This starts to look like an Allo-Allo ! episode.
So I will say only once
before I start :
The obvious is of course a single use of one language on the RT , and that should also obviously be English.
The obvious thing is to have English only at all international airports ( and that includes CDG !) and even at regional airports as soon as one international , non native aircraft is on the frequency. ( as practiced in Finland for instance )
Now that makes a lot of sense, but unfortunately, the ICAO rules are saying otherwise, and so far no real safety case can be made to oppose dual languages on the R/T .
Tenerife was no dual language, and accent did not play a role at all. Everyone understood everyone else perfectly, the problem was more a crossed RT call, and that one could have helped preventing the collision. Many changes were made by ICAO after TFN, but sadly the technical solution to prevent double transmissions on VHF ( i.e. CONTRAN) has never been mandated. but that is another story.
CDG : sorry , not even a contributing factor, just a possible way that could perhaps have prevented the collision, and for this it is part of the recommendations of the final report ( sadly ignored by the French DGAC to this day )
Cali : no way, the mistake was done much earlier on.
Now the near totality of the runway incursions and collisions are in pure English R/T environment and most of them are in the US. This is not a political statement it is fact.
On the ICAO language proficiency mandate of March 2008, it is for ALL languages spoken on the RT , not only English . Although I agree that that will definitively raise the English level of many Crews and controllers worldwide, this mandate will also limit the mobility of staff as now, level 4 will be required in the second language(s) being legally use on the RT.
So there is still a long way full of hurdles for the UK controllers to work in Aix en Provence ..
So , unfortunately, dual language on the R/T are here to stay I am afraid .
Finally for Capt pit bull , you do not have to buy anything from me because I sell nothing. If you want to see a confirmation of what I said , check ICAO Annexes under IFR rules. It is all there. There is a difference between what is required and what would perhaps make sense for some . A bit like ETOPS..
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