Three years ago I flew my 99 year old aunt (she will be 102 next month) to Michigan on Northwest Airlines. We had DC-9 50 service from West Palm Beach to Detroit and then boarded a DC-9 10 series from Detroit to Lansing. When I asked the flight attendant how old was the plane, she politely said it was built in 1966. Obviously, there were no movies on the plane.

With the number of DC10's they fly to Europe, one wonders how they can afford to fuel them all. But they never crash, so hats off to the maintaince department at Northwest Air. Does anyone know if anyone still flies the 707 or the DC-8?

The 707s and DC-8s that still fly in the US are pretty much exclusively cargo planes (mostly DC-8s), military fuel planes (707) or private carriers (say, John Travolta's personal 707). In non-military aviation, the DC-8 is the predominant "old jet" for whatever reason.

You allude correctly to the main factor in the safety of an older jet: Maintenance, plus sensible retirement of planes as they hit their maximum cycle figure (i.e., max number of pressurizations). NWA announced last week that they would be retiring a number of their DC-9s, which are somewhat less efficient than the mainline Airbuses they fly (although the DC-9s are much, much prettier IMHO).

There used to be quite a lot of 707 freighter planes in S.Am and Africa but the number is small. Re-engined DC8s fly out of Miami down to S/C Am. on a regular basis but no passenger flights on either anymore. You can still find lots of 727 flying around the world especially in less developed areas, the reason that although expensive on fuel the 727 is very popular in remotre regions becuase of the 3 engines. If a twin engine plane gets 'stuck' with an imoperable engine then it is is major logistics to get to where the plane is stuck and change an engine, usually having to fly in huge equipment to do so. Whereas if a 727 has an inoperable engine they simply ferry-fly it back to home base or an airport where they can change an engine. Lots of old Russian aircraft in Shrjah ( just next to Dubai ).

Some interesting info on average age of aircraft can be found here.

http://www.freep.com/money/business/...4_20040124.htm

The DC-10-30s are being replaced rapidly by A330s for both Atlantic and Pacific services. You won't see them for too much longer. But they are indeed ancient. Some are delivered in the early 70's, and because they are in air for longer hours each day than DC-9s, one of their DC-10-30s had the most flying hours of any commerical passenger airplane in history.

In the Pacific, Northwest may still have a couple of 747-200s that are also really ancient. But those are also being replaced by the A330s.