Originally Posted by
RVDT
In a nutshell - no. If the transmissions are of equivalent length only a third party on the same frequency will notice "two in together" and depending on the transmission levels received may hear the modulation of one of the parties with the stronger path. If it is noticed by a third party in some situations they will advise. Without a third party noticing and mentioning "two in together", well....................................? Aviation VHF is normally AM Simplex.
Tenerife was 45 years ago - a lifetime ago in aviation sense. I find it thoroughly shocking that in this age of digital communication that we have a situation where one transmission can 'clobber' another. Digital communications rather than AM simplex should be the way of the future, where each transmitter, regardless of frequency has the entire channel (logically and mutually multiplexed) to themselves, and other transmissions should be artificially muted or at least slightly lower in volume than the main communicators (by design). This is not hard - the industry just has to bite the bullet and do it.
While this may not have been a contributing factor to this incident, it happens so often worldwide that it is a wonder it hasn't been a significant contributor to a number of other near-misses (what a misnomer) or scenes of confusion. Certainly listening to 10 minutes on LiveATC on a busy time will confirm that.
When I stood at the gate at SeaWorld next to the pontoon and watched the helicopter take off and land at short intervals through the wire fence, the thought passed through my mind wondering what could happen if the were multiple aircraft. That was
ten years ago, and this incident triggered that memory vividly. Maybe the number of aircraft may have changed due to demand, however the procedures may not have been adjusted to cope. I'm certain this will be one area that investigators will closely scrutinise.
I would be sorry to see the baby thrown out with the bathwater. The location, right at the waters edge next to SeaWorld was the main attraction for spur-of-the-moment short joy flights for tourists, and even the bystanders were impressed by the noise and backwash of a real helicopter so close by. To shut these down completely would be a sorry result.