Hi Folks
I still remain firmly in favour of the use of the word "expedite", but I came across a situation recently where its use had no effect on how we operated the aircraft. It is quite a specific situation, but there wasn't really anything we could do to "expedite", however the frequency was too busy to let the controller know. I thought mentioning it here might be useful.
It occurred in a land far-far away where the temperature is already mid to high 20s (celcius degrees) and the SID cleared level is 4000'. On first contact with the departure controller we were told to expedite to 4000'. We were nearly at max take-off weight, so we were using very little derate for the take-off. At this weight the flap limit speeds are very close to the minimum speeds that can be flown in a given configuration and we are also wary about EGT exceedences and remembering the 5min limit for take-off power.
Ideally we want to accelerate smoothly through the flap retraction whilst reducing our rate of climb (and in this case making a large turn). The problem came in that we were already part way through the retraction when the controller asked us to expedite. Since I like to keep away from speeds which cause warnings, we had no realistic choice but to continue with the retraction at our reduced rate of climb. Since we got to about 3000' before the flaps were up, there is a 250kt limit below 8000' at this airfield and our minimum clean speed was 250kts, we had no tricks left up our sleeve.
I think the main point I am driving at is that the use of "expedite" by departure controllers in hot places with heavy aircraft and low cleared altitudes is probably not going to achieve anything.
Just my opinion (and I know there were a few things we could have done slightly differently with the flap retraction, but would I don't think that the effect would have been noticeable).
All the best
G W-H