AFCAD Request

[Guest kimgesch]

Does anyone have an AFCAD for KDTW that will work with the scenery by Mike Manger (kdtw_v2.zip)? Thanks

[Mike... 7]

What's wrong with the one in the package?

[Guest kimgesch]

There's nothing wrong with it, my AI aircraft take some pretty crazy routes to get to the runways. I wasn't sure if someone had done one that had a different traffic flow. Or a suggestion how to modify the taxi path.

[Mike... 7]

Well, there doesn't appear to be anything wrong with the Afcad. Can you give a specific example/screenshot? Are you perhaps talking about departing aircraft taxiing to 3L. Some of them will take the "long" way.Also, make sure you only have one Afcad active for KDTW.

[Guest kimgesch]

I don't have a screen shot, it's mainly as you described, some a/c take a long way to 3L. Plus there seems to be a bottleneck exiting from the north end of the midfield terminal. I also get a bunch of NW AI aircraft pushing at the same time and then they taxi through other pushed aircraft. That may be an AI issue though...

[Mike... 7]

Sounds like limitations of FS and not of the Afcad, I'm afraid. Once you start FS, you should give FS some time to settle down. I always give FS like 5, 10 or even 15 minutes to get the traffic going. Then when you start to taxi yourself, the traffic around you is pretty "normal".

[Guest kimgesch]

Thanks, how does FS assign which runway is used? Is it by whichever is closest to the aircraft?Is this your scenery?

[RFields5421 1]

The takeoff runway assignment can be quite complex based on aircraft empty weight and engine type as they relate to runway length and surface type requriments - in addition to location.But for an airport like KDTW where the runways are almost all plenty long enought of the heaviest jets - the deciding factor is almost always which open for takeoff runway whose CENTER POINT is closest to the aircraft when the aircraft ask for taxi clearance.In some cases this will be different than the runway which would be assigned if the aircraft asked for taxi instructions before pushback.In a couple cases I've seen large AI aircraft and small AI aircraft be assigned to different takeoff runways when pushed back from the same parking spot. Because larger aircraft push back farther.One exception to the distance rule is the extended runway centerline. For a certain distance and angle from the runway centerline - all AI aircraft which ask for takeoff clearance will be assigned to that runway.i.e. at KDTW any aircraft parked near the default Gate G11 / G12 & G13 (GA Medium spots) will be assigned to takeoff on Rwy 03L/21Rat KORD any aircraft parked near the default Gate P3 and Parking 2 and Parking 3 GA spots will be assigned to takeoff on Rwy 14L/32R if it is active for takeoffs.

[Mike... 7]

Basically, yes, closest to the runway centerline. (If it's long enough for a particular aircraft.) Detroit is not that bad actually, since you have four parallel runways. Inner runways for take-offs, outer runways for landings. You can active the 9/27's as well, but then it's gonna get messy, especially with 9L/27R. Personally, I only use the parallel ones and it works okay.And no, it's not my scenery.

[Guest kimgesch]

Is a centerline necessary? I thought I read that it wasn't necessary, is this true? and if not, and it's deleted, does it just go by the center of the runway?

[Guest kimgesch]

Are the arrival assignments assigned the same as the departures?

[Mike... 7]

As I understand it, arrivals are assigned based on which runway is closest, but also based on which runway has a heading (or heading + 180 degrees) closest to the heading of the aircraft when the assignment takes place. This is why you can still get arrivals on a runway closed for landings if that runway doesn't have a parallel counterpart opened for landings and if that runway happens to be "in the path" of an aircraft. Of course, the length of a runway is important as well. And I'm sure there's a lot more to it that I don't know about. I'm not half the expert Reggie is. ;-)To keep it simple, in Detroit traffic from the West will land on 4L/22R, traffic from the East will land on 3R/21L.

[RFields5421 1]

The only weight factor I'm aware of for arrival runway assignment which has been identified is 93,000 lbs empty weight. That will put jet aircraft on runways longer than 7,000 feet for landing if available, or the longest available runway if possible. That weight is heavier than a B737 which is why we don't see the effect at airports like KMDW or KSNA.KDTW is pretty much an "Outer Arrivals, Inner Departures" airport - with almost all arrivals on the outer runway pair and almost all departures on the inner runway pair as described above.There is an extended runway centerline effect for arrivals also which could put a few aircraft into the inner runway pair. It would take a very precise departure locations and AI creation locations on the grid for it to work.There is a possible trick with runway length where you could make one of the outer runways shorter than 7,000 feet and that would put the smaller aircraft arriving from that direction on the outer runway and the heavier aircraft on the inner runway next to it. That way you could have three landing runways and one takeoff runways.I'm not familiar with the KDTW traffic enough to be sure if that would benefit or hurt overall traffic flow.

[Mike... 7]

I wonder, my KSFO Afcad is set up as follows. 1L, 1R, 10L, 10R all closed for take-offs and landings. Reciprocal ends opened for both. And all runways are active. Yesterday I arrived from the Northeast in a 777. I had planned to land on 19L, but ATC told me to go to 28R and it didn't give me a choice to request another runway.19L is only 8654 ft. 28R 11861, and 28L 10594. Now perhaps 19L was deemed too short?! (Although I seem to remember landing there before in a 777 as well.) But why couldn't I choose between 28L and 28R?Very odd. AI traffic was using all runways.Same goes for transitions, sometimes your flightplan leads you to/over an entry of a transition, yet, ATC won't allow you to choose that transition.

[RFields5421 1]

Often you have to request a different approach before being able to request a different runway.