Contact Air From Germany, joined Apr 2001, 1154 posts, RR: 14 Reply 1, posted (11 years 11 months 1 week 4 days 12 hours ago) and read 1317 times:
That's an interesting question. I have asked that myself already, too. In fact, on the MD-88, you find very similar registrations: for example, there is as well N912DE AND N912DL.
You also find this at other US-carriers: For example:
- Northwest: NW, US, NB, etc.
- US Airways: US, UW, AU
And these are all planes that were originally delivered to the certain airline, no second-hand planes or planes that came to the airlines after mergers or acquisitions.
OPNLguy From , joined Dec 1969, posts, RR: Reply 2, posted (11 years 11 months 1 week 4 days 11 hours ago) and read 1288 times:
As mentioned, some numbers have their roots in the former operator(s) of the aircraft.
That aside, the other main reason aircraft have different letters other than those expected is that the N-numner is already taken. For example, a desired N245DA might already have been assigned to another aircraft (GA or corporate, most likely), so they go for something similar line N245DX or whatever they can get. Doing so allows the airline to keep the N-number consistent with the aircraft's company "fleet" number (if that's what they want) used for various purposes.