pdx1M

Just remember that on every flight 2 of the most knowledgeable experts on that flight are sitting up in the cockpit. Moreover, they spend more time in the air in those aircraft than virtually any civilian on this board. Finally they generally have just as much interest in getting home at the end of the trip as you do. I'm not suggesting that being curious and even concerned about airline safety standards isn't ok - just that the men and women up front are far more exposed to any hazards than any of us. It's particularly difficult to even answer a question of when a plane last had maintenance because there many levels of maintenance, each with its own rolling schedule based on both flight hours and aircraft cycles (takeoff/landings). The flip answer is that whatever plane you are on probably last had "maintenance" within the last few days. At the other extreme is a heavy "D" check that probably happens every 5-10 years - but then it is nearly a rebuild of the aircraft. While it is nice in some sense to fly new aircraft look at Delta who has focused on older aircraft and yet has some of the most reliable flight dispatch in the industry. Overall, if you are flying a US or other western carrier you're going to be in good shape. As someone who did some flying on post Soviet Union startup airlines that flew old (even by their standards) Tupolov jets believe me on that one.