A related question: to what extent do the priorities which Dublinpilot quotes override the principal of the safe and expeditious movement of traffic?
An example which happened to me today, although I've been subject to several other examples. I was at the holding point for the runway, checks complete, and with my clearance copied. I had waited for two aircraft in front of me to depart, and I was now next for departure, with one aircraft on final. I was in a light twin, and my training flight would have been category Z.
At around this point, a commercial aircraft - B737 - called for taxy. He was given taxy clearance to a holding point a little way behind me. As he was taxying, the aircraft on final landed and cleared the runway, and I expected to be cleared to line up. Instead, the B737 was given a line up and backtrack from the intersection behind me.
The controller's explaination (which he offered me without me asking, btw) was that he had a slot to meet. Interestingly, the reason given was not to do with the category of our repsective flights.
My point is this: after he departed, I had to wait further due to his wake vortex. Alternatively, had I lined up first, he could have taxied to line up behind me without even having to come to a stop. Probably by the time he was lined up on the runway, I could have been airborne, at a safe height, and given radar vectors to take me away from his climb-out. Certainly, due to wake vortex, any delay to him would have been far less than the delay to me that was incurred by letting him go first, and I'm not convinced that a delay of (literally) a few seconds can make the difference between making a slot and not. This seems to me to be a more expeditious way of sequencing the traffic, since it removes the need for any wake vortex delays.
So how significant are factors like prioritisation categories and the need to get commercial airways flights away on time, compared to running a generally expeditious operation? Not a complaint, by the way, just a query.
FFF
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