The last valid O&D numbers I could get my hands on show DFW-MCI at 680 psgrs per day at an average fare of $208.74 and STL as 700 psgrs per day at an average fare of $215.21.
Let's say, for the sake of argument, that Southwest puts 4 RTs a day in each market and American maintains about 12 RTs in each market - although American splits their flights out to where 8 operate from DFW and 4 operate from Love.
I would estimate that the average fare in the market falls to (129+59)/2 or $94.
The markets will be stimulated to some level of about 2.38 times their current size, 1620 and 1667 psgrs per day respectively.
1215 and 1251 psgrs per day, respectively, will choose to fly from DAL over DFW.
Southwest will capture 65% of the Love Field market, which will give them 789 psgrs per day between DAL & MCI and 813 psgrs per day between DAL & STL.
There are currently 156 psgrs per day flowing from MAF, LBB, and ELP thru DFW and on to MCI or STL.
Let's say this sees a market stimulation (due to price) of 25%....that puts it up to 195 psgrs per day. We'll assume WN gets 40% of that, or 78 psgrs.
So Southwest is looking at boardings of 828 psgrs per day between MCI and DAL and 852 psgrs per day between STL and DAL.
That achieves a Load Factor of 75.5% and 77.7%, which probably means you are looking at them adding a 5th RT in each market pretty quick.
American's Love Field boardings, on the other hand, amount to 425 psgrs per day between DAL & MCI and 438 psgrs per day between DAL & STL. That gives them, assuming they use MD80s, a LF of 37.4% and 38.6% to MCI and STL, respectively, at an average fare of $94.
Let's say AA has a CASM of 13 cents for stage lengths of roughly 500 miles.
Each Kansas City flight will cost them $8510 and each St Louis flight will cost them $10,171
That means each flight to or from Kansas City will lose AA $3517 and each flight to or from STL will lose AA $5025.
The whole thing will not cost AA all that much, really, just an additional $25 Million a year in losses.
By the same token, if you figure WN CASM at 8 cents you have this scenario making them an additional...$24.9 Million a year on the bottom line.
So keep this post in mind about 18 months from now when the DOT figures become available for Q1 of 2006 and see how close I am.