aaronhurd

Does anyone have a comprehensive guide to Delta fare basis codes? I'm looking for more than simply the listing of fare classes at:
http://www.cwsi.net/delta.htm

I did find the following guide to IATA fare bases, which gets me partially there, but it doesn't explain everything that I've seen:
http://www.atpco.net/atpco/download/rbd_iata_res728.pdf




The story behind this question is that I'm trying to figure out why I can't book a certain round trip under some fare bases. ExpertFlyer is showing me the following fares:
(The boldface indicates what I haven't been able to interpret.)

TLXPV74 DL T Round-Trip 312.00(USD) E 12/24/10 12/26/10 SU / 3M 07
TLXSL95 DL T Round-Trip 383.00(USD) E 12/25/10 03/31/11 SU / 1M 14
ULXSL95 DL U Round-Trip 393.00(USD) E 12/25/10 03/31/11 SU / 1M 07

And there is both U and T availability on Delta-coded, Delta-metal flights on those days:

Outbound:
DL () 252 0 DTW
01/10/11 3:50 PM AMS
01/11/11 5:55 AM 333
Daily
87% / 43m J9 D9 S8 I8 Y9 B9 M9 H9 Q9 K9 L9 U9 T9
DL () 9553 0 AMS
01/11/11 9:55 AM DUS
01/11/11 10:50 AM F70
Daily
95% / 10m C9 D9 S8 I8 Y9 B9 M9 H9 Q9 K9 L9 U9 T9

Return:
DL () 9439 0 DUS
01/19/11 6:15 AM AMS
01/19/11 7:15 AM F70
Daily
92% / 31m C9 D9 S9 I9 Y9 B9 M9 H9 Q9 K9 L9 U9 T9
DL () 243 0 AMS
01/19/11 10:50 AM DTW
01/19/11 1:30 PM 333
Daily
90% / 26m J9 D9 S9 I9 Y9 B9 M9 H9 Q9 K9 L9 U9 T9

But I can't book this round trip under any of the above fares.