4 ms·
Assuming the liveatc audio in the article has not been edited, it sounds like there's about 10 seconds between ATC giving go around and the United pilot saying
by exDM69 9y ago
Assuming the liveatc audio in the article has not been edited, it sounds like there's about 10 seconds between ATC giving go around and the United pilot saying they flew right over. With instructions given to Air Canada in between so it might have been seconds earlier.
Based on that, it was seconds away from a collision. It seems like a near miss when considering aviation safety margins.
- CaliforniaKarl 9y agoWhat's missing is, when (relative to radio traffic) did the pilot begin the go-around maneuver. Did they begin doing so before being told to go around, or did they only start to do so after?
- exDM69 9y agoIf the pilot initiates a go around they need to announce it to the ATC. It is usually a drastic full power pull up that will certainly disrupt nearby air traffic. So the pilot probably did not start the go around before being told so.
- CaliforniaKarl 9y agoSorry, I have to partially disagree. The FAA is pretty clear on this: The priorities (in order) are Aviate, Navigate, and Communicate[1]. The pilot is ultimately the person responsible for the safe operation of the aircraft. That will occasionally mean performing a maneuver before telling anyone. In response to this, procedures are designed so that pilots can safely abort an approach without posing a danger to themselves (i.e. running into terrain) or other aircraft. For example, let's look at the LDA PRM runway 28 Right approach [2] into SFO, which the pilot may have been flying. If you have to abort the approach prior to the DARNE waypoint, you make a climbing right turn to heading 030 and 3000 feet, then you proceed directly to the Oakland VOR, and then you hold as published. When Approach clears you for this approach, the controller is also clearing you to fly the missed approach, if needed. If you have to go missed-approach after DARNE, the instructions are similar, but are documented in [3] instead of in [2]. But note the "unless otherwise instructed by ATC". In this case (see [4]), Tower placed the pilot onto runway heading, likely with a climb to avoid the hills. Approach would then have taken over, and brought the pilot back around. [1]: https://www.faasafety.gov/gslac/ALC/course_content.aspx?cID=40 https://www.faasafety.gov/gslac/ALC/course_content.aspx?cID=... [2]: http://155.178.201.160/d-tpp/1707/00375LDAPRM28R.PDF http://155.178.201.160/d-tpp/1707/00375LDAPRM28R.PDF [3]: http://155.178.201.160/d-tpp/1707/00375PRMAAUP.PDF http://155.178.201.160/d-tpp/1707/00375PRMAAUP.PDF [4]: https://flightaware.com/live/flight/ACA759/history/20170708/0055Z/CYYZ/KSFO https://flightaware.com/live/flight/ACA759/history/20170708/...
- exDM69 9y agoYes, it's impossible to tell from the footage but I would have assumed hearing the pilot, not the ATC call for go around if it was pilot initiated. But you're right, the pilot may have started the go around but we can't tell what happened from the footage.
- dx034 9y agoI would assume it was edited. He only joins the frequency about 30 seconds before it happens. That means tower only took control once he was 60 seconds before landing. I don't know the procedures at SFO but that seems too short.
- mikeash 9y agoIt has been edited. The LiveATC archive has about 40 seconds between "go around" and "flew directly over us." The LiveATC archive appears to be edited to remove silence, so it may have been even longer.