Here is a resource for all you flightplanners, and for those who are just curious to explore the airlines of yesterday. s The JP Fleets Book was recently ended, but for decades and decades, it was the "go to" source for airline fleet data. A good friend was kind enough to share his digital copies of several of the books with me for my 1998 project, and said as long as I host them myself, he does not mind if I share them.
These books are very accurate, however, the limitation is that they are generally printed in February or so each year. This means in the 1998/1999 book, for example, any leases or other changes to the fleet that were decided after February of 1998 will not be included in the 1998/1999 book, even if the aircraft were active obviously. Likewise, if that same aircraft was out of the fleet, or scheduled to be out of the fleet, by the time the 1999/2000 book was to be printed, then it "slips through the cracks" and is not in either book. But outside of those instances(which are more common than one might think), this is a solid resource. Most government transport aircraft and general aviation companies are also included. Please enjoy these great pieces of history: