Travellight:
With the full realization that I'm becoming the Cliff Claven of FlyerTalk, your dates are off by a little.
The first 747-300 was delivered to Swissair on 3/19/83. KL took delivery of its first -300 on 4/30/83, so its about 16 years old. There are one or two -200s that were converted to 200SUDs prior to the development of the -300.
NW was the launch customer for the -400 and took delivery of the first -400 on 4/29/88, so its about 11 years old. I'd be more concerned about NWs DC10-30/40s which are pushing 20 to 25+ years old.
Agree with all other statements about KL vs NW service levels.
Robert Johnson
danville 1K