Brian Campbell on Nostr: nprofile1q…036ma Interestingly, the Blackhawk had it's transponder on, but not ...
nprofile1qy2hwumn8ghj7un9d3shjtnddaehgu3wwp6kyqpqqu56p82wp0ucpu7jkwcvvtfdc7wcmuqkdrqvzpkwl78rdkkckucqv036ma (nprofile…36ma) Interestingly, the Blackhawk had it's transponder on, but not ADS-B. Military aircraft are required to have their transponder on in crowded civilian airspace like this for just this reason, the transponder is an integral part of TCAS, the traffic alert and collision avoidance system.
ADS-B is not required for TCAS to work, but it does provide higher resolution (temporal and spatial) that can make it easier for pilots to keep track of where other aircraft around them are.
Normally ADS-B will turn on automatically when you turn your transponder on, so somewhat odd that it wasn't broadcasting. But we do have the rough flight path of the Blackhawk via MLAT (triangulating the position based on the timing of transponder pings).
At this altitude, TCAS does not provide resolution advisories (it doesn't have enough information to know if telling you to descend is going to send you into an obstacle). But you would expect it to provide a traffic advisory, I believe.
The plane had been put on a circling approach to the runway. A circling approach means you're banked, so its belly was pointed in the general direction the helicopter was in. This makes it harder for the pilot of the airplane to see the helicopter.
It's looking likely that the helicopter pilot thought he had visual contact with the airplane, but actually had visual contact with a different one. And the airplane pilot was banked, may not have been able to see the helicopter, and may not have gotten the best location data about the helicopter.
ADS-B is not required for TCAS to work, but it does provide higher resolution (temporal and spatial) that can make it easier for pilots to keep track of where other aircraft around them are.
Normally ADS-B will turn on automatically when you turn your transponder on, so somewhat odd that it wasn't broadcasting. But we do have the rough flight path of the Blackhawk via MLAT (triangulating the position based on the timing of transponder pings).
At this altitude, TCAS does not provide resolution advisories (it doesn't have enough information to know if telling you to descend is going to send you into an obstacle). But you would expect it to provide a traffic advisory, I believe.
The plane had been put on a circling approach to the runway. A circling approach means you're banked, so its belly was pointed in the general direction the helicopter was in. This makes it harder for the pilot of the airplane to see the helicopter.
It's looking likely that the helicopter pilot thought he had visual contact with the airplane, but actually had visual contact with a different one. And the airplane pilot was banked, may not have been able to see the helicopter, and may not have gotten the best location data about the helicopter.