While cruising with @Jimmi_EAF51 and @EAF51_Havebug towards the frontline, yesterday, we were chatting about radio comms and standard phraseology.
I was telling them about the critical use of the “takeoff” term, which - today - must be used with caution, only in actual clearance messages - from ATC - or subsequent readbacks, and about the dramatic story that led to this bold distinction.
In 1977, a dark chain of events and situations brought two Boeing 747s to occupy the same runway at the same time.
A small airport in Tenerife became overcrowded: following a bomb alarm in the main city airport, a huge amount of traffic had been diverted there. To accomodate the unusual number of planes, taxi lanes were used as parkings and active runway had to be used also for taxi operations. To make things worse, heavy fog blocks roamed through the field, where a ground radar equipment was not installed.
One of the 747s occupying the runway was instructed to backtrack and wait at the threshold, lined-up for subsequent takeoff clearance. The other Boeing should have used part of the runway and then vacate through one of the exits back to normal taxiway.
In such a delicate situation, the use of the “takeoff” word from ATC in a non-takeoff-clearance communication led the crew of lined-up Boeing to understand they were actually cleared for departure. They started their takeoff run while the other jet was still on the runway and disaster happened.
For the sake of knwoledge, here is the whole story:
After reading this, it’s quite clear how incidents always need a chain of events to happen: a single anomaly is not enough to break the shields provided by procedures and safety measurs.
At the same time, it’s also clear how a single word, and its use, can make the difference between normal operations in a complex environment, and disaster.
See you soon airborne and mind your comms!
Cheers!
Gabriele “Ibanez”
