Does anyone have a listing of what all the ?TTX reporting marks mean? Would be nice if there is a short easy to read list out there
It has been covered a few times in various magazine articles but I haven't looked for an online source. It's also fluid and has changed over time.
While specific for the F89 flats, here's something I wrote a while ago that's pretty applicable to all 89' TOFC flats:
https://www.therailwire.net/forum/index.php?topic=40536.msg502009#msg502009The overall fleet for double stacks (DTTX), autoracks (ETTX, TTGX etc), spines (TTAX, NTTX, TTRX), 60' flats (HTTX, MTTX, OTTX) isn't too much larger or as complicated.