Hey Ryan, I always appreciate your insights. In this particular case the issue was that the runway and approach BATC was offering / requiring was not even listed in the Citation, and I was just about to start my descent. There was just no way to force BATC to approve the runway / approach I had, and I had no way to select the option it was giving me. Even waiting to specify the arrival details and letting ATC provide them proved problematic. I really like BATC but this stuff just blows it for me. 

The same problem happened on a flight from KDEN to KDFW. I get 30 miles to descent and find out i cannot select the runway BATC was forcing me to take, and they won’t allow my runway change. Pilot2ATC has an option to force ATC to use the flight plan and I can now see why that is important. 

Thanks again for your help!

8 hours ago, regis9 said:

I actually find it odd that BATC would use the 6 and 7 runways with winds 070/5.  LAX normally prefers the 24/25s…is a five knot tail wind enough to overrule that preference?  BATC as I understand it is programmed for real world ops, wind limitations, preferred runways etc at many airports.

Having said that, I’ve certainly had times where the assigned runways don’t make sense either for the weather or real world ops.  In those cases I shut it down, take off, then reconnect in the air.

I’ve had some experiences at YYZ where the crosswind runways (15/33s) would be active when the crosswind was not sufficient for them to be running, then the cross wind runways not active when the crosswind was too strong for the main runways to be active.  I recall seeing a YYZ update recently so perhaps that has been fixed.

What weather source does BATC use?  I find the ATIS often doesn’t match up with the weather conditions I see in the sim using live weather - mostly minor things like the wind being a bit different speed, altimeter not the same etc so it’s often close, but not quite right.

I think that you more or less answered your own question. However, I own multiple 3rd party ATC add-ons, but unfortunately I can only guess at what happened to you at LAX. The add-ons like BATC have runway ops for airports with multiple runways and usually the low (or calm) wind runway(s) is specified. Low wind is usually considered to be 0 to 5 Kts. The problem is that this creates a discontinuity at 5 to 6 Kts where the active runway could hypothetically switch. In the real world, the airport's chief AT controller doesn't keep changing the active runways every time the wind speed goes from 5 to 6 kts. Generally, real world runway shifts are kept to a minimum during a given day and are only mandated after frontal passages that cause drastic changes in wind speed and direction.

Another issue is the timeliness of the weather data and how often it is updated in the ATC app. Each ATC app (and the sim for that matter) uses a slightly different approach to obtaining and updating weather data.

Also, I noticed you mentioned crosswind runway use. This is commonly only important for GA and other light aircraft, at least for wind and wind gust velocities normally experienced at most real world airports. This doesn't mean that crosswind runways are never used. They can also used by mid-sized commercial jets when the crosswind or tailwind component exceeds the design spec for that aircraft model. A crosswind runway might also be used to ease separation bottlenecks. It also could be used if its taxiway locations provide a shorter path to either the stand or the FBO apron. In any case, if you are piloting either a B737 or an A321 in the sim, the active runway will be either the calm wind runway or the non-crosswind wind runway best aligned with prevailing wind direction. At least it should be.

One last real world consideration is for night ops, often 2300 ± to 0500 ±. Noise abatement procedures may dictate that certain runways should not be used at night, since the flight path take the low flying aircraft over heavily.populated areas. Takeoffs are more critical because they generate more noise than landings.

15 hours ago, RobJC said:

BATC tells me to use 6R and also tells me that I need to transition via KOUFAX, so my entire flight plan is hosed

I fire up BATC as soon as the flight has started and open the frequencies page to see which departure runway BATC is going to use. Or I listen to ATIS before programming the route.

I think BATC differs most from the OFP with very light or variable winds which I guess happens in real life...

6 hours ago, jabloomf1230 said:

Also, I noticed you mentioned crosswind runway use. This is commonly only important for GA and other light aircraft, at least for wind and wind gust velocities normally experienced at most real world airports. This doesn't mean that crosswind runways are never used. They can also used by mid-sized commercial jets when the crosswind or tailwind component exceeds the design spec for that aircraft model.

That’s not the case I was referring to at YYZ.  Primary runways are 23/24s, these are used whenever possible up to cross wind limits generally.

The crosswind runways (15/33) are only used if the wind conditions absolutely require it due to crosswinds being too high to use the 23/24s.

19 hours ago, Tuskin38 said:

SI only uses Simbrief runways every time if you turn on the option to force them under realism settings.

You're right. I forgot that was an option (that I had turned on, when I used to use SI).

10 hours ago, flyingscampi said:

I fire up BATC as soon as the flight has started and open the frequencies page to see which departure runway BATC is going to use

The first flight after I type this, it changes the runway with the IFR clearance 🙄