differential wheel brakes or the rudder effect of propwash. The rudder effect is zero if there is no prop induced airflow on it.
Differential wheel brakes start a yaw which will either dissipate under the influence of a castoring tailwheel or wheel brakes in the opposite direction.
When braking with a tailwheel airplane the quickest way to stop it to tip it over so the prop strikes the ground, not recommended but it is an ever present danger and limits brake effectiveness.
Wind direction has a huge effect and may prevent turning or make it too strong with turn overshoots.
Surface hardness is important in really old airplanes that have a tail skid rather than a wheel. OK on grass but ineffective on a hard surface.
It is unlikely if not impossible that the tailwheel will castor as much as 90 degrees unless the airplane is being blown around by the wind.
Once you have got to the end of the runway and are pointing in the right direction, life becomes easy because propwash will keep you straight as long as you apply the right amount of rudder to counteract the yaw from the propwash rotation on the fin.
When landing you go through the same issues plus the worst bit which is taxying down wind which can involve a series of difficult attempts to get closer to the parking.
I would say Good Luck to anyone trying to make a science out of it.
Roy
 
Did anyone end up figuring this out? I'm also trying to make a tail-dragger but it seems that MSFS does not support free-castoring wheels at all. Also setting the 8th contact point field to anything beyond 90 is considered invalid, so setting it to 180 will set it to either 18.0 or 0.

Even the default aircraft use a 'fake' free-castor that is linked to the rudder for steering. It seems impossible to 'unlink' the rudder from the steering to make a true castor.

Any information regarding how to actually get one setup would be great (or even an example of an aircraft for the sim that actually has free-castoring wheels - so far I've yet to find any)
 
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