These "collector cards" have been around for about 3 months. There are a total of 11 in the entire series and consist of the aircraft used on mainline Delta. I am not aware of a similar series for any of Delta's regional partners, such as Comair, Antic Coast or ASA.

Card # 1 is a Limited Edition of the MD-90, Card # 2 is MD-88, Card # 8 is a 767-300, and Card # 10 is 777. (I don't know the rest of the card # from memory & I am at work). The others include the various versions of 737,757,& 767. You can find the card # on the back of each card.

Some pilots carry the cards with them for the aircraft that they are flying. Others don't want to be bothered. If you ask the FA or the pilot when you board, they will usually give you one.

I understand that they recently also started handing out "passports" for infants in arms since they don't get their own boarding pass. I have not seen these yet.

Have fun collecting!!!