United Flight 885 asks:
The crew of UA885 saw the aircraft was coming down short of the runway.
Did they communicate with OZ214 by radio to warn them or not? Do regulations prevent them from doing so? Could they have contacted the tower instead?
This thought has been in the back of my mind for several days now, and I bet the UA crew are bitterly regretting that they didn't say something – although whether it would have been responded to or not is another matter!
Every air traffic control frequency is under the control of the ATCO who is providing the service on that frequency. A pilot would virtually never speak directly to another pilot, although that is simply a matter of pressing the transmit button. Usually what happens is to speak
through the ATCO i.e. "Tower, doesn't the 777 on finals look a little low?" This serves to bring everyone's attention to the situation and the Controller might well respond with a call to the 777 such as "Asiana 214, you look a little low, are you OK?" The ATCOs are reluctant (appropriately) to tell pilots
how to fly the aircraft, they just give us the challenges!
I suspect the UA pilots also thought that the aircraft was very slow too; a 30 knot reduction in normal approach speed would be noticeable I would have thought.
In emergency of course (as here), the UA pilot(s) could have transmitted on the Tower frequency "Asiana 214, you are low and slow, pull up, pull up!" or something, as has already been suggested.
As I said, they will be regretting they didn't, but this is water under the bridge now.
Edit: I don't mean to be ungenerous towards ATC. They do a fantastic job, although some places concentrate the mind a little more than others!