Neilalp From United States of America, joined Apr 2000, 1034 posts, RR: 1 Reply 1, posted (11 years 3 weeks 5 days 12 hours ago) and read 517 times:
Seems like from 5pm to 12:30am. The plane may have been checked and bags may have been check b/c of a tip or such. Then after push back again at 12:30 maintenance problems must have occured delaying the flight until 2:12am. The government stuff is just safety steps to make sure things go smooth. Also NW has been known to input the wrong code for the display that appears on the site for reason of delay.
PSU.DTW.SCE From United States of America, joined Jan 2002, 6874 posts, RR: 29 Reply 2, posted (11 years 3 weeks 5 days 11 hours ago) and read 496 times:
Scheduled Departure was at 5:25pm
Actual Departure was at 5:36pm (Delay due to government inspection aka...positive bag matching etc)
Then for how the heck it left the gate and then returned to the gate 7 hours later for maintanance reasons it beyond me. They had to have been airborne and then returned to the gate at DTW 12:39am. That is the unscheduled maintenance part. I don't know what went wrong, but its interesting they diverted all the way back to DTW, but maybe they weren't as far away as it seems. There is no way they spent 7 hours on the ground for a maintenance delay.
Not really enough time for an aircraft swap, but it could be possible. The flight then left again at 2:12am from DTW.