Originally Posted by
Juggler25
CPDLC is faster than voice with regards to physically issuing the instruction (there's no typing involved). However, it is slower than voice with regards to the actual aircraft physically performing the instruction. This is due to the time lag in the instruction being sent and received by the aircraft, the pilot acknowledging the message, then the pilot initiating the clearance.
I would disagree with that statement. It really depends on the local circumstances, airline, airframe and the kind of clearance. At Maastricht we can uplink complex clearances (ie. descend FL280 reach level by FIX) with a WCO received within 10 seconds from certain aircrews who are on the ball with CPDLC. In that amount of time I would barely finish the clearance and would be waiting for a full readback on voice.
I agree though, that as a controller you can't be sure of an instant reply due to the possible long latency - which is fortunately less and less the case.
So up to CPDLC everyone - please