Clear as mud if they are ONLY going to allow one take-off every 3 minutes for example - therefore those 3 airlines asking for the 3 pm take-off would take 3 minutes to get into the air. I'm going to assume that under the current system you might have 9 aircraft all lined up for takeoff because they wanted to get out of there at 3 pm, but they would all be airborne within that same 9 minute window. I can see that if only 1 aircraft is taking off every 3 minutes that there might be some down time while flights wait for their slot and then someone is going to yell inefficency because they will ask why are airplanes sitting in the hold short waiting for a controlled take-off time - wasting time and gas.

If an airport can only handle a take-off every 3 minutes then what is the difference which 3 airplanes takeoff in what order?

Also - if a certain flight has a 3 pm departure slot and all other slots are taken up for the enitre hour; and for a variety of reasons that flight pushed back late and was unable to make it's slot, then how do they fit into the flow? Is there an open slot every 5th time slot for stragglers for example?

I understand that a lot of smart people are working on this system so I'm sure that these problems and procedures have been discussed - I'm just asking for someone to *explain* it to me because like I said - I do not have any knowledge of -121 operations. I do know that *we* have a hard time making a take-off time and when the squadrons have even attempted to say that if we are more than 5 minutes late for take-off then we will cancel the flight; well.....that lasts for a about a day until you lost 50-60% of the training scheduled!

Thanks for the input.

USMCFLYR