[ACARS] Northwest Airlines message type 10?

[Joe Stepansky]

An ACARS message came across my screen this morning for which I have no 
definition.  I checked ACARS Online, but there's no message label 10 listed 
for Northwest Airlines.  Any idea what this might be?

I know that 231010 MDT DTW1 means a 23rd day of the month at 1010 UTC from 
Harrisburg, PA to Detroit.  Next line is leaving the gate at Harrisburg, PA 
at 1001 UTC (from flight info at Northwest's web site) and I'm guessing 
wheels up at 1015 UTC.  The DTW line is somewhat of a mystery, as 
Northwest's site doesn't show 1120 UTC as either the scheduled or estimated 
arrival time.  I have no idea what 015900 or 001350/1120 0 might be.

ACARS mode: 2  Aircraft reg: .N8928E [DC9 NWA]
Message label: 10  Block id: 4  Msg. no: M24A
Flight id: NW1889
Message content:-
231010  MDT  DTW1
MDT 1001 1015
DTW 015900 001350/
1120 0
-------------------------------------[23/09/2006 06:16]

Joe Stepansky
Harrisburg, PA