Overlay question

[xmit]

I've never used any AFCAD overlays but with the increasing amount of AI traffic I'm getting more and more "go around" from the ATC. I was thinking of using overlays and my busiest airports to eleviate the problem with too many flights attempting to land. I've read the AFCAD readme and have a good idea how an overlay works but one question I have is can a base & overlay airport use the same runway for takeoff?

[emh8]

Sorry it took so long for someone to respond!

To answer your question:

[xmit]

I was afraid of that, so that leaves-out all airports with less than four seperate runways.......Bummer........

[emh8]

No..........not really.

You need at least two runways to do an effective overlay.  It helps if the runways are positioned so that traffic can be easily divided into two sectors at the airport.  It also helps if the runways are aligned so that incoming and outgoing traffic doesn't conflict with traffic from the other layer.

Perfect example would be Minneapolis St. Paul Int'l (KMSP.)  You have two parallel runways located on opposite sides of the terminal, 12R-30L and 12L-30R.  Using the overlay technique, you can split the traffic half-and-half between the two runways.  But since each runway will be active for landing and takeoff, THEY WILL BE BUSY!  To be honest, this would simulate real world traffic at KMSP.

Good luck

[xmit]

That's funny, I was thinking of MSP to do my first overlay.......I've added quite a few NW flights and MSP has gotten quite busy. D'oh!....I never thought of having flights arrive and depart from the same RWY. I figured only smaller airports would normally do that. I like to have the ground traffic flow in one direction to help eleviate traffic jams..........

[emh8]

If you are working with an airport that has enough traffic to warrant an overlay, such as KMSP, you'll want to make the runways active for both landings and takeoffs.  

Designating one runway for takeoffs and the other for landings would not only reduce the airport's capacity to handle traffic, it would also defeat the purpose of using an overlay.

As far as ground traffic is concerned, you'll find that if AI is given enough route options for taxiing, the traffic in each layer should flow nicely (in somewhat of a circular fashion.)  In other words, you might want to add an extra taxiway on the ramp in the vicinity of the gates.

Good luck