Originally Posted by
NOtimTAMs
Now flying GA IFR A lot these days, I'm puzzled - if both IFR, and as ADSB is mandated and both with flight flans and (presumably) contact with ATC how were they not made aware of proximity? Am I missing something here?
My sincerest condolences to the pilots and passengers families.
Obviously the exact details of what each aircraft was doing at the time are pretty vague. However I will assume it was some kind of approach training happening at the aerodrome. This being the case, it would be almost certain that ATC would have given both aircraft a traffic statement. Then it is on the pilots to separate with each other. However, if controllers observe both aircraft getting in close proximity to each other they will issue a safety alert. There are several possible failure points in this though.
First, it would be assuming either of the aircraft were even still monitoring centre. It is not uncommon for air work aircraft to stop monitoring until their ops normal time. Then they would have to still be in surveillance. I don’t know what the ADSB coverage at YMNG is like, but websites like FR24 give a false indication of the ADSB coverage. They have other ground stations etc that don’t feed into the ATC system. If not on ADSB, then the controller wouldn’t know they were at risk of a collision. Even if they were on surveillance then it still can be missed. Air work aircraft regularly get very close, so that on its own isn’t uncommon. Additionally due to system limitations it’s unlikely the STCA would be available. So unless the controller was watching them very closely, it could be missed. Keep in mind, they quite possibly had a lot of other stuff happening in other parts of the airspace.