wolit (08/11/82)
[This is in response to Will Martin's question about the increased incidence of on-ground holding at busy airports.] This is an easy one: the airlines like to schedule flights at "convenient" times (like 5 or 6 pm) to lure the business travelers. ATC, obviously, cannot handle ten planes all leaving at the same time, so nine of them have to wait. The airlines could certainly save money by not starting engines and "pushing back" from the terminal until they get their clearance (and a reasonable expectation of a timely departure). (While it's true that idling on the ground uses less fuel than holding in the air, the difference isn't all that great for turbojets, and sitting at the gate without starting the engines uses even less -- zero. The airlines' explanation is also intended to cloud the issue, since except for a very few airports -- Denver Stapleton comes to mind -- holding delays on the ground because of expected traffic at the destination just don't exist in fair weather.) The only reason that airlines like to get their planes away from the gate even if they know they'll have to wait on a taxiway if that they can then claim good on-time departure performance (which is measured from the moment of push-back, not takeoff), which looks good in ads!